Waste Cellulose Fibers Reinforced Polylactide Toughened by Direct Blending of Epoxidized Soybean Oil

Abstract

An eco-friendly method has been used to synthesize ductile and toughen composites from completely renewable resources by exploring poly(lactic acid) (PLA)’s sophisticated properties in terms of strength, stiffness as well as its brittleness. Due to their excellent mechanical properties and potential for sustainable manufacturing, nano-cellulose as a bio-based organic filler, have been broadly used in a variety of polymer reinforcement. Herein, waste cellulose fibers (WCF) within the nanometer range were used as a filler to blend with PLA using lab-scale twin-extruder, with and without epoxidized soybean oil (ESO) as a reactive plasticizer. To investigate their effect on the mechanical properties like Young’s modulus, strength, toughness, and ductility, various constituents of ingredients were selected. An increase in elongation-at-break (5.1 to 60.8 %), bending strain (5.9 to 9.4 %) and impact strength (2.05 to 6.1 kJ/m2) in comparison to neat PLA was found in PLA/WCF/ESO ternary composites, leading to reduced glass transition (Tg) and crystallization temperature (Tc) as confirmed by a differential scanning calorimetry (DSC) measurements. An increase in char yield was also observed from the thermogravimetric analysis (TGA), which was clearly associated with the flame potency. Chemical interactions were investigated by Fourier transform infrared (FTIR) spectroscopy by examining shifts in peak positions. A scanning electron microscope (SEM) was utilized systematically to analyze the toughening mechanism.