Multi-functional phase change materials with asymmetric thermo-responsive properties

While significant progress has been made in thermal management materials for conventional environments, the development of phase change materials (PCMs) with robust adaptability for complex operational scenarios remains nascent. This study presents an asymmetric temperature-responsive PCM system engineered through the integration of a poly(butyl methacrylate) (PBMA) polymer network, tetradecanol (TD) phase-change component, and carbon nanotubes (CNTs). Due to terminal hydroxyl groups of TD preferentially crosslink with PBMA's side chains, the composite with M PBMA / M CNTs mass ratio of 14.4:1 enables a temperature-dependent transition from an elastoplastic state at 30 °C to an elastic state at 70 °C (fracture strain of 393 % and fracture stress of 376 kPa). The PBMA/TD/CNTs composite achieves a Δ H value of 98.2 J g −1 , corresponding to 1.046 W m −1  K −1 of the thermal conductivity. Notably, the CNTs dispersed within the melted composite undergo electric field-induced directional alignment, resulting in an increase in its electrical conductivity from 5.0 × 10 −4  S m −1 at 45 °C to 0.2 S m −1 at 125 °C. This asymmetric thermo-responsive mechanism confers the composite with distinctive thermal regulation properties: rapid heat absorption coupled with controlled heat dissipation.