A number of styrene and methylmethacrylate copolymers containing different UV stabilizer units (benzophenone, phenylbenzotriazole, and naphthylbenzotriazole) fixed to the polymer backbone were characterized by UV spectroscopy and size exclusion chromatography. UV spectroscopy was found to be suitable for the determination of the copolymer composition and the stability of intramolecular hydrogen bonds, which are important for the performance of UV stabilizer molecules. The highest stability of the intramolecular hydrogen bond was obtained for phenylbenzotriazole containing polymers. Using size exclusion chromatography with refractive index and ultraviolet detection, it was shown that the UV stabilizer units were statistically distributed along the different molar mass fractions. Copyright © 1991 John Wiley & Sons, Inc.