Rapid photochromic switching in a rigid polymer matrix using living radical polymerization

Abstract

Fast switching of a photochromic dye in a rigid host matrix has been achieved without any modification of electronic nature of the photochromic entity. The method utilizes living radical polymerization (atom transfer radical polymerization (ATRP)) to grow a low glass transition temperature (Tg) poly(n-butyl acrylate) polymer from a spirooxazine core, creating a low-T g environment to cushion the photochromic dye while keeping the bulk matrix rigid. In these systems, decoloration speed of the photochromic (t 1/2) was reduced by 40-75% depending on the molecular weight of the poly(n-butyl acrylate) attached. We have demonstrated with this methodology a controlled tuning of photochromic switchi..