Structural properties of cationic surfactant/pentanol/water systems and their interaction with negatively charged layer silicates

Hexadecyltrimethylammonium bromide/pentanol/water and hexadecylpyridinium c hloride/pentanol/water liquid crystalline systems were investigated. We stu died the influence of water and pentanol on the swelling and theological pr operties of lamellar liquid crystalline systems. We studied the possibility of inserting negatively charged layer silicates in these cationic surfacta nt/pentanol/water systems. Combining the adsorption data from X-ray diffrac tion, the composition of adsorption layer was calculated. After addition of Na-montmorillonite to the liquid crystalline system, the silicate lamellae were built up into the ordered liquid crystalline structure. Therefore, in the case of adsorption from aqueous solution, ordered liquid crystalline s tructure appears in the adsorption space between the silicate layers, and t his structure determines the degree of swelling and the adsorption layer co mposition on the solid silicate surface. (C) 2001 Elsevier Science B.V. All rights reserved.