Initiation Mechanism of the Copolymerization of 1,3,5-Trioxane and Ethylene Oxide

Abstract

Initially, the initiation mechanism for the copolymerization of 1,3,5-trioxane (TO) and ethylene oxide proposed the formation of 1,3-dioxolane from the reaction of ethylene oxide with formaldehyde, and this mechanism was believed plausible for a long time. Recently, we carefully studied the bulk copolymerization of TO and ethylene oxide using boron trifluoride-dibutyl ether as the initiator. Two novel cyclic formals, 1,3,5,7-tetraoxacyclononane (TOCN) and 1,3,5,7,-10-pentaoxacyclododecane (POCD), from the initiation reaction of the copolymerization of TO and ethylene oxide were isolated and identified. From this discovery, we proposed a new initiation mechanism for the copolymerization of TO and ethylene oxide. Ethylene oxide reacts directly with TO to form TOCN and POCD. From TOCN, 1,3,5-trioxepane (TOXP) is formed, and from TOXP, 1,3-dioxolane is formed.