Influence of the lemongrass powder and polybutylene succinate on the properties of biocomposite films based on poly (lactic acid)

Abstract

The purpose of this research was to develop biocomposite films based on Poly (lactic acid); PLA, Polybutylene succinate; PBS and lemongrass powder; LE as a natural filler by twin-screw extruder and blow film extruder. The aim was to study the influences of LE and PBS on the physical and mechanical properties of biocomposite films. This work varied the weight percentage of PBS at 0, 10, and 20 wt% and varied the content of LE at 0, 2.5, 5.0, 7.5, and 10 wt%. The biocomposite films were characterized for physical properties (Color parameter and %UV transmittance), chemical properties (Fourier Transform Infrared Spectroscopy; FT-IR), mechanical properties (Tensile test), aging test at room temperature, and field testing. The mechanical properties of biocomposite films showed the addition of PBS into the PLA matrix increased the tensile strength and %elongation of biocomposite films by ~ 2–7 MPa and 1–2%, respectively. However, when increasing the amount of LE, the tensile strength and %elongation decreased. The color of the biocomposite films with the lemongrass powder gives a yellow-green shade, while ΔE of biocomposite film increases with a higher content of LE. The addition of LE improved the UV-light resistance properties of biocomposite film which is beneficial as a low %UV transmittance is important to prevent weeds growth. The %UV transmission of biocomposite films was reduced with increasing percentage of LE. Moreover, the biocomposite films after aging found that the color parameter and %UV transmittance only degraded less than 5%. This work, therefore, can be applied to agricultural products such as mulch film, while being biodegradable which could significantly reduce the agriculture plastic waste.