Montmorillonite–polycation multilayers incorporated in polyacrylamide

A two-stage synthesis has been developed for the first time to obtain montmorillonite–poly(1-methyl-4-vinylpyridinium) multilayers incorporated in polyacrylamide gels. Firstly, hexadecylpyridinium montmorillonite was entrapped in the polyacrylamide gel during polymerization. In the second stage the cationic surfactant was removed and replaced by alkylated poly(4-vinylpyridine). The products in each stage of preparation were characterized by small-angle X-ray scattering (SAXS). SAXS revealed highly ordered multilayers of polycation–montmorillonite particles in the gel. This structure could not be obtained by mixing the solution of the polycation salt with the aqueous dispersion of montmorillonite or with the dispersion entrapped in the gel.