Catalyst-free synthesis of high-molecular weight poly(alkylene oxalate)s†
Abstract
In this work, a catalyst-free protocol, namely “volatility-assisted competitive transesterification polymerization”, was proposed to synthesize poly(alkylene oxalate)s in short reaction times. The polymerization was based on the different nucleophilicities of the terminal hydroxyl groups between half-esterified ethylene glycol and n-alkyl diols, as well as the high volatility of ethylene glycol. Oligo(ethylene oxalate)s and n-alkyl (carbon numbers = 4, 6, 8, 10, 12) diols were used as the raw materials. The high-molecular-weight and light-colored poly(alkylene oxalate)s were obtained in ca. 3 h. The products showed excellent mechanical and thermal properties compared with commercial plastics (LLDPE and PBS), and seawater degradability.