Investigating the Thermal Properties of Hydrated Salt Phase Change Material Nanocomposites in the Prevention of Heat Stress



E Rahimi ELNAZ ; S Kalantary SABA ; A Babapoor AZIZ ; H Dehghan HABIBOLLAH ; A Kazemnejad ANOUSHIRVAN ; Mrm Esmaeelpour Mohammad Reza MONAZZAM
Source: Journal of Health and Safety at Work Published:2025

Abstract

Introduction: Wearable thermal management systems and phase change materials (PCMs) have emerged as effective solutions for regulating body temperature and storing thermal energy. This study focuses on synthesizing and thermal optimizing a sodium sulfate decahydrate-based nanocomposite incorporating various nanoparticles to improve its performance for personal thermal regulation applications. Material and Methods: The composite was prepared using sodium sulfate decahydrate as the base PCM. Potassium chloride (KCl) was added to adjust the melting point, borax (STD) served as a nucleating agent, and sodium polyacrylate (SPA) was included as a thickening agent to suppress phase separation. To evaluate the effect of nanoparticle additives, 0.05 wt.% of aluminum oxide (Al₂O₃), iron oxide (Fe₂O₃), graphene oxide (GO), and titanium dioxide (TiO₂) were separately incorporated into the base formulation. A field emission scanning electron microscope (FESEM) was used to analyze the surface morphology of the resulting nanocomposites. Differential scanning calorimetry (DSC) assessed thermal properties, including phase transition temperatures (melting and freezing points) and latent heat. Results: Differential scanning calorimetry (DSC) analysis indicated that sample S-5-5 comprising sodium sulfate decahydrate with 3 wt.% KCl, 5 wt.% STD and SPA exhibited a melting temperature of 29.5 °C and a latent heat of 120 J/g. This composition remained stable without phase separation. The incorporation of nanoparticles raised the melting point of the base PCM by 0.6 to 1.72 °C. Aluminum oxide (Al₂O₃) and iron oxide (Fe₂O₃) reduced the latent heat of fusion, whereas GO and TiO₂ increased it. Conclusion: These findings confirm that the thermal properties of sodium sulfate decahydrate-based PCMs can be tailored by including specific additives and nanoparticles. Hydrated salt nanocomposites demonstrate strong potential as PCMs for wearable body temperature regulation. © 2025 Elsevier B.V., All rights reserved.