首页 | 本学科首页   官方微博 | 高级检索  
     


Synthesis and characterization of copolymaleimides containing 4‐cyanobiphenyl‐based side groups for nonlinear optical applications
Authors:Gangadhara  S. Ponrathnam  C. Noel  D. Reyx  F. Kajzar
Abstract:We report the synthesis of a nematic copolymer, P(CBMS‐co‐M3), prepared by free radical polymerization of an equimolecular mixture of p‐(4‐cyanobiphenyl‐4′‐yloxy)methylstyrene (CBMS) and N‐[3‐(4‐cyanobiphenyl‐4′‐yloxy)propyl]maleimide (M3) and two isotropic alternating copolymers, P(S‐alt‐Mn) (n = 3,6) prepared by chemical modification of poly(styrene‐alt‐maleimide), P(S‐alt‐M), by n‐(4‐cyanobiphenyl‐4′‐yloxy)alkan‐1‐ol. These copolymaleimides were characterized by NMR, DSC, and optical microscopy. Some corona poling experiments were performed and the second harmonic coefficients d31 and d33 were measured. It was shown that one can gain in net polar ordering by starting with a liquid crystalline system. The ratio d33/d31 was much larger than 3, in agreement with the molecular statistical models for electric field poling of liquid crystals. At ambient conditions, changes of d33 and d31 are 15% over 325 days. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 513–524, 1999
Keywords:functionalized copolymaleimides  glass transition temperature  second harmonic generation
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号