Highly Rapid Preparation of a Bio-modified Nanoclay with Chitosan.

Nanoclays are widely used in preparation of polymer clay nanocomposites. They are mostly prepared through cation exchange reaction between clay and cationic intercalants. Alkyl ammonium salts and alkyl amines are usually used as intercalants for the nanoclay preparation. Due to the toxicity of the intercalants, the current commercial nanoclays are not suitable for bio-applications. In the present report, a biological macromolecule (chitosan) was selected for the clay modification. The obtained bio-modified nanoclay can be used to prepare polymer-clay nanocomposites for various applications in biomedicine. In addition, this report comprises the first successful attempts to use a new approach for rapid preparation of chitosan-intercalated bentonite under green conditions. The conventional time-consuming manner (6-48 h) was replaced with a novel approach to quicken the reaction very considerably. XRD Studies exhibit that the clay galleries were increased from 12.34 to 16.45°A using a combination of ultrasound (30 min)-microwave (3 min)-irradiation.