Improvement on the properties of microcrystalline cellulose/polylactic acid composites by using activated biochar

Abstract Elucidating the effect of activated biochar (AB) on the thermal and mechanical properties of microcrystalline cellulose (MCC)/polylactic acid (PLA) composites is one of the objectives of this research while the ultimate goal is to obtain predictive insight into the optimized process in reducing cost and improving properties of biocomposites. AB was used as a filler to improve the properties of MCC/PLA composites by compounding and injection molding in this study, and the thermal and mechanical properties of the composites were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), static mechanical analysis (SMA) and dynamic mechanical analysis (DMA). DSC showed that the addition of AB promoted the early onset of exothermic crystallization. Besides, the increase of glass transition temperature and melting temperature and the delay of degradation of MCC/PLA composites shown by DSC and TGA suggested the improvement of thermal properties with the addition of AB. In addition, SMA showed that better tensile strength (16.37 MPa), tensile modulus (3.84 GPa), flexural strength (53.81 MPa), flexural modulus (5.81 GPa), impact strength (3.67 kJ/m2) were obtained with the addition of AB, and DMA revealed that the addition of AB improved the stiffness, elasticity, creep resistance and anti-stress relaxation ability of MCC/PLA composites. The abundance and flexibility of AB would be practically helpful to convert the wastes to cleaner production at a low cost.