Organically modifying and modeling analysis of montmorillonites

Different alkyl-amines(ammoniums) were used to organically modify montmorillonite (MMT), and the influence of modifying time on the intergallery distance of the organically modified MMT(OMM) was analyzed. It showed that the intergallery distance of the OMM has little reliance on the organically modifying time, but depends largely on the kind of alkyl-amines(ammoniums) which were used. When the carbon numbers of the main chains of the alkyl-amines(ammoniums) increase, the intergallery distances of the OMMs increase; when the carbon numbers are the same, the intergallery distance of MMT organically modified by quarternary alkyl-ammonium is bigger than that of MMT organically modified by primary alkyl-ammonium. Secondly, models have been built to analyze the mechanism of the increase of the intergallery distance of the OMM. (C) 2003 Elsevier Science Ltd. All rights reserved.