The positive effect of water on photo-induced step transfer-addition & radical-termination (START) polymerization

Abstract

Step-growth radical copolymerization between α,ω-diiodoperfluoroalkanes (A) and α,ω-unconjugated dienes (B) proceeds efficiently through a photo-induced Step Transfer-Addition & Radical-Termination (START) strategy in aqueous/organic biphasic system. The addition of water in our polymerization strategy enhanced the overall polymerization efficiency and inhibited the function loss (C–I) significantly, which has been illustrated through UV-vis tests. Therefore, most of the functional groups (C–I) in the polymer chain end have been preserved in the final polymer product (AB)_n based on ¹⁹F NMR analysis. After polymerization, we could erase the iodine atoms in the main chain of (AB)_n, which generates semifluorinated polyolefins with enhanced thermal stability.