Effect of compatibilisers on mechanical and thermal properties of bentonite filled polypropylene composites

Bentonite filled polypropylene composites were prepared using a Polydrive Thermo Haake, internal mixer at 180 °C and at 50 rpm of rotor speed. Effect of compatibilisers on mechanical, thermal, water absorption and morphological properties of bentonite filled polypropylene composites was investigated. Two types of compatibilisers namely, palm oil fatty acid additive (POFA) and polypropylene grafted-maleic anhydride (PPMAH) have been used in this study. The mixing of the composites improved with the addition of POFA. The impact strength and elongation at break increased with the presence of both compatibilisers whilst, tensile strength and Young's modulus improved only with addition of PPMAH. Morphological investigation using SEM revealed that the improvement in impact strength and elongation at break was due to enhancement of the interfacial adhesion between bentonite and PP. The thermal stability of bentonite filled PP improved with the incorporation of POFA and PPMAH. Less percentage of water absorption has been observed in PP-bentonite system with PPMAH.