POLYMER SWELLING .12. COMPARISONS OF THE ADSORPTION PARAMETERS FOR MONOSUBSTITUTED NONLINEAR ALKANES WITH THOSE FOR THE CORRESPONDING LINEAR ALKANES

This paper reports that the adsorption parameter, alpha (i.e., the number of adsorbed molecules per phenyl group of poly-(styrene-co-divinylbenzene at liquid saturation), for a liquid ZCRR'R", where Z is a phenyl, iodo, bromo, or chloro substituent and the R groups are either hydrogen or alkyl, is consistent with the stereoelectronic influence expected on the basis of molecular structure. The test liquids of this study comprised homologous series of the types ZCH3-m(CH3)m, Z(CH2)n(H), and combinations thereof such as ZCH2-m(R)m(CH2)n(H) and Z(CH2)n(CH)3-m(R)m. The values of alpha-observed for the corresponding cyclic liquids that comprise homologous series of the type ZCR(CH2)n, however, are uniformly much higher than expected based solely on the anticipated decrease in steric hindrance owing to cyclization. It was inferred from this observation that the mode of adsorption of the cyclic molecular species may be different from that for a corresponding noncyclic species as discussed in the text.