“…Theoretical work has related the vapor pressure lowering of a stationary phase to the structure of the support in terms of the internal pore volume, the surface area, and the distribution function of the pore radii (377). Improvements in polymeric solid supports have included thermal treatment (74,578) to decrease the number of pores without altering the pore diameter and impregnating the support with tetrafluoroethylenevinylidene copolymer (71). Supina and Rose (64O) compared a number of the Porapaks and Chromosorb porous polymers and report all of the polymers suitable for a wide variety of compounds except the application of Chromosorb 103 to highly polar species.…”