THE EFFECT OF THERMAL HISTORY ON THE SURF ACE-ENERGY CHARACTERISTICS OF POLYSTYRENE

The surface energy was estimated for PS samples prepared from solution s and melts under various quenching and annealing regimes. When polyme r melts were cooled at high cooling rates (v > 50 K/s), the surface en ergy characteristics of PS samples were shown to be identical to those of polymer melt. At v < 50 K/min, all samples were characterized by q uite similar values of surface energy, which were close to those of th e test samples at temperatures near the glass transition temperature. The samples prepared from solutions were characterized by anomalously low values of surface energy. Coefficients of the McLeod equation rela ting the surface energy of PS to the density of polymer were estimated . Surface energy characteristics may be invoked to estimate solubility parameters for polymers.