Synthesis of poly(vinyl ether)s by chain-end capping with a silyl ketene acetal in ab initio cationic polymerisations

Inclusion of a silyl ketene acetal in the non-living cationic polymerisations of methyl and isobutyl vinyl ether provides polymers with ester end groups. The use of an ab initio approach produces materials with high degrees of chain end functionality provided the reaction temperature, monomer concentration and concentration of silyl ketene acetal are optimised. Optimisation, studied mainly by the use of MALDI-ToF mass spectrometry, involved obtaining reaction conditions in which the dominant termination reaction was alkylation of the silyl ketene acetal then rapid desilation produced the ester end groups.