Adsorption of Poly(butyl methacrylate) and Its Mixtures with Polystyrene from Solutions: Adsorption Kinetics and...

Using IR spectroscopy of attenuated total inner reflectance (ATIR) the adsorption kinetics and structure of the adsorption layer of poly(butyl methacrylate) on the Ge surface from solutions in CCl4 of pure polymer and its mixtures with polystyrene have been investigated. It was shown that at the first stage of adsorption of poly(butyl methacrylate) from diluted solution, a layer of high connectivity of macromolecules with Ge surface is formed. The diffusion coefficient of macromolecules on this part of the kinetic curve corresponds to that for the glassy state. With increasing adsorption, the fraction of bonded segments diminishes and macromolecules in the adsorption layer become more mobile. On this part of the kinetic curve there is observed a sharp increase in both the diffusion coefficient of macromolecules and the adsorption rate. On transition from diluted to semidiluted solutions the mechanism of adsorption changes. The coefficient of diffusion of macromolecules coincides with that for reptation movement of macromolecules in the entanglement network. It was shown that introduction of polystyrene into solutions affects the adsorption value and structure of the adsorption layer. This effect is supposed to be connected to possible changes in combinatorial entropy of the system.