Synthesis and photochromic behavior of comb-like acrylate polymer nanoparticle containing spiropyran

Spiropyran (SP) materials have attracted considerable interest owing to sensitive and efficient photochromic properties, but it is a challenge to obtain photochromic materials with excellent sensitive UV-responsivity and photodegradation resistance durability. In this study, a series of comb-like acrylate polymer nanoparticle latexes containing SP are fabricated via miniemulsion polymerization. The influence of the length of the alkyl side chain of comb-like acrylate polymer on some photochromic properties of SP is investigated. Compared with the shortside chain poly(butyl acrylate) (PBA) nanoparticles latexes, the comb-like acrylate polymer nanoparticle latexes with longer side chain possess better photoresponsivity and more excellent photodegradation resistance because the strong interaction and chain flexibility of comb-like alkyl side chain provide effective spaces for the SP-*MC or MC-*SP photochemical isomerization. The investigations of photochromic nanoparticle latexes guide an approach to reversible optical data storage, multipurpose photo-responsive sensing system and show promising application in the field of ultraviolet intensity indicator and flexible wearable UV protective clothing.