Effects of combined alkali treatment and clay nanoparticle infusion on thermo-mechanical response of kenaf/PLA biocomposites

Fibre-reinforced biocomposites have inherently low thermo-mechanical properties and hence require some treatments or modifications during the fabrication process in order to enhance these properties. In this work, a combination of alkalization and nanoparticle infusion was used in enhancing thermo-mechanical properties of kenaf fibre-reinforced polylactic acid biocomposites. The biocomposites were made using sodium hydroxide (NaOH) treated kenaf nonwoven mats and polylactic acid infused with clay nanoparticles. Fabrication of the biocomposites was done using the prepreg method and curing at high temperature. Investigation of the thermo-mechanical properties were performed using a thermogravimetric analyser (TGA) and dynamic mechanical analyser (DMA). Results showed that a combination of alkalization and nanoparticle infusion improves the thermal stability of the biocomposites, loss modulus and damping. However, alkalization and nanoparticle infusion decreased the glass transition temperature of the biocomposites. The study shows that combined treatment of biocomposites with sodium hydroxide and clay nanoparticles significantly improves their performance properties. Therefore, this expands the application capabilities of natural fibre reinforced biocomposites. Best results were obtained by a combination of NaOH treatment and infusion with 5 wt% clay nanoparticles.