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Thermoplastic vulcanizate(TPV)/organoclay nanocomposites have been successfully prepared by melt intercalation method. Maleic anhydride modified polypropylene has been used as a compatibilizer. The TPV/organoclay nanocomposites have been characterized by Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Transmission Electron Microscope (TEM). The nanocomposite as evidenced by X-ray diffraction is an intercalated one. The nanocomposites exhibited remarkable improvement in tensile and storage modulus over their pristine counterpart. The dynamic mechanical analysis reveals that the glass transition temperature of the polypropylene phase of the nanocomposite is increased (compared to its pristine counterpart), whereas the EPDM phase remains same. The nanocomposites showed improved solvent resistance over its pristine counterpart. The structure-property correlation of the nanocomposites is attempted.

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The rate of enzymatic degradation of surface‐modified microbial polyesters, poly[(R)‐3‐hydroxybutyrate] and poly[(R)‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate], was studied. The plasma treatments were carried out in a CF3H or O2 environment. It was found that the CF3H plasma‐treated polyesters exhibited significant retardation of enzymatic erosion because of the surface fluorocarbon groups induced by CF3H plasma. These surface fluorocarbon groups act as retardants on enzymatic degradation due to increased hydrophobicity and of the inactivity of enzymes. However, the increased surface hydrophilicity of polyesters induced by O2 plasma results in no significant acceleration of the enzymatic erosion, which may be due to the thin modified layer.