Green Composites from Plasticized Cellulose Acetate and Microcrystalline Cellulose: Effect of Maleated Cellulose Acetate on the Biocomposite Performance

Novel green composites were engineered from microcrystalline cellulose (MCC) and plasticized cellulose acetate (pCA). The influence of the MCC content and effect of maleic anhydride-grafted cellulose acetate (MA-g-CA) on the performance of green composites were also analyzed. Green composites were developed with up to 15 wt % MCC with different concentrations of MA-g-CA (2, 4, and 7 wt %). Green composites with 15 wt % MCC showed an increase of 21% and 5% in tensile and flexural moduli, respectively, compared to neat pCA, leading to enhanced stiffness and rigidity of the composite material. After the addition of MA-g-CA, the impact strength and elongation at break increased by 22% and 20%, respectively, than their counterparts without MA-g-CA, indicating its plasticizing effect. Scanning electron microscopy confirmed an adequate dispersion of filler particles after the addition of MCC to the CA matrix. The addition of 4% MA-g-CA to 15 wt % MCC green composites exhibited an improved fiber-matrix adhesion. This gave comparable tensile strength and enhanced tensile modulus compared to the neat matrix. Also, the 7% MA-g-CA-added samples showed the highest extensional viscosity of the resulting green composites.