Additively manufactured graphene enhanced nylon with inhibited coiling, entropically favorable linear conformations for hydrogen barrier applications

Abstract

Hydrogen is vital to sustainable energy systems, yet developing efficient and cost-effective gas barrier materials for hydrogen storage remains a challenge. This study investigates the hydrogen barrier performance of 3D-printed nanocomposites based on Polyamide-12 (PA12) filled with 0–2 wt% of few layer formulated graphene inks (PAG). A unique printing pattern facilitated uniform graphene dispersion within the polymer matrix. Mechanical tests revealed a 11 % increase in tensile strength and a 50 % rise in Young’s modulus at 2 wt% graphene, confirming effective reinforcement. Thermogravimetric analysis showed a 40 °C increase in degradation temperature, indicating enhanced thermal stability. Additionally, thermal conductivity improved by 170 %, and electrical percolation was achieved at just 0.5 wt% loading, enhancing electrostatic discharge safety. Molecular dynamics simulations demonstrated that graphene reduced polymer chain coiling, improved crystalline order, and strengthened hydrogen bonding within the matrix. Most notably, gas permeability tests revealed an 11-fold reduction in hydrogen permeability at 1.5 wt% filler, at least 40 % lower than state-of-the-art materials. These findings position 3D-printed graphene/PA12 nanocomposites as a superior solution for advanced, safe, and efficient hydrogen storage applications.