Enhanced mechanical and thermal properties of expanded graphite/ice phase change materials through in-situ polymerization of sodium polyacrylate in cold chain logistics

The growing demand for high-quality food and medicine has propelled the expansion of the global cold chain logistics market. Passive cold chain logistics, utilizing phase change materials (PCMs), has emerged as an advanced and environmentally friendly technology. This study addresses current challenges in phase change materials, including leakage and low mechanical strength, by introducing a novel composite phase change material (cPCM) with enhanced thermal conductivity and flexibility. The expanded graphite-sodium polyacrylate (EG-PAAS) dual network framework, formed through vacuum impregnation and in-situ polymerization, results in a cPCM (H2O@EG-PAAS) with high thermal conductivity (5.64 W·m−1·K−1) and substantial latent heat (263.1 J·g−1). Addressed prolonged cooling times in phase change materials, accomplishing rapid cooling and uniform temperature distribution. The 8 L insulation box was maintained below 8 °C for 1124.1 min, rendering it a promising solution for efficient and flexible cold chain transportation.