Academic literature on the topic 'In-situ polymerizations'
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Journal articles on the topic "In-situ polymerizations"
Goto, Atsushi, Koji Nagasawa, Ayaka Shinjo, Yoshinobu Tsujii, and Takeshi Fukuda. "Reversible Chain Transfer Catalyzed Polymerization of Methyl Methacrylate with In-Situ Formed Alkyl Iodide Initiator." Australian Journal of Chemistry 62, no. 11 (2009): 1492. http://dx.doi.org/10.1071/ch09229.
Full textMonroy, V. M., G. Guevara, I. Leon, A. Correa, and R. Herrera. "In-situ Titration of Initiator-Consuming Impurities in Solution Anionic Polymerization." Rubber Chemistry and Technology 66, no. 4 (September 1, 1993): 588–93. http://dx.doi.org/10.5254/1.3538331.
Full textOgata, Naoya. "Micro-composite systems by in-situ polymerizations." Macromolecular Symposia 83, no. 1 (May 1994): 1–11. http://dx.doi.org/10.1002/masy.19940830103.
Full textFu, F. S., and J. E. Mark. "Polystyrene–polyisobutylene network composites from in situ polymerizations." Journal of Applied Polymer Science 37, no. 9 (May 5, 1989): 2757–66. http://dx.doi.org/10.1002/app.1989.070370924.
Full textWang, Jin-Tao, Yanhang Hong, Xiaotian Ji, Mingming Zhang, Li Liu, and Hanying Zhao. "In situ fabrication of PHEMA–BSA core–corona biohybrid particles." Journal of Materials Chemistry B 4, no. 25 (2016): 4430–38. http://dx.doi.org/10.1039/c6tb00699j.
Full textJiang, Hejin, Qingxian Jin, Jing Li, Shuyu Chen, Li Zhang, and Minghua Liu. "Photoirradiation-generated radicals in two-component supramolecular gel for polymerization." Soft Matter 14, no. 12 (2018): 2295–300. http://dx.doi.org/10.1039/c8sm00153g.
Full textMelo, Caio K., Matheus Soares, Carlos A. Castor, Príamo A. Melo, and José Carlos Pinto. "In Situ Incorporation of Recycled Polystyrene in Styrene Suspension Polymerizations." Macromolecular Reaction Engineering 8, no. 1 (September 16, 2013): 46–60. http://dx.doi.org/10.1002/mren.201300144.
Full textSchmitt, M. "Method to analyse energy and intensity dependent photo-curing of acrylic esters in bulk." RSC Advances 5, no. 82 (2015): 67284–98. http://dx.doi.org/10.1039/c5ra11427f.
Full textCastor, Carlos A., Márcio Nele, and José Carlos Pinto. "In-Situ Incorporation of Poly(methyl methacrylate) in Suspension Styrene Polymerizations." Macromolecular Reaction Engineering 8, no. 8 (June 11, 2014): 580–96. http://dx.doi.org/10.1002/mren.201400007.
Full textWang, Xinnan, Ting Han, Jacky W. Y. Lam, and Ben Zhong Tang. "In Situ Generation of Heterocyclic Polymers by Triple‐Bond Based Polymerizations." Macromolecular Rapid Communications 42, no. 24 (October 28, 2021): 2100524. http://dx.doi.org/10.1002/marc.202100524.
Full textDissertations / Theses on the topic "In-situ polymerizations"
DISTEFANO, GAETANO. "Nanoporous dipeptide crystals as selective gas sorbents and polymerization nanovessels." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/29103.
Full textCarvalho, Fabiana Pires de. "Blendas de poli(metacrilato de metila) e do elastômero saturado poli(acrilonitrila-g-(etileno-co-propileno-co-dieno-g-estireno) obitdas por polimerização in situ." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248777.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo:Neste trabalho foram preparadas e caracterizadas blendas de poli(metacrilato de metila), PMMA e poli[acrilonitrila-g-(etileno-co-propileno-co-dieno)-g-estireno], AES. O AES é um polímero amorfo e um material complexo, composto de uma mistura de poli(etileno-co-propileno-co-2-etilideno-5-norboneno) (EPDM), poli(estireno-coacrilonitrila) (SAN), e copolímero de enxertia EPDM-g-SAN. As blendas PMMA-AES foram obtidas por polimerização in situ, tendo-se como variáveis o solvente, agitação e atmosfera inerte, a fim de avaliar a influência destas sobre as propriedades estruturais e morfológicas das blendas. As blendas foram caracterizadas por espectroscopia infravermelho (IV), ressonância magnética nuclear de C (RMN de C), microscopia eletrônica de varredura (SEM), microscopia eletrônica de transmissão (TEM), análise dinâmico-mecânica (DMA) e resistência ao impacto. Os resultados mostraram que as blendas são imiscíveis apresentando uma morfologia complexa de domínios elastoméricos dispersos em uma matriz vítrea, dependente das condições de polimerização. Em algumas blendas, uma fração de PMMA encontra-se incluso na fase elastómerica, sugerindo uma morfologia tipo core shell ou tipo salame. Porém, essa morfologia complexa é afetada após o processo de injeção, devido ao efeito de temperatura e de cisalhamento. Extração seletiva e análise por espectroscopia infravermelho dos componentes das blendas mostraram que ocorre enxertia e/ou reticulação durante a polimerização. A sindiotaticidade do PMMA obtido em presença de AES aumenta com a quantidade de AES na blenda, devido às possíveis interações entre os grupos carbonilas do PMMA e os grupos nitrilas e fenilas da fase SAN. As blendas PMMA-AES apresentam propriedades mecânicas dependentes do teor de AES, sendo a resistência ao impacto das blendas superiores a do PMMA puro. Ensaios de envelhecimento fotoquímico acelerado mostraram que as blendas PMMA-AES apresentam queda na resistência ao impacto após envelhecimento
Abstract: In this work, blends of the poly(methyl methacrylate), PMMA, and the poly[acrylonitrile-g-(ethylene-co-propylene-co-diene)-g-styrene], AES, were prepared. AES is a complex mixture of poly(styrene-co-acrylonitrile), SAN, and poly(ethylene-copropylene-co-diene), EPDM, and the graft copolymer EPDM-g-SAN. Blends PMMA-AES were obtained by polymerization in situ, varying the solvent, the agitation and the inert atmosphere in order to evaluate their influence on the morphological and structural properties of the blends. The blends were characterized by infrared spectroscopy (FTIR), carbon-13 nuclear magnetic resonance (C NMR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic mechanical analysis (DMA) and Izod impact resistance test. The results showed that the PMMA-AES blends are immiscible and present a complex morphology. The morphology of some PMMA-AES blends is made up of an elastomeric dispersed phase in the glassy matrix, with inclusion of the matrix in the EPDM domains, suggesting core shell or salami morphology. However, this morphology is affected by the moulding injection process, due the temperature and shear effects. The selective extraction of the blends¿ components and the infrared spectroscopy showed that crosslinked and/or grafting reactions occur on EPDM chains during MMA polymerization. The syndiotactic PMMA obtained in the presence of AES increases with the amount of AES, due to the possible interaction among the carbonyl groups of PMMA and the nitrile or phenyl groups of SAN copolymer. The mechanical properties of the blends were influenced by the composition of the blend and the impact strength of the blends is superior to near PMMA. Photochemical aging tests showed that PMMA-AES blends presented decrease in the impact strength after aging
Doutorado
Físico-Química
Doutor em Ciências
Macêdo, Neto José Costa de. "Produção e caracterização de nanocompósitos poliméricos obtidos por polimerização em emulsão utilizando Caulinita Amazônica." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266818.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Materiais nanocompósitos poliméricos utilizando argilas naturais como reforço tem sido bastante estudados por apresentar propriedades melhoradas em relação ao polímero sem reforço. Este trabalho tem como objetivo produzir e caracterizar materiais nanocompósitos polimérico com matriz de poliestireno por meio da polimerização in situ em emulsão utilizando com nanopartícula a caulinita amazônica. Os resultados obtidos mostraram que a caulinita utilizada como reforço neste trabalho apresentou alta razão de aspecto, foi possível ser intercalada por moléculas orgânicas de dimetilsulfóxido (DMSO) e acetato de potássio (AcK). Nesta tese foram produzidos nanocompósitos com 1, 3 e 5% de caulinita modificada com DMSO e outros com 1, 3 e 5% de argila modificada com AcK. A estabilidade do látex produzido pela polimerização foi medida por dynamic light scattering (DLS). O látex com 3% de argila modificada com DMSO apresentou melhor estabilidade em relação ao com 1% de argila e ao do poliestireno puro. As análises por difração de raios X (DRX) e microscopia eletrônica de varredura de alta resolução (HRSEM) revelaram que a utilização das quantidades 1 e 3% de argila modificada com DMSO são as ideais para a obtenção de nanocompósitos. A análise termogravimétrica (TGA) dos nanocompósitos com 1 e 3% apresentou melhores propriedades térmicas em relação ao polímero sem reforço. A análise por calorimetria exploratória diferencial (DSC) mostrou que a adição de 1 e 3% de argila não alterou a temperatura de transição vítrea em relação ao polímero sem reforço. A análise térmica dinâmico-mecânica (TDMA) mostrou que o módulo de armazenamento (E') foi maior para o poliestireno puro em relação aos nanocompósitos com 1 e 3% de argila durante o aquecimento. A TDMA também mostrou que a adição de 1 e 3% de argila não influenciou a temperatura de transição vítrea (Tg). O ensaio de inflamabilidade horizontal mostrou que a taxa de queima foi menor para o nanocompósito com 3% de argila em relação ao PS e 1%. Sendo assim, foi possível produzir nanocompósitos com a caulinita. O látex obtido com 3% de argila foi o mais estável. Os nanocompósitos com quantidades de1 e 3% de argila obtiveram melhores propriedades térmicas em relação ao poliestireno sem argila. O PS puro apresentou maior E' as quantidades de 1 e 3% de argila não influenciou a Tg. O nanocompósito com 3% de argila obteve menor taxa de queima
Abstract: Polymer nanocomposites materials using natural clays as reinforcement has been extensively studied by presenting improved properties compared to unreinforced polymer. The goal of This work is to produce and characterize a polymer nanocomposites materials with matrix od polystyrene and nanoparticle by kaolinite through in situ emulsion polymerization. The kaolinite used as reinforcement in this study had a high aspect ratio, could be intercalated by organic molecules of dimethylsulfoxide (DMSO) and potassium acetate (ACK). In this thesis were produced nanocomposites with 1, 3 and 5% kaolinite modified with DMSO and others with 1, 3 and 5% clay modified with AcK. The stability of the latex produced by polymerization was measured by dynamic light scattering (DLS). Latex with 3% clay modified with DMSO showed better stability compared with the 1% clay and the pure polystyrene. Analyses by X-ray diffraction (XRD) and scanning electron microscopy, high resolution (HRSEM) revealed that use of the quantities 1 and 3% clay modified with DMSO are ideal for obtaining nanocomposites. The thermogravimetric analysis (TGA) of the nanocomposites with 1 and 3% showed better thermal properties compared to unreinforced polymer. Analysis by differential scanning calorimetry (DSC) showed that the addition of 1 and 3% clay did not change the glass transition temperature compared to the unreinforced polymer. The dynamic mechanical thermal analysis (TDMA) showed that the storage modulus (E') was higher for the pure polystyrene compared to nanocomposites with 1 and 3% clay during heating. TDMA also showed that the addition of 1 and 3% clay did not influence the glass transition temperature (Tg). The horizontal flammability test showed that the burn rate was lower for the nanocomposite with 3% clay compared to PS and 1%. Therefore, it was possible to produce nanocomposites with kaolinite. The latex obtained with 3% clay was the most stable. Nanocomposites with quantities of 1 and 3% clay had better thermal properties compared to polystyrene clay. The pure PS had a higher E' quantities of 1 and 3% clay did not affect the Tg. The nanocomposite with 3% clay had lower burn rate
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química
Cocco, Daniel Rotella. "Blendas de poli(metracrilato de metila) e do elastômero ASA obtidas por polimerização in situ." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248768.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química.
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Resumo: Neste trabalho foram preparadas e caracterizadas blendas de poli(metacrilato de metila), PMMA, e poli[acrilonitrila-co-acrilato de butila], ASA. O ASA é um polímero amorfo e constituído de uma mistura de poli(acrilato de butila) (PBA) e poli(estireno-co-acrilonitrila) (SAN). As blendas PMMA-ASA foram obtidas por polimerização in situ, tendo sido estudada a influência do agente de transferência de cadeia, da agitação e da atmosfera inerte sobre as propriedades estruturais e morfológicas das blendas. As blendas foram caracterizadas por cromatografia de permeação em gel (GPC), espectroscopia infravermelho (IV), análise termogravimétrica (TGA), ressonância magnética nuclear de C (RMN de C), análise dinâmico-mecânica (DMA), microscopia eletrônica de varredura (SEM), microscopia eletrônica de transmissão (TEM), e resistência ao impacto e tração. Os resultados mostraram que as blendas são imiscíveis apresentando uma morfologia complexa de domínios elastoméricos dispersos em uma matriz vítrea, dependente das condições de polimerização. Em algumas blendas, uma fração de PMMA encontra-se possivelmente inclusa na fase elastómerica, sugerindo uma morfologia tipo core shell ou tipo salame. Porém, essa morfologia complexa é afetada após o processo de injeção para algumas blendas, devido ao efeito de temperatura e de cisalhamento. Extração seletiva e análise por espectroscopia infravermelho dos componentes das blendas mostraram que ocorre enxertia e/ou reticulação durante a polimerização. A sindiotaticidade do PMMA obtido em presença de ASA aumenta com a quantidade de ASA na blenda, devido às possíveis interações entre os grupos carbonilas do PMMA e os grupos nitrilas e fenilas da fase SAN. As blendas PMMA-ASA apresentam propriedades mecânicas dependentes do teor de ASA e das condições de preparo, sendo a resistência ao impacto das blendas superiores à do PMMA puro
Abstract: In this work, blends of the poly(methyl methacrylate), PMMA, and the poly[acrylonitrile-co-styrene-co-butyl acrylate], ASA, were prepared. ASA is a complex mixture of poly(styrene-co-acrylonitrile), SAN, and poly(butyl acrylate), PBA. Blends PMMA-ASA were obtained by polymerization in situ, and the influence of a chain transfer agent, stirring and the inert atmosphere on the morphological and structural properties of the blends was studied. The blends were characterized by gel permeation chromatography (GPC), infrared spectroscopy (FTIR), C nuclear magnetic resonance ( C NMR), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), lzod impact resistance test and tensile tests. The results showed that the PMMA-ASA blends are immiscible and present a complex morphology. The morphology of some PMMA-ASA blends is made up of an elastomeric dispersed phase in the glassy matrix, with a possible inclusion of the matrix in the elastomeric domains, suggesting core shell or salami morphology. However, this morphology is affected by the moulding injection process, for some blend compositions, due the temperature and shear effects. The selective extraction of the blends components and the infrared spectroscopy showed that crosslinked and/or grafting reactions occur on ASA chains during MMA polymerization. The syndiotacticity of PMMA obtained in the presence of ASA increases with the amount of ASA, due to the possible interaction among the carbonyl groups of PMMA and the nitrile or phenyl groups of SAN copolymer. The mechanical properties of the blends were influenced by the composition of the blend and conditions of polymerization, and the impact strength of the blends is superior to neat PMMA
Mestrado
Físico-Química
Mestre em Química
Figueiredo, Ana Rita Parente. "Novel bacterial cellulose nanocomposites prepared through in situ polymerization." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11662.
Full textA celulose é o polissacarídeo mais abundante na Natureza, sendo o principal componente estrutural das plantas, e com uma importância industrial elevada principalmente na indústria papeleira e têxtil. Para além das plantas, a celulose é também produzida por algumas bactérias sendo designada de celulose bacteriana (BC). A BC apresenta propriedades únicas, como a elevada retenção de água, resistência mecânica, biodegradabilidade e biocompatibilidade, que tem atraído enorme atenção em diversas áreas. Uma das principais aplicações da BC é o desenvolvimento de nanocompósitos, com aplicações desde a área biomédica, como moldes para engenharia de tecidos, até áreas mais técnicas, como materiais de embalagem. Assim, este trabalho descreve a preparação de nanocompósitos de celulose bacteriana e poli(metacrilato de 2-aminoetilo) (PAEM) por polimerização radicalar in situ, com quantidades variáveis de N,N-metilenobis(acrilamida) (MBA) como reticulande. Deste processo resultaram filmes nanocompósitos mais transparentes que a BC com propriedades mecânicas melhoradas assim como maior estabilidade térmica, em relação aos polímeros puros. Para além disso, os nanocompósitos apresentam elevada capacidade de reabsorção de água após secos e cristalinidade reduzida, relativamente à BC pura, devido à incorporação do polímero amorfo. A atividade antibacteriana nos nanocompósitos foi também avaliada utilizando E. coli bioluminescente, tendo-se verificado que apenas o nanocompósito não reticulado (BC/PAEM) apresenta actividade antibacteriana.
Cellulose is the most abundant polysaccharide in Nature being the main structural component in plants, and having a high economic importance, namely in paper and textile industries. Besides plants, cellulose is also produced by some bacteria, the so called bacterial cellulose (BC). BC has unique properties such as high water holding ability, mechanical strength, biodegradability and biocompatibility; that attracted its attention towards several fields. One of the BC applications is the development of nanocomposite materials, with applications ranging from biomedical field, as tissue scaffolds, to more technical fields such as packaging materials. So, the aim of this work was to prepare bacterial cellulose-poly(2-aminoethyl methacrylate) (PAEM) nanocomposites by in situ radical polymerization, using variable amounts of N,N-methylenebis(acrylamide) (MBA) as crosslinker agent. Several nanocomposite films were prepared, showing to be significantly more transparent than BC, with improved mechanical properties and thermal stability, in comparison with the pristine polymers. Furthermore, the nanocomposite materials show high swelling ability in water after drying as well as decreased crystallinity, in comparison with pure BC, as a result of the incorporation of amorphous polymer. The antibacterial activity of the nanocomposites prepared was also assessed towards bioluminescent E. coli from which only the non-crosslinked nanocomposite (BC/PAEM) showed to have antibacterial activity.
Herrera-Alonso, Jose M. "Polymer/Clay Nanocomposites as Barrier Materials Used for VOC Removal." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/28933.
Full textPh. D.
Botan, Rodrigo 1982. "Sintese e caracterização de nanocompositos de poliestireno - hidroxido duplo lamelar via polimerização in situ." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267081.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Ao longo da última década, nanocompósitos poliméricos vêm atraindo grande atenção da comunidade científica e industrial. Este fato se deve a notável melhora em inúmeras propriedades que estes novos materiais apresentam com uma pequena quantidade de nano-reforços. Algumas das propriedades melhoradas incluem resistência a permeação de gases e resistência a chama. Neste trabalho foram sintetizados dois tipos de hidróxido duplo lamelar (HDL), tratados com dodecil sulfato de sódio (DS), com o objetivo de incorporá-los ao estireno e sintetizar in situ nanocompósitos de Poliestireno - Hidróxido Duplo Lamelar - Dodecil Sulfato de Sódio (PS-HDL/DS). Os hidróxidos duplos lamelares tratados com dodecil sulfato de sódio (HDL/DS) foram sintetizados pelo método de co-precipitação e os nanocompósitos foram produzidos por polimerização em massa. Estes hidróxidos duplos lamelares tratados com dodecil sulfato de sódio foram caracterizados por teste de inchamento Foster, difração de raios-X (DRX) e espectroscopia no infravermelho por transformada de Fourier (FTIR). Os nanocompósitos foram caracterizados por difração de raios-X (DRX), espectroscopia no infravermelho por transformada de Fourier (FTIR), microscopia eletrônica de transmissão (MET), análise termogravimétrica (TGA) e teste de inflamabilidade. A partir dos resultados obtidos neste trabalho, verificou-se que os nanocompósitos sintetizados apresentaram uma ótima interação (esfoliação) polímero - hidróxido duplo lamelar. Dentre as propriedades dos dois novos nanocompósitos sintetizados, a resistência à chama (anti-chama), apresentou um ganho significativo quando comparada com o polímero puro, fato que possibilita uma vasta gama de aplicação destes novos materiais em diversos campos da engenharia
Abstract: Over the past decade, polymer nanocomposites have attracted considerable interests in both academia and industry. This fact has connection with notable improvement in several properties these new materials have demonstrated with a small amount of nano-reinforcements. Some superior properties of polymer nanocomposites include barrier resistance and flame retardancy. The aim of this work was to synthesize two kinds of layered double hydroxide (LDH) modified with sodium dodecyl sulfate (SDS). Both layered double hydroxides (LDHs) were incorporated into styrene by bulk free radical polymerization in order to produce the nanocomposites polystyrene - layered double hydroxide - sodium dodecyl sulfate (PS - LDH/SDS). The layered double hydroxides modified with sodium dodecyl sulfate (LDH/SDS) were prepared by co-precipitation method and the nanocomposites have been synthesized by bulk free radical polymerization. These layered double hydroxides modified with sodium dodecyl sulfate were characterized by Foster swelling, X - rays diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) and the nanocomposites were characterized by X -rays diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and flammability test. These new materials formed in this work showed great interaction polymer -layered double hydroxide (exfoliation) as well as excellent improvements on their properties when compared with pure polymer. The property flame retardancy showed improvements in the two nanocomposites synthesized and in all ratios studied, this behavior induces application of these new materials in many fields of engineering
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
Walmet, Eric Robert. "In-situ monitoring of PMMA solution polymerization with dielectric microsensors." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/10036.
Full textSoltan, Omar. "Polypropylene/filler nanocomposites by melt compounding and in situ polymerization." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5310.
Full textENGLISH ABSTRACT: The properties of polymer nanocomposites depend greatly on the chemistry of the polymer matrices, the nature of the nanofillers, and the way in which they are prepared. Understanding the synthesis–structure–property relationship of nanocomposites is vital for the development of advanced polymer nanocomposites with enhanced mechanical strength, stiffness and toughness for structural engineering applications. To this end, the primary aim of this study was to determine the impact that the preparation methods have on the properties of PP/filler nanocomposites, with specific focus on the in situ polymerization of propylene via the methylaluminoxane (MAO) activated metallocene catalyst technique. Two different fillers (Silica and Calcium carbonate) were used as support for the metallocene catalysts. Different supporting methodologies for the synthesis of the supported catalyst were examined. A C2 symmetric metallocene catalyst ansa dimethylsilylbis(2-methyl benzoindenyl) zirconium dichloride (MBI) was used in this study. The catalyst systems were then evaluated for propylene polymerization. The early observation shows that a direct adsorption of the metallocene onto the filler has a diminishing effect on the catalyst productivity and the fillers had to be treated with MAO in order to avoid catalyst deactivation by the filler surface. Due to the low productivity of the supported active species, the presence of soluble catalyst active species, besides the supported active species is required in the synthesis of PP nanocomposites via in situ polymerizations. The syntheses of PP nanocomposites were carried out via in situ polymerization in which different quantities of MAO treated fillers were reacted with pre-activated catalyst solution. The effect of the addition of MAO-filler on the polymerization kinetics and consequently on PP matrix microstructure was investigated. Changes in the in situ polymerization kinetics, compared to kinetics of homogeneous polymerization, were observed. Therefore, the microstructure of the polymer matrix was also influenced by the presence of nanofillers in the polymerization media. The influence of the different synthesis methods on the performance of the nanocomposites was investigated using melt-mixed PP/filler nanocomposites obtained using PP homopolymer. The dispersed phase morphologies of the different nanocomposites were investigated by transmission electron microscopy (TEM). Results show that PP nanocomposites with improved filler dispersion were achieved by in situ polymerization compared to melt-mixed nanocomposites. The influence of the synthesis method on the crystallization behaviour of PP nanocomposites was also investigated. It was found that, for the in situ prepared nanocomposites the tacticity of the PP matrix plays the major role in determining the degree of crystallinity. Results also show that when nanocomposites with comparable PP matrices are compared, the overall crystallization rate of the in situ polymerized nanocomposites is higher than that of the melt mixed nanocomposites. The mechanical properties of in situ polymerized PP and melt mixed PP nanocomposite were also investigated and compared. Due to improved nanoparticle dispersion in the PP matrix, in situ polymerized nanocomposites show enhanced mechanical properties, especially tensile and impact properties, compared to pure PP and melt mixed prepared nanocomposites when a PP matrix of equivalent microstructure was used. Finally, the melt compounding method was further investigated using different fillers and commercial PP as a matrix. The effect of filler type, size and applied surface coating on the flow and mechanical properties of PP nanocomposites was studied. The aim of this part of this study is to obtain a good trade-off between the processability and the mechanical properties and to gain insight into the cause of the emergence of different properties for nanocomposites prepared by melt compounding.
AFRIKAANSE OPSOMMING: Die eienskappe van polimeer nanokomposiete hang grotendeels af van die chemie van die polimeer matriks, die wese van die nano-vullers, en die manier waarop hierdie materiale berei word. Om die sintese-struktuureienskap verwantskap te verstaan is noodsaaklik vir die ontwikkeling van gevorderde nanokomposiete met beter meganiese eienskappe, styfheid en taaiheid vir strukturele ingenieurstoepassings Die primêre doelstelling van hierdie studie was dus om die impak van voorbereidingsmetodes op die eienskappe van PP/vuller nanokomposiete te bestudeer, met spesifieke fokus op die in-situ polimerisasie van propileen met metiel alumoksaan-geativeerde metalloseen kataliste. Twee verskillende vullers (silika en kalsium karbonaat) is gebruik as ondersteuning vir die metalloseen kataliste. Verskillende metodiek is gebruik om die ondersteunde kataliste te berei. ‘n C2 simmetriese metalloseen katalis ansa-dimetielsiliel(2-metiel bensoindeniel) sirkonium dichloride (MBI) is in die studie gebruik. Die katalissisteme is daarna evalueer vir propileen polimerisasie. Daar is oorspronklik vasgestel dat direkte adsorpsie van die metalloseen op die vuller ‘n negatiewe effek op die katalis aktiwiteit gehad het, en dat die vuller oppervlak eers met MAO behandel moes word om deaktivering van die katalis deur die vuller-oppervlak te vermy. As gevolg van die lae aktiwiteit van die ondersteunde aktiwe katalisspesies, is die teenwoordigheid van opgeloste aktiewe katalis nodig vir die voorbereiding van PP nanokomposiete via in situ polimerisasie-reaksies. Die sintese van PP nanokomposiete is uitgevoer deur in –situ polimersiasie waartydens verskillende hoeveelhede MAO-behandelde vullers gereageer is met vooraf-geaktiveerde katalis oplossings. Die effek van die byvoeging van MAO-vuller op die polimerisasie-kinetika en gevolglik op die PP matriks mikrostruktuur is ondersoek. Dit is gevind dat die mikrostruktuur van die polimeer-matriks beinvloed word deur die teenwoordigheid van nanovullers in die polimerisasie-medium. Die invloed van verskillende bereidingsmetodes op die eienskappe van die nanokomposiete is ondersoek deur smelt-vermengde PP/vuller nanokomposiete te maak. Die dispersie-fase morfologie van verskillende nanokomposiete is ondersoek deur transmissie elektron mikroskopie (TEM). Resultate wys dat PP nanokomposiete met verbeterde vuller-dispersie berkry is deur in situ polimerisasie in vergelyking met die smelt-vermengde materiale. Die effek van die sintese-metode op die kristallisasie van die PP nanokomposiete is ook ondersoek. Daar is gevind dat, vir die in situ bereide nanokomposiete, die taktisiteit van die PP matriks die grootste rol speel in die bepaling van die persentasie kristalliniteit. Resultate het ook gewys dat, wanneer nanokomposiete met soortgelyke PP matrikse vergelyk word met die in situ nanokomposiete, die laasgenoemde se tempo van kristallisasie hoer is as vir die smelt-vermengde nanokomposiete. Die meganiese eienskappe van die in situ bereide en smelt-vermengde PP nanokomposiete is ook ondersoek en vergelyk. As gevolg van verbeterde nano-partikel dispersie in die PP matriks, het die in situ bereide nanokomposiete beter meganiese eienskappe openbaar, in vergelyking met die smelt-vermenge nanokomposiete, veral trek- en slagsterkte. . Laastens is die smelt-vermengings metode verder ondersoek deur gebruik te maak van verskillende vullers en kommersiële PP as matriks. Die effek van die tipe vuller, die grootte en die oppervlakbedekking van die vullerpartikels op die vloei en meganiese eienskappe van die PP nanokomposiete is ondersoek. Die doel van hierdie studie was om ‘n balans te kry tussen prosesseerbaarheid en meganiese eienskappe en om insig te verkry oor die verskille in eienskappe wat openbaar word wanneer smeltvermengde nanokomposiete bereie word.
Lourenço, Emerson. "Sintese e caracterização de poliestireno de alto impacto a base de elastomeros saturados de EPDM." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248780.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O poliestireno de alto impacto (HIPS) apresenta uma ampla variedade de utilização na indústria automobilística. Porém, a sua utilização é limitada, devido à degradação foto-oxidativa de sua fase elastomérica que apresenta alto grau de insaturações. Neste contexto, o objetivo deste trabalho foi preparar e caracterizar blendas de poliestireno com os elastômeros saturados: poli(etileno-co-propileno-co-2-etilideno-5-norboneno) (EPDM) e poli(acrilonitrila-g-EPDM-g-estireno) (AES), visando a obtenção de um material com boas propriedades mecânicas e resistente à degradação fotoquímica. As blendas foram obtidas por polimerização in situ nas temperaturas de 60 °C e 80 °C. As blendas PS/AES e PS/EPDM são imiscíveis. As blendas não injetadas preparadas neste trabalho apresentam uma morfologia que consiste em glóbulos de PS ou PS/SAN envoltos em uma fina película de EPDM para blendas de PS/EPDM e PS/AES, respectivamente. Após o processo de injeção, as blendas passam a apresentar uma morfologia de fase elatomérica dispersa (EPDM) em uma matriz rígida. A maioria das blendas PS/AES e PS/EPDM apresenta maior estabilidade térmica e termo-oxidativa do que o PS puro e a degradação destes materiais é influenciada pela composição e temperatura de polimerização. Os resultados apresentados neste trabalho evidenciam a maior resistência à degradação fotoquímica das blendas PS/AES e PS/EPDM em comparação com o HIPS comercial. Um importante resultado das blendas é que as suas propriedades pós-envelhecimento são superiores às propriedades do HIPS envelhecido. Portanto, o objetivo de preparação de um material mais resistente ao envelhecimento fotoquímico foi alcançado.
Abstract: High impact polystyrene (HIPS) shows a wide range of application in automotive industry, however its utilization is restricted by the photooxidative degradation of the elastomeric phase that contains high degree of unsaturation. In this way, the aim of this work was to prepare and characterize in situ polymerized blends of polystyrene (PS) with saturated elastomers: poly(ethylene-co-propylene-co-2-ethylidene-5-norbomene) (EPDM) and poly(acrylonitrile-g-EPDM-g-styrene) (AES), aiming the preparation of a material with good mechanical properties and higher resistance to photodegradation. The blends were prepared by in situ polymerization at 60 °C and 80 °C. The PS/AES and PS/EPDM blends are immiscible. The non injected blends prepared in this work present a morphology that consists of PS or PS/SAN globes covered by a thin layer of EPDM for PS/EPDM and PS/AES blends, respectively. Whereas the injected blends show a morphology of elastomeric dispersed phase into a rigid matrix. The PS/AES and PS/EPDM show higher thermal and thermo-oxidative stability than PS, and the blend's composition and polymerization's temperature influences the degradation of these materials. The results showed in this work evidence the higher photochemical resistance PS/AES and PS/EPDM blends in comparison with commercial HIPS. An important feature of blends is that their properties after aging are superior than photoaged HIPS properties. Hence, the goal of preparing a material with higher resistance to photochemical aging than HIPS was achieved.
Doutorado
Físico-Química
Doutor em Ciências
Books on the topic "In-situ polymerizations"
Mittal, Vikas. In-situ synthesis of polymer nanocomposites. Weinheim: Wiley-VCH, 2011.
Find full textE, Puskas Judit, ed. In-situ spectroscopy of monomer and polymer synthesis. New York: Kluwer Academic/Plenum Publishers, 2003.
Find full textMittal, Vikas. In-Situ Synthesis of Polymer Nanocomposites. Wiley & Sons, Incorporated, John, 2011.
Find full textMittal, Vikas. In-Situ Synthesis of Polymer Nanocomposites. Wiley-VCH Verlag GmbH, 2011.
Find full textMittal, Vikas. In-Situ Synthesis of Polymer Nanocomposites. Wiley & Sons, Incorporated, John, 2011.
Find full textMittal, Vikas. In-Situ Synthesis of Polymer Nanocomposites. Wiley & Sons, Incorporated, John, 2012.
Find full textLong, Timothy E., Judit E. Puskas, and Robson F. Storey. In Situ Spectroscopy of Monomer and Polymer Synthesis. Springer London, Limited, 2012.
Find full text(Editor), Judit E. Puskas, Timothy E. Long (Editor), and Robson F. Storey (Editor), eds. In-Situ Spectroscopy of Monomer and Polymer Synthesis. Springer, 2003.
Find full textBook chapters on the topic "In-situ polymerizations"
Stokes, Casey D., and Robson F. Storey. "Investigation of High Temperature Isobutylene Polymerizations Utilizing Real-Time ATR-FTIR Spectroscopy." In In Situ Spectroscopy of Monomer and Polymer Synthesis, 59–66. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4615-0125-1_4.
Full textLanzendörfer, M. G., H. Schmalz, V. Abetz, and A. H. E. Müller. "Application of FT-NIR Spectroscopy for Monitoring the Kinetics of Living Polymerizations." In In Situ Spectroscopy of Monomer and Polymer Synthesis, 67–81. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/978-1-4615-0125-1_5.
Full textBoussia, Anastasia C., Stamatina N. Vouyiouka, and Constantine D. Papaspyrides. "Polyamide Nanocomposites by In-situ Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 27–51. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch2.
Full textLeone, Giuseppe, and Giovanni Ricci. "Polybutadiene Clay Nanocomposites by In-situ Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 283–301. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch11.
Full textManeshi, Abolfazl, João Soares, and Leonardo Simon. "Polyolefin-Clay Nanocomposites by In-situ Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 53–88. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch3.
Full textDeng, Hua, Ke Wang, Qin Zhang, Feng Chen, and Qiang Fu. "PET Clay Nanocomposites by In-situ Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 105–22. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch5.
Full textKedzierski, Michal. "Unsaturated Polyester-Montmorillonite Nanocomposites by In-situ Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 245–66. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch9.
Full textZhao, Hanying. "Polymer Clay Nanocomposites by In-situ Atom Transfer Radical Polymerization." In In-Situ Synthesis of Polymer Nanocomposites, 267–81. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch10.
Full textLi, Zhongrui, and Liqiu Zheng. "P3HT-MWNT Nanocomposites by In-situ Polymerization and Their Properties." In In-Situ Synthesis of Polymer Nanocomposites, 303–29. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch12.
Full textSimons, Ranya, Greg G. Qiao, and Stuart A. Bateman. "Polystyrene-Montmorillonite Nanocomposites by In-situ Polymerization and Their Properties." In In-Situ Synthesis of Polymer Nanocomposites, 331–65. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527640102.ch13.
Full textConference papers on the topic "In-situ polymerizations"
Liu, R. H., Q. Yu, J. M. Bauer, J. S. Moore, and D. J. Beebe. "Hydrogel Microvalves Fabricated Using In-situ Polymerization." In 2000 Solid-State, Actuators, and Microsystems Workshop. San Diego, CA USA: Transducer Research Foundation, Inc., 2000. http://dx.doi.org/10.31438/trf.hh2000.54.
Full textForghani, A., L. Garber, C. Chen, R. Devireddy, J. Pojman, and D. Hayes. "In Situ Polymerization of PEGDA Foam for Bone Defects." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51235.
Full textHonnet, Cedric, Hannah Perner-Wilson, Marc Teyssier, Bruno Fruchard, Jürgen Steimle, Ana C. Baptista, and Paul Strohmeier. "PolySense: Augmenting Textiles with Electrical Functionality using In-Situ Polymerization." In CHI '20: CHI Conference on Human Factors in Computing Systems. New York, NY, USA: ACM, 2020. http://dx.doi.org/10.1145/3313831.3376841.
Full textNewmai, M. Boazbou, Abhitosh Kedia, and Pandian Senthil Kumar. "NVP encapsulated gold nanoclusters by in situ polymerization of monomer." In SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4872688.
Full textBaicea, C., A. Ivan, C. Trisca-Rusu, A. C. Nechifor, D. I. Vaireanu, S. I. Voicu, and G. Nechifor. "Ionic conductive silica-polypyrrole composites obtained by in-situ polymerization." In 2010 International Semiconductor Conference (CAS 2010). IEEE, 2010. http://dx.doi.org/10.1109/smicnd.2010.5650655.
Full textWoods, P., K. Schramko, D. Turner, D. Dalrymple, and E. Vinson. "In-Situ Polymerization Controls CO2/Water Channeling at Lick Creek." In SPE Enhanced Oil Recovery Symposium. Society of Petroleum Engineers, 1986. http://dx.doi.org/10.2118/14958-ms.
Full textGao, Chao. "Controlled Functionalization of Carbon Nanotubes by in Situ Polymerization Strategy." In ELECTRIC PROPERTIES OF SYNTHETIC NANOSTRUCTURES: XVII International Winterschool/Euroconference on Electronic Properties of Novel Materials. AIP, 2004. http://dx.doi.org/10.1063/1.1812071.
Full textClarke, Ashley, Alexandros A. Vasileiou, and Marianna Kontopoulou. "Crystalline nanocellulose in biodegradable polyester nanocomposites prepared by in situ polymerization." In PROCEEDINGS OF PPS-32: The 32nd International Conference of the Polymer Processing Society - Conference Papers. Author(s), 2017. http://dx.doi.org/10.1063/1.5016697.
Full textKo, Hung-Han, Yao-Yi Cheng, and Ching-Wei Wang. "Study of surfactant modified MWNT/polyimide composites by in-situ polymerization." In 2013 IEEE International Nanoelectronics Conference (INEC). IEEE, 2013. http://dx.doi.org/10.1109/inec.2013.6466087.
Full textShen, Bo, Yihe Zhang, Li Yu, Fengzhu Lv, and Jiwu Shang. "Preparation of graphene sheets/polyimide nanocomposite films by in-situ polymerization." In Third International Conference on Smart Materials and Nanotechnology in Engineering. SPIE, 2012. http://dx.doi.org/10.1117/12.923059.
Full textReports on the topic "In-situ polymerizations"
Palmese, Giuseppe R. Real-Time In-situ Characterization of Electron-Beam-Induced Bulk Polymerizations. Fort Belvoir, VA: Defense Technical Information Center, September 2005. http://dx.doi.org/10.21236/ada449281.
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