PSI - Issue 82

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2026) 000–000

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ScienceDirect

Procedia Structural Integrity 82 (2026) 98–106

© 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID organizers with a value of 73.2 GPa. ILSS was improved by 12.4% to a value of 55.8 MPa. Scanning electron microscopy (SEM) images revealed possible evidence that interleaved PES films prevented crack propagation to the fibre/epoxy interface, leading to the increase in Mode I fracture toughness observed. Disparities in fibre volume fraction (FVF) between control and PES interleaved samples place some doubt on the validity of these results. © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID organizers Keywords: Carbon fibre; Nanoparticles; Fracture toughness; Microstructural analysis 8th International Conference on Structural Integrity and Durability (ICSID2025) Interlaminar fracture toughness of carbon fibre epoxy composites interleaved with polyethersulfone film Jet Best a , Vishnu Prasad a, *, Neal Murphy a , Alojz Ivankovic a a University College Dublin, Dublin, Ireland Abstract Carbon fibre reinforced Polymer (CFRP) samples containing interleaving Polyethersulfone (PES) films were tested for Mode I fracture toughness, Flexural strength and Interlaminar Shear Strength (ILSS). Samples were produced using Uni-Directional carbon fibres (UD-CF) and Easy Composites IN2 (EC IN2) epoxy resin via the Vacuum-assisted resin transfusion method (VaRTm). The mechanical properties of the EC IN2 resin were assessed at the elevated curing temperatures necessary for PES film phase separation by Dynamic Mechanical Analysis (DMA). PES films of thickness 0.05 mm and areal weight 10 g/m 2 were manufactured by casting in a polycarbonate tray. The phase-separation behaviour of the PES films in EC IN2 resin was examined. Results show that PES film phase-separation could not be achieved, even at elevated curing temperatures. CFRP samples were interleaved with PES films. Results for PES interleaved CFRP samples show 24.7% improved Mode I fracture toughness over control samples with an average G IC of 1.02 kJ/m 2 . Flexural strength decreased by 9.6% to a value of 718 MPa. Flexural modulus remained unaffected,

* Corresponding author. Tel.: +353 892574615. E-mail address: vishnu.prasad1@ucd.ie

2452-3216 © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID organizers

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ICSID organizers 10.1016/j.prostr.2026.04.016