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Polymer and Organic Materials Commons™
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Full-Text Articles in Polymer and Organic Materials
Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson
Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson
Mechanical Engineering Theses
Blood-contacting cardiovascular stents often induce a secondary clotting event due to unrestricted enzymatic activities. The use of hemocompatible polyurethane coatings on these implantable devices is one of the most promising methods to reduce device rejection. In this study, four commercial polyurethane films of various thicknesses and compositions were evaluated for their anticoagulation properties. Results suggested that these films exhibited excellent thermal and physico-mechanical properties while capable of increasing contact time with blood plasma by over a thousand-fold as compared to a control surface. Due to the unknown structure and composition of these commercial films, polyurethane samples were synthesized from toluene …
Tailoring Photodegradation Rates Of Acetal-Containing Polymer Networks, Michael Sandoz
Tailoring Photodegradation Rates Of Acetal-Containing Polymer Networks, Michael Sandoz
Honors Theses
In this thesis, we explore the degradation of poly (thioether acetal) thermosets via a photoinduced thiol-catalyzed ß-scission of acetal linkages incorporated as network crosslink junctions. Specifically, a library of bis-allyl acetal-containing monomers derived from para-substituted benzaldehydes was synthesized and formulated into photopolymerizable thiol-ene resins with commercially available thiol monomers. By varying the electron donating or withdrawing nature of the monomer substituent, we explored the impact of substituent effects on the rate of polymer degradation. Furthermore, we compare the results to those expected from a classical Hammett-type relationship of substituent electronic effects. FTIR was employed to track the appearance of the …
Surface Driven Flows : Liquid Bridges, Drops And Marangoni Propulsion, Samrat Sur
Surface Driven Flows : Liquid Bridges, Drops And Marangoni Propulsion, Samrat Sur
Doctoral Dissertations
Molecules sitting at a free liquid surface against vacuum or gas have weaker binding than molecules in the bulk. The missing (negative) binding energy can therefore be viewed as a positive energy added to the surface itself. Since a larger area of the surface contains larger surface energy, external forces must perform positive work against internal surface forces to increase the total area of the surface. Mathematically, the internal surface forces are represented by surface tension, defined as the normal force per unit of length. One common manifestation of surface tension is the difference in pressure it causes across a …