Preparation of composite phase change materials via single-step oil-in-oil emulsion templating approach

Herein, a novel, cost-effective and simple single-step synthesis method for the production of shape-stable composite phase change materials (PCMs) was developed. The method developed here is based on using oil-in-oil (o/ o) concentrated emulsions stabilized by the dual action of silane-modified SiO2 nanoparticles and a reactive surfactant. The key point here is that a paraffin-based PCM, n-hexadecane (HD), is used as the internal droplet phase, while an acrylate/diacrylate-based oil mixture is used as the external phase. Composite PCMs are directly obtained by thermally initiated polymerization of o/o emulsions. The main advantage of the developed method is that it does not require any separation or purification steps. The results show that the nanoparticle loading ratio has a significant effect on the PCM incorporation ratio, thermal energy storage properties, thermal stability and sealing property. The findings show that the latent heat of melting of the composite PCMs developed in this study reached up to 93.4 Jg- 1 at an incorporation ratio of 48%. This novel single-step method enables facile fabrication of shape-stable composite PCMs for a variety of thermal management applications.