Halloysite nanotubes (HNT) as reinforcement for compatibilized blends of polypropylene (PP) and polylactic acid (PLA)

Polymer blends and polyblend nanocomposites are very important for developing new materials in the field of polymer science and technology. Polypropylene (PP)/Polylactic acid (PLA)/ Halloysite nanotube (HNT) nanocomposites can be considered as one among such systems. In order to have more interfacial interaction between the polymer components a compatibilizer, maleic anhydride-graft-polypropylene is also employed. Herein, we report the preparation and characterization of compatibilized polyblend nanocomposites of PP/PLA in the ratio of 80:20 with varying weight percentages of HNT from 0 to 10. The nanocomposites were characterized by Fourier transform infra-red spectroscopy (FTIR), X-ray Diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis, polarized optical microscopy (POM) and transmission electron microscopy (TEM). FTIR results showed the interaction between HNT and PP/PLA blend corresponding to the changes in the absorption peaks corresponding to hydroxyl groups associated with HNT. DSC measurements of the blends and nanocomposites indicated that the crystalline nature of the composites gradually increased up to 6 wt% of HNT. The dispersion of the HNT in the polyblend is elucidated by XRD and microscopic measurements such as POM and TEM. A schematic representation of the polyblend nanocomposites is suggested based on the results achieved from the above measurements and 6 wt% of HNT is considered as the optimum concentration for these types of polymer blends.