Interlaminar Shear Strength Characteristics of Graphene Nanoplatelets and Basalt Fabric Reinforced In-Situ Polymerisable Acrylic-Based Nanocomposites

The excellent processability and strong environmental sustainability contribute to the increasing use of basalt-based composites in various construction industries. This study examines the interlaminar shear strength (ILSS) of sustainable basalt fibre-reinforced polymer composites (BFRP), with a focus on the performance of a thermoplastic Elium-based matrix and a conventional thermoset epoxy matrix. Basalt fibres were surface-modified with dopamine (Do) and dopamine-graphene nanoplatelet (Do-GNP) coatings to enhance fibre/matrix interaction. Melamine was used to functionalise GNP to enhance dispersion within the DO. Coating Bf with Do and Do-GNP improved the ILSS values, even after normalising the results. Short beam shear (SBS) testing showed that the BF/Elium composite reached a maximum load 83% greater than that of the BF/epoxy composite, with ILSS values increasing by 35%. DO and Do-GNP coatings further improved the ILSS of the BF/Elium composites by 6% and 1%, respectively. Scanning electron microscope (SEM) analysis confirmed reduced shear cracking and delamination in the modified composites, which correlated with improved ILSS performance.