Guayule-based natural rubber (G-NR) is a sustainable alternative to Hevea-based natural rubber (H-NR), yet its elastocaloric behavior remains largely unexplored. In this work, peroxide-crosslinked G-NR and H-NR with different network chain densities are investigated. Single uniaxial tensile tests are combined with in-situ infrared thermography together with a modeling approach using Arruda–Boyce model and the thermoelastic model. It is shown that G-NR exhibits a delayed onset of strain-induced crystallization (SIC), while maintaining an elastocaloric response comparable to the one of the H-NR. Increasing the network chain density significantly promotes SIC in G-NR by reducing the strain at SIC onset, while the effect is less pronounced in H-NR. Under continuous cyclic loading, G-NR can maintain stable temperature span with cycles at around 8°C, while the dissipated mechanical energy progressively decreases, resulting in a material coefficient of performance, COPmat, exceeding 11 after 20 cycles. These results indicate that Guayule-based Natural Rubber is a promising sustainable elastocaloric material for its possible integration in solid-state cooling devices.
Hydrogen storage and transportation remain major bottlenecks in the development of the hydrogen energy industry. Polyethylene-based composites are considered promising alternatives owing to their excellent processability, corrosion resistance, and lightweight characteristics. However, how to maintain the excellent processing properties of polyethylene while achieving a synergistic improvement in its physical, mechanical and application properties remains a key scientific issue that hinders its engineering application. In this study, Mg(OH)2, ZnB, and CB nanofillers were coated onto polyethylene particles through a slurry-coating process and by combining the steel wire mesh reinforcement strategy, a layered structure PEc/Fe/PEc composite material was prepared to achieve the synergistic optimization of mechanical, electrical, flame-retardant, and hydrogen-barrier properties. The results showed that the prepared PEc/Fe/PEc composite exhibited a tensile strength of 36.31 MPa and a volume resistivity of 2.96 × 109 Ω cm. Meanwhile, the peak heat release rate (pHRR) and total heat release (THR) were reduced to 500.61 kW m−2 and 96.4 MJ m−2, respectively. In addition, the composite demonstrated significantly improved hydrogen-barrier performance and electrical breakdown resistance. The enhanced performance was mainly attributed to the synergistic effect of the dense barrier network constructed by nanofillers and the reinforced sandwich structure formed by the iron wire mesh, which promoted structural stability and multifunctional characteristics.
