Hybrid polydopamine-MXene-MMT-silane nanocoating for multifunctional enhancement of basalt Fiber/PLA Composites: Mechanical, dynamic mechanical, thermal, and tribological performance

Basalt fiber (BF) reinforced PLA composites are limited by poor interfacial adhesion due to the chemically inert BF surface. This study addresses this challenge through a multi-stage surface nanoengineering strategy in which BF was first functionalized with silane (SBF), followed by the grafting of Ti₃C₂T_x MXene and MMT nanoparticles using a polydopamine (PDA) mediator. The optimal fiber loading (5 wt%) was established using silane-treated BF, after which the synergistic effects of the nanoparticle coatings were evaluated. Comprehensive structural, thermal, and mechanical characterization demonstrated that PMSBF5 achieved a 10.26% increase in tensile strength and a 54.25% rise in elongation at break, while PMMSBF5 further enhanced ductility to 25.52% (171.20% improvement). PMMSBF5 also showed a 68.44% increase in flexural strength, a 116.53% rise in flexural modulus, and a 77.65% improvement in storage modulus. Tribological testing revealed a 5.76% reduction in COF and a 53.10% decrease in wear rate for PMMSBF5. These results confirm that PDA-mediated nanoengineering significantly improves interfacial stress transfer, positioning these composites as strong candidates for high-performance automotive and biomedical applications.