UV-induced crosslinking of the biopolyester poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)

Films of the biopolyester poly(3-hydroxybutyrate)- co -(3-hydroxyvalerate) PHB - HV , a microbe-derived poly(hydroxyalkanoate), were crosslinked with 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone BA under UV irradiation. The degree of network formation reached 90% within irradiation times lower than 1 min. The 3 wt% concentration of BA in PHB - HV was found to be the optimum with respect to the rate of crosslinking relative to the rate of chain scission, which were derived from Charlesby-Pinner analyses. The PHB - HV / BA system could successfully be used for the generation of one- and two-step photolithographic imprints with reasonable resolution in the 50 μm range and, hence, proved to be an efficient system for finishing with biopolyesters. UV-induced crosslinking of biodegradable poly(hydroxyalkanoate)s was optimized and used for photolithography, proving to be an efficient system for crosslinking in films.