Physical, Mechanical and Antibacterial Properties of Biodegradable Bioplastics from Polylactic Acid and Corncob Fibers with Added Nano Titanium Dioxide

Abstract

The objective of this research was to investigate the mechanical, physical and antibacterial activities and biodegradability properties of bioplastics from polylactic acid (PLA) and corncob fibers (CF). The bioplastics were prepared by mixing PLA and CF at different ratios (100:0, 90:10, 80:20, 70:30, 60:40 and 50:50 % w:w) in the internal mixer and molding was done by using the hot-compressing molding method. The results demonstrated the decrease in tensile strength and elongation at break with increased in CF. Young’s modulus was found to be highest in the 70 %PLA: 30 %CF bioplastic, however, it decreased when the CF was increased. The hardness and water absorption were dependent on CF concentration. SEM analysis revealed the well dispersion of CF in PLA matrix. PLA matrix and increasing of CF induced in CF agglomeration. To develop PLA/CE plastic for antibacterial food packaging application, its antibacterial activity was conducted. The antibacterial determination revealed that 70 %PLA: 30 %CF containing 2 % TiO2 bioplastic exhibited the highest inhibition against E. Coli, S. aureus and B. subtilis. Additionally, the biodegradable character of the bioplastic was dependent on concentration and time, as the bioplastic weight loss was increased when the concentration of CF and biodegradation period were increased. The results obtained from this research indicate that the bioplastics prepared from polylactic acid and corncob fibers is biodegradable bioplastics and can be used as alternate synthetic plastics. The bioplastic with 2 %TiO2 added can be utilized potentially for expected antibacterial food packaging.