Photochromism of 4‐acryloxyazobenzene/(−)‐menthyl acrylate copolymers

Abstract

AbstractCopolymers of trans‐4‐acryloxyazobenzene (AAB) with (−)‐menthyl acrylate (MtA) have been prepared by free radical initiation; comonomer reactivity ratios have been found to be rAAB = 0.89 and rMtA = 0.53. Dependence of chiroptical properties on copolymer composition has been investigated and contribution to circular dichroism by azobenzene chromophores of isolated and sequence AAB units, as well as the influence of the trans to cis photoisomerization, have been determined. Kinetics of photoinduced trans → cis and thermally induced cis → trans isomerization of azobenzene side chains have also been examined and the kinetic parameters evaluated with relation to copolymer structure. The results have been discussed in terms of light‐induced secondary structure reversible modifications.