Shear induced clay organo‐modification: application to plasticized starch nano‐biocomposites

The present paper reports the successful development of a straightforward clay organo‐modification protocol named “Shear Induced Clay Organo‐modification” process, or SICO. To develop such a fast process, natural montmorillonite has been organo‐modified with cationic starch (surfactant) under shearing. According to the obtained results, this process allows the preparation of a pre‐exfoliated montmorillonite, organo‐modified by cationic starch (OMMT‐CS). Then, the OMMT‐CS has been dispersed into different plasticized starch‐based plastics, varying the polysaccharide botanical source, to obtain nano‐biocomposites displaying an exfoliated morphology. To establish the efficiency of this protocol and highlight this nano‐structuration, uniaxial tensile tests have been performed on these materials. The mechanical properties have been compared with those obtained with nano‐biocomposites elaborated with OMMT‐CS prepared with the conventional and efficient Exfoliation/Adsorption technique. Since comparable properties are obtained, we assume that the SICO process is a powerful technique to easily and quickly organo‐modify the montmorillonite clay and to obtain exfoliated nano‐biocomposites. Copyright © 2009 John Wiley & Sons, Ltd.