Preparation of Sequence-controlled Aliphatic Polysulfones by Group Transfer Radical Polymerization

The integration of sulfur atoms into polymer backbones to synthesize S-containing polymers, such as aliphatic polysulfones, renders many unique properties of the materials. Conventional methods are facing great challenges to achieve sequence-controlled aliphatic polysulfones with high molecular weight (MW), significantly restricting the use of these polymers. We devise a novel approach for the preparation of aliphatic polysulfones via sulfonyl radical-mediated group transfer radical polymerization (GTRP). The polymerization proceeds through a practical SO2-free pathway, producing a series of ABC sequence-defined high-MW polymers (up to 199 kg/mol). DFT calculations are conducted, which support the radical Smiles rearrangement pathway involved in the GTRP process.