Furthermore, the presence of the long alkyl chains in the interlayer space reduces the hydrophilic character of these domains and in addition the host fatty acid alkyl chains are drawn inside the clay interlayer space owing to the strong van der Waals force of attraction. Moreover, the possibility of interaction via hydrogen-bonding between the ammonium head groups of quaternary ammonium compound and the carboxylic acid of various fatty acids could also be speculated.