PSI - Issue 52

Miray Yasar et al. / Procedia Structural Integrity 52 (2024) 165–175 Miray Yasar et. al. / Structural Integrity Procedia 00 (2019) 000 – 000

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4. Conclusion This study explores an integrated sensing mechanism as an alternative to external sensors for structural health monitoring of fibre-reinforced composites. MWCNTs included PVDF solution was impregnated into a PPS veil to create a stable piezoelectric PVDF layer. Carbon fibre reinforced recyclable thermoplastic composites were then produced by sandwiching the PVDF layer between carbon fabrics. Tests, including bending, shear strength, and fracture toughness, were conducted on composites with nonperforated and perforated PVDF layers. The flexural strength and modulus decreased after adding the PVDF layer, but the bending strength and modulus increased by 23.74% and 5.63%, respectively in the perforated specimens compared to non-perforated ones. However, the adhesion between the PVDF layer and the resin/fibre system needs improvement, as indicated by deteriorated fracture toughness and ILSS results. The perforated PVDF layer in carbon fabric reinforced composites generated a voltage output of 100mV. With further improvements, these composites have a potential for sensing and actuating applications, such as piezoelectric sensors, energy harvesting devices, and robotics. Additionally, the composite material’s low cost, lightweight, and flexible nature make it a promising candidate for various electronic devices. Acknowledgements This publication has emanated from research conducted with the financial support of Science Foundation Ireland under Grant number 16/RC/3872. For the purpose of Open Access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission . References Abdolmaleki, H., Agarwala, S., 2020. PVDF-BaT iO3 Nanocomposite Inkjet Inks with Enhanced β -Phase Crystallinity for Printed Electronics. Polymers 12, 2430. https://doi.org/10.3390/polym12102430 Aqeel, S.M., Wang, Z., Than, L., Sreenivasulu, G., Zeng, X., 2015. Poly(vinylidene fluoride)/poly(acrylonitrile) – based superior hydrophobic piezoelectric solid derived by aligned carbon nanotubes in electrospinning: fabrication, phase conversion and surface energy. RSC Adv. 5, 76383 – 76391. https://doi.org/10.1039/C5RA11584A Bhavanasi, V., Kumar, V., Parida, K., Wang, J., Lee, P.S., 2016. Enhanced Piezoelectric Energy Harvesting Performance of Flexible PVDF-TrFE Bilayer Films with Graphene Oxide. ACS Appl. Mater. Interfaces 8, 521 – 529. https://doi.org/10.1021/acsami.5b09502 Bhudolia, S.K., Joshi, S.C., 2018. Low-velocity impact response of carbon fibre composites with novel liquid Methylmethacrylate thermoplastic matrix. Composite Structures 203, 696 – 708. https://doi.org/10.1016/j.compstruct.2018.07.066 Cai, X., Lei, T., Sun, D., Lin, L., 2017. A critical analysi s of the α, β and γ phases in poly(vinylidene fluoride) using FTIR. RSC Adv. 7, 15382 – 15389. https://doi.org/10.1039/C7RA01267E Groo, L., Inman, D.J., Sodano, H.A., 2021. Dehydrofluorinated PVDF for structural health monitoring in fibre reinforced composites. Composites Science and Technology 214, 108982. https://doi.org/10.1016/j.compscitech.2021.108982 Haghiashtiani, G., Greminger, M.A., 2015. Fabrication, polarization, and characterization of PVDF matrix composites for integrated structural load sensing. Smart Mater. Struct. 24, 045038. https://doi.org/10.1088/0964 1726/24/4/045038 Hu, X., You, M., Yi, N., Zhang, X., Xiang, Y., 2021. Enhanced Piezoelectric Coefficient of PVDF-TrFE Films via In Situ Polarization. Front. Energy Res. 9, 621540. https://doi.org/10.3389/fenrg.2021.621540 Jin, C., Hao, N., Xu, Z., Trase, I., Nie, Y., Dong, L., Closson, A., Chen, Z., Zhang, J.X.J., 2020. Flexible Piezoelectric Nanogenerators Using Metal-doped ZnO-PVDF Films. Sens Actuators A Phys 305, 111912. https://doi.org/10.1016/j.sna.2020.111912 Kaspar, P., Sobola, D., Částková, K., Knápek, A., Burda, D., Orudzhev, F., Dallaev, R., Tofel, P., Trčka, T., Grmela, L., Hadaš, Z., 2020. Characterization of Polyvinylidene Fluoride (PVDF) Electrospun Fibres Doped by Carbon Flakes. Polymers 12, 2766. https://doi.org/10.3390/polym12122766