High‐Performance Elastocaloric Refrigeration via Liquid Metal‐Enhanced Polyurethane

Abstract Solid‐state refrigeration technology based on elastocaloric effect (eCE) has garnered widespread attention as an emerging green refrigeration technology. While shape memory polymers (SMPs) offer substantial temperature changes (Δ T ) with relatively low applied stress compared to alloys, their limited thermal conductivity poses a significant challenge for efficient heat exchange. Here, low‐melting‐point GaInSn liquid metal (LM) is introduced into thermoplastic polyurethane (TPU) to develop TPU@LM shape memory polymer composites by solvent casting method. The LM with high thermal conductivity and fluidity, is uniformly dispersed in TPU, forming a dense thermal conduction network within the TPU matrix that increases thermal conductivity by 164%. Furthermore, this larger thermal conductivity improves the eCE significantly, achieving a maximum Δ T of 8.7 K at an elongation ratio of 3, ≈30% higher than pure TPU. The fluidity of LM aids the rotational rearrangement of fiber chains, benefiting stress‐induced crystallization recovery and reducing loading stress and residual strain during the eCE cycle. The incorporation of LM enhances Δ T and cooling range while achieving greater cooling power at higher frequencies. Compared to typical eCE alloys and polymers, TPU@LM demonstrates a specific temperature change (Δ T / σ ) 35 times higher than the average of other materials, significantly advancing eCE technology.