Cationic copolymerization of phenyl glycidyl ether with lactones. Characterization of the reaction mixture with chromatographic methods

Abstract

This paper refers to the influence of the catalysts boron trifluoride p-methoxyaniline complex (BF3 · MA) and boron trifluoride etherate complex (BF3 · Et2O) having different reactivity in cationic copolymerization of phenyl glycidyl ether (PGE) with γ-butyrolactone (γ-BL) and ϵ-caprolactone (ϵ-CL), respectively. Reactions were followed by FT-IR, HPLC and SEC. SEC with multiple detection and Two-Dimensional-Chromatography HPLC/SEC were used to characterize the products in view to their copolymer compositions. In the presence of BF3 · MA a preferred formation of spiroorthoesters (SOE) was observed; the polymerization of SOE under these conditions can be neglected. In case of the more reactive BF3 · Et2O the epoxide homopolymerization strongly competes with SOE formation, resulting in a product mixture of epoxide homopolymers (and in the case of ϵ-CL also lactone homopolymers) and copolymers with low lactone content.