Synthesis of multifunctional poly(D,L-lactide)-poly(oxyethylene)-poly(D,L-lactide) triblock copolymers

Triblock copolymers comprising multifunctional poly(oxyethylene) (PEO) central block with various regularly distributed side functionalities and poly(D,L-lactide) outer blocks were synthesized. In the first step, an acetal-linked, in-chain multifunctional PEO was used as a macroinitiator for the metal-free controlled ring-opening polymerization of D,L-lactide. The amphiphilic biodegradable triblock copolymers provide a platform for further multifunctionalization through efficient quaternization and ‘click’ reactions. Thus, zwitterionic, fluorophilic, alkyne and alkyl pendant functionalities were introduced into the central PEO-block.[graphic not available: see fulltext]