ESR Studies of the Adsorption Behavior of Styrene–Methyl Methacrylate Copolymer at the Solid–Liquid Interface

The conformation of the copolymer of styrene and spin-labeled methyl methacrylate adsorbed on nonporous silica from solution was investigated by the use of the ESR method. The attached segment fraction of methyl methacrylate, PMMA, in the copolymer was evaluated experimentally. The attached segment fraction of styrene, PST, and the total attached segment fraction, PTOT, in the copolymer were estimated by means of numerical calculations from the value of PMMA. The amounts of saturated adsorption, AS, were obtained as a function of the mole fraction of styrene in the copolymer. The AS values of the copolymers through the mole fractions of styrene of 0.8 increased slightly with the mole fraction of styrene. The AS values of the copolymers at the mole fractions of styrene in excess of 0.8 decreased steeply to that of the styrene homopolymer. The change in the AS values of the copolymers was explicable in terms of the changes in the values of the surface coverage and the values of PTOT. The adsorbed methyl met...