Functional PEG building blocks via copolymerization of ethylene carbonate and tert-butyl glycidyl ether

Abstract

Anionic ring opening copolymerization of ethylene carbonate (EC) and tert-butyl glycidyl ether (TBGE) with CsOH as an initiator using a mono-mode microwave reactor results in poly(EO-co-TBGE) hydroxy telechelic copolymers with M_n(SEC) values between 750 and 1700 g mol⁻¹ and dispersity indices in the range of Đ = 1.05–1.10. The reaction sequence for the formation of narrowly distributed copolymers was investigated by kinetic studies using size exclusion chromatography, ¹H NMR and MALDI-ToF as analytical tools. Transcarbonylation, transalkylation and carbonate fragmentation were identified as fundamental reactions for the formation of carbonate free products with multi block microstructures. ¹³C NMR analysis allowed the determination of monomer sequences within the polymer chain, which confirmed its multi block type structure; different microstructures were obtained by varying the reaction time and monomer composition.