Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 5 of 5 for “"Isocyanate-free"”.
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Isocyanate-free synthesis of (functional) polyureas, polyurethanes, and urethane-containing copolymers
… and urethane-containing copolymers without using isocyanates or phosgene by step-growth reactions in bulk or solution. An important aspect of this thesis was the use of easily accessible reagents, such as diamines, amino alcohols, diphenyl carbonate, ethylene carbonate, 1,2-propylene carbonate, …
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Siloxane-Based Reinforcement of Polysiloxanes: from Supramolecular Interactions to Nanoparticles
… circumvents the accustomed prerequisite of isocyanate monomer, solvent, and metal catalysts to afford isocyanate-free PDMS polyureas using bio-derived urea with the only reaction byproduct being ammonia, a fundamental raw ingredient for agricultural and industrial products. As professed …
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Bio-inspired Design and Self-Assembly of Nucleobase- and Ion-Containing Polymers
… synthesis of supramolecular polymers using free radical polymerization and controlled radical polymerization techniques. Comprehensive investigations for the structure-property-morphology relationships of these supramolecular polymers elucidated the effect of noncovalent interactions on …
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Novel Monomer Design for Next-Generation Step-Growth Polymers
… zero-shear melt viscosity, average hole-size free volume, and the plateau modulus prior to viscous flow during dynamic mechanical analysis (DMA). The 3,3'-PEI composition interestingly exhibited a ~20 °C higher Tg than the corresponding 4,4'-PEI analog. Moreover, melt rheological analysis …
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Tailoring Siloxane Functionality for Lithography-based 3D Printing
… diamine chain extender and urea afforded isocyanate-free polyureas in the absence of solvent and catalyst. Dynamic mechanical analysis (DMA) measured multiple, distinct α-relaxations that suggested microphase separation. This work leverages the unique properties of PDMS and provides …