Impact and fatigue tolerant natural fibre reinforced thermoplastic composites by using non-dry fibres

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2022-10, Vol.161, p.107110, Article 107110
• Main Authors: Javanshour, F., Prapavesis, A., Pournoori, N., Soares, G.C., Orell, O., Pärnänen, T., Kanerva, M., Van Vuure, A.W., Sarlin, E.
• Format: Article
• Language: English
• Subjects: A. Thermoplastic matrix; B. Adhesion; B. Debonding; B. Delamination
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2022.107110

This article introduces stiff and tough biocomposites with in-situ polymerisation of poly (methyl methacrylate) and ductile non-dry flax fibres. According to the results, composites processed with non-dry fibres (preconditioned at 50% RH) had comparable quasi-static in-plane shear strength but 42% higher elongation at failure and toughness than composites processed with oven-dried fibres. Interestingly, the perforation energy of flax–PMMA cross-ply composites subjected to low-velocity impact increased up to 100% with non-dry flax fibres. The in-situ impact damage progression on the rear surface of composites was evaluated based on strain and thermal field maps acquired by synchronised high-speed optical and thermal cameras. Impact-induced delamination lengths were investigated with tomography. Non-dry fibres also decreased the tension–tension fatigue life degradation rate of composites up to 21% and altered the brittle failure mode of flax–PMMA to ductile failure dominated by fibre pull-out.