Mechanical and Moisture Absorption Characterization of Pla Composites Reinforced with Nano-Coated Flax Fibers
This study aims at improving the interfacial adhesion between the two components (fibers and matrix) of bio-based fiber-reinforced polymers (FRP) to enhance their mechanical properties and limit water absorption through them. Two composites were processed; one containing as-received fibers and the other one containing coated fibers. One sample of pure PLA was also made as reference. The two composites were hot pressed and consisted in a stacking of 4 PLA sheets and 3 pieces of flax fabric. Technical fibers were observed by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM) to study the quality of their surface and of the coating dispersion. A water absorption test was carried out on the 3 samples by placing them in a 50 °C water bath until saturation to investigate the influence of the coating on water diffusion. Finally, mechanical properties of the different composites were investigated by tensile and short beam shear (SBS) testing. This research revealed significant improvements concerning the quality of the fibers surface and the interface between them and the matrix and thus, enhanced mechanical properties. It also showed that the coating did not have any effect on the water absorption speed but it blunted the voids, defects and filled the fibers lumen, which led to a decrease of water uptake at saturation.
Authors: Marie Bayart, Florent Gauvin, MReza Foruzanmehr, Mathieu Robert, and Saïd Elkoun
Conference: SAMPE Seattle 2017