报告题目：New Dendritic and Knot/cyclized polymers from Controlled Multivinyl Monomer Polymerisation and Their Biomedical Applications
报告人：Prof. Wang Wenxin, Charles Institute of Dermatology, School of Medicine, University College Dublin, Ireland
Classical theory has long claimed that the polymerizations of multi-vinyl monomers (MVM) lead to insoluble cross-linked materials, as defined by P. Flory and W. Stockmayer 70 years ago (F-S theory)1, and has since been numerously observed experimentally. Therefore, the (homo)polymerization of MVMs is still considered as a formidable task in chain growth polymerization. In recent decades, the introduction of controlled/living radical polymerizations (CRP) including atom transfer radical polymerization (ATRP) and reversible addition fragmentation chain transfer (RAFT) etc., has led to a significant advance in both synthetic polymer chemistry and physics. We have developed different strategies that allow facile syntheses of unprecedented 3D structured multifunctional materials from commercial available multi-vinyl monomers (MVMs). The syntheses by deactivation enhanced controlled/living radical polymerization can build the MVMs up into either ‘Single Cyclized’ polymer structures2 via linear/cyclization growth strategy, or via ‘vinyl oligomer combination’ strategy to yield veritable hyperbranched polymers3, 4 .
Our breakthrough lies in the ability to alter the growth manner of polymerization by controlling the kinetic chain length together with manipulating chain growth conditions to achieve two clearly different polymer structures. The first is a single chain which is linked repeatedly to create a dense but soluble interlaced knot structure and the second is a combination of short chains to create a veritable dendritic structure which possesses a highly branched structure. The new polymeric materials created from MVMs have demonstrated the great potentials in biomedical applications such as gene delivery vector and injectable scaffold.