Influence of phenol on polymer adsorption at solid-liquid interfaces
The influence of phenol on adsorption of poly(vinyl acetate) (PVAc) and a poly-(ethylene-vinyl acetate) (EVA) copolymer (28.8% vinyl acetate) on finely divided silica has been studied (24░C). Although phenol adsorbs on silica from trichloroethylene (C2HCl3) and cyclohexane (C6H12) in the absence of polymer, concentrations 0.12 M cause only slight reductions in EVA and PVAc adsorbance. On a molar basis, phenol has less effect on polymer adsorbance than had been observed previously for methanol and cycl˛hexanol. Based on changes in the carbonyl ester bands of PVAc and EVA caused by phenol, it interacts more extensively with both polymers in solution than any additive examined to date. Thus, polymer-additive interactions in solution detected spectroscopically are not necessarily directly related to the effect that the additive has on polymer adsorption. This may be related to the fact that phenol adsorbs simultaneously with EVA from C6H12 in such a manner that a silica surface nearly saturated with adsorbed phenol accommodates substantial quantities of EVA.