Mechanical and Thermal Behaviour of Rice Bran Green Composite Using RSM and Design of Experiment Techniques

Abstract

The aim of this research is to synthesise a cost-effective biodegradable green composite for various low- and medium-load applications. The tensile and flexural results reveal that the rice bran composition in green composite enhances the stiffness of composite, while strength and hardness decrease. The highest values of tensile strength 27 MPa and flexural strength 25 MPa were obtained for 15/85 treated rice bran composites, while the highest value of young modulus 2958 MPa was obtained for the 35/65 composite combination. The highest value of hardness, i.e., 11 HRF was obtained for 15/85 treated rice bran composite. The water absorption test reveals the hydrophilic nature of rice bran and the hydrophobic nature of PLA. Results also reveal better water-absorbing properties of the green composite due to the surface treatment of rice bran. The lowest density of 1.001 g/cm3 found for the 50/50 composite combination means the addition of rice bran makes the composite light in weight. The thermogravimetric analysis performed on the composite to analyse its thermal behaviour shows that major weight loss occurs approximately in the temperature range of 80–350° Celsius. The response surface methodology (RSM) and design of experiment (DOE) optimization model were developed to find that the optimum condition for maximum weight loss reveals two desirable conditions, i.e., 500° Celsius and 424.85° Celsius. ANOVA analysis reveals that the obtained results are significant.