Preliminary Study on Application of Bentonite as a Filler in Polypropylene Composites

Abstract

The effect of filler loading on mechanical, thermal, water absorption, and morphological properties of bentonite-filled polypropylene has been studied. Polypropylene composites of different filler loading were compounded by using a Polydrive Thermo Haake with Rheomix R600. The temperature and the rotor speed used were 180°C and 50 rpm, respectively. The mixing torque recorded increases with increasing filler loading. It also was found that the value of the tensile strength, impact strength, and elongation at break decreases with increasing filler loading. Contrast increments in flexural and tensile modulus were observed as loading of bentonite increases. Morphological investigation by using scanning electron microscopy revealed that the reduction in tensile strength, impact strength, and elongation at break were due to agglomeration of bentonite particle, particularly for composite with high bentonite loading. The thermal properties were investigated by using thermogravimetric analysis. Thermogravimetric analysis showed decreasing degradation temperatures of composites with increasing bentonite loading. On the other hand, the percentage of water absorption showed an increase with increasing filler loading.

Keywords:

• Bentonite
• Polypropylene
• Mechanical properties
• Thermal properties
• Water absorption