Mechanical and thermal properties of waste Abelmoschus manihot fibre-reinforced epoxy composites

In this work, Abelmoschus manihot waste fibre was utilized to fabricate epoxy-based composite; raw, 15% alkali-treated and 130% grafted AMF composites were prepared with 10%, 20% and 30% loadings, and the mechanical properties were evaluated. It was observed that, at 30% loading, 130% grafted composite gave the highest tensile strength of 65.73 MPa and the flexural, impact strength, interlaminar shear strength and microhardness gave 130%, 7.06 J, 67.9 MPa and 64%, respectively. Chemical resistance was also found to be excellent for grafted AMF at 30% loading. Similarly, the DMA analysis indicated an increase in storage and loss modulus with grafted fibre composite and a decrease in Tan delta with 30% loadings. Dimensional stability was excellent with respect to grafted AMF composites. SEM analysis proved superior bonding with grafted AMF composites followed by alkali and raw composites. The vertical burning test took a long time to burn off for the grafted AMF composites at 30% loading. TGA proved to be excellent with higher loading in the case of grafted AMF composite. Void volume decreased with respect to fibre loading and with the help of surface modification using alkali treatment and grafting of the fibres. [GRAPHICS]