Organophilic Nano Clay: A Comprehensive Review

Organophilic nano clay is an important organic-inorganic hybrid derived from intelligent combination of two dissimilar components, viz, clays and organic molecules, at the nanometric and molecular level. The clay component of this hybrid provides a 2-D lamellar structure with interesting surface chemistry, which can be engineered by organic molecules. 2:1 layered clay minerals with high cation exchange capacity, e.g. montmorillonite, possess cation exchange sites on the siloxane surface which can be exchanged with suitable organic molecules. Key aspect of this organic treatment is to swell the interlayer space of the clay mineral up to a certain extent reducing interlayer interaction, to produce nanoplatelet of aluminosilicate materials. Those engineered nanoplatelets are used in various fields of applications, viz, polymer nano clay composite, rheological modifier, thickening and gelling agent in paints and lubricants, in waste water treatment, and also as drug delivery vehicle. Intensive research activity in this complex system is attested by evergrowing number of symposia, books and specialized journals devoted to this subject. This present article is an updated review of organophilic nano clay preparation, characterization and application of the material. Important information available in the protected domain of patent is also included.