Abstract
Copper(0)-mediated reversible-deactivation radical polymerization(Cu(0)-mediated RDRP)of the water-soluble monomer N-isopropylacrylamide(NIPAM)has been challenging with the problems of high dispersity,poor control over the molecular weights(MWs)or complex or multi reaction steps,etc.In this work,we report the well-controlled polymerization of NIPAM in water via a facile one-pot and one-step Cu(0)-mediated RDRP.The results of this approach show that the key for kicking off the Cu(0)-mediated NIPAM RDRPs is to ensure sufficient CuⅠ at the very beginning,and the key to achieve a well-controlled chain growth is to provide adequate deactivation strength during the polymerization process.For NIPAM,which has a high propagation rate constant,the deactivation control can be effectively enhanced by extra adding deactivator(i.e.,CuⅡ)to the system.Moreover,a low reaction temperature(4 ℃)is necessary in the controlled synthesis of higher MW poly(N-isopropylacrylamide)(PNIPAM)to avoid the compromise in control caused by the phase transition from its lower critical solution temperature(LCST).Through this new kinetically controlled strategy,PNIPAMs with well-defined structure,narrow molecular weight distributions(MWDs)and varied MWs were successfully achieved.
基金项目
Science Foundation Ireland(SFI)Frontiers for the Future call(2019)(19/FFP/6522)
国家自然科学基金(51873179)
Irish Research Council(IRC)Government of Ireland Postdoctoral Fellowship(GOIPD/2022/209)
NETL
NSTL
万方数据