EFFECT OF SPACER LENGTH AND SODIUM CONCENTRATION ON THE REACTIVITY OFPHOTOSENSITIVE COPOLYMERS

Natural rubber-maleic anhydride adducts of different compositions were submitted to ring opening and subsequent esterification reactions wit h oxyalkylcinnamate esters, giving rise to five copolymeric series of different anhydride contents. Differences among the components of each series were given by the size of the hydrocarbon of the lateral chain . From these copolymers, water soluble photosensitive materials have b een obtained as sodium salts, after neutralizing the remaining carboxy lic groups. Kinetic studies were performed by submitting thin films to u.v. radiation. A tentative correlation between the structural dissim ilarities and the dimerization rate constants was investigated.