The ultimate goal of this project is to synthesize a novel UV-cross-linkable non-linear optical (NLO) pendant polyimide. The following work is dedicated to the synthesis and exposure optimization of the UV cross-linkable component. Knowing that highly stable NLO properties can be achieved through cross-linked polymer matrices, where polymer chain immobilization leads to unidirectional orientation of NLO-phores in poled polymer resulting in maximized operational lifetime and the complete cross-linking cannot be achieved even after a long irradiation time for a photo-cross-linkable polymer, a chalcone-based UV curable Model Compound was synthesized and exposed to UV light. Optimization was carried out with respect to four factors: (1) UV light wavelength, (2) Solvent for exposure, (3) Solution concentration and (4) Optimum exposure time. For (1)-(3), UV light of 300nm, lower concentrations of solutions and tetrahydrofuran as a solvent were established using LC Mass Spectroscopy, UV-Vis Spectroscopy, FTIR and NMR characterization techniques. For (4), we determined the optimum curing time for maximum polymer chain immobilization, as reflected by Model Compound solution viscosity and mechanical properties of Model Compound-Polyimide blends (1:7 by weight). Tensile and Dynamic Mechanical Analysis (DMA) analysis of blend films agreed with viscosity results that exposure beyond 45 minutes yielded little additional cross-linking in our UV exposure apparatus.
Library of Congress Subject Headings
Polyimides--Synthesis; Nonlinear optics--Materials
Department, Program, or Center
Center for Materials Science and Engineering
Zope, Indraneel, "Blends of UV-cross-linkable model compound and polyimide; Effect of UV exposure on viscosity and mechanical properties" (2011). Thesis. Rochester Institute of Technology. Accessed from
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