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Lele, Stephen, and slele@bigpond net au. "Additives on the Curing of Phenolic Novolak Composites." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070205.095402.
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The research programme studied the cure reaction of a phenolic novolak resin and the effects of various additives and fillers on the reaction. The programme utilised the recently developed thermal analysis technique of temperature-modulated differential scanning calorimetry (TMDSC) performed in conjunction with other available thermal analysis techniques. TMDSC enables the signal for the heat of reaction to be separated from the underlying specific heat change in the resin. This meant that the reaction could be studied without interference from any physical changes in the resin. The manufacture of composite brake materials required the use of numerous additives and fillers to produce the desired properties. The influence of such additives on the cure rate and final properties of the resin was known to occur but had not previously been measured due to the difficulties presented by the presence of opaque additives. Some additives also underwent thermally induced physical changes in the temperature range of the cure. The final properties and the processing of new brake materials undergoing development often required trial and error adjustments to compensate for changes in cure rate. An understanding of the influence of additives would enable more rapid commercial development of brake materials through an improvement in the ability to predict both the properties of the product and the optimal processing parameters. Processing efficiency could also be improved through detailed knowledge of the kinetics. Moulding cycle times and post-baking times and temperatures were longer than necessary in order to ensure adequate cure at the end of each stage because of the lack of kinetic data. The cure of phenolic resin has been shown to be highly complicated with numerous alternate and competing reactions. For the manufacture of composite materials, knowledge of the kinetic parameters of individual reactions is not considered to be important; rather the overall kinetic parameters are required for prediction. Therefore the kinetic model parameters that best described the observed behaviour were chosen even though the model had no basis in the molecular interaction theory of reaction. Rather it served as a convenient tool for predictions. Characterisation of the resin proved to be difficult due to the presence of overlapping peaks, and volatile reaction products. TMDSC was successfully used to determine the reaction kinetics of the pure resin and the influence of certain additives on the reaction kinetics. The determination of the kinetic parameters using TMDSC agreed well with the traditional Differential Scanning Calorimetry isothermal and non-isothermal techniques. Both the Perkin-Elmer and TA Instruments were utilised for the research and were found to provide reasonably good agreement with each other. The capabilities and limitations of the individual instruments were critically examined, frequently beyond the manufacturers' specifications. TMDSC suffers from a limitation in the heating rate of the sample compared to DSC. However, it was observed that valuable information could still be obtained from TMDSC despite using heating rates that were higher than specified by manufacturers. Hot Stage Microscopy and thermogravimetry were additional experimental techniques used to aid in the characterisation of the resin. Some inhomogeneity of the resin was identified as well as differences in the behaviour of the cure between open (constant pressure) and closed (constant volume) environments were observed. A novel method of determining the orders of the cure reactions and their kinetic parameters was utilised. Reaction models for the overall cure reactions were postulated and tested by fitment to sections of experimental data in temperature regions which appeared to be free of interference from overlapping peaks. Once an individual peak was reasonably well modelled, adjacent overlapping peaks were able to be modelled both individually and in combinations by fitment to experimental data. The Solver function in Microsoft Excel was utilised to find the best fitting model parameters for the experimental data. The model parameters were able to be refined as overlapping peaks were progressively incorporated into the calculations. This method produced results that agreed well with the traditional method of analysing reaction peak temperatures at multiple scanning rates. Model fitment was shown to be of benefit where overlapping reactions occur. Various model scenarios could be tested and optimised to particular sections of experimental data. This enabled the researcher to easily identify areas of possible anomalies and postulate alternative scenarios. The accuracy of the postulated model was able to be determined by its successful fitment to experimental data from experiments run under different conditions.
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Martins, Maria Ana Pignatel Marcon. "Obtenção e estudo de blendas binarias e ternarias de polimida (S) Novolak." reponame:Repositório Institucional da UFSC, 1996. http://repositorio.ufsc.br/xmlui/handle/123456789/76971.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Fisica e MatematicaMade available in DSpace on 2012-10-16T23:35:01Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T21:00:26Z : No. of bitstreams: 1 106208.pdf: 1521509 bytes, checksum: e36d597ed367c60809be6a556951c511 (MD5)
No estudo de blendas poliméricas (a mistura física de polímeros ) pode-se obter novos materiais com propriedades diferentes dos componentes puros. A miscibilidade é favorecida quando existe interações entre os componentes da mistura. Neste trabalho as blendas foram preparadas pela mistura mecânica dos componentes fundidos e resfriado-se a mistura para preparação de filmes numa prensa sob aquecimento. Para as misturas de Poliamida 12 (um polímero semi-cristalino)/Novolak (oligômero fenólico) os resultados das análises das diferentes técnicas utilizadas (densidade, FTIR, DSC, etc), mostraram a ocorrência de interações através de ligações de hidrogênio e portanto a ocorrência de miscibilidade da blenda. O valor negativo do parâmetro de Flory-Huggins confirma a miscibilidade da blenda Poliamida 12/ Novolak. Para a blenda ternária Poliamida 6/grilamid TR-55/Novolak os resultados de densidade e calorimetria diferencial de varredura indicam uma parcial miscibilidade da blenda.
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Artmann, Albertina. "Estudo para a otimização do processamento de formulações de resina fenólica aplicada à material de fricção." reponame:Repositório Institucional da UCS, 2008. https://repositorio.ucs.br/handle/11338/369.
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Materiais de fricção são compósitos cuja matriz polimérica é, usualmente, a resina fenólica novolaca. Os requisitos de desempenho dos materiais de fricção demandam um rígido controle das condições de processamento, na formação de ligações cruzadas da resina fenólica de hexametilenotetramina (HMTA), que definem as propriedades do produto final. Nesta dissertação, resinas fenólicas novolaca pó, com teores de 7, 9 e 11% do agente de cura hexametilenotetramina (HMTA), foram caracterizadas quanto ao peso molecular, além da determinação do comportamento térmico e reológico, objetivando sua aplicação como matriz polimérica em materiais de fricção. Os resultados obtidos, principalmente em função das taxas reacionais obtidas das caracterizações reométricas, indicaram a resina fenólica novolaca com 9% de HMTA, como a melhor para o processamento de material de fricção rápido.Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-22T18:37:45Z No. of bitstreams: 1 Dissertacao Albertina Artmann.pdf: 2110638 bytes, checksum: 638291da288591193fe26a9cdeeb5627 (MD5)
Made available in DSpace on 2014-05-22T18:37:45Z (GMT). No. of bitstreams: 1 Dissertacao Albertina Artmann.pdf: 2110638 bytes, checksum: 638291da288591193fe26a9cdeeb5627 (MD5)
Friction materials are composites the polymer matrix of which is usually a novolak phenolic resin. Performance requirements of friction materials demand a steep control of the processing conditions, during crosslinking development of the phenolic resin with hexamethylene tetramine (HMTA), which define the end product properties. In this dissertation, aiming at applyind these materials as a polymer matrix in friction materials, powdered novolak phenolic resins having 7, 9 and 11wt% of hexamethylene tetramine (HMTA) curing agent were characterized as for molecular weight, molecular weight distribution, besides the determination of thermal and rheological behavior. Obtained data based rate of reaction mainly on rheological characterization indicate the 9wt% HMTA novolak phenolic resin for the processing of a typical friction material.
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Eisenheld, Leopold. "Measuring the Adhesive Bond Quality of Vinyl Ester-Glass Composites on Novolak HMR Treated Wood." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/EisenheldL2003.pdf.
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Chung, Song-Jo [Verfasser], H. [Verfasser] Hein, and J. [Verfasser] Schulz. "Strukturprofilsimulation dicker Schichten in der optischen Lithographie mit DNQ-Novolak-basierenden Photoresists / Song-Jo Chung, H. Hein, J. Schulz." Karlsruhe : KIT-Bibliothek, 1998. http://d-nb.info/119822309X/34.
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Voigt, Anja. "Zur Chemie photolytisch generierter Arylnitrene in Polymermatrizen." Doctoral thesis, [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=955351111.
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Höer, Martin. "Einfluss der Material- und Verarbeitungseigenschaften von Phenolharzformmassen auf die Qualität spritzgegossener Bauteile." Doctoral thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-155078.
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Spritzgießbare Duroplaste zeichnen sich durch hohe thermo-mechanische Beständigkeit, geringe Schwindung und niedrige Materialkosten aus. Damit können die Anforderungen an spritzgegossene Präzisionsbauteile für den Automobilbau erreicht werden. Im Rahmen der vorliegenden Arbeit werden unterschiedliche Novolak-Phenolformmassen hinsichtlich ihres hygroskopischen Verhaltens und dessen Auswirkung auf die Spritzgießverarbeitung und die Bauteilqualität untersucht. Das Absorptionsverhalten kann mithilfe der Fick’schen Diffusionsgesetzte näherungsweise beschrieben werden. Auf Basis von mechanischen Untersuchungen sowie der Beurteilung der Maßhaltigkeit eines Präzisionsdemonstrators hinsichtlich Schwindung und Verzug wird zudem der Einfluss der Prozessparameter beim Spritzgießen bestimmt. Die vorgestellten Untersuchungen zeigen die Grenzen der Verarbeitung und der realisierbaren Bauteilqualität auf, die auf die großserientaugliche Verarbeitung von duroplastischen Bauteilen übertragen werden könnenInjection moldable thermosetting materials show excellent material properties, e.g. high thermo-mechanical resistance and reduced shrinkage in combination with low material cost. Thus, technical requirements for high performance parts for automotive applications can be achieved. In the scope of this work different phenolic novolac compounds were investigated regarding their hygroscopic behavior with its influence for injection molding and product quality. The absorption can be approximately described by Fick’s-Diffusion-Model. The interrelationship of injection molding parameters and the thermo-mechanical behavior is examined on the basis of mechanical testing and the assessment of the dimensional accuracy for a thermoset high precision part. The presented investigations point to the limit of processing and realizable part quality which can be transferred for high performance parts molded in mass production
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Pöhlmann, Milena. "Thermisch härtende Polymerverbundmaterialien als Basis für neue Befestigungssysteme." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1165492370619-99312.
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Mit der Entwicklung und Einführung ökologischer Bauweise im Neubau sowie neuen Baustoffsystemen in Sandwichbauweise wird es zunehmend erforderlich, neue effektive Befestigungsvarianten zu entwickeln, die eine dauerhafte Fixierung auch unter sicherheitstechnischen Bestimmungen sowie aus Garantie- bzw. haftungsrechtlichen Gründen ermöglichen. Die aus der Praxis bisher bekannten chemischen Befestigungssysteme (Zweikomponentenverbundmörtel, Verbundankerpatronen) weisen hinsichtlich der Applikation unter bautechnischen Bedingungen noch einige Nachteile auf. Dazu gehören vor allem längere Aushärtungszeiten zur Realisierung der abschließenden Verbundfestigkeit, Inhomogenitäten im Verbund, der Einsatz toxischer Verbindungen und eine Limitierung der Applikationsmöglichkeiten in horizontalen und Überkopf-Einsatzbereichen sowie Hohlkammersystemen. Alle zuvor genannten Punkte haben bis jetzt die Nutzung solcher Verbundwerkstoffe als universale Anwendungsmöglichkeit verhindert. Ein neues chemisches Befestigungssystem, welches aus Novolak gehärteten mit Hexamethylentetramin (Hexa) und anorganischen Füllstoff besteht, wurde für Applikationen in Beton entwickelt. Das Bindemittel härtet bei der Temperaturzuführung aus. Die unkatalysierte Befestigungsmasse zeigt bei einer Temperatur zwischen 150-300 °C eine hohe Reaktivität. Die Vorteile dieses Systems sind die unbegrenzte Lagerfähigkeit der vorgemischten härtbaren Masse sowie die Gewährleistung einer homogenen Netzwerkstruktur im gesamten Verbund und sie ist frei von giftigen und flüchtigen Substanzen. Auf den Einsatz toxischer Substanzen wurde verzichtet. In dieser Arbeit wurde die Gesamtkinetik der Reaktion während des Aushärtungsprozesses dieser Polymerkomposite untersucht. Die DSC- (nicht-isothermen, isothermen) und MDSC-Untersuchungen haben sich als ein sicheres Verfahren zur Qualitätskontrolle des Aushärtezustands der Befestigungssysteme herausgestellt. Parallel zur nicht-isothermischen und isothermischen DSC wurden Leitfähigkeitsmessungen durchgeführt, um den Endpunkt der Aushärtungsreaktion zu bestimmenThe development and introduction of ecological construction methods and the use of sandwich materials make it necessary to develop new fixing systems and technologies. Dealing with the application in concrete and other substrates commercial chemical fixing systems show some disadvantages up to date. Especially the rather long curing time in order to realize the final bond strength, inhomogenities in the composite, the partial use of toxic substances and application limits of such systems in horizontal direction as well as hollow section materials has so far prevented the use of such composites for all-purpose applications. A new chemical fixing system, which consists of hexamethylene tetramine (hexa) cured novolac and inorganic filler, was developed for application in concrete. It is applied by a thermo-curing procedure. The uncatalyzed curable mixture has a high reactivity at temperature between 150-300 °C. Compared with commercial chemical fixing systems, the premixed curable mass has many benefits. First it has a unique storage stability and second, it is free of toxic and volatile substances. Another important aspect is, it is self-foaming. In this study was investigated the overall kinetics of the reaction during the curing process of these polymer composites. An appropriate method for this experiment proved to be the DSC in isothermal and non-isothermal mode and MDSC. This turned out to be a safe quality control technique for these systems. Parallel to the non-isothermal and isothermal DSC conductivity measurements have been performed to determine the end point of the curing reaction
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Hardrict, Shauntrece Nicole. "Novel Novolac-Phthalonitrile and Siloxane-Phthalonitrile Resins cured with low melting Novolac Oligomers for Flame Retardant Structural Thermosets." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9669.
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The chemical modification of low molecular weight novolac oligomers and siloxane/silane-containing monomers has led to novel phthalonitrile derivatives with low glass transition temperatures, ranging from -25 to 75 ºC. Multi-functional, low molecular weight phenol-formaldehyde novolac resins were blended with these novel phthalonitrile derivatives to achieve low viscosity resin blends. Moderate temperatures and rapid curing cycles were employed (200 ºC, 1 h and 225 ºC, 4h) to produce networks with high glass transition temperatures (> 250 ºC). A decrease in the sharp band at 2230 cm⁻¹, attributed to the nitrile functionality of the phthalonitrile resin, was monitored in FTIR studies and indicated the progress of the reactions. Ninety percent conversion was achieved within ~ 30 min.
Thermal analysis of siloxane-phthalonitrile/novolac networks cured for 1h at 200 ºC and 4h at 225 ºC did not exhibit glass transition temperatures below 250 ºC. In dynamic TGA studies, 5% weight loss temperatures up to 418 ºC were observed, and the materials exhibited 50 to 56 % char at 800 ºC in nitrogen. Networks prepared from a resin blend containing 50 weight% of a phthalonitrile derivative of a 260 g mol⁻¹ novolac oligomer, 50 weight% of the 260 g mol⁻¹ novolac oligomer, and 1.5 mol % triphenylphosphine (based on novolac) (NOV/NOV/TPP) cured at 200 ºC for 1h, did not exhibit a Tg below 250 ºC via DSC. These networks exhibited a 5% weight loss temperature of 350 ºC, and 70 % char at 800 ºC in TGA studies under nitrogen. This degree of char formation makes these materials appealing for use in carbon-carbon composites. Post-curing these networks at 200 ºC for 1h, and then at 225 ºC for 4h, resulted in high thermo-oxidative stability, with a 5% weight loss observed at 447 ºC and 50 % char at 800 ºC.
Blending tetramethyldisiloxane phthalonitrile monomers with 260 g mol⁻¹ novolac oligomers afforded prepolymer resins with low melt viscosities, 560 mPa s at 80 ºC. Such viscosities may allow these resins to be processed via vacuum assisted resin transfer molding (VARTM) at low temperatures and heated at elevated temperatures to produce flame resistant three-dimensional networks.Master of Science
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Lin-Gibson, Sheng. "Cresol Novolac/Epoxy Networks: Synthesis, Properties, and Processability." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/27296.
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Void-free phenolic networks have been prepared by the reaction of phenolic novolac resins with various diepoxides. The stoichiometric ratio can be adjusted to achieve networks with good mechanical properties while maintaining excellent flame retardance. A series of linear, controlled molecular weight, 2,6-dimethylphenol endcapped cresol novolac resins have been synthesized and characterized. The molecular weight control was achieved by adjusting the stoichiometric ratio of cresol to 2,6-dimethylphenol and using an excess of formaldehyde. A dynamic equilibrium reaction was proposed to occur which allowed the targeted molecular weight to be obtained.
A 2000 g/mol ortho-cresol novolac resin was crosslinked by a diepoxide oligomer and by an epoxidized phenolic oligomer in defined weight ratios and the structure-property relationships were investigated. The networks comprised of 60 or 70 weight percent cresol novolac exhibited improved fracture toughness, high glass transition temperatures, low water uptake, and good flame retardance. The molecular weights between crosslinks were also determined for these networks. The stress relaxation moduli were measured as a function of temperature near the glass transition temperatures. Crosslink densities as well as the ability to hydrogen bond affect the glassy moduli of these networks. Rheological measurements indicated that cresol novolac/epoxy mixtures have an increased processing window compared to phenolic novolac/epoxy mixtures.
Maleimide functionalities were incorporated into cresol novolac oligomers, and these were crosslinked with bisphenol-A epoxy. The processability of oligomers containing thermally labile maleimides were limited to lower temperatures. However, sufficiently high molecular weight oligomers were necessary to obtain good network mechanical properties. Networks prepared from 1250 g/mol cresol novolac containing maleimide functionilities and epoxy exhibited good network properties and could be processed easily.
Latent triphenylphosphine catalysts which are inert at processing temperatures (~140°C) but possess significant catalytic activity at cure temperatures 180-220°C were necessary for efficient composite fabrication using phenolic novolac/epoxy matrix resins. Both sequestered catalyst particles and sizings were investigated for this purpose. Phenolic novolac/epoxy mixtures containing sequestered catalysts exhibited significantly longer processing time windows than those containing free catalysts. The resins also showed accelerated reaction rates in the presence of sequestered catalysts at cure temperatures. Trihexylamine salt of a poly(amic acid) was sized onto reinforcing carbon fibers and the composite properties indicated that fast phenolic novolac/epoxy cure could be achieved in its presence.Ph. D.
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ASHIRGADE, AKSHAY A. "ENVIRONMENTALLY-COMPLIANT NOVOLAC SUPERPRIMERS FOR CORROSION PROTECTION OF ALUMINUM ALLOYS." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1153245386.
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Chávez, Arraya Iván Manuel, Mosqueira Iván Alberto Marroquín, and Cabrera David Jean Maticorena. "Planeamiento estratégico de la Empresa Novopan Perú." Master's thesis, Pontificia Universidad Católica del Perú, 2018. http://tesis.pucp.edu.pe/repositorio/handle/123456789/11751.
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Novopan Perú es una empresa fundada en el año 1978, con el objetivo de importar y
comercializar tableros de madera aglomerada con melamina. Forma parte de una corporación,
cuya casa matriz está en Ecuador, donde se encuentra la planta productora, que utiliza
tecnología de punta para fabricar tableros de alta calidad y con capacidad para atender el
incremento en la demanda. Con el fin de que esta empresa pueda desarrollar una ventaja
competitiva se ha creado el presente plan estratégico, usando el modelo secuencial diseñado
por D’Alessio (2015). En este proceso, se diseñó una nueva misión y una nueva visión, en la
que se propone consolidar su liderazgo en el mercado peruano, generando rentabilidad y
dando empleos dignos, con formación profesional constante. La manera en que se logrará
esto es mediante la implementación de estrategias, que han sido ampliamente analizadas e
incluyen aspectos como la penetración en el mercado y el desarrollo de nuevos productos o
servicios. Adicionalmente, se contempla la integración vertical hacia adelante, mediante
ventas a través de una página web, así como por una red de tiendas propias. Esto permitirá
reducir la dependencia que, en la actualidad, se tiene en dos grandes distribuidores; al mismo
tiempo que se ampliará la base de clientes y de consumidores finales. Para el año 2022, se
espera tener una empresa integrada hacia atrás, con la producción en Ecuador, y hacia
adelante, llegando a los usuarios finales y atendiendo varios segmentos del mercado nacional,
con presencia en las principales provincias del PerúNovopan Peru is a company founded in 1978, with the objective of importing and commercializing agglomerated wood boards, with melamine. It is part of a corporation, whose head office is in Ecuador, where the production plant is located, which uses state-ofthe- art technology to manufacture high-quality boards with the capacity to meet the increase in demand. In order for this company to develop competitive advantage, this strategic plan has been created, using the Sequential Model designed by D'Alessio (2015). In this process a new mission and a new vision was designed, where it is proposed to consolidate its leadership in the Peruvian market, generating profitability and giving decent jobs, with constant professional training. The way in which this will be achieved is through the implementation of strategies, which have been widely analyzed and include aspects such as market penetration and the development of new products or services. Additionally, vertical integration is contemplated, through sales through a web page, as well as through a network of own stores. This will reduce the dependency that currently exists in two large distributors, while expanding the base of customers and final consumers. By the year 2022 it is expected to have an integrated company backwards, with production in Ecuador, and forward, reaching end users and serving several segments of the national market, with a presence in the main provinces of Peru
Tesis
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Espinosa, Fernandez Manuel Alejandro. "Nuevos polímeros retardantes a la llama: sistemas novolaca-benzoxazina-epoxi." Doctoral thesis, Universitat Rovira i Virgili, 2004. http://hdl.handle.net/10803/8991.
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Los polímeros orgánicos, tanto naturales como sintéticos, son inherentemente combustibles y en presencia de una fuente de calor y de oxígeno se queman fácil y rápidamente. Aunque en los últimos años ha habido un incremento en el número de heteroelementos utilizados en compuestos retardantes a la llama, el mercado está todavía dominado por compuestos que contienen halógenos, especialmente cloro y bromo. Estos compuestos son excepcionalmente efectivos pero presentan el inconveniente que incrementan las cantidades de humos y productos de descomposición tóxicos y corrosivos que se desprenden durante la combustión del polímero. Como alternativa a estos, han surgido una nueva clase de resinas termoestables basadas químicamente en 3,4-dihidro-2H-1,3-benzoxazinas. Su síntesis es de gran simplicidad y se lleva a cabo por condensación de formaldehido con fenoles en presencia de aminas aromáticas en una relación molar determinada. Otra de las aproximaciones utilizadas recientemente ha sido el uso de compuestos organofosforados que han demostrado buena capacidad como retardantes a la llama para resinas epoxi a la vez que generan menos gases tóxicos y humos que los compuestos halogenados. El objetivo general de este trabajo ha consistido en el desarrollo de nuevos sistemas poliméricos termoestables resistentes al fuego, sin detrimento de las propiedades del material y no agresivos medioambientalmente. Se pretende mejorar las buenas propiedades de algunos materiales estándar actualmente empleados, resinas fenólicas y resinas epoxi, pero introduciendo la condición de no inflamabilidad mediante nuevos sistemas de ignifugación, basados en fósforo y nitrógeno, alternativos a los sistemas halogenados clásicos ampliamente utilizados en la actualidad, mucho más tóxicos y peligrosos para el medioambiente que los que se proponen como alternativa en este estudio. Para ello se ha llevado la síntesis y caracterización de sistemas entrecruzados basados en resina novolaca modificados en diferentes proporciones con anillos del tipo benzoxazina, utilizando un nuevo método de síntesis basado en el uso de 1,3,5-trifenilhexahidro-1,3,5-triazina. Se ha estudiado mediante calorimetría diferencial de barrido su comportamiento térmico así como la influencia que tienen los catalizadores en la temperatura de apertura de los anillos de benzoxazina. La estabilidad térmica de estos compuestos se ha estudiado mediante análisis termogravimétrico en atmósfera de nitrógeno y de aire. Estos sistemas presentan buena estabilidad térmica, aunque el tanto por ciento de modificación no parece influir en las propiedades térmicas de estos. Mediante análisis dinamomecánico se ha descrito que la modificación de resinas novolaca con anillos de benzoxazina permite obtener materiales con una buena integridad mecánica, pudiéndose establecer relaciones cualitativas de niveles de entrecruzamiento. La retardancia a la llama de estos materiales ha sido V-O y V-1 en función del grado de modificación según el test de inflamabilidad UL-94 V.
En este trabajo también se han sintetizado compuestos epoxifosforilados para modificar los sistemas novolaca y novolaca-benzoxazina y estudiar sus propiedades térmicas, mecánicas e ignífugas. Estos glicidilos no contienen enlaces hidrolíticamente inestables y poseen óxido de fosfina en su estructura. Se ha sintetizado un nuevo monoglicidilfosfinato, el 10-óxido de 10-(2,3-epoxipropil)-9,10-dihidro-9-oxa-10-fosfafenantreno (DOPOGly) y un diglicidilo alifático que contiene óxido de fosfina en su estructura, el óxido de isobutilbis(glicidilpropiléter)fosfina (IHPOGly). El entrecruzamiento de resinas novolaca y novolaca-benzoxazina con DOPOGly y IHPOGly lleva a sistemas novolaca-epoxi y novolaca-benzoxazina-epoxi con distinto contenido de fósforo y diferente densidad de entrecruzamiento que no desprenden volátiles en la reacción de polimerización. Se ha podido ver mediante análisis termogravimétrico que la incorporación de enlaces C-P en estos sistemas disminuyen la estabilidad térmica de estos, a la vez que el contenido final de fósforo en los polímeros no influye en el resto carbonado a 800ºC en atmósfera inerte y si lo aumenta en atmósfera oxidante. Los sistemas novolaca-epoxifosforada presentan menor velocidad de degradación a grados de conversión elevados de acuerdo con la propuesta de formación de un residuo intumescente mientras que los sistemas novolaca-benzoxazina-epoxi presentan un mecanismo de descomposición complejo y no pueden relacionarse con la presencia de este. Al igual que en los sistemas novolaca-benzoxazina, se han podido establecer relaciones cualitativas de niveles de entrecruzamiento para los sistemas novolaca-benzoxazina-DOPOGly. Para los sistemas novolaca-IHPOGly y novolaca-benzoxazina-IHPOGly se han podido determinar la temperatura de transición vítrea que no había sido posible determinar por DSC y también las temperaturas de las transiciones secundarias que se han relacionado con la estructura química de los materiales. Finalmente, la adición de compuestos organofosforados a los sistemas novolaca y novolaca-benzoxazina de mayor grado de modificación, mejora su retardancia a la llama alcanzándose grados V-0 según el test UL-94 V.
Natural and synthetic organic polymers are inherently combustible and in presence of heat and oxygen source burn easy and quickly. Although in the last years there has been an increment in the number of heteroatoms used in flame retardant compounds, the market is still dominated especially by compounds that contain halogens, like chlorine and bromine. These compounds are exceptionally troops but they have the shortcommings as the increase in the quantities of smoke and toxic gases and corrosive decomposition products that come off during the polymer combustion. As alternative to these a new class of thermostable resins chemically based in 3,4-dyhidro-2H-1,3-benzoxazines has arisen. Its synthesis is of great simplicity and it is carried out by formaldehyde condensation with phenols in presence of aromatic amines in a fixed molar relationship. At the same time another of the approaches used recently has been the use of organophosphorated compounds that have demonstrated good capacity like flame retardants for epoxy resins because they generate less toxic gases and smoke that the halogenated compounds.
The general objective of this work has been the development of new fire retardant thermosettings systems, keeping the material properties and environmentally friendly. The goals is to improve the good properties of some standard materials, phenolic and epoxy resins, but introducing the non inflammability character by means of new ignifugation systems, based on phosphorous and nitrogen, alternative to the classic halogenated systems widely used at the present time. The synthesis and characterization of novolac resin systems modified in different proportions with benzoxazine rings, using a new synthetic method based on the use of 1,3,5-triphenilhexahydro-1,3,5-triazine has been carried out. Their thermal behavior has been studied by differential scanning calorimetry as well as the influence that catalysts have in the ring opening reaction of benzoxazine rings. The thermal stability of these compounds has been studied using thermogravimetric analysis under nitrogen and air atmosphere. These systems show good thermal stability, and the chemical modification seem not to influence the thermal properties. Materials with good mechanical integrity have been obtained from the novolac-benzoxazine resins. Dynamomechanical analysis allowed us to establish qualitative relationships of crosslinking density and modification degree. V-O and V-1 were obtained when the materials were tested to according to the UL-94 V flammability test.
Moreover, in this work, two epoxyphosphorated compounds have also been synthesized to modify novolac and novolac-benzoxazine systems and to study its thermal, mechanical and fireproof properties: 10-(2,3-epoxypropyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPOGly), and an aliphatic diglycidilic compound that contains phosphine oxide moieties in its structure, isobutylbis(glycidylpropylether) phosphine oxide (IHPOGly). These glycidylic compounds do not contain hydrolytically unstable bonds and possess phosphine oxide moieties in their structure. Novolac and novolac-benzoxazine resins crosslinked with DOPOGly and IHPOGly lead to systems with different phosphorous content and different crosslinking density. By means of thermogravimetric analysis it has been shown that the incorporation of C-P bonds in these systems diminishes their thermal stability. Moreover the char yield at 800ºC increased with the phosphorous content under air atmosphere, while it do not undergo significative changes under nitrogen atmosphere. Novolac-epoxy phosphorated systems show lower degradation rate at high conversion degrees than the non-phosphorous systems according to the formation of an intumescent char. The novolac-benzoxazine-epoxy systems show a complex decomposition mechanism that cannot be related to the presence of phosphorous. Like in novolac-benzoxazine systems, for the novolac-benzoxazine-DOPOGly systems we have been able to establish qualitative relationships of crosslinking levels. For novolac-IHPOGly and novolac-benzoxazine-IHPOGly systems the glass transition temperature have been measured by DMA. Moreover secondary relaxations that have been observed and related to the chemical structure of the materials. Finally, the addition of organophosphorated compounds to novolac and novolac-benzoxazine systems improves its flame retardancy and degrees V-0 according to the UL-94 V test have been reached.
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Chaplan, Cory A. "Stabilization of Horseradish Peroxidase Using Epoxy Novolac Resins for Applications with Microfluidic Paper-Based Analytical Devices." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1252.
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Microfluidic paper-based analytical devices (microPADs) are an emerging platform for point-of-care diagnostic tests for use by untrained users with potential applications in healthcare, environmental monitoring, and food safety. These devices can be developed for a multitude of different tests, many of which employ enzymes as catalysts. Without specialized treatment, some enzymes tend to lose their activity when stored on microPADs within 48 hours, which is a major hurdle for taking these types of devices out of the laboratory and into the real world. This work focused on the development of simple methods for stabilizing enzymes by applying polymers to chromatography paper. The longterm stabilization was exlored and SU-8 of various concentrations was found to stabilize horseradish peroxidase for times in excess of two weeks. A variety of microPAD fabrications, enzyme dispensing methods, and substrate delivery techniques were explored.
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Borges, Sandro Gasparetto. "Síntese e caracterização de resinas fenólicas líquidas do tipo novolaca aplicáveis no processo de pultrusão." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/29362.
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Neste estudo foram investigadas as reações de síntese e cura de resinas fenólicas líquidas que são empregadas na fabricação de perfis reforçados com fibra de vidro utilizando o processo de pultrusão. Reações químicas envolvendo o fenol e o formaldeído foram realizadas em laboratório com o objetivo de produzir resinas fenólicas líquidas do tipo novolaca cuja viscosidade fosse em torno de 700-2000 mPa.s variando-se o tipo de catalisador ácido e o agente de cura. As resinas fenólicas obtidas foram submetidas a análises por Espectroscopia de Infravermelho por Transformada de Fourier (FTIR), Termogravimetria (TGA), Calorimetria Exploratória de Varredura (DSC), Colorimetria, Viscosimetria, Tempo de Gel, Tempo de cura e Flamabilidade. Além disto, também foram avaliadas a reatividade e a processabilidade destas resinas. Os resultados obtidos foram comparados com aqueles adquiridos para uma resina fenólica comercial do tipo resol. Verificou-se que as resinas novolacas produzidas neste trabalho são mais estáveis quimicamente do que a resol comercial. Além disto, as resinas novolacas obtidas apresentaram a gelificação em um período de tempo menor, favorecendo assim, o aumento na velocidade da reação de cura destas resinas. A análise por TGA mostrou que as resinas novolacas possuem estabilidade térmica e temperatura máxima de degradação superior à resina comercial empregada tornando-as mais adequadas para serem utilizadas no processo de pultrusão. O teste de flamabilidade mostrou que ambas resinas são auto-extinguíveis, correspondendo às especificações da norma UL-94. Através dos resultados obtidos neste trabalho, verificou-se que é possível desenvolver resinas fenólicas líquidas do tipo novolaca de baixo custo, que atendem as exigências do mercado nacional e que são adequadas ao processo de pultrusão.The synthesis and cure reactions of liquid state phenolic resins used in the production of profiles reinforced with glass fiber using the pultrusion process has been investigated. Chemical reactions involving phenol and formaldehyde were carried out at the laboratory with the aim of producing liquid state novolac type phenolic resins whose viscosity was about 700-2000 mPa.s varying the acid catalyst type and the cure agent. The phenolic resins were submitted to analyses of Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry (TGA), Differential Scanning Calorimetry (DSC), Colorimetry, Viscosimetry, Gel Time, Curing Time and Flamability. Besides, the reactivity and the processability of these resins were also investigated. The results were compared with those acquired for a commercial resol type phenolic resin. It was verified that the novolac resins obtained in this work are chemically stabler than the commercial resol. Also, the liquid state novolac type phenolic resins completed its gelification reaction in a smaller time, increasing, therefore, the cure reaction rate of these resins. The TGA analysis showed that the novolac resins possess higher thermal stability and maximum temperature of degradation than the commercial resin which assures its use in the pultrusion process. The flamability test showed that both resins are self-extinguishing, complying with the specifications of the UL-94. Through the results obtained in this work, it is possible to develop liquid state novolac type phenolic resins with low cost, which attends the demands of the national markets and is proper to the pultrusion process.
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Vazquez, Novoa Nadia [Verfasser]. "Data Envelopment Analysis: From Normative to Descriptive Performance Evaluation / Nadia Vazquez Novoa." Frankfurt a.M. : Peter Lang GmbH, Internationaler Verlag der Wissenschaften, 2017. http://d-nb.info/1137447702/34.
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Alves, Carlos Roberto. "Sintese de resina fenolica tipo resolica a partir de residuos da fabricação de resina novolaca : aplicação como adesivo." [s.n.], 1996. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267517.
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Orientador: Lucia H. Innocentini MeiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-07-22T11:10:20Z (GMT). No. of bitstreams: 1 Alves_CarlosRoberto_M.pdf: 3618168 bytes, checksum: 32092b441508dbb5bb1aea883aac948d (MD5) Previous issue date: 1996
Resumo: Nesse trabalho foram sintetizadas resinas fenólicas do tipo resol, a partir da reação de condensação entre o fenol, formol e um resíduo, proveniente da extração de solventes da fabricação da resina fenólica do tipo novolaca. As colas feitas com essas resinas foram avaliadas através do ensaio da faca (knif-test) e através do ensaio mecânico de cisalhamento do compensado. Os resultados obtidos foram comparados com os resultados de uma resina padrão. As resinas foram caracterizadas por espectroscopia de infravermelho, e por cromatografia de permeação em gel. Os benefícios em se utilizar o resíduo na síntese da resina fenólica é devido à redução do custo de fabricação e também o de evitar que o mesmo venha a poluir o meio ambiente. Um bom adesivo para o compensado foi obtido com o uso limitado do resíduo. Os melhores resultados foram obtidos, utilizando 15% de resíduo, na composição total de matéria prima da resina. O resíduo aumenta o peso molecular da resina, porém não contém os grupos de metilol e consequentemente diminuem as ligações cruzadas e retarda a cura da resina
Abstract: The work presented here concerns the synthesis of a phenolic resin throught the condensation reaction of phenol-formaldehyde with a residue that comes from a solvent extraction of novolaca phenolic resin. Glue made with these resins were evaluated with knife-test and mechanical plywood shear tests. The results were compared with that of a standard resin. The resins were characterized by using infrared spectroscopy and a gel permeation cromatography. The benefits of make use of this residue for phenolic resin sinthesys is due to reduce the cost of fabrication and avoid to pollute the environment. A good adhesive for the plywood bond were got with a limited use of the residue. The best result were obtained using 15% of residue based on phenolic resin raw material. This residue increase the resin molecular weight but it contains no reactive methylol groups and consequently it decrease the resins crosslink and hold up the resin harden
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química
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Segura, Novoa Rommel David [Verfasser], and Matthias [Akademischer Betreuer] Graw. "Occupant protection design with FE human body models / Rommel David Segura Novoa ; Betreuer: Matthias Graw." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1182228232/34.
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Novoa, Henríquez Catalina [Verfasser], Ulrich [Akademischer Betreuer] Schwaneberg, and Lars Mathias [Akademischer Betreuer] Blank. "Protein engineering of laccases towards higher pH / Catalina Novoa Henríquez ; Ulrich Schwaneberg, Lars Mathias Blank." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1195446535/34.
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Horák, Jan. "Kontaminace rizikovými prvky na Kutnohorsku a možnosti jejího využití v paleoenvironmentálním výzkumu." Doctoral thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-259654.
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The dissertation focuses on topic of using risk elements contamination as a stratigraphic marker in palaeoenvironmental research. The contamination is not studied only as itself, but is viewed as a way to analyse and interpret the sedimentary record of historical events. The contamination carries the information about its original place, its original activity, about development of the landscape.
The Kutná Hora region (central Bohemia; 49°57'0.170"N, 15°15'59.877"E) is a region of important historic mining and smelting activity. The mining started in 13th century and lasted until half of 16th century. Then only sporadic attempts of renewal were made. Spatially limited mining was renewed in second half of the 20th century. Therefore, it is highly probable to find here the contaminants in the role of stratigraphic markers. In the research were used mainly As, Be, Cd, Co, Cr, Cu, Hg, Pb, V and Zn as these are the most analysed in contamination studies performed in the region.
The aims of the dissertation were to answer these questions:
To characterize the contamination
- Are some risk elements typical for the contamination originating from the mining and smelting?
- If so, is their environmental (spatial, sedimentary) manifestation diversified?
- Is possible diversity spatially related to particular landscape features or areas?
- Is possible diversity connected to particular activities?
To use the answers in analysis of particular sites
- Is it possible to use the risk elements contamination as stratigraphic marker in fluvial sediments?
- How is the interpretation of particular site influenced by the whole context of regional contamination?
The core of the research is the metaanalysis of contamination data coming from region (the data obtained by our research and also from other studies). The results have brought not only basic characteristics of contamination, mainly concentrations. The crucial result was the structure of studied elemental complex. Only As, Cd, Cu, Pb and Zn are connected to contamination originating in mining and smelting. Other elements - their concentrations and spatial distributions - are uninfluenced by mining and smelting activities. More, the information about connection of As and Cd to mining and Cu, Pb and Zn to smelting was revealed. Both groups recorded with different spatial distributions. Also comparison of results by different approaches has shown that some statistical processing (clr-transformation) of such dataset was much better for interpretation than analyses of only concentrations values.
We studied also the area of confluence of two rivers - Klejnárka (main river draining contaminated region), which is tributary to Labe (Elbe) river. The contamination is still recognizable here, but the diversity between contamination elements is not. The confluence of rivers strongly dilutes the contaminated material. The concentrations decrease. Also here clr-transformation of data enabled to analyse structures of contaminants spatial distribution unrecognizable by concentrations values.
We performed also two vertical profiles analyses. It was shown, that it is highly risky to interpret data of such origin without the complex information about regional contamination context. It was revealed by contextual interpretation of data from one of the profiles, that there is a mixing of geochemical data coming from different statistical populations. The contamination works there as only one of the factors influencing sedimentary record. The site is therefore suitable for statistical testing of two populations mixing, outliers` detection and the like.
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Novoa, Sepúlveda Carla Alejandra [Verfasser]. "Flora and vegetation of the Olivillo Forest Region (Lapagerio roseae - Aextoxiconetum punctati Oberdorfer 1960) in the Valdivian coastal landscape, Chile / Carla Alejandra Novoa Sepúlveda." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/118390701X/34.
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Leyva, Novoa Veronica [Verfasser], Leticia [Akademischer Betreuer] Gonzalez, and Benjamin [Akademischer Betreuer] Dietzek. "The excited state intramolecular hydrogen transfer mechanism of ortho-Nitrobenzaldehyde : a quantum chemical and molecular dynamics study / Veronica Leyva Novoa. Gutachter: Leticia Gonzalez ; Benjamin Dietzek." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2012. http://d-nb.info/1019970030/34.
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Nordt, Sawa. "Analytik von Novolak-Epoxidharzen für die Resistentwicklung in der Mikrosystemtechnik." Phd thesis, 2010. https://tuprints.ulb.tu-darmstadt.de/2361/1/Dissertation_SawaNordt.pdf.
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Novolak-Epoxidharze, die zur Herstellung von Negativ-Photoresisten für die Materialstrukturierung mittels Lithographie verwendet werden, weisen aufgrund der verwendeten Syntheseverfahren eine breite Molekulargewichts- und Funktionalitätsverteilung auf. Diese erhebliche molekulare Heterogenität beeinflusst die Anwendungseigenschaften und die Reproduzierbarkeit der lithographischen Strukturierungsprozesse. Ziel dieser Arbeit waren Methodenentwicklung zur vollständigen Charakterisierung eines Negativ-Photoresists sowie deren Hauptkomponente, des Novolak-Epoxidharzes, um Struktur-Eigenschafts-Beziehungen für die Röntgenlithographie zu erstellen. Zur Charakterisierung des verwendeten Negativ-Photoresists, der lithographisch erhaltenen Strukturen als auch des Verhaltens des Resists während der lithographischen Prozessierung wurden neben chromatographischen auch spektroskopische und thermische Analysemethoden verwendet. So konnten entsprechende Parameter bestimmt und der Härtungsmechanismus genauer untersucht werden. Reisteigenschaften wie Flexibilität, Härte, Glasübergangstemperatur und Löslichkeit korrelieren mit dem Molekulargewicht des verwendeten Epoxidharzes. Zur Untersuchung des Molekulargewichtseffekts auf die lithographischen Ergebnisse wurden durch präparative Lösungs-Fällungs-Fraktionierung Epoxidharzfraktionen unterschiedlicher Molmasse hergestellt. Diese wurden mit Hilfe chromatographischer als auch massenspektroskopischer Methoden bezüglich ihrer Molmassen- und Funktionalitätsverteilung charakterisiert. Dabei hat sich gezeigt, dass bestimmte Oligomeranteile einen positiven Einfluss auf die röntgeninduzierte Netzwerkbildung des Materials zeigen. Daraufhin wurde eine Möglichkeit gefunden, den Negativ-Photoresist chemisch so zu optimieren, dass dieser sehr gute und reproduzierbare Strukturierungsergebnisse in der Röntgenlithographie zeigt.
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Lin, Hsiung-Min, and 林勳銘. "The effect of X-ray irradiation on the DNQ-Novolak type photoresist." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/09397553232054004433.
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碩士國立交通大學
工學院碩士在職專班半導體材料與製程設備組
95
With the flourishing development of photolithographic technology，it allows semiconductor technology to design more circuits in same area。Hence，faster，more multifunction and bigger capacity electronic products are available。The photoresist playing the key role in photolithographic technology is getting brand-new development from earlier broadband to now divided to optical and non-optical technology，the optical trend has been developed from 436nm and 365nm，gradually toward to short wavelength such as X-ray。However，to find out appropriate resist is a major problem。In this study，we used the DNQ/Novolak photoresist that is used in 365nm wavelength instead of PMMA resist used in X-ray，From experiment，it figure that the exposure energy of the X-ray is the factor to decide the resist is positive or negative under low dosage of X-ray，the resist thickness will be decreased with increasing energy，the developer will be finished working at a certain time when some critical line is arrived，it`s so called Eo。The Novolack resin will be breakdown to produce free radical to make cross-linkage by high dosage of X-ray，the cross-linkage will enhance the inner strength and lower the solubility in developer；if used appropriate developer，aims and the negative resist would be produced. The purpose of this article is to make fine DNQ/Novolak to proceed and evaluate the effect by photolithographic procedure，and to discuss the images and analyze the features of photoresist under various kinds of exposure dosages。
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ZENG, ZHAO-HUI, and 曾朝輝. "Study of silicic acid of esters of novolak as a postive photoresist." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/89652920997722652720.
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Nordt, Sawa [Verfasser]. "Analytik von Novolak-Epoxidharzen für die Resistentwicklung in der Mikrosystemtechnik / eingereicht von Sawa Nordt." 2010. http://d-nb.info/1009170953/34.
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Eisenheld, Leopold. "Measuring the adhesive bond quality of vinyl ester-glass composties on novolak hmr treated wood /." 2003. http://www.library.umaine.edu/theses/pdf/EisenheldL2003.pdf.
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Lin, Hao-Jie, and 林豪傑. "Study on the Siloxane Modified Novolac Type Phenolic Resin." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/24802378772790280818.
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碩士國立清華大學
化學工程學系
87
The objective of this study is to improve the toughness and the thermo-oxidative resistance of the cured Novolac type phenolic resin modified with polysiloxane. In order to improve the miscibility between Novolac type phenolic resin and polysiloxane, poly-(dimethylsiloxane adipamide) ( PDMSA ) were synthsized. By the addition of amide group in the main chain, strong intermolecular hydrogen bonding interaction was formed, consequently, the miscibility between Novolac type phenolic resin and polysiloxane was improved. The subjects of this study include the synthesis of PDMSA, miscibility between Novolac type phenolic resin, the improvement of toughness of PDMSA modified Novolac type phenolic resin and the improvement of thermo-oxidative resistance and flame resistance properties.From the experimental results, the predicted structure can be synthesized by reacting 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyl-disiloxane with adipic acid to form amide (nylon) salt, then was polymerized by melting reaction at 160 oC. By the investigations of IR, H1-NMR and C13-NNR, the molecular structure can be identified.Differential scanning calorymetric (DSC) and Infrared spectroscopic results show that there are strong intermolecular hydrogen bonding interactions existed between Novolac type phenolic resin and PDMSA. In the low PDMSA content regions, Kwei equation is feasible to the experimental Tg data; however, in the region between 30 wt.%~70 wt.% of PDMSA contents , the experimental Tg data closed to the prediction by Gordon-Taylor and Fox equations. furthermore, DSC results show great miscibility between Novolac type phenolic resin and PDMSA.TGA results of uncured Novolac/PDMSA blends show that PDMSA improves the thermo-resistance property of Novolac type phenolic resin at low temperature region, while Novolac type phenolic resin improved thermo-resistance property of PDMSA at high temperature region.Novolac type phenolic resin blended with PDMSA was cured by DGEBA type epoxy resin and using DBU as promotor The mechanical properties (include flexural strength, flexural modulus and Notched Izad impact strength) of Novolac type phenolic resin modified by PDMSA show great improvement. The flexural strength of cured resin specimen contains 5 phr PDMSA is 66% higher than that of neat phenolic resin. Flexural modulus of cured resin specimen contains 5 phr PDMSA is 3.6 times that of neat phenolic resin. Notched Izod impact strength of cured resin specimen contains 5 phr PDMSA is 37% higher than that of neat phenolic resin.TGA results of PDMSA modified Novolac penolic resin cured specimen in air show two step degradation. The addition of aliphatic chain of PDMSA to phenolic resin will decrease the first step degradation temperature of the cured resin specimens; however the siloxane chain will increase the second step degradation temperature.The flame resistance of the PDMSA modified novolac type phenolic resin cured specimens of UL-94 shows V-1 and its L.O.I is 35, which exhibit good flame resistance properties.
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Lee, Chih-Tsung, and 李志聰. "Study on the thermoplastiv resins toughened novolac type phenolic resin." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/60458711532526791313.
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HUANG, GUO-WEI, and 黃國維. "A study on the curing behavior of silylated novolac resins." Thesis, 1988. http://ndltd.ncl.edu.tw/handle/41467175965801140996.
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Liu, A. Y., and 劉安湧. "Curing and Pyrolysis of Cresol Novolac Epoxy Resins Containing ODOPN." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/70797750629237802358.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
90
In this paper, discussions of the kinetics in curing reaction of epoxy resin with a curing agent containing phosphorus, and the thermal degradation behavior, flame-retardant property of the cured epoxy resins. The curing reaction of a o-Cresol Novolac Epoxy (CNE) coupled with a curing agent containing phosphorus, 2-6(-oxido-6H-dibenz(c,e)(1,2)oxaphosphorin-6-yl)-1,4-naphthalenediol (ODOPN) was conducted to obtain an epoxy resin containing phosphorus in main chain. The kinetic parameters, activation energy of the curing reaction were obtained by DSC analysis. The glass transition temperature of the phosphorus content in cured phosphorus epoxy resins was measured by DMA. The thermal degradation behavior of cured phosphorus epoxy resins with different content of phosphorus was examined by TGA analysis. The residue in 700℃ by TGA was increased, and the degradation temperature will decrease by increasing phosphorus contents. The thermal degradation energy of cured phosphorus epoxy resins was estimated by Ozawa method, the energy was decreased by increasing phosphorus content in cured phosphorus epoxy resins. The flame-retardant property of cured phosphorus epoxy resin was measured by LOI. The LOI value was increased by increasing phosphorus content in cured phosphorus epoxy resins.
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Cheng, Chi-Yao, and 鄭棋耀. "Curing and Pyrolysis of Cresol Novolac Epoxy Resin Coating BABODOPN." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/39940661099349622784.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
92
In this paper, we investigated the curing kinetics reaction of epoxy resin with a curing agent containing phosphorus and nitrogenous. In addition and the thermal degradation behavior and flame-retardant properties of the cured epoxy resins were also investigated.. The curing reaction of a o-Cresol Novolac Epoxy (CNE) coupled with a curing agent containing, 1,4-bis(3-aminobenzoyloxy)-2-(6-oxido-6h-dibenz
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Tseng, Han-Thing, and 曾漢性. "Study on the polyester polyol modified novolac type phenolic resin." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/91740560764805452889.
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Huang, Chao-Chien, and 黃昭謙. "Studies on the Organic-Inorganic Hybrid Nanocomposites of Cresol Novolac Epoxy." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/46966270042018368263.
Full textAbstract:
碩士國立高雄應用科技大學
化學工程系碩士班
93
The organic-inorganic hybrid nanocomposites of Cresol Novolac Epoxy/silica were successfully prepared by two approaches in this study. One approach was the sol-gel process with Cresol Novolac Epoxy (Part I). Another was the melting intercalation process (Part II). In Part I, the silica were prepared by the hydrolysis and condensation of methyltrimethoxysilane(MTOS) and 3-Glycidoxypropyltrimethoxysilane(GPOS) as precursors. Meanwhile, GPOS were also used as coupling agents in systems. The results show that when silica content was lower than 3 wt% in the hybrid, the particles sizes of silica was lower than 100 nm. Nevertheless, the particles sizes of silica can be controlled by adding coupling agent in system. The glass transition temperature and dielectric properties of Cresol Novolac Epoxy were obviously improved with silica embedded. In Part II, montmorillonite clay modified with the cetylpyridinium chloride(CPC) was used to prepare the Cresol Novolac Epoxy/clay hybrid nanocomposites. The types of morphology (exfoliated or intercalated structure) in the hybrid nanocomposites were successfully controlled by melting the epoxy resin to vary the viscosity for shearing the clay into the epoxy resin. In this study, we are also successfully to create the exfoliated structure at the high clay loading and the intercalated structure at the low clay loading by using the different surfactants.
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LIN, CHUN-TE, and 林俊德. "Preparation and properties of novolac phenol formaldehyde resin for grinding materials." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/01388412697386959104.
Full textAbstract:
碩士萬能科技大學
材料科技研究所
97
In this thesis, novolac-type phenolic resins with various molecular weights and with various concentrations of hardener under different curing temperatures were prepared. Instead of the generally used inorganic acid catalyst (hydrochloric acid) for phenolic resin that used for molding material, organic acid catalyst (oxalic acid) was used in the synthesis of our phenolic resins. The physical and thermal properties of the resultant phenolic resins were also examined. Phenolic resins with various molecular weights were obtained by changing the phenol/ formaldehyde molar ratio in the synthesis process. In addition, various amounts of hardener (hexamethylene-tetramine) were mixed with the phenolic resin to study the effect of hardener on the various properties of phenolic resins. Fundamental properties as flow length, gel time and softening temperature of the phenolic resins with various molecular weights and concentrations of hardener were measured. Also, structure of these phenolic resins was identified through FTIR and GPC measurements. Thermal properties of these phenolic resins were investigated through TGA and DSC measurements. Finally, various grinding tools were prepared from these phenolic resins using various curing temperatures. The mechanical properties as flexural and impact strengths of the grinding tools were also examined. The above-mentioned measurements can evaluate the effects of molecular weight, hardener concentration and curing temperature on the physical and thermal properties of these phenolic resins. As a result, high physical property and good heat-resistant phenolic resin was obtained by increasing the molecular weight or by incorporating 12 wt% hardener and curing the phenolic resin at 180℃ or 190℃. On the other hand, fragile phenolic resin was obtained by incorporating 4 or 20 wt% hardener and curing the phenolic resin at 190℃ or 200℃. Results of this thesis provide valuable information for application of the powdery novolac-type phenolic resins.
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YEN, WU JUNG, and 吳榮晏. "Investigation on Low Dielectric Novolac Epoxy Resin and its Composite Laminate." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/45373468863885469502.
Full textAbstract:
碩士長庚大學
化學工程研究所
89
In this experiment, new novolac resin Cyclohexylphenol (CHP) and commercial Butylphenol are synthesized and reacted with formaldehyde, and then the CHP novolac resin and Butylphenol novolac resin will be reacted with Epichlorohydrin (ECH) to product Cyclohexylphenol Epoxy Resin and Butylphenol Epoxy Resin in addition polymerization. According to the specific proportion of CHP Epoxy Resin, hardener (BPA-PN) and retardant (TBBA), which are blended and mixed uniformly to form Vanish. Glass Fiber Cloth will be immersed in Vanish, and then dry the Glass Fiber Cloth coated Vanish to manufacture prepreg at high temperature. To repeat the step, we will get the same six layers of prepregs. Folding six prepregs, and then to heat press them to manufacture laminate. According to the results of dielectric characteristics of FR-4 laminate and Cyclohexylphenol Epoxy Resin Laminate and Butylphenol Epoxy Resin Laminate, the average dielectric constantεr of Cyclohexylphenol Epoxy Resin Laminate and Butylphenol Epoxy Resin are about 4.0 and 4.2, that are lower than FR-4 laminate which average dielectric constant is about 4.8. The dielectric loss tangent of Butylphenol Epoxy Resin Laminate and Cyclohexylphenol Epoxy Resin Laminate and FR-4 Laminate are 0.08, 0.01 and 0.03. So, the Butylphenol Epoxy Resin Laminate consumed maximun Energy and the Cyclohexylphenol Epoxy Resin Laminate consumed maximum Energy.
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Wang, Ko-Yuan, and 王科元. "Preparation And Characterization of Novolac Cured Epoxy/Carbon Nanocapsules Modified Clay Nanocomposites." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/15436767427978003066.
Full textAbstract:
碩士中原大學
化學研究所
98
Abstract In this study、the dispersed template of clay were modified by different types of fullerene materials、such as carbon nanocapsules as one of intercalants. The enhanced effects of fire retardant come from clays with barrier and fullerene with free radical capture. Clay were modified by organic compounds and carbon nanocapsules (CNC). The modified clays were characterized by wide-angle X-ray diffraction (WAXD)(d-spacing Increase to 15.3 A and 14.7A)、thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FT-IR) to confirm the inclusion of modified agent into clay layers. The dispersion morphology of clay in the novolac cured epoxy resin was analyzed by wide-angle X-ray diffraction (WXRD) (d-spacingPCB-3%=15.19A、MCB-1%=15.5A、MCB-3%=10.00A is clay Characteristic) and transmission electron microscopy (TEM) (result find PCB-3% intercalated，MCB-1% and MCB-3% is Reunion).Thermo-gravimetric analysis (TGA) (Inserts the quantity PCB=33.28%，MCB=24.2%) and dynamic mechanical analysis (DMA) (Tg Temperature PCB-0.5%=144.5℃，PCB-1%=156.6℃ PCB-3%=141.4℃) were used to study the thermal and mechanical properties of modified novolac epoxy. Finally、limiting oxygen index (LOI))(MCB-0.5%=26%，MCB-1%=26%MCB-3%=27%)and cone calorimeterr(HRR) (Combustion time late to 160 sec) test were applied to evaluate the flammability of these nanocomposites of modified novolac epoxy.
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葉德傑. "The Dielectric Properties of Cresol Novolac Epoxy(CNE)/Aramid Paper Composite Laminates." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/94691518206740422872.
Full textAbstract:
碩士義守大學
生物技術與化學工程研究所
92
The cresol novolac epoxy/phenolic novolac hardener system was used here as the matrix material for epoxy/aramid paper printed circuit board applications. A siloxane modifier was incorporated into the epoxy matrix by using an interpenetrating polymer network technique to improve its hygrothermal properties. Dielectric and dynamic properties were measured for these epoxy/aramid composite laminates of various compositions. The dynamic dielectric constants such as permittivity and loss factor were found to increase with increasing aramid paper loading at high temperatures. At low temperatures(＜80℃) and high frequencies(＞1Hz), the loss factor of epoxy/aramid composites was decreased. As for the dynamic mechanical properties, the storage and loss moduli were found to increase with increasing aramid paper contents, but the tanδ was inverse, the tanδ decreasing with increasing aramid paper loading. The coefficient of thermal expansion and volume resistivity of the composite also increased with increasing aramid paper content.
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Chu, Chien-Fang, and 朱建芳. "Properties of Novolac/Epoxy Alloy Resins Prepared from Liquefied Cryptomeria Japonica Wood." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/25708669825372834331.
Full textAbstract:
碩士國立中興大學
森林學系所
102
In this study, Cryptomeria japonica (Japanese fir) was liquefied in phenol or phenol/bisphenol A with H2SO4 as catalyst. Novolac-type phenol-formaldehyde resins (PF) were synthesized by reacting liquefied wood or phenol with formalin. Epoxy resin was prepared by reacting bisphenol A with epichlorohydrin. The polyblending resins were prepared by mixing PF with epoxy, and the epoxidized novolac-type PF resins were prepared by reacted with epichlorohydrin. The curing behavior and the properties of moldings for alloy resins with various cross-linking agents were investigated. The results show that novolac-type PF resins had the behavior of hot-melting and could be hot-thermosetting when mixing with hexamethylenetetramine (hexamine). DSC analysis showed an exothermic peak due to crosslinking reaction for epoxy resin that mixed with triethylene tetramine (TETA), hexamineand maleic anhydride (MA). Novolac/epoxy polyblending resins could be hot-setted when triphenylphosphine was added as a catalyst. Additional adding of hexamine could promote the reactivity of thermosetting, and further adding of TETA could lead the curing reaction occured at room temperature. The cured polyblending resins had good dimensional stability after dissolution test and had higher heat resistance. It had better high temperature resistance for that blended with liquefied wood-based novolac-type resin. Moldings made with polyblending resins by adding hexamine had better weight retention and lower heat activities. Epoxidized PF resins that cured with TETA/hexamine mixture as the hardener had better weight retention. The heat resistance of novolac-type resin could be improved after epoxidized, and it could advance be increased by the components of lignocelluse. Molding could be made with the mixture of epoxidized PF resins, wood powder, hexamine, TETA and zinc stearate under hot-pressing. They had higher weight retention after acetone dissolution test than that made with unepoxidized novolac-type resins.
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Chen, Chih-Yuan, and 陳致源. "Study on Thermoplastic Polymer Modified Novolac Type Epoxy Resin Derived Carbon/Carbon Composite." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/58681941866263544402.
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碩士國立清華大學
化學工程學系
89
In this study, modified novolac type epoxy resin has been used as a new matrix precursor to fabricate C/C composites. The polydimethylsiloxane polyurethane synthesized was used as a modification agent. Novolac type epoxy has almost the same chemical structure as phenolic resin, however, it possesses the epoxied functional group that is easy to react with the modification agent. The modification system utilized is polydimethylsiloxane polyurethane(PDMS-PU) which protects the fiber surface and improves the thermal stability of matrix. PDMS-PU was synthesized in this study and it structure was confirmed by IR and NMR. Results show that modified epoxy with low content(<10phr) of PDMS-PU is miscible, the PDMS-PU can completely disperse in the epoxy matrix and decrease the glass transition temperature and crystallinity of novolac type epoxy. In the study of curing kinetics, it was found that the content of PDMS-PU will affect the collision factor, total heat of reaction and the active energy of reaction. In order to achieve the modification purpose, the first step is utilizing novolac type epoxy resin to derive carbon/carbon composite instead of using phenolic resin. Different post curing times and temperatures, and different carbonization heat treatment temperatures were applied to the novolac type epoxy resin. Results show that the matrix cured at a higher post-curing time and temperature exhibits a significantly weight loss on the post curing process and limits the weight loss on carbonization processing. In the modified composite system, results show that the flexural strength of composite after post curing process will be reduced when the PDMS-PU content increase because of the flexible molecular structure. In the carbonization process, PDMS-PU will protect the fiber surface to prevent the intense shrinkage deriving from thermal degradation consequently, increase the flexural strength of C/C composite from 94.2Mpa to 106.9MPa after carbonization process. Oxidation testing result shows that PDMS-PU containing carbon/carbon composites exhibit better oxidation resistance and lower oxidation rate than those derived from pure epoxy resins. Increasing the post-cure time and temperature will improve the mechanical properties after carbonization. In the carbonization process, the mechanical properties and density decrease rapidly after 400℃. When heat treatment temperature rises up to 800℃ the mechanical properties and density will maintain constant and then increasing slightly. The mechanical property of the carbon/carbon composite made by epoxy resin was better than that of phenolic resin, and the flexural of composite strength was increased from 63.9MPa to 94.2Mpa.
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Huang, Hsien-Ping, and 黃賢平. "Study on the Flammability of Novolac Epoxy Resin／Graphene－Intercalated－Modified Clays Nanocomposites." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/28w9w3.
Full textAbstract:
碩士中原大學
奈米科技碩士學位學程
103
Functionalized inorganic layered material (clay) based on modification system composed by Benzalkonium-N-methyl pryrrolidine-graphene, were designed and fabricated in this study to synthesize novolac cured epoxy nanocomposites. Clays, as dispersed template, were modified by methyl pyridine functionalized graphene materials, such as multilayers and mono layer graphene intercalants. There are functionalized graphene materials to enhance the fire retardant of resulting nanocomposites. The functionalized graphene characterized by Raman spectroscopy, and thermo-gravimetric analysis (TGA) was applied to confirm the difference functionalities of graphene. The modified clays were characterized by wide-angle X-ray diffraction (WAXD), TGA and Fourier transform infrared spectroscopy (FTIR) to confirm the inclusion of modified agents into clay layers. The dispersion morphology of clay in the novolac cured epoxy resin was analyzed by WXRD and transmission electron microscopy (TEM). TGA and dynamic mechanical analysis (DMA) were used to measure the thermal and mechanical properties. Finally, limiting oxygen index (LOI) and cone calorimeter test were applied to evaluate the flammability of these nanocomposites. The best composites of modified clay/novolac cured epoxy nanocomposites were selected to make copper clad laminate (CCL) and discussed the properties and flammability. Consequence, 3wt% CL120-PI-BEN-OGNS-Epoxy nanocomposites has shown the best flammability. Apply this result to make the copper clad laminate which has passed the UL-94-V1 test.
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Li, Chih-Hung, and 李志宏. "Study for The High Performance Electronic Packaging Materials Based on Novolac-Clay Nanocomposites." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/g2qr2k.
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碩士中原大學
化學研究所
92
Abstract Printed circuit board（PCB）plays an important role in electronic products, and Copper Clad Laminate, called CCL, is one of the major components. CCL made by 3 stages as show blow. Stage A, the glass fiber is coated by epoxy slurry, which contains monomer、initiator、curing agent and solvent. Stage B, the coated glass fiber is cooked until preprag formation. Stage C, the preprag is covered with copper foil and post cured under pressure and degas. After etching copper foil and forming circuit map, the printed circuit board, applied to general electronic products, is made by single-sided CCL. For the application of industrial and communication devices, PCB is made by double-sided CCL. However, multilayer CCL is for the application of personal computer, communication device, automatic control equipment even for military or airplane. In this study, the applied clay, which intercalated with different types of curing agents, mixed with novalac resin, and prepared the novalac/clay nanocomposites. Therefore, the properties of CCL have been improved in CTE, water uptaken ratio, flame retardant, and thermal stability. These properties were identified by the analysis of TGA、DMA、DSC、PCT and LOI.
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Hsin, Tai, and 戴炘. "The Toughening Process and Properties of Novolac type Phenolic/SiO2 Flame Retardant Nanocomposite." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/97855687708204631341.
Full textAbstract:
碩士國立清華大學
化學工程學系
91
In this study, Polydimethylsiloxanes (hydroxyl group terminated) are used to toughen 3-Glycidoxypropyltrimethoxysilane (GPTS) modified novolac type phenolic resin / SiO2 organic/inorganic nanocomposite material via sol-gel method. Effects of polydimethylsiloxane on the physical, chemical, mechanical and thermal properties of nanocomposite material were discussed. The polydimethylsiloxanes with various molecular weights (MW = 400~700) were used. Moreover, due to the incompatibility of polydimethylsiloxane and GPTS modified novolac type phenolic resin, three coupling agents (3-Glycidoxypropyl trimethoxysilane, GPTS, 3-Isocyanatopropyl triethoxysilane, IPTS, Tetraethoxysilan, TEOS) were used to modify polydimethylsiloxane and the properties were investigated. From FT-IR spectra studies, it was found that the peak of hydroxyl group at the ends of PDMS is disappear at 3312 cm-1 and produced a new peak of C-O stretching at 1100 cm-1. It was also found that the peak of isocyanato group of IPTS disappeared at 2272 cm-1 and peaks of urethane group at 1680~1630 cm-1 and 1640~1550 cm-1 were shown. The peak of hydroxyl group at the ends of PDMS disappeared at 3312 cm-1 and split peaks at 1100 cm-1~1080 cm-1 can be seen. The split peaks are the absorption of C-O stretching and Si-O-Si antisymmetric stretching. It is confirmed that the three coupling agents (GPTS, IPTS and TEOS) are successfully modified PDMS. 29Si solid-state NMR spectra revealed that Q3, Q4 and T3 are the major environments for GPTS modified phenolic resin nanocomposite condensed with modified PDMS (less than 10 phr), i.e., it formed the network structure of Si-O-Si bonding. From thermal property study, the Td5 (Temperature of 5% weight loss) of GPTS modified phenolic resin nanocomposite condensing with GPTS modified PDMS decreased from 381℃ to 369℃, decreased from 381℃ to 362℃ for IPTS modified PDMS and increased from 381℃ to 401℃ for TEOS modified PDMS. From mechanical property study, the impact strength of GPTS modified phenolic resin nanocomposite which condensed with GPTS modified PDMS increased from 8.4kJ/m2 to 10.8 kJ/m2, increased from 8.4 kJ/m2 to 8.9 kJ/m2 for IPTS modified PDMS and increased from 8.4 kJ/m2 to 10.1 kJ/m2 for TEOS modified PDMS. The flexural strength of GPTS modified phenolic resin nanocomposite which condensed with GPTS modified PDMS increased from 77.2 MPa to 85.1 MPa, decreased from 77.2 MPa to 69.1 MPa for IPTS modified PDMS and decreased from 77.2 MPa to 72.4 MPa for TEOS modified PDMS. The L. O. I. values of all nanocomposite reached 35~38 and the U. L. values are 94V-0.
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Lu, Shau-Tai, and 呂紹臺. "Synthesis and Characterizations of Inorganic Layered Materials/Novolac Cured Resin Nanocomposites for Copper-Clad Laminar." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/28996189965325863274.
Full textAbstract:
博士中原大學
化學研究所
96
The research in this study is focused on two parts. The first part is preparations of intercalated or exfoliated novolac cured epoxy resin nanocomposites with layered silicates- (PK-805). The bi-functional modifiers (PI/BEN or MI/BEN) are used to modify the clays for improvement of the properties of polymer where benzalkonium chloride (BEN) acts as a compatibilizing agent and 2-phenylimidazole (PI) or 2-methylimidazole (MI) as the accelerators. Both the compatibilizer and accelerator (with different ratio) are simultaneously intercalated into the gallery space of pure clays to form the modified clay. The novolac cured epoxy-clay nanocomposites, which perform the well-dispersion of clay and the higher crosslinking density, are simultaneously mixing two modified agent with 5:5 mole ratios are intercalated into the clay instead of using single modified agent. The improvement in the dimensional stability is significant comparing to the pure epoxy polymer, which has the CTE of 62.23 ppm/℃ below Tg in the Z direction. In addition, the water uptake was decreased by 27.5%, i.e., from 0.64 to 0.40, and 0.52 % for PB/PK-805, and MB/PK-805 modified clays. On the other hand, different cation exchange capacity (72~300) meq/100g of modified clay/novolac cured epoxy nanocomposites are also discussed in this work (by using MB55 and PB55 as modifier). High CEC value is not good of the effect on dispersity, can decreasing of the Tg (crosslinking density) which as indicated by DMA. But the higher compatibility between epoxy resin and clay’s surface will induce the higher Tg. The properties of novolac cured epoxy/clay nanocomposites were characterized by wide-angle X-ray diffraction (WAXD), thermo-gravimetric analysis (TGA), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM) methods. According to the measurement, these novolac cured epoxy-clay nanocomposites have shown the significant improvement in the thermal, mechanical and barrier properties that are good for application of printed circuit board. The second part is for application of flame-resistance. The layered materials such as layered double hydroxides (LDHs) (Mg-Al and Li-Al LDH) were modified by 4,5-imidazole dicarboxylic acid and the natural clays (PK-802) were modified by N-methyl pryrrolidine-fullerene. XRD and TEM indicate the exfoliations of layered materials in the polymer matrix. The increasing LOI values were due to the addition of small amount of layered materials dispersed well in the polymer matrixes. The peak heat release rate falls incorporation of the amount of LDH, the PHRR is decreased from 364 to 319 kW/m. The total heat released is decreased from 98.67 MJ/m to 9.73 MJ/m in the case of Li-Al LDH-IM 3wt%, the average loss weight rate is decreased from 10.36 g/s to 3.96 g/s, the average heat release is decreased from 163.96 kW/m to 53.99 kW/m. The fire-resistance property of nanocomposite depends on the aspect ratio or the presence of hydroxyl group and the dispersity of layered materials. The LOI increases from 19 to 28, and Tg is increased form 124.1 to 148.5 and 131.3℃, respectively. This result suggests that the novolac cured epoxy/layered double hydroxide nanocomposites might apply to the circuit board with good fire-resistance property.
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HUANG, CHUN-CHIEH, and 黃俊傑. "Study on the Preparation and Characterization of Novolac CuredEpoxy/Clay Laminate Materials with Fire Resistant." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/59791406517979397996.
Full textAbstract:
碩士中原大學
化學研究所
96
The fire-resistance is one of the most important properties that need to pay much attention to improve the general electronic product. The halogenatedepoxy compounds are used in printed circuit board (PCB) to improve the thermal and fire resistant properties for mamy years. However, this kind of material produces large amount of smoke and toxic material like dioxin during combustion. It is necessary to replace the halogenated-epoxy to the novel organic-inorganic hybrid nanocomposites as far as the environmental pollution are concerned. Polymer/layered silicate nanocomposites (PLSNs) have been studied extensively since past two decades due to their outstanding improvement in the physical, mechanical, and chemical properties. Epoxy resin is commonly used to make the printed circuit board. If small amount of inorganic fillers such as clay or layer double hydroxide could be dispersed into the novolac cured epoxy resin, the properties might have been improved. This idea has encouraged me to prepare and study the novolac cured epoxy resin/layered material hybrid nanocomposites. The synthesis, characterization and properties of novolac epoxy resin/layered silicate nanocomposites have been discussed in this report. Montmorillonite clay (MMT) and Mg-Al-layered double hydroxide (Mg-Al LDH) are used as layered materials. At beginning, clays or LDHs are modified by long chain organic compound with cycloalkene backbone to increase the compatibility between the polymer and layered materials. The novolac epoxy resin/layered silicate nanocomposites are successfully prepared using these organically modified clay/LDH with novolac cured epoxy resin by in situ cross-linking polymerization method. The morphology of these nanocomposites was investigated by using wide angle X-rays diffraction (WAXD) and transmission electron microscopy (TEM) techniques. Thermo-gravimetric analysis (TGA) and dynamic mechanical analysis (DMA) were used to study the thermal and mechanical properties. Their combustion behavior has been evaluated using limiting oxygen index (LOI) and Cone calorimeter test. According to the measurement, these novolac cured epoxy-clay nanocomposites have been shown the significant improvement in the thermal, mechanical and barrier properties that may be applied to make printed circuit board.
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Chang, Dong-Meau, and 張東淼. "Studies on the Syntheses, Characterization and Applications of Polyurethane/Allyl Novolac Resin Cross-Linked Polymers." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/12622731087161354331.
Full textAbstract:
博士大同工學院
化學工程學系
84
Based on the inherently imcompatibile materials, polyurethane and phenolicresin, the object of this dissertation is to synthesize imhomogeneous network polymers by either interpenetrating network technology or AB crosslinked networkmethod. These novel network polymers would possess imhomogeneous structure and pertain enough mechanical strength, which may increase by the rigid structure of phenolic resin, for the demand of liquid/liquid separation membrane or biomaterials. There are five series polyurethan/phenolic resin network polymers with different network structure had been synthesized successfully. First of all, theallyl novolac resin was synthesized by substituted the hydroxy group in phenolicresin with allyl chloride for eliminating the interference reaction between polyurethane and phenolic resin. Thus, the first UT series SINs was synthesizedby SIN method to improve the compatibility between PU and Phenolic resin. Afterthe thoroughly studying by thermal analysis, dynamic-mechanical analysis, and morphological observation, the UT series still had phase separation evidently.Therefore, the improvement of grafting reaction carried out by implant the double bond into PU main chain, i.e., TMPME was used as the chain extender of PU.The resultant TUT series SINs provide better phase mixing but the mechanical strength also decrease simultaneously. For the requirement of superior mechanical strength and less phase separation, the epoxide group was used as thecrosslinking element in the PU network (UT-G series SINs). The resultant UT- Gseries SINs provide better mechanical strength, but the degree of phase separation was no clearly improved. The other modifying method was AB crosslinked network structure. Themethacrylamide and maleinimide had been used as end-capped compounds because of itshigh tensile strength and heat resistence, i.e., the UT-M series ABCPs and UT-I series ABCPs respectively. The experimental results reveal that those ABCPsnetwork polymers have better mechanical strength and phase mixing than that of the SINs specimens. The pervaporation separation experiment of benzene/n-hexane, or benzene/ cyclohexane had carried out by using the UT-M series ABCPs as separation membranes. It was concluded that those ABCPs membranes behave higher permeatingflux of benzene than that of toluene either in n-hexane or cyclohexane. Based onthose test results of pervaporation separation by UT-M series ABCPs, it is believed that the other series SINs or ABCPs would possess similar properties inpervaporation separation.
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Tien, Tsing-Zhe, and 田青哲. "Epoxy-modified novolac phenolic resin/phosphate glaze composites: preparation and use as diamond cutting tools." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/99013681562388100170.
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wu, wen jia, and 吳文嘉. "Study on the thermoplastic polymer modified Novolac type phenolic resin to prepare carbon/carbon composites." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/37054352860138676759.
Full textAbstract:
碩士國立清華大學
化學工程學系
87
The objectives of this study are utilizing thermoplastic polymer (poly(ethylene oxide, PEO)) to modify Novolac type phenolic resin and to prepare carbon/carbon composites.Different ratios of PEO were added to the Novolac type phenolic resin to fabricate carbon/carbon composites and to investigate the microstructure of carbon matrix of phenolic resin and the interface between resin matrix and carbon fiber. The mechanical properties (density, porosity, flexural strength and interlaminar shear strength), physical properties (toughness behavior, internal pressure build up) and degradation kinetic parameter (activation energy, frequency factor) of the composites before and after carbonization were studied.The wet-out between the carbon fiber and the matrix of the PEO modified novolac type phenolic resin after SEM photographs investigated curing. Apparently, the interfacial bonding between carbon fiber and resin matrix was improved significantly with the increasing of PEO content.The flexural strength of carbon/carbon composites precursor with 5 phr ( part per hundred parts of resin) PEO is 10﹪higher than that of specimen of neat phenolic resin. However, the density and the porosity do not change significantly. The flexural strength of carbon/carbon composites with 10 phr PEO is 40﹪ higher than that of specimen of neat phenolic resin. Although the density was decreased，the porosity was increased for carbon/carbon composites containing PEO. The existence of PEO will help to reduce the internal stress build-up and to enhance the flexural strength of the fabricated carbon/carbon composites.The interlaminar shear strength (ILSS) of carbon/carbon composites precursor with 10 phr PEO is 40﹪ higher than that of specimen of neat phenolic resin. PEO was added to improve the interfacial bonding between the matrix and the fiber. The interlaminar shear strength of carbon/carbon composites with 10 phr PEO is 10﹪higher than that of specimen of neat phenolic resin.The flexural strength and the density of the 2-D carbon/carbon composites densified via liquid resin reimpregnation process were increased with reimpregnation times. The flexural strength of carbon/carbon composites through four times densification process is 90﹪ higher than that of the undensified neat phenolic resin . The flexural strength of carbon/carbon composites with four times densification process is 18﹪higher than the undensified 10 phr PEO/phenolic resin system.For degradation kinetic parameter of PEO/phenolic resin system, thermoplastic polymer can reduce the maximum degradation temperature of phenolic resin with the increasing PEO content. The maximum weight loss by degradation also was increased with PEO content.
49
Sitetyana, Pindiwe. "An optimisation study into the synthesis of o-cresol novolacs." Thesis, 2008. http://hdl.handle.net/10210/422.
Full textAbstract:
The phenolic resin chemistry is an old chemistry that started in the late 1800’s. A lot of research work to gain understanding of phenolic resins has been done and reported in literature. However, most of the studies are based on phenol novolac resins. It was necessary to acquire more knowledge on specifically o-cresol novolac (OCN) resins because of the interest in the production of these resins. The chemistry in question was new to Sasol and one of the major objectives of doing this work was to build in-house competency in this field. This was achieved by first investigating whether the available feed materials containing certain impurities can be used to synthesise o-cresol novolacs with set specifications of purity and physical characteristics. The suitability of the Sasol o-cresol in terms of its contamination with sulfur (which is sometimes found in relatively higher amounts due to operating conditions) was investigated. The results showed that the sulfur in o-cresol did not have a significant contribution in the sulfur of the OCN. Another contaminant, formic acid, an auto-oxidation product found in formalin solutions was also investigated. It was also observed that, at formic acid levels of up to 4000 ppm, there was no effect on the softening point of the OCN. Secondly, it was important to study and understand the effect of different reaction variables on the quality of the OCN resins. The effect of formaldehyde: o-cresol molar ratio was investigated, the softening point increased with the increase in the molar ratio. The effects of other reaction variables (catalyst, reaction time, temperature and formaldehyde feed rate) on the softening point of the OCN were also investigated using p-toluenesulfonic acid and oxalic acid as catalysts. With p-toluenesulfonic acid as a catalyst, the temperature had no effect on the softening point, while all the other variables showed an effect on this parameter. A softening point model was formulated, which predicted the softening point with 98% accuracy. With oxalic acid, only the amount of catalyst had an effect. In addition, the chemical structures of these compounds were studied using 13C-NMR spectroscopy. The focus was on the isomer distribution of the methylene linkages.Prof. D.B.G. Williams
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Wu, Zi-Sheng, and 吳自勝. "The Study of Mechanical Properties for Composite Substrate of Cresol Novolac Epoxy/Polysiloxane/Nonwoven Aramid Paper." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/41198614024114491764.
Full textAbstract:
碩士義守大學
生物技術與化學工程研究所
92
The o-cresol-formaldehyde novolac epoxy (CNE)/phenolic novolac hardener system was used here as the matrix material for epoxy/nonwoven aramid paper printed circuit board applications. A siloxane modifier was incorporated into the epoxy matrix by using an interpenetrating polymer network technique to improve its hygrothermal properties. A low stress matrix resin was synthesized by adding the polydimethylsiloxane into CNE resin to form a simultaneous interpenetrating network (SIN). Nonwoven aramid papers were used to improve the laser-drilling processability. From tensile tests, it is found that the siloxane-modified resin is tougher than the unmodified one. Comparing to CNE resin, the modified resin has a lower Young’s modulus and a lower tensile strength, but a higher strain at break. After incorporation the nonwoven aramid paper, the mechanical properties would increase as compared with the neat resins. The level of water uptake for the modified resin is lower than that for the unmodified one (1.98 wt% vs. 2.22 wt%). The use of nonwoven aramid paper help to reduce the water uptake level for the composites. From sessile drop experiments, it is also found that the incorporation of the siloxane modifier into the epoxy matrix also lowers the surface tension value. SEM observations show that the adhesion between the resin and the paper for the siloxane-modified composite material are better than that for the unmodified one.