Rapid Photochromic Switching in a Rigid Polymer Matrix Using Living Radical Polymerization

摘要

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 (T_g) 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 switching.Coarse and fine tuning can be achieved by adjusting first the choice of polymer and second the molecular weight of the polymer.