Hydrolytic aging of a biopolymer reinforced with Alfa fiber treated with dispersing agent

Abstract

The aging of materials is a degradation or a slow evolution of the properties of the material resulting from its intrinsic instability or caused by more or less aggressive external factors. Based on the literature, the degradation of polylactic acid (PLA) biocomposites mainly consists of hydrothermal degradation and photodegradation, the PLA/natural fibers interface is one of the main factors affecting the rate of hydrolytic degradation. With the addition of vegetable fibers, greater degradation is observed. Thus, because of their hydrophobicity, the biocomposite obtained has a greater moisture uptake causing swelling at the fiber/matrix interface. This causes cracking and degradation by more significant chain cuts. This work reports on the hydrolytic aging of biocomposites which were composed of Alfa fiber and Polylactic acid (PLA) prepared by extrusion. To improve the fiber/matrix compatibility, the Alfa fiber has been treated with a dispersing agent which is BYK W-980. Spectroscopic (FTIR), thermal, and water absorption tests before and after hydrolytic aging of biocomposites have been studied and compared. The results revealed that PLA/Alfa biocomposites in the presence of BYK W-980 are more resistant to hydrolytic aging compared to untreated composites.