Poly(propylene ether carbonate)-Based Di- and Tri-Block Copolymers: Synthesis and Chromatographic Characterization

Abstract

In this study, ring-opening polymerization (ROP) of propylene carbonate (PC) is conducted for synthesis of novel amphiphilic di- and tri-block copolymers containing poly(ethylene oxide) as hydrophilic with poly(propylene ether-carbonate (PPEC) as a hydrophobic block. A series of di- and tri-block copolymers is synthesized, by using macro-initiators [polyethylene glycol monomethyl ethers and poly(ethylene glycol)s] of different molar masses, while systematically varying monomer to macro-initiator ratio. The synthesized block copolymers are characterized by size exclusion chromatography, for augmentation in the molar mass, NMR for average chemical composition while liquid chromatography at critical conditions, is used for comparison of individual block lengths alongside purity of block copolymers, with regard to presence of homopolymers of both types. Chromatographic critical conditions of the polymer synthesized by ROP of PC, PPEC, are reported for the first time. Established chromatographic critical conditions of PEG and PPEC, successfully tracked presence of homopolymers of both types, with fair comparison of individual block lengths of the block copolymers synthesized by the same macro-initiator.