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Xu, Xiaolin. "Cellulose fiber reinforced nylon 6 or nylon 66 composites." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26487.
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Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2009.Committee Chair: John D. Muzzy; Committee Co-Chair: Youjiang Wang; Committee Member: Art Ragauskas; Committee Member: Donggang Yao; Committee Member: Karl Jacob. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Mukai, Uchu. "Mechanical properties of PDMS-nylon-6 diblock copolymer and its blends with homo nylon-6." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11454.
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Srinivas, Srivatsan. "Crystallization behavior of nylon 6/6 and it's [sic] blends with poly(vinyl pyrrolidone) /." This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09192009-040352/.
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Mohan, Anushree. "Modification of Nylon 6 Structure via Nucleation." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-07092009-181421/.
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For nearly two decades inclusion compounds (ICs) have been formed by threading polymer chains into the cyclic starches, cyclodextrins (CDs). Non-covalently bonded crystalline ICs have been formed by threading CDs, onto guest nylon-6 (N6) chains. When excess N6 is employed, non-stoichiometric (n-s)-N6-CD-ICs with partially uncovered and dangling N6 chains result. We have been studying the constrained crystallization of the N6 chains dangling from (n-s)-N6-CD-ICs in comparison with bulk N6 samples, as a function of N6 molecular weights, lengths of uncovered N6 chains, and the CD host used. While the crystalline CD lattice is stable to ~ 300° C, the uncovered and dangling, yet constrained, N6 chains may crystallize below, or be molten above ~225° C. In the IC channels formed with host α- and γ-CDs containing 6 and 8 glucose units, respectively, single and pairs of side-by-side N6 chains can be threaded and included. In the α-CD-ICs the ~ 0.5nm channels are separated by ~ 1.4nm, while in γ-CD-ICs the ~ 1nm channels are ~ 1.7 nm apart, with each γ-CD channel including two N6 chains. The constrained dangling chains in the dense (n-s)-N6-CD-IC brushes crystallize faster and to a greater extent than those in bulk N6 melts, and this behavior is enhanced as the molecular weights/chain lengths of N6 are increased. Furthermore, when added at low concentrations (n-s)-N6-CD-ICs serve as effective nucleating agents for the bulk crystallization of N6 from the melt. Because of the biodegradable/bioabsorbable nature of CDs, (n-s)-polymer-CD-ICs can provide environmentally favorable, non-toxic nucleants for enhancing the melt crystallization of polymers and improving their properties.
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Rotter, George Edmund. "Polymerization and crystal formation of nylon 6." Case Western Reserve University School of Graduate Studies / OhioLINK, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=case1054928542.
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Gaglione, Anthony. "Multiscale Modeling of an Industrial Nylon-6 Leacher." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/31149.
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This thesis presents a multiscale model of an industrial nylon-6 leacher. We develop several models at various spatial scales and implement them together in a simplistic, efficient way to develop an overall leacher model. We solve dynamic transport differential equations using the finite-volume method and method of lines in an in-house-developed FORTRAN program. We use the ODEPACK package of ordinary differential equation (ODE) solvers to solve our system of coupled ODEs. Our multiscale model performs transport, thermodynamic, physical property, and mass-transfer calculations at a finite-volume scale. We introduce two additional scales: a mesoscale, in which we perform computational fluid dynamic (CFD) simulations, and a molecular scale. Our CFD simulations solve for turbulent properties of fluid flowing over a packed bed. We incorporate the turbulent diffusivity of the fluid into our finite-volume leacher model. We perform molecular simulations and use the conductor-like screening model-segment activity coefficient (COSMO-SAC) model to generate solubility predictions of small, cyclic oligomers in water and ε-caprolactam. Additionally, we develop an extension of COSMO-SAC to model polymer species, which we refer to as Polymer-COSMO-SAC, and apply it to solve liquid-liquid equilibrium equations. We present a unique methodology to apply COSMO-based models to polymer species, which shows reasonable results for nylon-6. Because of the computational intensity of our Polymer-COSMO-SAC liquid-liquid equilibrium algorithm, we generate pre-computed tables of equilibrium predictions that we may import into our leacher model. Our integration of multiscale models maximizes efficiency and feasibility with accuracy.
We are able to use our multiscale models to estimate necessary parameters, but we need to fit two mass-transfer related parameters to industrial data. We validate our model against the plant data and find average-absolute errors in the final mass percent of ε-caprolactam and cyclic dimer in polymer chips of 25.0% and 54.7%, respectively. Several plant data sets are suspected outliers and we believe an unforeseen equilibrium limitation may cause this discrepancy. If we remove these outlying data sets, we then find average-absolute errors of 7.5% and 19.3% for ε-caprolactam and cyclic dimer, respectively. We then use our validated model to perform application and sensitivity studies to gain critical insight into the leacherâ s operating conditions.
Master of Science
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Kegel, Mark Steven, and n/a. "Fibres from recycled post consumer PET/nylon 6 blends." Swinburne University of Technology, 2006. http://adt.lib.swin.edu.au./public/adt-VSWT20070606.111448.
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The objective of this project was to develop blends based upon post consumer RPET and N6, and to evaluate the suitability of these blends to form fibres for the end use in carpet fibre.
In the work carried out it was found it is possible to spin RPET/N6 biconstituent fibres over a wide range of blend ratios. All the blends studied have diminished physical properties when compared to those of pure RPET and N6. The processability of these blends also deteriorated due to the large increases in normal forces which manifests in extrusion equipment as die swell that often results in melt fracture.
It has been shown that the morphology of the fibre controls the degree of decay in properties and die swell at the spinnerette. The blends that are rich in one phase, with the secondary phase distributed as elongated fibrils have shown better physical performance and improved processing compared to the blends 70/30 � 30/70, which have poorer properties and increased die swell due to there co-continuous morphology. In quiescent studies, the physical properties of the blends have had little deviation from those predicted using a rule of mixtures line. In and around the 50% RPET blend, die swell was observed to be extreme and this makes fibre spinning difficult. It was found that this was caused by a loss in viscosity in the blends and a general increase in normal forces in response to applied shear. The die swell phenomenon is a rheological characteristic of the blends, which was inevitably caused by internal capillary flow of one component in the other.
IR spectroscopy has shown that there is little to no in-situ compatibilisation occurring during simple melt processing. However, it was found that significant interfacial compatibilisation could be achieved through solid stating N6/RPET blends. The FTIR spectra for solid state blends in figure 4.51 has shown absorbency in the 3300 cm-1 region after all free N6 was removed. This indicates that in-situ compatibilisation has occurred between the phases in the solid stating process and it is a time dependent reaction.
The Burgers and Koltunov models can be used to predict the creep behaviour of the fibre blends studied. The Burgers model provides greater accuracy for longer-term exposure to stress.
From the thermal results, the solid stating process significantly affects the melting and crystallisation out of the melt and the ultimate level of crystallinity. The contribution of the copolymer in these changes appears to be small. The physical strength of the fibres made on the laboratory line was only marginally lower than those made on a factory line. The morphology of the mid-range blends is co-continuous and that of the N6 and RPET rich blends is dispersed droplet morphology.
Based on the finding, a N6 rich blends and in particular the 10% RPET blend is the most suitable for further commercial development as its processing, physical performance and post spinning processing closely resemble the pure N6 currently in use. It has provided performance and consistency throughout the processing and testing we have conducted.
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Srinivas, Srivatsan. "Crystallization behavior of nylon 6/6 and its blends with poly(vinyl pyrrolidone)." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/44859.
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This thesis presents the results of a study on the blends of an aliphatic crystallizable polyamide (nylon 6/6) and trace quantities of a polar non-crystallizable diluent (poly(vinylpyrrolidone)). This study is based on the preliminary findings of Keith et al. who reported striking morphological changes in nylon 6/6 upon addition of small amounts of poly(vinylpyrrolidone) (PVP). The melting behavior of pure nylon 6/6 was also studied during the course of this investigation.
The melting behavior of nylon 6/6 was studied using a differential scanning calorimeter (DSC). Samples were isothermally crystallized at various temperatures from the melt. Subsequent DSC analysis showed the presence of three distinct melting endotherms. The behavior of these three endotherms was studied as a function of the crystallization temperature (TC), annealing time, and DSC heating rate. X-ray studies (small and wide angle) and hot stage optical microscopy studies were also carried out to determine the cause of the multiple endotherms.
The influence of addition of PVP on the crystal morphology of nylon 6/6 was studied using DSC, x-ray and hot stage photomicroscopy. The addition of PVP has a dramatic effect on the spherulitic morphology of nylon. The addition of PVP to nylon caused a striking reduction in the nucleation density of spherulites, modification of lamellar organization in spherulites (as evidenced by the occurrence of banding), and modification of interlamellar spacings.Master of Science
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Kegel, Mark. "Fibres from recycled post consumer PET/nylon 6 blends." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070606.111448/index.html.
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Thesis (PhD) - Swinburne University of Technology, Industrial Research Institute Swinburne - 2006.A thesis submitted to Industrial Research Institute Swinburne in fulfilment of the requirements for the degree of Doctor of Philosophy, Swinburne University of Technology - 2006. Typescript. "July 2006". Includes bibliographical references (p. 147-156).
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Saman, Mansor Mohamad. "Study of the conductivity of Nylon 6/ABS blends." Thesis, Sheffield Hallam University, 1999. http://shura.shu.ac.uk/20318/.
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In this research project the study was conducted on conductivity of acrylonitrile butadiene styrene (ABS)/Nylon 6 blend with carbon black as conductive filler. Three different blends of ABS/carbon black, Nylon 6/carbon black and ABS/Nylon 6/carbon black with various compositions were prepared by mixing together by using a single screw extruder. Each compound was reblended to achieve homogeneous mixture and the effect of processing was studied. Conductivity of the low resistance of blends were obtained by measuring sheet resistance using four-point probe as according to ASTM F 1529. The sheet resistance could only be detected for ABS/carbon black 20 wt % and above, and ABS/Nylon 6 with 80:20 ratio with 10 wt % of carbon black. Whereas, for Nylon 6/carbon black blends and the others high resistance of blends, their resistances were measured by Teraohmeter according to ASTM D 257 method. Percolation threshold (critical volume fraction) of the blends was studied to find actual conductive filler contents to avoid deterioration of mechanical properties. In this case, tensile tests were conducted according to ASTM D 638 to establish their mechanical properties. Meanwhile, scanning electron microscopy (SEM) was used to study the morphology of blended polymers, interface of polymer/carbon black and aggregation phenomenon between carbon black and polymers. The correlation between conductivity, mechanical properties and morphological characterisation of all the blends was studied. The results show that, the addition of carbon black up to 10%, increases conductivity and tensile strength of ABS/carbon black and Nylon 6/carbon black blends. Conductivity continues to increase with further addition of carbon black, but at the expense of tensile strength reduction due to the effect of brittle nature of carbon black. By adding ABS in ABS/Nylon 6/carbon black blends, conductivity increases, whereas tensile strength decreases. However, tensile strength of ABS/Nylon 6/carbon black blends were too low to compare with individual polymer blended with carbon black, due to immiscibility between ABS and Nylon 6. Reblending the compound for the third time increases conductivity and mechanical properties due to increase in homogeneity and uniform distribution of carbon black dispersion. Both ABS and conductive carbon black absorb moisture that can effect the properties of compound. Drying of the compound will remove moisture which will result in improvements in conductivity and tensile strength.
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Allafi, Ahmad Rashid. "Effect of Different Percent Loadings of Nanoparticles and Food Processing Conditions on the Properties of Nylon 6 Films." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1211909852.
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Wang, Lei Materials Science & Engineering Faculty of Science UNSW. "Molecular dynamics simulation of ODTMA-Montmorillonite and nylon 6 nanocomposites." Awarded by:University of New South Wales. School of Materials Science and Engineering, 2007. http://handle.unsw.edu.au/1959.4/28065.
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Polymer materials stand on a very significant position in the materials industry area. The presence of organoclay nanocomposites reinforces polymer materials on many properties like strength, tensile and so on. Most previous studies on the characteristics of organoclays and polymer nanocomposites were based on the experimental approaches such as XRD (X-ray Diffraction) and NMR (Nuclear Magnetic Resonance). These methods have achieved successfully on the basic analysis of chains and layering structures of polymer nanocomposites. However, information on the molecular level cannot be provided by those approaches. MD (Molecular Dynamic) simulation method could be employed to develop further information on the molecular level about organoclays and interlayer structure polymer nanocomposites. In the research of ODTMA-MMT (Octadecyltrimethylammonium-Montmorillonite) organoclay simulation, we find that the strong layering behaviour of interlayer ODTMA molecules is present with the same minimum distance between nitrogen atoms and MMT surface in different T/O (Tetrahedral vs. Octahedral) ratio cases. Nitrogen atoms sit right above the corresponding hexagonal cavities, which is in agreement with the previous research. The interaction energy between surfactants and MMT clay will reach the lowest point when substitution ratio of tetrahedral and octahedral (T/O) is equal to 1:1. Moreover, MSD (Mean Square Displacement) and diffusion coefficient of different models under same CEC (Charge Exchange Capacity) condition are inverse ratio to the T/O proportion. In nylon6 polymer nanocomposites, sodium cations which exist originally in ensemble as charge balancer are absorbed much closer to MMT surface than the organic components in the nylon 6 ODTMA-MMT ensemble. Sodium atoms or nitrogen atoms in surfactants both have higher MSD and coefficients than those atoms in the organic-modified clays. In the exfoliated nylon 6 ODTMA-MMT nanocomposites, pair correlation has been analysed instead of density profile. Layering packing structure is also shown through this analysis, which is also consistent with previous work.
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Deshpande, Anushree. "Synthesis and Characterization of in-situ Nylon-6/Epoxy Blends." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1480328231030708.
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Schreiber, Rainer. "Untersuchung der Einflüsse von Spinngeschwindigkeit und Streckgrad auf Struktur und Orientierung von Nylon-6 Fasern mit Hilfe der Festkörper-NMR-Spektroskopie." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960848630.
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Oliveira, Herbert Pereira de 1972. "Unidade experimental de polimerização para desenvolvimento de nylon-6 para novas aplicações." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266103.
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Orientador: Rubens Maciel FilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Este trabalho teve como objetivo principal a proposta de projeto de uma planta piloto de polimerização Nylon 6 para o desenvolvimento de novas aplicações. O processo adotado é a polimerização hidrolítica do Nylon 6, a partir do monômero ?-caprolactama, que compreende a vaporização de ambos, monômero e água, em um reator de bancada operado no regime de batelada. O Nylon 6 vem sendo produzido no Brasil quase que exclusivamente para emprego no setor de fibras, mas outras aplicações aumentariam o consumo deste polímero. Assim, o desenvolvimento de Nylon 6 para outros fins, como por exemplo no setor de plásticos de engenharia (eletrodomésticos e setor automotivo) é necessário para diversificar o seu consumo, direcionando-o a novos mercados, como forma de garantir a sua permanência e utilização neste setor altamente competitivo, que é o setor de plásticos como um todo, no qual, em face da globalização, os diversos produtos passam a competir nos mais diversos campos de aplicação. Este trabalho compreendeu o projeto conceitual, detalhamento de projeto, desenvolvimento, construção, montagem e definição de procedimentos experimentais da planta piloto, de modo a reproduzir, em escala piloto, as condições do processo industrial de polimerização em batelada. Concluída a etapa de projeto, construção e montagem, e comissionamento da planta, foram realizados testes pré-operacionais, com análise e correção dos problemas verificados. Foram realizadas duas corridas experimentais e as amostras do polímero obtido foram caracterizadas e comparadas às amostras padrões fornecidas por indústrias locais. A planta desenvolvida se mostrou operacional e flexível para o desenvolvimento de Nylon 6 com características controladas, o que é necessário para as possíveis aplicações como plástico de engenharia
Abstract: This investigation aimed to propose the design of a Nylon 6 pilot plant polymerization for the development of new applications. The process adopted is the hydrolytic polymerization of nylon 6 from epsilon-caprolactam monomer comprising vaporization of both, monomer and water, in a batch operated reactor. The Nylon 6 has been produced in Brazil almost exclusively for fiber sector employment, and new applications are welcome to increase the production of such polymer. Thus, the development of Nylon 6 for other purposes, such as in engineering plastics sector (appliances and automotive) is necessary to diversify their consumption, directing you to new markets as a way to ensure its permanence and use this highly competitive industry, which is the plastics industry as a whole, which, in the face of globalization, the products are competing in various application fields. This research work comprised the proposal of a conceptual design, detailed design, development, construction, installation and definition of experimental procedures of a pilot plant, for Nylon 6 polymerization, in order to be able to reproduce in a pilot plant scale, industrial process conditions in batch polymerization. After the design phase, construction, assembly, and plant commissioning, pre-operational tests were performed, with analysis of the results and correction of detected problems. Two experimental runs were performed and samples of the polymer obtained were characterized and compared with standard samples supplied by local industries. The pilot plant proved to be and operational with a good degree of flexibility to the development of Nylon 6 with controlled characteristics, which is necessary for the potential applications as engineering plastics
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
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Miraftab, M. "The influence of temperature and humidity on the flex fatigue lives of nylon 6, nylon 6.6 and polyester fibres." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375735.
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A multi-station flex fatigue tester has been developed, allowing a wide range of environmental settings. A detailed study of fatigue behaviour under increasing temperature and humidity is made. In general, an upward trend in fatigue life of all the polymers tested is recorded with increasing temperature and humidity. Scanning electron microscope studies of unbroken samples under specific conditions revealed a central split in the fibre at the point of flexure. Partially fatigued fibres are tensile tested for their remaining strength and their fracture morphologies examined. Finally, a theoretical explanation of the apparent cause of increase in fatigue life is given in relation to the development of the central crack.
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Hashim, Kamaruddin. "Compatibilization of poly(vinylidene fluoride)/nylon 6 blends by intermolecular association." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/25382.
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Blends of poly(vinylidene fluoride) (PVDF) and polyamide 6 (N6) are interesting for both scientific studies and commercial exploitation. PVDF is known to be miscible with polymers produced from monomers containing carbonyl side groups, eg. polyethyl acrylate, polyacrylamide etc., but is not miscible with polymers containing carbonyl groups in the main chain, ego polyamides, polyester, etc. Although complete miscibility of the blend components is not always necessary, strong physical interactions between the two components are needed in order to obtain a compatible blend, i.e. one which exhibits good mechanical properties. An investigation was carried out to explore the possibility to compatibilise blends of PVDF and N6 using y-radiation to graft acid groups on either polymer and subsequently ionomerizing these with zinc cations. Graft copolymer type of compatibilizer was produced when the acid functionalized PVDF (grafted PVDF) was blended with N6 or acid functionalized N6 (grafted N6). Fourier transform infrared analysis has confirmed the occurance of reactions between acid groups in the grafted PVDFand amine groups in the N6. The compatibility of the PVDF/N6 blends was found to increase with increasing amount of carboxylic acid groups in the two polymers. This was accompanied by an increase in Tg of the N6 phase in blend, which became more pronounced when both components were grafted. Tensile test and solvent resistance experiments were carried out to relate the compatibization of the blend to the improvement in mechanical properties. Ionomerization of the functionalized polymers with zinc cations was performed in order to study the effect on compatibility of the blend. The neutralization of the acid groups in either polymer in the blend by addition of zinc acetyl acetonate was found to suppress the chemical reaction with the amine end groups in the N6 phase, and to cause a reduction in the T g and a reduction in crosslinking of the N 6 phase. However when both polymers were grafted, the crystallinity of the N6 phase was restored, which was accompanied by an increase in Tg.
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Tedesco, Adriana. "Polipropileno graftizado com metacrilato glicidila como agente compatibilizante em blendas de PP e nylon 6." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2001. http://hdl.handle.net/10183/3231.
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Neste trabalho foi feito uma avaliação do polipropileno funcionalizado com metacrilato de glicidila (PP-GMA) como agente compatibilizante em blendas reativas de polipropileno e nylon 6. As reações de funcionalização do polipropileno (PP) com metacrilato de glicidila (GMA) foram feitas em estado fundido e os polímeros modificados (PP-GMA) foram utilizados em misturas de PP com nylon 6, para a avaliação das propriedades mecânicas, térmicas e morfológicas da blenda. As blendas foram preparadas variando a concentração de nylon 6 e também do agente compatibilizante. Após o estudo da ação da concentração de nylon 6 e do agente compatibilizante nas blendas, foi verificado o comportamento do PP-GMA com diferentes teores de incorporação molar do GMA no polipropileno. Utilizou-se dois tipos de nylon 6, um deles com maior número de terminais carboxílicos, a fim de avaliar o efeito desses grupos na compatibilidade do sistema. As blendas obtidas foram caracterizadas por calorimetria diferencial de varredura, microscopia eletrônica de varredura e análise das propriedades mecânicas e dinâmico-mecânicas. Os resultados mostraram que a adição do PP-GMA provoca alterações na morfologia das blendas, apresentando uma melhor dispersão e redução no tamanho das partículas dispersas. Além disso, há um aumento nas propriedades mecânicas comparado com as propriedades das blendas não compatibilizadas, que pode ser atribuído a melhor adesão entre as fases para ambos os nylons utilizados neste trabalho. Foi feito estudo comparativo entre as blendas de PP/PP-GMA/Ny6 e PP/PP-MA/Ny6 na proporção de 63/7/30. O efeito do tipo de agente compatibilizante foi caracterizado por calorimetria diferencial de varredura, microscopia eletrônica de varredura e análise das propriedades mecânicas e dinâmico-mecânicas. Os resultados indicaram que o polipropileno modificado com anidrido maleico (PP-MA) mostrou um melhor efeito compatibilizante nesses sistemas. Ou seja, a interação dos terminais amino do nylon foram mais suscetíveis a ação do grupamento anidrido no PP-MA, do que o grupamento epóxido no PP-GMA.
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Averett, Rodney Dewayne. "Fracture Mechanics of High Performance Nylon Fibers." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5238.
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A fracture mechanics protocol appropriate for small fibers (35 micron diameter) is presented, which allows for the determination of the strength limitations of high performance nylon 6,6 fibers. Specifically, linear elastic fracture mechanics (LEFM) techniques are employed in addition to elastic-plastic fracture mechanics (EPFM) theories to achieve this.
We assume that a minute semi-elliptical flaw of an unknown size exists in the specimen, as a result of the detrimental effects of the manufacturing process (melt spinning). Next, we seek to propagate this flaw in a stable manner through an ancillary process such as high cycle or low cycle fatigue (load-unload). After propagation, uniaxial tensile experiments are performed on the fatigued samples, by which the crack growth eventually becomes catastrophic during the process. After performing scanning electron microscopy (SEM) techniques and reviewing fractography, we are able to determine the critical flaw size and ligament length that leads to unstable crack propagation. These results are substituted into the appropriate LEFM equations and are in close agreement with material properties for nylon 6,6. A discussion is provided that draws parallel to the topics discussed in the literature investigation and the experimental results of this study.
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Zhou, Xiaojuan. "Selective hydrogenation of lignin-derived model compounds to produce nylon 6 precursors." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52917.
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This study investigated the conversion of monomeric lignin fragments into cyclohexanols for use as a source of lignin-derived monomers for renewable Nylon 6 production. Lignin-derived
monomeric phenolic species was transformed to their cyclohexanol analogs via selective catalytic hydrogenation. A fixed-bed flow reactor was used to evaluate the selective hydrogenation of individual model phenolic species (guaiacol, 4-methylguaiacol or diphenyl ether). The catalyst composition studied was Ni/SiO₂, which was previously shown to form cyclohexanol as an intermediate from phenol. A primary focus was on tuning the reaction conditions to form desired products, while avoiding the formation of bicyclic species which can be precursors
to catalyst deactivation, or fully hydrogenated products of lower value. Reaction pathways of guaiacol, 4-methylguaiacol and diphenyl ether were studied. Major products obtained from guaiacol, 4-methylguaiacol and diphenyl ether reactions were 2-methoxycyclohexanone, 4-methylcyclohexanol and cyclohexanol, respectively. Spent catalyst was analyzed for extent of deactivation.
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Veith, Cary Alan. "New siloxane - nylon-6 diblock copolymers for emulsification and toughening of blends." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14336.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1989.Title as it appeared in MIT Graduate list, June, 1989: Siloxane-nylon-6 diblock copolymers for emulsification and toughening of blends.
Includes bibliographical references.
Cary Alan Veith.
Ph.D.
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Vyas, Aniket. "Morphology and Properties of Clay/Nylon-6-Epoxy Nanocomposities Coatings and Films." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1414750283.
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Czarnecka, Anna. "Preparation and Characterization of Kaolinite-based Nanocomposite Materials." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24379.
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A kaolinite-nylon 6 composite was prepared by a polycondensation reaction from 6-aminohexanoic acid (AHA) intercalated in the kaolinite interlayer space. The basal spacing of kaolinite-AHA was 1.47 nm and the basal spacing of the heated products decreased to 1.16 nm. The signals attributed to nylon 6 were detected in the 13C CP/MAS NMR spectra of the heated products. Formation of nylon 6 in kaolinite was confirmed by appearance of IR band due to amide I and amide II.
Sarcosine was intercalated in kaolinite for the first time by guest displacement with methanol from the kaolinite-methanol precursor. The basal spacing of kaolinite-sarcosine was 1.27 nm. This intercalation compound was characterized by NMR, TGA, XRD, and IR.
The physical and chemical properties of natural clay sample from Mirandela formation (Portugal) were determined in terms of external skin treatment. The low CEC 4,45meq/100g is consistent with high content of kaolinite in the sample
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Rezende, Camila Alves de 1980. "Blendas de nylon-6 com polietileno e polipropileno para fabricação de fibras texteis." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249547.
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Orientadores: Ulf Friedrich Schuchardt, Maria do Carmo GonçalvesDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
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Seavey, Kevin Christopher. "Research and Development of Simulation and Optimization Technology for Commercial Nylon-6 Manufacturing Processes." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26930.
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This dissertation concerns the development of simulation and optimization technology for
industrial, hydrolytic nylon-6 polymerizations. The significance of this work is that it is a
comprehensive and fundamental analysis of nearly all of the pertinent aspects of
simulation. It steps through all of the major steps for developing process models,
including simulation of the reaction kinetics, phase equilibrium, physical properties, and
mass-transfer- limited devolatization. Using this work, we can build accurate models for
all major processing equipment involved in nylon-6 production.
Contributions in this dissertation are of two types. Type one concerns the formalization
of existing knowledge of nylon-6 polymerization mixtures, mainly for documentation and
teaching purposes. Type two, on the other hand, concerns original research contributions.
Formalizations of existing knowledge include reaction kinetics and physical properties.
Original research contributions include models for phase equilibrium, diffusivities of
water and caprolactam, and devolatization in vacuum- finishing reactors.
We have designed all of the models herein to be fundamental, yet accessible to the
practicing engineer. All of the analysis was done using commercial software packages
offered by Aspen Technology, Cambridge, MA. We chose these packages for two
reasons: (1) These packages enable one to quickly build fundamental steady-state and
dynamic models of polymer trains; and (2) These packages are the only ones
commercially available for simulating polymer trains.Ph. D.
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Fasahat, F., R. Dastjerdi, and M. R. M. Dastjerdi. "Abrasion Resistance of Ag/SiO2/PA6 Nanocomposite Fabrics." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35638.
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In recent decades, polymeric nanocomposites have been widely used in chemical, automobile and aero industries due to their low weight and smoothness. Abrasion resistance is a vital property in variable ap-plications of polymeric composites. Here, to investigate the wear resistance of nylon 6 nanocomposite fab-rics, melt spun yarns were filled with different concentrations of Ag/SiO2 nanoparticles and the wear prop-erties of weft knitted nanocomposite and pure samples were evaluated. Results disclosed that the wear re-sistance of composite fabrics containing nano-particles increased considerably in comparison to pure one. Therefore, nanoparticles can play an important role in improving the nanocomposite wear resistance.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35638
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Liu, Zhihui. "Properties of 3D Printed Continuous Fiber-Reinforced CNTs and Graphene Filled Nylon 6 Nanocomposites." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1512045511745974.
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Pinheiro, Luís Antonio. "Monitoramento em tempo real da morfologia na extrusão da blenda polimérica polipropileno/ nylon 6." Universidade Federal de São Carlos, 2006. https://repositorio.ufscar.br/handle/ufscar/648.
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Previous issue date: 2006-09-01Universidade Federal de Sao Carlos
The aim of this work is to assess in real time the morphological parameters of polypropylene and polyamide 6 blends during the extrusion process. An optical detector based on the visible light transmitted and extinction principle was assembled in a slit die located at the exit of a twin screw extruder in order to get the changes in the polyamide 6 particle concentration and size. The influence of particle size and concentration was first verified during bench calibration, where it was observed that the light extinction was greater the higher the concentration and the lower the particle size. In the case of mixtures an additional relation concerned to changes in size and density was verified. It was also stated that the detector records the ponderal average size of a set of particles. During extrusion experiments, the analyses were performed in the steady and transient state. In both cases it was verified that normalized signal intensity increases with increasing particle concentration and decreasing the dispersed phase size. Infrared analysis and images obtained from scanning electron microscopy confirmed these results. The correlation between dispersed phase concentration and size with the detector s normalized signal was established through the elaboration of regression equations. The plot of normalized signal as a function of the dispersed phase concentration and size enabled the calculation of the extinction cross section values for the PP/ PA6 blend.
Neste trabalho se buscou avaliar parâmetros morfológicos de blendas de polipropileno e poliamida 6 em tempo real durante o processo de extrusão. Um detector ótico, baseado no princípio da extinção da luz visível transmitida, foi acoplado na matriz da extrusora para captação do sinal referente a variações na concentração e tamanho de fase de poliamida 6. A influência da concentração e tamanho de partícula foi primeiramente determinada por calibrações em bancada, onde se verificou que a extinção da radiação luminosa era maior tanto maior a concentração e menor o tamanho de partícula. No caso de misturas de partículas verificou-se uma relação de aditividade quanto à variação de tamanho e densidade, e constatou-se que o detector registra o valor referente ao tamanho médio ponderal das partículas. As análises durante o processo de extrusão foram feitas em modo transiente e estacionário. Em ambos os modos foi verificado que a intensidade do sinal normalizado aumenta com o aumento na concentração e com a diminuição do tamanho da fase de poliamida 6 dispersa. Análises de espectroscopia no infravermelho e de imagens obtidas por microscopia eletrônica de varredura confirmaram os resultados obtidos pelo detector. A correlação entre concentração e tamanho de fase dispersa foi estabelecida através da elaboração de equações de regressão. Os gráficos do sinal normalizado em função da concentração e do tamanho de fase possibilitaram o cálculo da seção transversal de extinção, variável relacionada com a probabilidade de interação da radiação com as partículas espalhadoras do meio.
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Bomfim, Marcus Vinicius Justo. "Avaliação sanitária de filmes de poliamida (nylon 6) em embalagens acondicionantes e alimentos gordurosos." reponame:Repositório Institucional da FIOCRUZ, 2008. https://www.arca.fiocruz.br/handle/icict/9251.
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Fundação Oswaldo Cruz. Instituto Nacional de Controle de Qualidade em Saúde
A embalagem é definida como o artigo que está em contato direto com os alimentos, destinado a contê-los desde a sua fabricação até sua entrega ao consumidor, com a finalidade de protegê-los de agentes externos, alterações e de contaminações, assim como adulterações. Entretanto a própria embalagem pode representar fonte de risco através da migração de substâncias de sua própria constituição para o alimento, principalmente, aqueles gordurosos. A e-caprolactama (CAP) é um monômero precursor de polímeros denominados nylon 6 para embalagens de alimentos como mortadelas, blanquet de peru, peito de aves, patês e apresuntados. O objetivo do projeto foi avaliar a migração de resíduos de CAP presentes em embalagens de poliamida e utilizadas, em geral, no acondicionamento de alimentos gordurosos. A determinação da CAP foi realizada através de ensaio de migração preconizado pela Diretiva européia n° 711, de 18 de outubro de 1982, no qual a embalagem permanece em contato com o etanol 95 por cento, meio que simula as características de um alimento gorduroso. A CAP foi identificada e quantificada através de cromatografia a gás com detecção por ionização em chama. O método foi validado intralaboratorialmente e considerado adequado ao propósito. Dentre as embalagens analisadas, 35 por cento das embalagens para mortadela suína, de frango ou chester; 33 por cento para blanquet de peru e 100 por cento para peito de aves e patês apresentaram migração superior ao limite estabelecido pelas legislações brasileira e européia. Caso o etanol 95 por cento fosse aceito como simulante D alternativo pela legislação brasileira (BRASIL,1999) como é pela legislação européia (CE,1982), tais amostras seriam consideradas não conformes por ambas as legislações (BRASIL,1999; UE,2002). Somente os valores de migração específica de embalagens sem identificação e rótulos (ND) e de apresuntado não ultrapassaram o limite de migração específica de 15mg/kg.
Packaging is an article in direct contact with foods from manufacture up to delivery to the consumer, which provides protection against external agents, alterations, adulterations and contamination. However, packaging itself can represent risk through the migration of substances in its own constitution into the food, especially fatty foods. ε-Caprolactam (CAP) is a precursor monomer of nylon 6 used as food packaging for bologna sausage, turkey blanquette, fowl breast, patés and ham luncheon meat. Our objective was to evaluate the migration of CAP residues in nylon 6 packagings used generally for fatty foods. CAP evaluation was based on migration assays established by European Directive n° 711, of 18 October 1982, in which packaging material remained in contact with ethanol 95%, simulating fatty food characteristics. CAP was identified and quantified by a gas chromatograph equipped with a flame ionization detector. The method was in-house or single-laboratory validated and considered adequate for this purpose. Packaging analysis showed migration at levels higher than the limits established by Brazilian and European Union laws (15 mg/kg of food) for 35% of bologna sausage, 33% of turkey blanquette and 100% of fowl breast and paté packagings. These materials would be considered in contravention of Brazilian laws as they are of European laws, if ethanol 95% was accepted as alternative simulant D by Brazilian legislation. Only ham luncheon meat and packaging without labels did not exceed specific migration limit. Epidemiological studies indicate that CAP could cause ocular, cutaneous and respiratory irritations, as well as hypotension, palpitations, rhinorrhea, nasal dryness, neurological and blood problems and genitourinary and reproductive effects, such as alterations in ovarian-menstrual functions and pregnancy/birth complications. The majority of in vitro and in vivo genotoxicity studies by oral and intraperitoneal routes show negative results, including the absence of carcinogenicity in rats and mice or developmental and reproductive effects in rats and rabbits.
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Hutchins, Deborah Ann. "Activity, Stability, and Binding Capacity of β-Galactosidase Immobilized on Electrospun Nylon-6 Fiber Membrane." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/9173.
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This research explores various immobilized enzyme support materials, including the novel nylon-6 fiber membrane (NFM), observing the increase of surface area and what effect that has on enzyme binding potential. This study also manipulates incubation and reaction conditions and observes what affect that has on activity and stability of β-galactosidase comparing various solid support materials and free enzyme. Nylon-6 fiber membranes were created using the process of electrospinning and were compared with other materials as solid support materials for enzyme binding. The other materials included polyvinylidene fluoride 5 kD nanofiltration dairy membranes, nylon-6 pellets, silica glass beads, and free—dissolved—enzyme. Scanning electron microscopy images exposed the nylon-6 fiber membrane’s large amount of surface area which coordinated with greater enzyme activity as compared to the relatively flatter surfaces of the other solid support materials. Enzyme activity was measured spectrophotometrically with the color-changing substrate ortho-Nitrophenyl-β-galactoside. NFM had greater maximum enzyme binding potential than the other solid supports. Across pH conditions ranging from 3.5 to 6.0., enzyme activity was maintained on the membrane immobilized samples whereas free enzyme did not maintain activity. Altering storage temperature (4, 22, and 50 °C) affected enzyme stability, the ability of the enzyme to maintain activity over time, of free and polyvinylidene fluoride membrane samples. However, nylon-6 fiber membrane samples maintained stability across the varying storage temperatures. Increasing the immobilization solution enzyme concentration above maximum enzyme binding capacity had no significant effect on enzyme stability for membrane immobilized samples. Although, both had lower mean stability than free enzyme by approximately 74% percent. With further development, β-galactosidase immobilized on nylon-6 fiber membranes, or other membranes, could be used in continuous processing in the dairy industry for a combination of filtration and lactose hydrolysis—creating products reduced in lactose and increased in sweetness with no “added sugars” requirement for a nutrition label and no enzyme listed as final product ingredient.
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Oliveira, Marcelo Ferreira Leão de. "Tenacificação em Nanocompósitos de Poliamida 6 e Argila." Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2830.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorNanocompósitos de poliamida 6 (PA6) e montmorilonita modificada com sal de amônio quaternário têm sido estudados, visando melhorar as propriedades térmicas e mecânicas. De fato os efeitos da nano-escala e da interação carga-matriz resultam em maior módulo de elasticidade e resistência à tração, porém a deformação é reduzida. Assim, nesse trabalho, optou-se por adicionar elastômeros, terpolímero de etileno-propileno-dieno (EPDM) e terpolímero de etileno-propileno-dieno modificado com anidrido maleico (EPDM-MA), ao sistema PA 6/argila organofílica para recuperar os valores de deformação. Foi utilizada montmorilonita modificada com cloreto de dimetildioctadecil amônio. A intercalação por fusão foi realizada em câmara interna de mistura. Além das propriedades mecânicas, térmicas e reológicas, foram investigadas as modificações na cristalinidade da fase PA-6 em função da adição da argila modificada, EPDM e EPDM-MA, detectando-se as variações no grau de cristalinidade e nas temperaturas de fusão e cristalização. Os difratogramas de raios-x revelaram ocorrência de intercalação/esfoliação e também modificação da forma cristalina da PA 6, indicando a formação do cristal gama
Nanocomposites of polyamide 6 and montmorillonite modified with alquil-ammonium salts have been studied, searching for the improvement of mechanical and thermal properties. In fact the effects of the nano-scale and the interaction matrix-filler result in larger module of elasticity and tensile strength. However, the elongation at break was greatly reduced. Therefore, in this work, it has been decided to add elastomers, ethylene-proplene-diene terpolymer (EPDM) and ethylene-proplene-diene terpolymer funcionalized with maleic anhydride (EPDM-MA), to the system PA6/organoclay, using modified montmorillonite with ditallowdimethylammonium chloride. The nanocomposites were prepared by melt intercalation technique in a mix internal chamber. Besides the mechanical, thermal and rheological properties, the modifications in the crystallinity of PA6 phase were investigated, being detected the variations in the degree of crystallinity and in the melt temperature and crystallization. The diffractograms of x-ray (XRD) revealed occurrence of intercalation/exfoliation as well as modification of the crystalline form of PA 6, indicating the formation of crystals
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Najem, Johnny Fares. "Study of Take-Up Velocity in Enhancing Tensile Properties of Aligned Electrospun Nylon 6 Fibers." University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1258556944.
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Costa, Maria Carolina Burgos. "Desenvolvimento de nylon-6 em unidade experimental de polimerização para aplicação em prototipagem rapida com laser de CO2." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267132.
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Orientadores: Rubens Maciel Filho, Andre Luiz JardiniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Uma característica importante no projeto de uma unidade experimental de polimerização é o fato de que, já nas primeiras etapas de síntese conceitual do processo, sejam considerados os aspectos econômicos associados ao mesmo. O potencial econômico do processo deve ser analisado para descartar alternativas inviáveis e para ordenar, segundo seu potencial de rentabilidade, as que devem seguir sendo objeto de estudo e desenvolvido em etapas posteriores. Este trabalho tem como objetivo o projeto e a implantação de uma unidade experimental de polimerização, destinada ao desenvolvimento de Nylon-6 para novas aplicações como plástico de engenharia, em especial para aplicações em processo de prototipagem rápida com laser de CO2. O processo investigado é a polimerização hidrolítica do Nylon-6, a partir do monômero e-caprolactama, em um reator de bancada em batelada. Foram identificadas as condições operacionais para obter o polímero com as propriedades desejadas, levando-se em conta as várias etapas da reação. Os estudos de modelagem e simulação do processo incluem os passos necessários para o desenvolvimento do modelo, envolvendo as equações da cinética de reação de polimerização e os balanços de massa e energia. O modelo desenvolvido é útil para otimizar o desempenho do reator experimental e, consequentemente, investigar várias alternativas operacionais, visando encontrar soluções mais econômicas para o processo. O polímero obtido a partir da planta piloto de polimerização poderá ser empregado como insumo em processos de prototipagem e em particular na máquina de prototipagem rápida, desenvolvida e instalada no Laboratório de Otimização, Projeto e Controle Avançado (LOPCA), possibilitando o desenvolvimento de protótipos e modelos tridimensionais, além de produtos com alto valor agregado.
Abstract: A main characteristic in the design of polymerization experimental unit is to take into consideration economic aspects already in initials stages of conceptual synthesis of the process. The economic potential of the process has to be analyzed in order to take decisions about possible alternatives so that it is possible to classify by its potential performance the options which should remain for further studies in advanced stages of process conceptual design. This research has as main objective the design, implementation and operation of an experimental polymerization unit for development of Nylon-6 especially focused for new applications as a engineer plastic - in special on its application on processes of rapid prototyping using CO2 laser. Specifically, the examined process is the hydrolytic polymerization of Nylon-6 (from e-caprolactam monomer) in a batch reactor. A search was carried out to define the process operational conditions taking into account all the reaction steps. The efforts on process modeling and simulation include the necessary paths to the model development, involving kinetic equations of polymerization reaction and the mass and energy balances. The developed model is useful to optimize the experimental reactor performance and, then, investigate several possible operational alternatives, bearing in mind the objective of establish better economic solutions for the process, whereas keeping the desired properties.
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
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Bryson, Latoya G. "Monomer recovery from nylon carpets via reactive extrusion." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22618.
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Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2008.Committee Chair: Muzzy, John D.; Committee Member: Cook, Fred L.; Committee Member: Jones, Christopher W.; Committee Member: Mayor, J. Rhett; Committee Member: Realff, Matthew J.; Committee Member: Schork, F. Joseph.
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McAdam, Craig Peter. "Characterisation of nylon 6/clay and PMMA/clay nanocomposites prepared by ultrasonication and in situ polymerisation." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438142.
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Funai, Vanessa Ito. "Equacionamento e simulação do processo de polimerização hidrolítica de nylon-6 em um reator semi-batelada." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266871.
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Orientador: Rubens Maciel FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Este trabalho apresenta o equacionamento e simulação do processo de polimerização hidrolítica de nylon-6 em um processo semi-batelada a partir do monômero ?-caprolactama e utilizando um terminador de cadeia ácido monofuncional, no caso, o ácido acético. O modelo cinético considerado levou em conta 6 reações, sendo 3 principais, duas reações secundárias que consideram a formação de dímero cíclico no processo e uma de terminação de cadeia. Foram desenvolvidas equações de taxas de reação globais e por componente, balanço de massa das fases líquida e vapor, balanço de energia para o reator e para a jaqueta de resfriamento, transferência de massa e equilíbrio químico. A modelagem matemática levou em conta as duas abordagens mais freqüentemente encontradas na literatura para a polimerização do nylon-6: uma utiliza o método dos momentos para representação da distribuição de peso molecular, enquanto a outra considera as moléculas de polímero como múltiplos grupos funcionais, sendo a modelagem em função desses grupos. Optou-se pelo modelo de contribuição de grupos para a simulação, realizada no simulador de processos Aspen Polymer Plus® e validada a partir de dados experimentais. Por meio de simulação e planejamento experimental, investigou-se a influência da proporção de reagentes na alimentação e das condições operacionais (perfis de pressão e temperatura) com relação à conversão e massa molar média numérica. Essa avaliação é de grande interesse, uma vez que tais condições são necessárias para realizar as diversas etapas da polimerização e possuem significante impacto nas características do produto e, portanto, em suas aplicações. Também foram analisados perfis dinâmicos de diversas variáveis do processo, tais como composição do reator e da saída de vapor, massa molar média, grau de polimerização médio. As simulações a partir do modelo matemático validado mostraram-se importantes por permitir realizar com maior agilidade estudos relacionados ao processo, uma vez que experimentos na planta são demorados e dispendiosos. Os resultados permitiram uma melhor compreensão do processo, o qual é considerado complexo, e podem ser aplicados na otimização do desempenho do reator experimental
Abstract: This work presents the equating and the simulation of the hydrolytic polymerization process of nylon-6 in a lab-scale semi-batch reactor, using ?-caprolactam as monomer and acetic acid as monofunctional acid chain terminator. The kinetic scheme comprises 6 reactions: 3 main reactions, 2 side reactions associated with the cyclic dimer formation and one monofunctional acid termination. Equations for global reaction rates, reaction rates for species, mass balance for liquid and gas phases, energy balance for the reactor and the cooling system, mass transfer model and phase equilibrium model were developed. The mathematical model took into account the two approaches most frequently found in the literature for the nylon-6polymerization. The former uses the method of moments to represent the molecular weight distribution, while the latter considers the polymer molecules as multiple functional groups and the modeling is expressed in terms of these groups. The approach by group contribution was chosen for implementation in Aspen Polymer Plus® process simulator and the validation was performed with experimental data. The influence of the of the effects of the process variables and feed conditions on the e- caprolactam conversion (XCL) and nylon-6 number average molecular weight (MWN) were investigated by using of simulation and experimental design. This evaluation is quite interesting since such profiles are necessary to carry out the several polymerization steps and have a significant impact on product characteristics and therefore in its applications. Have also been studied the dynamic profiles of some process variables, like reactor and vapor composition, average molecular weight and polymerization degree. Since experimental runs are time consuming and expensive, simulations from the validated model showed to be very important, for allowing studies with more agility. The results allowed a better comprehension of the process, which is considered complex, and can be applied for optimization of the performance of the experimental reactor
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
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Medeiros, Marco Antônio Rocha. "Propriedades mecânicas de compósitos de PVC reciclado reforçados com fibras de sisal e de nylon 6." reponame:Repositório Institucional da UFBA, 2006. http://www.repositorio.ufba.br/ri/handle/ri/9720.
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A pesquisa aqui apresentada teve como objetivo principal avaliar as propriedades mecânicas (resistência à tração, impacto e dureza) de compósitos produzidos com materiais residuais da indústria, constituídos por fase matriz de PVC reciclado e fase dispersa com frações volumétricas de 5, 10 e 20 % tanto de fibras de nylon 6 quanto de fibras de sisal. Objetivou, também, determinar em que medida o reforço de fibras curtas e orientadas aleatoriamente, poderia recuperar no PVC reciclado, as propriedades originais do PVC. Isto porque, sabe-se que os polímeros termoplásticos quando submetidos a processos de reciclagem tendem a apresentar perda nos valores de propriedades mecânicas, em virtude de rompimento de ligações entre suas cadeias moleculares. A pesquisa, ao usar materiais, resíduos e rejeitos industriais, notadamente o PVC e o sisal, visando futuro aproveitamento em novos materiais de construção, contribui não só para minimizar o impacto negativo do descarte de tais materiais nos resíduos sólidos urbanos, mas, também, para a busca do desenvolvimento sustentável. Apresenta revisão bibliográfica sobre pesquisas realizadas com compósitos similares além dos métodos seguidos para a produção e caracterização física e química dos compósitos, produzidos através de moldagem por injeção, e os procedimentos para realização dos ensaios mecânicos de tração direta, de impacto e de dureza. O PVC reciclado utilizado foi resultante de moagem e posterior pulverização de conexões produzidas com a mesma matéria prima utilizada para o PVC original As fibras de sisal, com comprimento médio de 3,5 cm, foram utilizadas nos compósitos, sem nenhum prévio tratamento térmico ou químico. As fibras de nylon, com comprimento médio de 2,5 cm, sendo rejeitos industriais, já possuíam um revestimento com um composto à base de látex, formaldeido e resorcinol. Os principais resultados da pesquisa foram: (i) o PVC reciclado teve desempenho mecânico semelhante ao do PVC original, em virtude de não ter passado por processo de envelhecimento acelerado, ou seja, praticamente manteve a mesma estrutura molecular do PVC original; (ii) entre as fibras, o sisal apresentou melhor desempenho que o nylon em todas as situações estudadas, pois além do seu módulo de elasticidade ser bastante superior que o do nylon 6, demonstrou ter havido, nas suas formulações, melhores coeficiente de forma e aderência na interface matriz-fibra.
Salvador
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劉麗君. "Performance Investigate of Recovery Nylon 6 Membrane Reinforced Nylon 6 Fabric." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/35661169098033097699.
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Hsuan-ShengLin and 林玄昇. "Preparation of Nylon 6 and PEO/Nylon 6 core/shell fibers via electrospinning." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/72319641240245361331.
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Amintowlieh, Yasaman. "Nylon-6/Agricultural Filler Composites." Thesis, 2010. http://hdl.handle.net/10012/5476.
Full textAbstract:
Preparation of thermoplastics composites using engineering thermoplastics and plant fibers or fillers is a technical challenge because the processing temperature of the thermoplastics is generally above the temperature of degradation of plant fibers of fillers. There have been numerous attempts for processing high melting point engineering thermoplastics like Nylon-6 with plant natural fibers and fillers. Low temperature processing methods, fiber modification or addition of additives which drops polymer melting point are some of proposed solutions for this problem.
The objective of this thesis was to develop a formulation using wheat straw (WS) as a reinforcing fiber for Nylon-6. The concentration of WS was 15 wt-%. The thermoplastic composites were prepared by mixing grinded wheat straw and Nylon-6 using a laboratory scale twin-screw extruder; follow by preparation of samples using injection moulding. The strategy investigated in this thesis was utilization of additives to lower the melting point or to decrease the viscosity of Nylon-6. Lithium chloride salt (LiCl) and N-Butyl benzene Sulfon amide plasticizer (N-BBSA) were used as process additives to decrease melting point and to reduce the processing temperature and time.
The addition of the wheat straw (15 wt-%) to the Nylon-6 increased modulus by 26.9 % but decreased the strength by 9.9 %. Effect of different level of these two additives on mechanical, thermal, physical properties and processability of the composite runs were studied. Addition of 4 wt-% LiCl was found to decrease the melting point from 222 °C to 191 °C, to increase modulus by 14 % in comparison to Nylon-6/wheat straw (15 wt-%). However, it decreased the processability and strength by 12.7 %.
Plasticizer was investigated to easing processability and decreasing the degradation by reducing the residence time in the extruder, it does not affect the melting point of Nylon-6. The addition of 4 wt-% of plasticizer (N-BBSA) increased modulus and strength only by 2.6 % and 3 %, respectively, in comparison to Nylon-6/wheat straw (15 wt-%) composites. The results of mechanical properties were used as a benchmark for comparisons among samples with different formulations (levels of additives) to find out levels of LiCl and N-BBSA for the best mechanical properties. It was found that samples with 2 wt-% LiCl and 2 wt-% of N-BBSA had 29.3 % higher tensile modulus than neat Nylon-6, while its strength was almost same as neat Nylon-6 and 6.3 % higher than Nylon-6/WS (15 wt-%). These results were used to correlate the mechanical properties as a function of percentage of salt and plasticizer in the formulation.
Differential scanning calorimetry (DSC) was used to evaluate the percentage of crystallinity and the melting point of the thermoplastic phase and thermal gravimetric analysis (TGA) was used to measure the thermal stability of different formulation. The kinetics of crystallization and degradation were evaluated using results from DSC and TGA, respectively. The activation energy for thermal degradation and the percentage of crystallinity of the thermoplastic composites were correlated to mechanical properties using linear regression. It was found that fiber degradation had a significant effect on strength but the effects of percentage of crystallinity on composites strength were insignificant. On the other hand, the percentage of crystallinity affects stiffness and impact strength. The ductility was a function of both crystallinity and thermal stability.
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Jen-Long, Yeh, and 葉俊龍. "Study on the Kinetics ,Morphology and Properties of Nylon 6- Polyoxypropylene-Nylon 6 Block Copolymers." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/95859945658898983389.
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CHUANG, MIN-HUA, and 莊旻樺. "Preparation of Lightweight Nylon 6 Microspheres." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/x858j2.
Full textAbstract:
碩士國立雲林科技大學
化學工程與材料工程系
107
Nylon features good mechanical properties, wear resistance, chemical resistance, melt flowability, and processability. Its composition has been used in industry, such as additives for coating materials, cosmetics, and pharmaceutical field. In this study, hollow glass microspheres are used as fillers in nylon particles in order to prepare lightweight nylon microspheres. Hollow glass microspheres are widely filled in most types of plastic, ensuring dimensional stability and reducing the weight of materials. The lightweight nylon microspheres were prepared by the solvent removal method and anionic polymerization method. PA6 and PVP were dissolved in formic acid, and mixed with the hollow glass microspheres. Formic acid was slowly removed by vacuum evaporation. PA6 was coated on the hollow glass microspheres. With respect to the anionic polymerization method, caprolactam was gently mixed with the hollow glass microspheres and then polymerized into PA6 in silicone oil. It was found that the particle size depended on in the speed of rotation of the reaction flask. Moreover, different ratio of hollow glass microspheres could reduce the weight of the material. The resulting materials were characterized by XRD, TGA, SEM, and other instruments analyses. The hollow-glass-microsphere incorporation leads to low-density PA6 microspheres but hinders nylon from crystallinity. The best strategy/optimized conditions for monodispersed hybrid microspheres are addition of 2 grams of hollow glass microspheres and the rotating speed of 1020.
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Su, Kuan-Hua, and 蘇冠樺. "Structure and Mechanical Properties of Nylon 6 and Nylon 6/ Montmorillonite Nanocomposites Submitted to Multiple Melt Processing." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/93008777281443435853.
Full textAbstract:
博士逢甲大學
紡織工程所
97
Nylon 6 and nylon 6/montmorillonite nanocomposites were mechanically reprocessed via conventional melt processing procedures in order to allow an easier simulation and determination of the effect of multiple melt processing operations on the structure, morphology, mechanical performance and degradation behaviors of the materials. In the first part, virgin nylon 6 was repetitively processed by an injection molding machine until the 16 processing cycle was completed. Virgin and reprocessed nylon 6 coming from each cycle were characterized to evaluate mechanical and rheological properties to be correlated with the number of processing cycles. Changes in chemical structure, molecular weight, molecular weight distribution, and crystalline behavior were also analyzed after each cycle. GPC results showed that a reduction in the average molecular weight and an increase in the molecular weight distribution as a consequence of a decrement in melt viscosity of nylon 6, but the chemical structure of the nylon 6 remained unchanged in the FTIR spectra. DSC thermal analysis revealed that crystallization rate was increased with increasing reprocessing cycles, and the crystallite size distribution was changed as a consequence of chain scission during reprocessing. The mechanical properties showed that there is an increment in tensile yield stress, flexural strength and modulus after each reprocessing cycle, whereas a decrement in Izod impact strength. Besides, it is observed that nylon 6 specimens became progressively yellow after each cycle due to thermo-oxidative degradation. In the second part, nylon 6 and organic modified montmorillonite (organoclay) were melt compounded using a twin screw extruder to prepare the nylon 6/montmorillonite nanocomposites. Then, the nanocomposites were reintroduced again for further extrusion until the 6 cycle of processing was completed. In this part, neat nylon 6 was also reprocessed as a reference material. In the first step, nylon 6 was melt compounded with a commercial organoclay, Cloisite 20A, to prepare intercalated nanocomposites, which is a good model system for monitoring the morphology evolution of the nanocomposites during multiple processing, because delamination and dispersion in this system is especially sensitive to the process conditions. The parameter studied was the screw speed from 100 to 180 rpm. A combination of XRD and TEM indicated that the dispersion and delamination of the clay particles were improved progressively with the increasing number of processing cycles from intercalation to exfoliation. The molecular weight of both nylon 6 and nylon 6 nanocomposites were decreased with increasing either processing cycles or screw rotation speed due to thermal mechanical degradation. Tensile modulus and yield stress were also found to increase slightly with increasing number of cycles due to better dispersion of the clay. However, elongation at break and notched Izod impact strength of both neat PA6 and PA6 nanocomposites were decreased with increasing number of cycles due to PA6 degradation during reprocessing. In the second step, nylon 6 was melt compounded with two organoclays, Cloisite 20A and Cloisite 30B, and an unmodified clay, Cloisite Na+, to prepare intercalated, exfoliated nanocomposites and conventional microcomposites, respectively. Also, these composites were subjected to multiple melt extrusions to investigate the effect of multiple processing on the structure and mechanical properties of the composites with different morphology. With increasing the melt extrusion cycles, the morphology of the conventional microcomposites was slightly improved, and the morphology of exfoliated nanocomposites was almost remained unchanged, while the intercalated ones were improved progressively, and finally become an exfoliated nanocomposites. The tensile modulus and yield strength of the exfoliated nanocomposites (30B140) were superior to the others, while their elongation at break and impact strength were lower than the intercalated ones (20A140). The mechanical properties of the conventional microcomposites (Na+140) were the worest of the three because of agglomeration of the layered silicates in the composites. With the increases of the melt processing cycles, the modulus of the exfoliated nanocomposites were slightly increased, but their yield strength remained unchanged. Tensile modulus and yield stress of the intercalated ones were increased slightly due to better dispersion of the clay. The elongation at break of both nanocomposites were decreased with the increases of the processing cycles due to thermo-oxidative degradation.
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Ho, Cheng-Yo, and 何承祐. "Mesomorphic intermediate stages during Brill transition of Nylon 6/6." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/58538367110406762747.
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碩士國立清華大學
化學工程學系
102
The Brill transition in nylon 6/6 is generally perceived as a fully reversible solid-solid transformation, with the well-separated (100)α and (010)α reflections in the X-ray diffraction profile merging into a fully overlapped peak of (100/010)γ reflections. However, there is an 8% mismatch between densities of γ and α crystals, from which one would not expect complete conversion via solid-solid transformation. Here we report observations via small/wide-angle X-ray scattering (SAXS/WAXS), Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) on kinetic aspects of the Brill transition in nylon 6/6 during (1) cooling at 10 °C/min from a γ-dominated state at 250 °C to room temperature, (2) reheating at 10 °C/min of a “glassy” specimen quenched from the melt state at 280 °C and (3) isothermal annealing at 130 °C for an α-containing specimen cooled (at 10 °C/min) from the γ-containing melt at 250 °C. For successful deconvolution of WAXS profiles upon cooling, two additional diffraction peaks located in between of (100)α and (010)α positions are needed below 200 °C. Two new IR bands, assigned to symmetric and asymmetric CH2 stretching modes, are observed to emerge at 150 °C, which further grow with decreasing temperature. This signifies the incipient formation of α crystals at 150 °C. The SAXS invariant QSAXS continuously increases from 150 to 110 °C instead of a sigmoidal jump, indicating that the formation of high-density α phase is gradual rather than instantaneous. As both FTIR and SAXS evidences indicate formation of α crystals below 150 °C, the precursory split of the characteristic WAXS peak of the γ phase at q ≈ 1.54 Å−1 below 210 °C can only be attributed to an intermediate form of mesomorphic nature; this is also supported by the anomalous temperature dependence of the two WAXS peaks of the mesophase. Via fitting of SAXS profiles to a model of approximately FCC-packed ellipsoids, the nanodomain shape was observed to change from prolate (250–190 °C) to oblate (180–30 °C) which, in combination with the domain size determined from WAXS profiles, suggests growth along the c-axis due to the gauche-to-trans conformation change during γ-to-mesomorphic phase change. For the as-quenched “glass” at room temperature, deconvolution of the WAXS profile indicates coexistance of mesophase and small α crystals. Upon heating, the mesophase content increases at the full expense of the α phase (with additional contribution from the amorphous phase) from 30 to 90 °C, followed by pleaued mesophase content and then trasformation to γ crystals at 180 °C. In the overlapping temperature range of 30 to 110 °C, 2D correlation maps of N-H stretching bands indicate an increase of disordered H-bonds occurring after the decrease of free H-bonds and ordered H-bonds, consistent with the generation of mesophase from both the α crystals and the amorphous phase. During isothermal annealing at 130 °C of the specimen cooled at 10 °C/min from 250 °C, the two WAXS peaks (contributed from both α crystals and the mesophase) shift outward in opposite directions, suggesting increased (100)α and (010)α intensities upon meso-to-α phase transformation. Quantitative deconvolution results show that the increase of α phase content is contributed by both the decreased mesophase and amorphous phase contents. To summarize, observations in this study indicate that there is always a mesomorphic intermediate during transformation between α and γ forms, hence the Brill transition is not a direct solid-to-solid transformation.
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林建明. "The influence of TiO2 on Nylon 6." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/75873052334476844923.
Full textAbstract:
碩士國立臺灣科技大學
高分子工程系
91
The present research is mainly to study the influential effects on ε-caprolactam Nylon by adding various concentrations of TiO2,and then they are chipped and spinned into fiber. Such an adding process is expected to have the result of Anti-Ultra-Va and enhancement of Polymer Material Properties such as shearing , elongation viscosity, dynamic mechanical property, and Glass Transfer Temperature. The experiment results show that the uses of different concentration of TiO2 for Polymerization Nylon and spinning out Bright、Semi-dull、and Full-dull based fibers, can result in different anti — UV effects. The compound material properties of shearing and shearing rate increase as the mixing concentration increases .The higher adding concentration will dilute the material shear viscosity . After adding TiO2, the material elasticity is enhances. The DCS and SEM measurement is used to detect Glass Transfer Temperature and distribution of adding TiO2.
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CHENG, CHIU PAI, and 邱百正. "Mechanical Properties of Nylon 6-Clay Nanocomposites." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/88123482748523619778.
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碩士逢甲大學
紡織工程學系
87
Nanocomposites are hybrid of an inorganic clay particle, dispersed in the nanometer scale with an organic polymeric matrix. A commercial nylon 6/fluorine mica nanocomposites are mixed with nylon 6 with the composition of mica 0、0.5、1、2、3、4、4.7wt%. DSC, polarized-light microscopy and DMA are obtained for nylon 6 of various mica compositions. Tensile and compression properties are measured at dry and wet room temperature condition. The presence of mica will enhance the strength and modulus of nylon 6. The absorption of water will decrease the mechanical properties. Additional compression properties are performed at various temperatures. The nanocomposites shows a large decrease in compression yield strength and modulus with respect to the temperature. The correlation between yield strength with modulus is not consistent with H-G Elias’ theory. The Hooke number proposed by H-G Elias is analyzed on the tensile break strength of nanocomposites with a very low clay reinforced material present, it reach the He value of traditional reinforced composite materials.
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SHIH, Chang-Chih, and 史長志. "Water Assisted Injection Molding of Nylon 6." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/10315795030588143752.
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碩士長庚大學
機械工程研究所
93
This report was to experimentally study the water assisted injection molding of glass fiber reinforced polyamide-6 (Nylon-6) composites. Experiments were carried out on an 80-ton injection-molding machine equipped with a lab scale water injection system, which included a water pump, a water injection pin, a water tank equipped with a temperature regulator, and a control circuit. The materials used were nylon and 30% glass fiber filled nylon composites. A spiral mold cavity was used to mold the composites. After molding, the lengths of water penetration in molded parts were measured. The effects of different processing parameters on the lengths of water penetration were determined: melt temperature, mold temperature, melt filling speed, short-shot size, water pressure, water temperature, water hold and water injection delay time. Mechanical property tests were performed on the water assisted injection molded parts. XRD has also been employed to identify the structural parameters of the materials. In addition, the in-mold temperature distribution of the polymeric materials during the cooling process was measured. Irregular water penetration in molded parts was observed. Water temperature was found to affect the crystallinity distribution of molded parts. Nevertheless, its effects on the tensile properties of molded materials were relatively limited.
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CHEN, HONG-YI, and 陳弘毅. "Nylon 6/PVA r-ray homografted membrane." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/59990518617797452440.
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Huang, Yi Wei, and 黃翊瑋. "Mechanical properties of nylon 6 artificial muscle." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/qcea4k.
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碩士國立清華大學
材料科學工程學系
105
Artificial muscles from nylon 6 fibers have been widely studied for their low-cost, high-strength, light weight, and high performance. We investigate mechanical properties of nylon 6 artificial muscle including creep, stress relaxation, thermal actuation force, and tensile tests. Shape of nylon 6 artificial muscle can be fixed after annealing, and we apply four different annealing temperatures to study the influence of annealing temperature on mechanical properties. We use standard linear solid model to fit the creep and stress relaxation data, and the relaxation rate (βc and βS) satisfies the Arrhenius equation. The activation energy decreases with increasing annealing temperature. We also investigate the mechanical properties of nylon 6 non-twisted fibers and chicken muscle fibers to evaluate the influence of twist insertion and the difference between natural muscle and artificial muscle. In tensile tests, nylon 6 non-twisted fibers have largest Young’s modulus and chicken muscle fibers have the smallest. In creep tests, these three materials all follow standard linear model, and the relaxation rates (βc) satisfy the Arrhenius equation. Like nylon 6 artificial muscles, the activation energy in the creep test decreases with increasing annealing temperature for nylon 6 non-twisted fibers. The studies of crystallinity show that crystallinity increases with increasing annealing temperature. We discuss the influence of crystallinity on creep tests and stress relaxation.
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Chiu, Kuei-Chen, and 邱貴珍. "A Study of Crystallization Behavior in Nylon 6/6T and Nylon 66/6T copolymers." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/5dknc4.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
97
In this study, there were two topics based on the homopolymer Nylon 6 and Nylon 66 respectively. Crystallization kinetics of the homopolymer and copolymers both have been isothermally and non-isothermally investigated by different scanning calorimetry (DSC) and crystalline microstructure were studied by X-ray diffraction (WAXD). The equilibrium melting point was obtained using the Hoffman-Weeks method. The results show that the equilibrium melting point of Nylon 6/6T was decreased with an increasing Nylon 6T content in Nylon 6. With Avrami analysis, the crystallization rate (k) increased when the temperature increased. And the crystallization rate constant for Nylon 6 and Nylon 6/6T were evaluated. As the Nylon 6T content was reached to 7 mole% the crystallization rate constant was decreased rapidly. The transition temperature between Regime III and Regime II, obtained using the Lauritizen-Hoffman method, was found to be lower for Nylon 6/6T copolymer than the matrix Nylon 6. With WAXD, the model specimens were found to contain α form and γ form in Nylon 6/6T-7% and Nylon 6/6T-10%. Secondly the other system Nylon 66 and Nylon 66/6T, it was found that not only the equilibrium melting point and the crystallization rate (k) but also the transition temperature between Regime III and Regime II, which were similar to Nylon 66. The WAXD patterns were found to be unchanged.