ATR IR spectra and structure of boundary layers of atactic polystyrene

The ATR IR spectra of solutions of atactic polystyrene in chloroform at the boundary with KRS-5 glass in the ranges 2800?C3100 and 1550?C1650cm^?1 are studied. It is shown that the parameters of orientation ?? and polarizability anisotropy ???? _p ? ???? _s of macromolecules estimated from the absorption and refractive indexes and the average complex polarizability of polystyrene boundary layers on KRS-5 vary in an extremum manner with the concentration of polystyrene in a solution. For dilute polystyrene solutions, a high degree of orientation of chains adsorbed on the glass surface is found. The inversion of the sign of polarizability anisotropy ???? _p ? ???? _s and an increase in orientation parameter ?? of macromolecules in boundary layers on KRS-5 are associated with the compression and interpenetration of coils during the transition from semidilute to concentrated solutions of polystyrene.