Synthesis, characterization, and degradation of poly(ethylene-b-ε-caprolactone) diblock copolymer

Abstract

Poly(ethylene-b-ε-caprolactone) (PE-b-PCL) diblock copolymers were synthesized by ring-opening polymerization (ROP) of ε-caprolactone (CL) with -hydroxyl-ω-methyl polyethylene (PE-OH) as a macroinitiator and ammonium decamolybdate (NH4)8[Mo10O34] as a catalyst. Polymerization was conducted in bulk (130–150°C) with high yield (87–97%). Block copolymers with different compositions were obtained and characterized by 1H and 13C NMR, MALDI-TOF, SAXS, and DSC. End-group analysis by NMR and MALDI-TOF indicates the formation of -hydroxyl-ω-methyl PE-b-PCL. The PE-b-PCL degradation was studied using thermogravimetric analysis (TGA) and alkaline hydrolysis. The PCL block was hydrolyzed by NaOH (4M), without any effect on the PE segment.