Effect of oligomers from epoxidized soybean oil and sebacic acid on the toughness of polylactic acid/bamboo fiber composites

Abstract The application of bamboo fibers (BFs) to reinforce the impact strength of polylactic acid (PLA) is attractive because of its low cost and high specific strength. However, the main disadvantages of PLA/BF composites are their low compatibility and poor interfacial adhesion caused by different surface energies. In this work, a bio‐based compatibilizer is used to modify PLA/BF composites with a BF content up to 30 wt%. First, sebacic acid (SA) and epoxidized soybean oil (ESO) are reacted to obtain ESO‐SA oligomers with different branching and crosslinking structures. Next, ESO‐SA is incorporated into a PLA/BF composite through dynamic vulcanization, and fully bio‐based PLA/BF/ESO‐SA ternary composites are prepared. Compared to the PLA/BF composite without ESO‐SA addition, the impact strength of PLA/BF/16ESO‐SA 12 increases from 5.8 to 14.55 KJ/m 2 . The toughening mechanism results confirm that the chemical structure of ESO‐SA is the key indicator of the toughening efficiency.