Strengthening effect of pea dietary fiber on mechanical properties and degradability of polylactic acid

Abstract Pea dietary fiber (PDF) was filled into polylactic acid (PLA) to prepare PLA/PDF composites with different PDF contents (0%, 2.50%, 5.00%, 7.50%, 10.00%) by hot melt extrusion. The thermodynamic properties, microstructure, degradability of PLA/PDF composites were investigated. Results showed that the continuity, smoothness and mechanical properties of the PLA material structure were improved, which was attributed to the defects of the PLA material structure were significantly compensated by the appropriate amount (≤ 5.00%) of PDF. The degradation experiment exhibited that the degradation rate of PLA could be significantly improved by using PDF as filler. The degradation rate of 10.00% PLA/PDF composite at the end of soil, aqueous soil biodegradation and in vitro degradation experiments was 134.09%, 210.00% and 500.00% higher than that of PLA material containing 0% PDF, respectively. In summary, PLA/PDF composite containing 5.00% PDF had the optimum comprehensive properties in terms of smooth surface, good mechanical properties and excellent degradability. That possessed huge market potential in the field of material processing. This study combined materials science with food science, which broadened the new research ideas in the field of polylactic acid modification and PDF application.