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1
Shingleton, Jason Alan. "Characterisation of peroxide crosslinked polyethylene." Thesis, Loughborough University, 1995. https://dspace.lboro.ac.uk/2134/10832.
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British Gas have been using polyethylene pipe and fittings for gas distribution since 1969. The medium density, and more recently high density polyethylene pipes are produced by a simple and well established extrusion process. Unfortunately the production of fittings, especially large diameter fittings is not so simple. Traditionally pipe fittings are made from either injection moulding or by other fabrication techniques which require subsequent cutting and welding of different parts to produce the finished article. Recently however the methodology has been developed to facilitate the production of fittings by rotational moulding. Incorporated into the new methodology is the ability to produce crosslinked fittings by peroxide inclusion. Crosslinking of the pipe fittings has a major advantage in that it produces a substantial improvement in the mechanical properties of the polymer. Of particular importance is the improvement in stress crack resistance. Stress cracking is presently the primary mode of failure in polyethylene pipelines. Cross linking should help to reduce the susceptibility of the pipeline to failure by this method. The purpose of this project has been to investigate the crosslinking process in two rotational moulding grades of polyethylene. In particular a study has been made of the relationships between various chemical and physical properties, and of how these change upon material modification. A series of compression moulded samples containing increasing levels of peroxide have been produced for both polymers. Characterisation of these samples was undertaken using such techniques as Differential Thermal Analysis, Fourier Transform Infrared Spectroscopy, Gel Permeation Chromatography, Gel Content and Microscopy. The results have shown that as peroxide concentration is increased gel content rises sharply before reaching a maximum value. In contrast to the gel content, the crystallinity of the samples was shown to decrease. Infrared analysis provided the facility to monitor the variation in molecule end group concentration with changing peroxide levels. It was found that increasing the level of peroxide resulted in a decrease in the concentration of terminal vinyl unsaturation in an inverse relationship to gel content results. Subsequent gel permeation chromatography analysis demonstrated that the terminal vinyl groups were being lost in a chain extension mechanism which resulted in an increase in the molecular weight of the samples.
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Ovington, Stephen. "Fusion welding of crosslinked polyethylene." Thesis, University of Sunderland, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297127.
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Mohammed, Tan I. "Properties of silane-crosslinked HDPE." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234047.
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Huang, Keyuan. "Decrosslinking of Crosslinked Polyethylene via Ultrasonically Aided Extrusion." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1428160856.
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Lewucha, Cezary. "Stabilisation and characterisation of peroxide-crosslinked high density polyethylene." Thesis, Aston University, 2012. http://publications.aston.ac.uk/26117/.
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Jenkins, John A. Jr. "ULTRASONIC DECROSSLINKING OF CROSSLINKED POLY (ETHYLENE)." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1177185317.
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Dedic, Mirza [Verfasser], and Volkmar [Akademischer Betreuer] Jansson. "Inflammatorische Potenz verschiedener Crosslinked Polyethylene im Mausmodell / Mirza Dedic ; Betreuer: Volkmar Jansson." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1202011721/34.
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Greenway, Giles R. "The effect of processing conditions on the morphology and electric strength of polyethylene blends." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339954.
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Xie, Wa. "Surface Topography and Aesthetics of Recycled Cross-Linked Polyethylene Wire and Cable Coatings." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc799512/.
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Our research focuses on re-using a waste a material, cross-linked polyethylene abbreviated XLPE, which is a widely used coating for wires. XLPE is strong and has excellent thermal properties due to its chemical structure - what leads to the significance of recycling this valuable polymer. Properties of XLPE include good resistance to heat, resistance to chemical corrosion, and high impact strength. A wire is usually composed of a metal core conductor and polymeric coating layers. One creates a new coating, including little pieces of recycled XLPE in the lower layer adjacent to the wire, and virgin XLPE only in the upper layer. Industries are often wasting materials which might be useful. Mostly, some returned or excess products could be recycled to create a new type of product or enable the original use. This method helps cleaning the waste, lowers the costs, and enhances the income of the manufacturing company. With the changing of the thickness of the outer layer, the roughness changes significantly. Moreover, different processing methods result in surfaces that look differently.
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Van, Wyk Albertus Maritz. "The use of crosslinked polyethylene for the manufacturing of membranes / Albertus Maritz van Wyk." Thesis, Potchefstroom University for Christian Higher Education, 1999. http://hdl.handle.net/10394/9615.
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Increasing environmental awareness over the past decade as well as stringent
environmental laws forced all factories to invest in water treatment processes for
effluent treatment before discharge or re-use. Most of these effluent treatment
processes utilize membranes as the physical. barrier for separation. The membranes
used in water applications are expensive and alternative materials and production
techniques will increase the viability of membrane separation processes.
Experiments conducted on irradiated polyethylene showed that some of its properties
were enhanced while others deteriorated. However, the enhanced properties make
the polyethylene, in particular ultra-high molecular weight polyethylene, an ideal
membrane material. The manufactured membranes were tested in extraction
experiments, and satisfactory results were obtained. Permeation studies on the
membranes compared favourably with similar studies done on commercially
available membranes. An extraction rate of 1.08 g/(m2h) nickel was achieved. A
preliminary cost evaluation showed that these membranes can be manufactured at a
low cost (R13.45/m2). and can be applied as supported liquid membranes. Future
research should focus on methods to decrease the brittleness and stiffness of the
membranes.<br>Thesis (MIng)--PU for CHE, 1999
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Amato, L. "Silane crosslinked polyethylene for pipe applications : characterization and assessment of durability at elevated temperatures." Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/7849.
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Bandaru, Venkata Raghava Sunil Kumar Reddy. "Deformation and Durability Studies of Insulation Polymers." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1227191899.
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Vargas, Marian. "Design of New Polyester Architectures through Copolymerization, Crosslinking, and Diels-Alder Grafting." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5194.
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The compound 2,6-anthracenedicarboxylic acid is used as a comonomer for the synthesis of poly(ethylene terephthalate). The resulting copolymers are characterized and further functionalized by Diels-Alder grafting or crosslinking through the anthracenate unit. Diels-Alder reaction is used to graft small molecules and oligomers endcapped with maleimide as dienophiles on to poly(ethylene terephthalate-co-2,6-anthracenedicarboxylate),PET-co-A. Maleimide-capped poly(ethylene glycol) is grafted onto PET-co-A to improved its hydrophilicity.
2,6-Anthracenedicarboxylic acid is also incorporated into the known liquid crystalline polymer, LCP, poly(4-oxybenzoate-co-1,4-phenylene isophthalate), HIQ40. The resulting copolymer, poly(4-oxybenzoate-co-1,4-phenylene isophthalate-co-2,6-phenylene anthracenate), HIQ40-co-A, shows LCP behavior. These HIQ40-co-A copolymers are grafted with maleimide end-capped monomers and polymers andcrosslinked with bismaleimides through a Diels-Alder mechanism.
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Goetz, Lee Ann. "Preparation and analysis of crosslinked lignocellulosic fibers and cellulose nanowhiskers with poly(methyl-vinyl ether co maleic acid) â " polyethylene glycol to create novel water absorbing materials." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45893.
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The search for cellulosic based products as a viable alternative for petroleum-based products was the impetus for covalently crosslinking lignocellulosic fibers and nanocellulose whiskers with poly(methyl vinyl ether) co maleic acid (PMVEMA) - polyethylene glycol (PEG). The lignocellulosics used were ECF bleached softwood (pine) and ECF bleached birch kraft pulp. This thesis also tests the hypothesis that water absorption and retention can be improved by grafting PMVEMA-PEG to the surface of ECF bleached kraft pulp hardwood and softwood fibers via microwave initiated crosslinking. The crosslinking of the PMVEMA to hardwood and softwood kraft ECF bleached pulp fibers resulted in enhanced water absorbing pulp fibers where the PMVEMA is grafted onto the surface of the fibers. The crosslinking was initiated both thermally and via microwave irradiation and the water absorption and water retention was measured as the percent of grafted PMVEMA. This was the first application of microwave crosslinking of pulp fibers with the goal of creating water absorbing pulp fibers. Ultimately, the water absorption values ranged from 28.70 g water per g dry crosslinked pulp fiber (g/g) to 230.10 g/g and the water retention values ranged from 26% to 71% of the water retained that was absorbed by the crosslinked pulp fibers. The microwave initiated crosslinked fibers had comparable results to the thermally crosslinked fibers with a decreased reaction time, from 6.50 min (thermal) to 1 min 45 sec (microwave).
Cellulose nanowhiskers, crystalline rods of cellulose, have been investigated due to their unique properties, such as nanoscale dimensions, low density, high surface area, mechanical strength, and surface morphology and available surface chemistry. Prior to this study, the crosslinking of cellulose whiskers with the matrix via solution casting of liquid suspensions of whiskers and matrix had not been explored. The hypothesis to be investigated was that incorporating cellulosic whiskers with the PMVEMA-PEG matrix and crosslinking the whiskers with the matrix would yield films that demonstrate unique properties when compared to prior work of crosslinking of PMVEMA-PEG to macroscopic ECF bleached kraft pulp fibers.
Solution cast composites of cellulose nanowhiskers-PMVEMA-PEG were crosslinked at 135 °C for 6.5 min and analyzed for crosslinking, thermal stability, strength and mechanical properties, whisker dispersion, and water absorption and uptake rates. The whisker-composites demonstrated unique properties upon crosslinking the whiskers with PMVEMA-PEG, especially the elongation at break and tensile strength upon conditioning of the final materials at various relative humidities. In addition, the whiskers improved the thermal stability of the PMVEMA-PEG matrix. This is significant as methods of improving processing thermal stability are key to developing new materials that utilize cellulose whiskers, PMVEMA, and PEG. This thesis addresses the hypothesis that cellulose nanowhiskers that are crosslinked with a matrix can create new whisker-matrix composites that behave differently after crosslinking.
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Neitzel, Rüdiger. "Gleitpaarung Highly-Crosslinked Polyethylen(XPE)-Metall." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-98966.
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Rapp, Géraldine. "Analyse multi-échelle du vieillissement thermo-oxydant d’un mélange de polyéthylènes réticulés." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC039/document.
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Les travaux entrepris dans le cadre de cette thèse portent sur l’étude de la représentativité du vieillissement thermique accéléré par rapport au vieillissement en conditions d’usage de mélanges de polyéthylènes utilisés comme isolant de câbles qualifiés K1 de dernière génération dans les bâtiments réacteurs des centrales nucléaires. L’influence de l’état physique des constituants du mélange pendant le vieillissement sur les cinétiques et les mécanismes de vieillissement est également étudiée. Le matériau est un mélange de deux polyéthylènes : un polyéthylène linéaire (PE) et un polyéthylène ramifié (PEcB) réticulé au peroxyde. Une approche basée sur l’analyse multi-échelle (moléculaire, microstructurale, macromoléculaire et macroscopique) a été mise en place. Plusieurs températures de vieillissement ont été choisies afin de faire varier l’état physique de l’un ou des deux polyéthylènes du mélange au cours du vieillissement. Les résultats à l’échelle moléculaire montrent les mêmes produits d’oxydation et les mêmes cinétiques pour le PE et le PEcB. En revanche, on observe une oxydation plus rapide du mélange 5050. Les cinétiques d’oxydation obéissent à une loi d’Arrhenius pour des vieillissements compris entre 80°C et 110°C, mais l’extrapolation à la température d’utilisation (60°C) n’est pas représentative du résultat expérimental. L’état physique (solide ou fondu) des échantillons au moment du vieillissement n’explique pas la non-représentativité des vieillissements accélérés. Les variations des propriétés mécaniques peuvent être reliées à l’évolution de la microstructure de chaque polymère et de leur architecture macromoléculaire au cours du vieillissement thermo-oxydant. Néanmoins, il apparaît difficile de corréler l’évolution de la structure chimique au cours du vieillissement avec l’évolution des propriétés mécaniques. Cette étude souligne l’importance de l’approche multi-échelle pour avoir une compréhension globale des phénomènes de vieillissement<br>This work is devoted to the study of the representativeness of accelerated thermal ageing compared to ageing in use conditions of polyethylene blends used as insulant in the lastest-generation K1 qualified cables in nuclear power plants’ reactor buildings. The influence of the physical state of the components in the blends during ageing on the kinetics and ageing mechanisms is also studied. The material is a blend of two polyethylenes: a linear polyethylene (PE) and a branched polyethylene (PEcB) crosslinked with peroxides. An approach based on the multi-scale analysis (molecular, microstructural, macromolecular and macroscopic) was set up. Several ageing temperatures were chosen in order to vary the physical state of one or both polyethylenes in the blend during ageing. The results at molecular scale show the same oxidation products and kinetics for PE and PEcB. However, one can observe a faster degradation for the 5050 blend. The oxidation kinetics obey the Arrhenius law for thermal ageing between 80°C and 110°C, but extrapolation to the operating temperature (60°C) is not representative of the experimental data. The physical state (solid or molten) of the samples during thermal ageing does not explain the non-representativeness of accelerated ageing. The variations of mechanical properties can be linked to the evolution of the microstructure of each polymer and of their macromolecular architecture during thermo-oxidative ageing. Nevertheless, it is difficult to correlate the evolution of the chemical structure during ageing with the evolution of the mechanical properties. This study emphasizes the importance of the multi-scale analysis in order to have a comprehensive understanding of the ageing phenomena
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Harrasser, Norbert. "Tribologische Untersuchung von crosslinked Polyethylen Inlays im Kniesimulatorversuch." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-116357.
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Nixon, Emily Cummings. "Silanes in sustainable synthesis: applications in polymer grafting, carbon dioxide capture, and gold nanoparticle synthesis." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45847.
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Vinyltrialkoxysilanes are grafted onto polyolefins via a radical mechanism; in a subsequent step, the pendant alkoxysilanes hydrolyze and condense upon exposure to water, resulting formation of crosslinks. Straight chain hydrocarbons were used as model compounds to investigate the regioselectivity of vinyltrimethoxysilane grafting. To stabilize the water-sensitive grafted products, the methoxy groups were substituted using phenyllithium. It was found that this reaction must be carried out for a minimum of three days to ensure full substitution. The grafted products were then separated on a weight basis using semi-preparative HPLC. Analysis of the di-grafted fraction using edited HSQC and HSQC-TOCSY NMR showed that radical propagation occurs via 1,4- and 1,5-intramolecular hydrogen shifts along the hydrocarbon backbone, resulting in multiple grafts per backbone. Post-combustion carbon capture targets CO₂ emissions from large point sources for capture and sequestration. A new class of potential carbon capture agents known as reversible ionic liquids (RevILs) has been synthesized and evaluated in terms of potential performance parameters (e.g. CO₂ capacity, viscosity, enthalpy of regeneration). These RevILs are silylated amines, which react with CO₂ to form a salt comprising an ammonium cation and a carbamate anion that is liquid at room temperature. Structural modifications of the basic silylamine skeleton result in drastic differences in the performance of the resulting RevIL. Systematic variation of the silylated amines allowed determination of a structure-property relationship, and continued iterations will allow development of an ideal candidate for scale-up. The properties and potential applications of gold nanoparticles (AuNP) are highly dependent on their size and shape. These properties are commonly controlled during liquid-phase synthesis through the use of capping agents, which must be removed following synthesis. Reverse micelles can also be used to control the morphology of AuNP during their synthesis. When RevILs are used in the formation of these reverse micelles, either as the disperse phase or as the surfactant, the built-in switch can be used to release the nanoparticles following their synthesis. This release on command could decrease the post-synthetic steps required to clean and purify AuNP prior to use. We have successfully synthesized AuNP using a number of different RevILs.
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Sirimamilla, Pavana Abhiram. "MECHANISTIC STUDY OF CRACK INITIATION AND PROPAGATION IN CROSSLINKED ULTRA HIGH MOLECULAR WEIGHT POLYETHYLENES (UHMWPE) SUBJECTED TO STATIC AND CYCLIC LOADING." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1345862222.
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Dufour, Denis. "Technique d'assemblage de deux pieces en polyethylene : modelisation d'un processus de soudage par reticulation du plan de joint." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13090.
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On assemble par fusion (electrosoudage) et reticulation (soudage chimique) a l'interface grace a la diffusion et la reaction d'un agent reticulant present unitialement dans l'une des deux pieces. Simulation du processus
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Moraes, Lorena Rodrigues da Costa. "Processos de formação de ligações cruzadas de polietileno de alto peso molecular." Universidade do Estado do Rio de Janeiro, 2015. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=8491.
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No projeto desenvolvido, ligações cruzadas foram formadas no polietileno de alta densidade e alto peso molecular, grade HS5103, através dos processos reticulação por peróxidos e silanos, com o objetivo de se avaliar o efeito da introdução de ligações cruzadas nas propriedades térmicas e mecânicas deste PEAD. Misturas entre o HS5103 e os peróxidos orgânicos, 2,5-Dimetil-2,5-di(terc-butilperoxi)hexano (DHBP) e peróxido de dicumila (DCP), foram produzidas e analisadas para a avaliação do efeito dos tipos de peróxido na reticulação e propriedades do PEAD e para determinação da concentração e do tipo de peróxido a ser utilizado como agente iniciador de reticulação por silano. Ensaios de índice de fluidez (MFI), reometria capilar, extração de polímero por xileno (teor de gel), análise termogravimétrica (TGA), calorimetria diferencial de varredura (DSC) e tração foram realizados para caracterização das misturas com peróxidos. Os resultados indicaram aumento da viscosidade com o aumento da concentração de peróxido, sendo o DHBP o que apresentou maior índice de aumento; não houve mudanças relevantes nas propriedades mecânicas e, ocorreu aumento do grau de cristalinidade, sendo mais significativo nas amostras com DCP. Após avaliação dos resultados citados, para as amostras a serem reticuladas via silano, foi promovida a graftização de diferentes concentrações de viniltrimetóxisilano (VTMS) na presença de 0,01%p/p de DCP com a adição de 0,05%p/p de catalisador, posteriormente a reticulação foi promovida em água. As amostras produzidas foram caracterizadas por ensaios de teor de gel, análise dinâmico-mecânica (DMA), espectroscopia de absorção no infravermelho (FTIR), TGA, ensaios de desgaste por deslizamento e tração. Nas amostras com silano a formação de ligações cruzadas foi gradativa, apresentando de 8% de gel para amostra com 0,5%p/p de VTMS a 57 % para amostra com1,5% p/p de silano, maior concentração utilizada. A análise dinâmico-mecânica (DMA) realizada evidenciou que houve um aumento densidade de ligações cruzadas e do módulo de armazenamento após temperatura de fusão com o teor de silano, concordando com os resultados de teor de gel. As análises de FTIR mostraram que houve a graftização e a formação de ligações cruzadas no PEAD HS5103. Não se observou um aumento significativo para o limite de resistência para o PEAD modificado. E os testes de desgaste por deslizamento indicaram um aumento da resistência ao desgaste das amostras reagidas com VTMS.<br>In the project carried out, crosslinks were formed in high density and high molecular weight polyethylene, grade HS5103, through peroxide and silane reticulation processes, aiming to evaluate the effects of the introduction of crosslinks in thermal and mechanical properties of this PEAD. Mixtures between HS103 and organic peroxides, 2,5-Bis(t-butylperoxy)-2,5-dimethylhexane (DHBP) and dicumyl peroxide (DCP) have been produced and analyzed for the evaluation of the effect of types of peroxide in reticulation and PEAD properties and to determine both concentration and type of the peroxide to be used as silane reticulation initiation agent. Melt flow index (MFI), capillary rheometry, xylem polymer extraction (gel content), thermogravimetric analysis (TGA), differential canning calorimetry (DSC) and traction tests were carried out for peroxide mixtures characterization. The results indicated increase of viscosity with the increase of the concentration of peroxide, being DHBP the one with the highest increase level; there have been no relevant changes concerning mechanical properties and there has been an increase in the crystallinity levels, mostly in DCP samples. After the assessment of the former results, for the samples to be reticulated through silane, graphitization of different concentrations of Vinyltrimethoxysilane (VTMS) was carried out, together with 0.01%p/p of DCP, adding 0.05%p/p of a catalyst; later, reticulation was carried out in water. The samples produced were characterized by gel content tests, dynamic-mechanical analysis (DMA), Fourier transform infrared spectroscopy (FTIR), TGA, sliding and traction wear tests. In the silane samples, formation of crosslinks was gradual, showing 8% of gel to the sample with com 0.5%p/p of VTMS to 57 % to the sample with 1.5% p/p of silane, the highest concentration used. The dynamic-mechanical analysis (DMA) showed an increase of density in crosslinks and storing mode after fusion temperature with silane content, converging with gel content results. FTIR analysis showed there has been graphitization and crosslink formations in PEAD HS5103. A significant increase has not been observed concerning the limit of resistance for the modified PEAD. Besides, sliding wear tests indicated an increase of resistance to the wear of samples reacted to VTMS.
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Ku-Yen, Lin, and 林谷彥. "Studying of recycling and utilizing scrap crosslinked polyethylene." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/47670088437125258587.
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碩士<br>崑山科技大學<br>材料工程研究所<br>101<br>In this research, a series of composites were made based on UHMWPE, PP-g-MA and PE-g-MA by recycling and utilizing scrap (Crosslinked Polyethylene，CPE) as addition materials after being mixed in mixing rolls with double screws. The related nature of the composites will be discussed by detecting and analyzing FT-IR, X-ray, SEM, TGA and DMA. The results show as follows:
The composites made of CPE together with UHMWPE，PP-g-MA or PE-g-MA can effectively improve its heat-resisting property. The addition of CPE brings no obvious enhancement to the mechanical property of CPE/PP-g-MA composites, yet the addition of CPE brings improvement to the storage modulus of CPE/UHMWPE composites. What’s more, when CPE is 1%, the storage modulus reaches its maximum, yet the storage modulus of CPE/PE-g-MA composites increases along with the increase of CPE concentration.
Second mixture of CPE/PE-g-MA composites will be helpful to the improvement of its heat-resistance, yet too many crosslinks will worsen its mechanical property and heat-resistance.
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何志成. "The moisture-crosslinked polyethylene and measurment of physical properties." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/29055440506375021086.
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Luitel, Mahesh. "Statistical approach for predicting remaining life of crosslinked polyethylene insulated cables." Thesis, 2005. http://hdl.handle.net/10057/772.
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This study focuses on developing new remaining life model of the Cross linked polyethylene (XLPE) insulated medium voltage cables that are in use for hot and dry climate. Cross linked polyethylene insulating material degrades under the service condition acted upon by thermal and electrical stresses. Degradation of the materials is quantified by two main parameters Fourier Transform Infrared (FTIR) value and strength to withstand the electrical breakdown voltage. These parametric changes obtained by accelerated aging procedure developed with the help of Arrhenius Equation are tested for significance with that found in field aged cable with the help of statistical tools. Anderson-darling test for normality, Analysis of Variance (ANOVA), and one and two sample t-test were used to validate the lab aging procedure with field aging. New aging model, based on two parameters, Fourier Transform Infra Red (FTIR) spectrum value and Electric Breakdown voltage (EBV), was developed to quantify the current equivalent age of the cable and hence remaining life of the cable. The model is validated for different field aged cables in this study.<br>Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering.<br>"December 2005."
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Luitel, Mahesh Jewell Ward T. "Statistical approach for predicting remaining life of crosslinked polyethylene insulated cables." Diss., 2005. http://il.proquest.com/products_umi/dissertations.
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Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical and Computer Engineering.<br>"December 2005." Title from PDF title page (viewed on April 22, 2007). Thesis adviser: Ward T. Jewell. UMI Number: AAT 1436567 Includes bibliographic references (leaves 51-54).
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Chuang, Chih-Kuang, and 莊志光. "Low density polyethylene/ethylene-propylene rubber blends foam crosslinked by electron beam." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/90188846277831469903.
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碩士<br>元智大學<br>化學工程與材料科學學系<br>94<br>LDPE (Low density polyethylene) has a simple chemical structure. It could be recycled and regenerated easily, most of its combustion products are carbon dioxide and water. This study, LDPE was blended with EPR (ethylene-propylene rubber) and irradiated by electron beam under heat to make foam materials. The mixing of amorphous rubber into LDPE resulted LDPE, a semi-crystal material, to have better resiliency. Seven LDPE/EPR blends with different EPR contents ranging from 0 to 100 weight percent were foamed. The microcellular morphology of the foam was investigated using a scanning electron microscope. The effects of decomposition promoter on chemical blowing agent were measured via thermo-gravimetric analysis. The density, tensile strength, elongation at break, compressive strength and compression set of foam were according to the ASTM D-3575 procedures. The LDPE/EPR blend with a weight ratio of 70/30 and a gel fraction ranging from 30% to 50% was found to be an optimum condition for making foam materials.
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Harrasser, Norbert [Verfasser]. "Tribologische Untersuchung von crosslinked Polyethylen-Inlays im Kniesimulatorversuch / vorgelegt von Norbert Harrasser." 2010. http://d-nb.info/1004441215/34.
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Neitzel, Rüdiger [Verfasser]. "Gleitpaarung highly-crosslinked Polyethylen(XPE)-Metall : eine prospektive Nachuntersuchung an 36 Patienten mit Hüfttotalendoprothese / vorgelegt von Rüdiger Neitzel." 2008. http://d-nb.info/993549837/34.
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Hyslop, David. "Delayed-onset Polymer Cross-linking using Functional Nitroxyls." Thesis, 2012. http://hdl.handle.net/1974/7275.
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New polymer cure chemistry is described, wherein the onset of free radical cross-linking is delayed without compromising cure yields. The addition of an acrylate-functionalized nitroxyl, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl (AOTEMPO), to a peroxide-cure formulation quenches free radical activity during the initial stages of the cross-linking process, trapping alkyl radicals as alkoxyamines that bear acrylate functionality. Polymer cross-linking by macro-radical combination is suppressed until all nitroxyl is consumed, at which point radical oligomerization of polymer-bound acrylate groups generates the desired covalent network. As a result, cross-link density losses incurred during radical trapping are recovered during the oligomerization phase of the process. The effectiveness of this approach is demonstrated for a range of polymers, peroxide initiators, reaction temperatures and reagent loadings. Furthermore, AOTEMPO formulations are compared directly to other delayed-onset additives that are used in commercial practice.<br>Thesis (Master, Chemical Engineering) -- Queen's University, 2012-06-11 10:09:20.848