Visible light-induced atom transfer radical polymerization

摘要

Visible light-induced reverse and simultaneous reverse and normal initiation (SRNI) atom transfer radical polymerizations of vinyl monomers are examined using various dyes and type I photoinitiators. The effect of photoinitiator types on the control of molecular weight and distribution is described. In both dye and type I photoinitiator sensitized SRNI ATRP systems, the molecular weights increase linearly with conversion. However, the experimental molecular weights are considerably higher than the theoretical values and the polymers show broad-molecular-weight distributions ranging from 1.28 to 1.60 in the dye-sensitized SRNI ATRP. However, the polymers obtained by SRNI ATRP using type I photoinitiator system had molecular weight values close to the theoretical ones and very narrow-molecular-weight distributions ranging from 1.11-1.18. Visible light-induced reverse and simultaneous reverse and normal initiation (SRNI) atom transfer radical polymerizations of vinyl monomers, methyl meth(acrylate)s, and styrene are examined by using various dyes and type I photoinitiators. The polymerizations proceed in a well-controlled manner under visible light at room temperature as evidenced by kinetic studies.