Flexible Phase-Change Films with Exceptional Water and Temperature Resistance for Smart Personal Thermal Protection

Area of Science:

• Materials Science
• Nanotechnology
• Textile Engineering

Background:

• Personal thermal protection is critical in extreme environments, with rising global temperatures exacerbating heat stress challenges.
• Phase-change materials (PCMs) offer innovative thermal regulation by absorbing/releasing heat during phase transitions.
• Current PCMs face limitations in wearable systems due to mechanical properties, latent heat, temperature resistance, and response time.

Purpose of the Study:

• To develop a flexible composite PCM film for enhanced wearable thermal protection.
• To address the limitations of traditional PCMs in mechanical properties and thermal response.
• To investigate the synergistic effects of superhydrophobic silica aerogel particles (SSAPs) and a cross-linked poly(ethylene glycol) (PEG) network.

Main Methods:

• Incorporation of SSAPs into a cross-linked PEG network to create a composite PCM film.
• Characterization of the film's mechanical properties, latent heat, and thermal response.
• Evaluation of water resistance and synergistic thermal insulation provided by SSAPs.

Main Results:

• The composite PCM film exhibited self-support, high flexibility, and enhanced heat resistance.
• Achieved a latent heat range of 113.1–146.9 J g^-1 with adjustable SSAP content.
• Demonstrated a 2.65-fold enhancement in temperature drop (13.8 °C at 80 °C) and a 275% deceleration in heating rate compared to pure PEG.

Conclusions:

• A novel strategy for preparing flexible, temperature-resistant PCM films with improved thermal regulation was proposed.
• The composite PCM film shows significant potential for advanced wearable thermal protection systems.
• The study highlights how lower latent heat can paradoxically lead to enhanced thermal regulation capabilities.