Synergistic enhancement of creep resistance and thermal stability in epoxy nanocomposites reinforced with graphene nanoplatelets and halloysite nanotubes for optoelectronic applications

Abstract Epoxies used in optoelectronic applications are prone to creep due to low‐magnitude stresses caused by uneven thermal expansion, residual stresses, or component weight in elevated temperature environments. To address this, the effect of adding graphene nanoplatelets (GNP, 0.1–1 wt.%) and halloysite nanotubes (HNT, 1–10 wt.%) on the creep behavior of epoxy nanocomposites was investigated through 1‐h creep tests at 60°C under a 5 MPa load. Results showed that adding 0.1 wt.% GNP and 10 wt.% HNT led to significant reductions in strain rate, by 78.2% and 77.4%, respectively. A synergistic effect was observed when both nanoparticles were combined, improving dispersion and overall performance. The hybrid nanocomposite containing 1 wt.% HNT and 0.25 wt.% GNP demonstrated the most balanced improvement, with a 68.5% reduction in strain rate and enhanced dispersion. Characterization of the particle distribution using optical microscopy and SEM revealed that GNP particles tended to agglomerate more than HNT, while higher HNT loadings caused particle clustering and settling. The hybrid nanocomposite effectively mitigated these issues, making it a promising candidate for high‐temperature, high‐performance applications in optoelectronics, where improved mechanical and thermal stability are essential. Highlights 0.1 wt.% GNP and 10 wt.% HNT reduce the strain rate by 78.2% and 77.4%, respectively. Synergistic effect of 0.25 wt.% GNP and 1 wt.% HNT enhances epoxy creep resistance by 68.5%. GNP and HNT enhance creep strain by reinforcing the polymer network and load transfer. Optimized epoxy nanocomposite is ideal for high‐temperature optoelectronic applications.