Synthesis of a new photoreactive polyester by addition reaction of bisepoxide with f-truxiloyl chloride and chemical modification of this polymer

Abstract

A new reactive polyester (P-I) containing a cyclobutane ring in the main chain and a pendant chloromethyl group in the side chain was synthesized successfully by the addition reaction of diglycidyl ether of bisphenol A (DGEBA) with fi-truxiloyl chloride (TC). The addition reaction of DGEBA with TC proceeded smoothly to give P-1 with a relatively high molecular weight using quaternary onium salts or a crown ether complex as catalysts at 90-C for 15 h. However, the reaction did not occur without a catalyst. Substitution reactions of the obtained P-I with (4-dimethy Iamino)cinnamic acid (MACA), [(4-dimethylamino)-a-cyano]cinnamic acid (MACCA) and (4-dimethylamino4'-hydroxy)chalcone (MACH) were carried out to synthesize certain new multifunctiqnal photosensitive polymers with positive-working groups in the main chain and negative-working groups in the side chains. The reaction of P-I with MACA proceeded very smoothly with 99% conversion to form the corresponding polymer (P-2a) using 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) as a base in DMF. The reaction with MACCA gave the corresponding polymer (P-2b) containing a pendant [(4-dimethylamino)-a-cyano]cinnamJc ester moiety with 26% conversion. The reaction with MIACH produced the corresponding polymer (P-2c) containing a pendant (4-dimethy]amino)chalcone ether moiety with 32% conversion. Photochernical reaction of the thus-obtained P-2a-c was also performed in the film state.