Preparation of PDMS STEM gels through oxygen tolerance nitroxide mediated polymerization

The postsynthesis polymeric modifications by grafting from the active sites were the primary focus of the structurally tailored and engineered macromolecular (STEM) gels. Therefore, Reversible-deactivation radical polymerization (RDRP) techniques have been employed to more precisely tailor and tune STEM gels. In contrast to atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain transfer polymerization (RAFT), nitroxide-mediated polymerization (NMP) is known to have the advantages of simple components and pure products. Here we report the preparation of polydimethylsiloxane (PDMS) composite gel networks through oxygen tolerance NMP process, with tert-Butyl acrylate (tBA) and fluorinated monomer 2-(Perfluorooctyl)ethyl methacrylate (FMA) as functional comonomers. Compared with conventional radical polymerization (FRP) method, composite gels prepared through NMP method showed higher swelling rate and elongation at break, which proved that the network structure formed by NMP was more uniform. In addition to better thermal stability and toughness, the dormant polymer chain could be reactivated and lead to the “living” post-modification of PDMS gel matrix.