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Showing 1 to 20 of 29 for “"segmented copolymers"”.
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Structure-property relationships in segmented copolymers
The structure-property relationships for various segmented copolymers were investigated. A number of mechanical and thermal characteristics were determined. The morphology was characterized by SAXS with respect to size and dispersion of domains; degree of phase separation and the domain interfacial …
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Synthesis and characterization of polydimethylsiloxane-polyamide segmented copolymers
… is feasible. Polyamide-polydimethylsiloxane segmented or block copolymers were found to be suitable "interfacial" agents. They were synthesized by reacting aminopropyl-terminated polydimethylsiloxane (PDMS) oligomers with sebacyl chloride via an interfacial polymerization in which methylene …
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Synthesis and characterization of polydimethylsiloxane-urea segmented copolymers
… preparation of polydimethylsiloxane-urea (A-B)n segmented or multiblock copolymers has been investigated. These copolymers were synthesized from 4,4¹-diphenylmethane diisocyanate (MDI) and a,ω-bis(aminopropyl)polydimethylsiloxane (PSX) of different molecular weights by solution polymerization. …
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Siloxane modified polyurea and polyurethane urea segmented copolymers
High molecular weight polyether urea copolymers were synthesized using perfectly difunctional aromatic amine terminated polypropylene oxide (PPO) (2800 <Mn>) prepared via aluminum porphorin initiated coordination polymerization. The resulting segmented copolymer showed much higher tensile strength …
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Synthesis of poly(arylene ether sulfone)-polyimide segmented copolymers
… reactions. Poly(arylene ether sulfone)-Polyimide segmented copolymers were synthesized using a solution imidization procedure with NMP as the solvent and o-dichlorobenzene as the azeotroping agent. The polysulfone oligomers were reacted into the system via the diamine oligomer. The segmented …
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Synthesis and Characterization of Cycloaliphatic and Aromatic Polyester/Poly(dimethylsiloxane) Segmented Copolymers
… and aromatic polyester/ poly(dimethylsiloxane) segmented copolymers. The cycloaliphatic copolymers were synthesized via a melt process using a high trans content 1,4 dimethylcyclohexanedicarboxylate, and 1,4 butanediol or cyclohexanedimethanol, while the partially aromatic systems were …
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Synthesis and Properties of Ion-Containing Block and Segmented Copolymers and Their Composites
Ion-containing segmented polyurethanes exhibit unique morphology and physical properties due to synergistic interactions of electrostatic, hydrogen bonding, and hydrophobic interactions. A fundamental investigation on a series of well-defined ion-containing polyurethanes elucidated the influence of …
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Non-covalent Intermolecular Interactions in Polymer Design: Segmented Copolymers to Non-viral Gene Delivery Vectors
… the properties of a given system, from segmented copolymers to interactions of functionalized polymers with non-viral nucleic acids delivery vehicles. The ability to control the intermolecular interactions of a given system allow for tailoring of that system to yield a desired outcome, …
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Synthesis, kinetics and supercritical fluid fractionation studies of functional organosiloxanes and their incorporation into segmented copolymers
The synthesis of organosiloxanes via equilibration processes is fairly well known, but relatively little is known about the detailed kinetics and mechanisms involved, particularly in the presence of functional endblockers. A major focus of the present study was to investigate aspects of the …
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Synthesis and characterization of perfectly alternating segmented copolymers comprised of poly(dimethylsiloxane)s and engineering thermoplastics
Novel perfectly alternating segmented copolymers containing imide junction points were synthesized via terminal amine-anhydride coupling from poly(dimethylsiloxane)s and either poly(arylene ether)s or polyimides. The copolymers were characterized in solution and the solid state. The -(-A-B-)-n …
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Investigation of the Influence of Selected Variables on the Solid State Structure-Property Behavior of Segmented Copolymers
Segmented copolymers are a commercially important class of materials that are utilized in a wide variety of applications. In these systems a relatively large number of variables such as backbone chemistry, segment molecular weight, and the overall molecular weight of the copolymer can be …
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Synthesis and Characterization of Hydrophilic-Hydrophobic Poly (Arylene Ether Sulfone) Random and Segmented Copolymers for Membrane Applications
… and poly(ethylene oxide)-containing random and segmented copolymers for reverse osmosis and gas separation membranes. The second chapter of this dissertation describes synthesis of disulfonated poly(arylene ether sulfone) random copolymers with oligomeric molecular weights that contain …
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Synthesis and characterization of polyether-ester liquid crystalline polyesters and poly(arylene ether ketone)-lcp segmented copolymers
… were found to be useful for synthesizing LCP copolymers and segmented copolymers. A variety of polyarylates based on 5-tertiary butylisophthalic acid were synthesized via melt acidolysis techniques. The resulting high molecular weight polyarylates were amorphous polymers and the t-butyl groups …
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Direct Polymerization Of Sulfonated Poly(arylene ether) Random Copolymers And Poly(imide)Sulfonated Poly(arylene ether) Segmented Copolymers: New Candidates For Proton Exchange Membrane Fuel Cell Material Systems
… weight, film-forming, ductile, ion conducting copolymers. These were converted to the acid form and investigated as proton exchange membranes for fuel cells. Hydrophilicity increased with the level of sulfonation. However, water sorption increased gradually until about 50 mole percent SDCDPS …
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Synthesis and basic characteristics of segmented poly(arylene ether sulfone)-poly(arylate) copolymers
Segmented copolymer systems composed of an amorphous g1assy engineering polymer as one segment and a potentially anisotropic polyester as the second segment were synthesized and investigated. The engineering thermoplastic segment was based on various all aromatic poly(arylene ether sulfooes) …
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Structure–Property Relationships Of: 1) Novel Polyurethane and Polyurea Segmented Copolymers and 2) The Influence of Selected Solution Casting Variables on the Solid State Structure of Synthetic Polypeptide Films Based on Glutamate Chemistry
… dissertation concern the characterization of segmented polyurethanes and polyureas synthesized without the use of chain extenders'molecules that are typically used to promote a microphase separated morphology that gives these materials their useful characteristics. Polyurethanes in which a …
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Synthesis and characterization of novel polyester/polysiloxane and polyester/arylphosphine oxide copolymers
… / cycloaliphatic polyester segmented copolymers were prepared and characterized. Specifically, polyesters based on dimethyl 1,4-cyclohexane dicarboxylate and 1,4-butanediol were employed. The copolymers were synthesized via a melt process using a high trans content isomer …
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Mechanics of elastomeric copolymers
Elastomeric copolymers have been versatile materials for a broad variety of engineering applications of critical importance ranging from ballistic protective coatings to self-healing microstructures, possessing a backbone structure composed of alternate hard and soft segments, where the hard/soft …
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Studies of blends containing liquid crystalline polymers with PET and related investigations of hydroquinone/biphenol polysulfone systems
… Also a study to synthesize and characterize new segmented copolymers that could produce unusual film properties are discussed. The approach involved the synthesis of high Tg (220 C) isotropic poly (aryl ether sulfone) oligomers of varying segment molecular weights. The thermal and mechanical …
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Synthesis and characterization of poly(arylene ethers) and functionalized oligomers
… synthetic techniques to prepare novel block and segmented copolymers were defined. As the molecular weight of the sulfone oligomer was varied, the percent sulfone character in a given polymeric material could be systematically changed. The effect was studied in block copolymers with poly(arnide …
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