Effect of spent coffee grounds filler on the physical and mechanical properties of poly(lactic acid) bio-composite films

Abstract The objective of this research was to determine the effect of spent coffee grounds (SCG) filler on the physical and mechanical properties of poly(lactic acid) (PLA) bio-composite film. The bio-composite film was fabricated by a twin-screw and blow film extruder. SCG is the by-product of the coffee roasting process and were prepared by a ball mill and sieved to the size of 90 microns. The PLA/SCG bio-composite film was prepared using various SCG concentrations (0%, 5%, 7.5%, and 10% of SCG). The morphological properties of PLA/SCG bio-composite film were characterized by SEM. The matrix of polymer/SCG filler composites results showed that PLA/SCG is quite miscible when used SCG filler reinforced with PLA matrix that showed good distribution in the polymer matrix and SCG filler. The results of tensile properties showed the incorporation of SCG filler into PLA matrix and found that the PLA/SCG bio-composite film had increased elongation at break when the amount of SCG was increased. While a decrease in hardness and brittleness and also modulus at break of PLA. The melt flow index (MFI) of the bio-composite film increased when the concentration of SCG was higher. In the future, these PLA/SCG bio-composite films are to be developed into packaging films, nursery bag, and greenhouse bags due to the good mechanical properties and the ability to self-biodegrade in environmental conditions.