Cationic copolymerization behavior of glycidyl phenyl ether with seven-membered cyclic carbonate

To clarify the cationic copolymerization behavior of epoxide and cyclic carbonate, the copolymerization behavior of glycidyl phenyl ether (GPE) with seven-membered cyclic carbonate (7CC) was carried out using methyl trifluoromethanesulfonate (MeOTf) as a cationic initiator. The addition of 7CC accelerated the consumption rate of GPE, and the resulting copolymers were richer in 7CC-derived unit compared to the feed ration of 7CC. During the copolymerization, a large amount of five-membered cyclic carbonate having a phenoxymethyl group (PM-5CC) was produced as a by-product, which suggests the corresponding spiroorthocarbonate was formed as an intermediate and that residual oxytetramethylene (OTM) unit was incorporated into the copolymer sequence. From H-1 NMR analysis, it was found that the copolymers had a statistically random sequence consisting of GPE, 7CC, and OTM units.