Synergistic enhancement of mechanical and thermal properties in basalt fiber reinforced composites through nanotube and graphene bridging structure: A multi-scale simulation

Abstract

Functionalizing carbon nanotubes and graphene in fiber-reinforced composites can enhance interfacial bonding while compromising the nanoparticles’ intrinsic thermal conductivity. Herein, a multi-scale simulation approach is introduced to design an interface structure, achieving synergistic improvement in both interfacial strength and thermal conductivity. The interface structure employs a combination of (3-Ureidopropyl)trimethoxysilane (SCA6) modified carbon nanotubes (CNT) and graphene (GR) overlap. Molecular dynamic simulations elucidate the formation of heat transfer pathways through SCA6-modified CNT and GR networks, facilitating multidirectional thermal transport. SCA6 modification not only optimizes phonon coupling between nanofilers and PA66 but also refines interfacial interactions, mitigating interfacial phonon scattering and fortifying resin-nanoparticle bonding. Interfacial traction-separation simulation (Mode-I, II, and mixed modes) demonstrates substantial improvements in BF-PA66 adhesion, with Mode-I separation stress exhibiting a transition from 0.25 MPa to 0.32 MPa. Electrostatic interactions emerge as the primary driver of interfacial enhancement. Finite element analysis confirms improved heat transfer and structural integrity of the composite, evidenced by a von Mises stress reduction from 3.75 × 10² MPa to 3.47 × 10² MPa in the BF-SCA6/CNT-GR/PA66. Experimental validation shows a 4.1-fold increase in thermal conductivity accompanied by mechanical property improvements, corroborating the effectiveness of the multi-scale simulation design.