The present invention relates to polymers modified to increase their resorbability. In particular, the polymers of the invention have phenyl ester side chains which are good leaving groups and which thereby increase the resorption rate of the polymer relative to the same polymer, for example, bearing a comparable amount of an alkyl ester side chain. Such polymers are generally water insoluble, but when modified are able to solublize drugs and upon degradation and resorption, release those in a physiological environment in a controlled and/or sustained manner.