Layered nanocomposites of expandable clay (montmorillonite,M) and amino acids were prepared by an intercalation reaction in an aqueous solution. L-valine(V), L-threonine(T), L-glutamic acid(G), L-lysine(L), L-histidine(H) and L-arginine(A) were used as amino acid molecules. In the intercalation reaction, the solution pH played an important role in preparing the intercalation compounds; a pH of the solution below 4 was favorable to obtain intercalative layered nanocomposites due to the zwitterionic nature of amino acid molecules. Moreover, the basic side chain of amino acids had a crucial role in determining the structural stability of the layered nanocomposites; the basic amino acid such as L-arginine, L-lysine and L-histidine with basic side chain formed stable intercalated structures, while the other a-amino acids formed only transitory intercalative complexes, which were easily decomposed during the washing process.

Keywords: intercalation; nanocomposite; clay; amino acid