Photophysics of polymer-bound 2-(2′-hydroxyphenyl)-2H-benzotriazole photostabilizers

Abstract

A problem associated with the use of 2-(2′-hydroxy-5′-methylphenyl)-2H-benzotriazole (HBT) as a UV photostabilizer in commercially produced polymers is its leaching out of the substrate over a period of time leaving the polymer unprotected. One approach to solving this problem is to bond the stabilizer molecule covalently to the polymer chain. The syntheses of several monomeric derivatives of HBT, which can be homopolymerized or copolymerized with suitable monomers, have been reported. Examples of these are 2-(2′-hydroxy-5′-vinylphenyl)-2H-benzotriazole (2H5V) and 2-(2′-hydroxy-4′-methacryloxyphenyl)-2H-benzotriazole (BDHM) which may be copolymerized with styrene (St) and methylmethacrylate ..