Photoregulated association of N-(2-hydroxypropyl)methacrylamide copolymers with azobenzene-containing side chains

The solution properties of N-(2-hydroxypropyl)methacrylamide copolymers containing photochromic azohenzene side chains were studied by light-scattering methods. While copolymers containing 4.4 and 8.3 mol % azohenzene were water soluble, copolymers with ≥9.3 mol % azobenzene were soluble in water only in the pseudomicellar form. It was found that metastable aggregates prepared by a stepwise increase in copolymer concentration in aqueous solutions readily diisociated in response to UV irradiation