Coaxial Electrospun <scp>SMPU</scp> @ <scp>PEG</scp> Composites for Enhanced Thermal Regulation on Curved Surfaces

ABSTRACT Phase change materials (PCMs) hold promise for advanced thermal management, yet their rigid behavior often restricts effective contact with curved or irregular surfaces—leading to inefficient heat transfer. To address this gap, we report a coaxially electrospun fiber composite integrating shape memory polyurethane (SMPU) and polyethylene glycol (PEG). The rationale behind this study lies in the need to overcome air gaps that arise when conventional PCMs fail to conform to nonplanar substrates, compromising the latent heat exchange crucial for thermoregulation. Leveraging coaxial electrospinning, we tuned fiber alignment and PEG content to fabricate composites capable of both shape fixation and phase‐change–assisted temperature control. Mechanical and shape memory tests confirmed performance, with final shape fixation and recovery rates exceeding 80% and 90%, respectively. Crucially, pre‐deforming the SMPU@PEG membrane to match complex substrates reduced interfacial air layers and increased the temperature difference by up to 6.77°C and 3.67°C compared with a non‐pre‐deformed sample. This improved thermal regulation underscores the synergistic advantage of shape memory functionality and phase‐change latent heat in optimizing conformal contact and heat transfer. Our study both enhances comprehension of merging shape memory features with PCMs and has real‐world uses for wearable tech reliant on efficient curved—surface thermoregulation.