Inverse gas chromatographic study of the surface properties of talc impregnated with different acidic and basic polymers

A severe limitation of inverse gas chromatography at infinite dilution (IGC-ID) is that it is mainly sensitive to high-energy sites making it difficult to obtain information about the surface of heterogeneous solids, e.g. the talc. In this paper, it is shown that a progressive impregnation of the talc surface with a suitable polymer can saturate the high-energy sites making the probes access less energetic free sites, specifically the basal surfaces of talc. Here, such impregnations are carried out using a surfactant (cetyltrimethylammonium bromide (CTAB)), different molecular weights polymers (polyethylene glycol (PEG) 2000, 20000, 35 000, and 100000) and polymers with different acidic or basic character (polyethylvinylether (PEVE), polyvinyl chloride (PVC), polymethylvinylketone (PMVK), and polystyrene (PS)). One of the aims of this study is to estimate the ratio of lateral and basal surfaces. (C) 2002 Elsevier Science B.V. All rights reserved.