Radical Homopolymerization of Arylsulfonylated α-Olefins to Synthesize Polysulfones - a "SO₂-free" Approach

Traditionally, α-olefins have been regarded as non-homopolymerizable substrates in textbook examples. However, they have the ability to copolymerize with sulfur dioxide, leading to the creation of alternating copolymers. These commodity poly(olefin sulfone)s exhibit a wide array of applications. Nevertheless, the synthesis process involving sulfur dioxide pose considerable hazards and practical difficulties. In this study, we report on the "SO₂-free" radical homopolymerization of sulfonyl α-olefin monomers, resulting in the production of ABC sequence-controlled poly(vinylbenzothiazole-olefin-sulfone)s. This unique radical polymerization process is enhanced by 1,4/1,5-aryl migration, facilitated by the sulfonyl radicals involved in propagation. This demonstrated aryl group migration radical polymerization opens up new possibilities for synthesizing polysulfones with unprecedented main chain sequences and structures, which hold great promise as candidates for innovative polymeric materials.