A well-defined biodegradable 1,2,3-triazolium-functionalized PEG- b -PCL block copolymer: facile synthesis and its compatibilization for PLA/PCL blends

A novel biodegradable 1,2,3-triazolium-functionalized PEG-b-PCL copolymer (TAPEC) was synthesized by the “click” coupling of methoxypolyethylene glycol azide and α- propargyl-ω-hydroxyl-poly(e- caprolactone), followed by the quaternization of the 1,2,3-triazolemoiety with iodomethane. All the intermediates and TAPEC were characterized by 1H NMR, FT-IR, and gel permeation chromatography(GPC). Taking advantage of the characteristics of ionic liquid and block copolymer, this ion-containing diblock copolymer is expected to be used as a novel compatibilizerin mixed biopolyester for regulating the interface and crystallization behaviors. Hence, the TAPEC was evaluated as a compatibilizerand an interface emulsifier in the blends of polylactic acid(PLA) and poly(e- caprolactone) (PCL). Non-isothermal crystallization experimental results showed that the TAPEC with the higher amount of e- caprolactoneunits induces a plasticization and nucleate effect that increased the crystallization ability of the PLA phase; meanwhile, in the PCL phase, the agminated ionic cluster acting as a nucleating agent significantly increased the crystalline of PCL.