Preparation and Evaluation of Waterborne Polyurethane Encapsulating Stearyl Alcohol as a Shape-Stabilized Phase Change Material

The stearyl alcohol was encapsulated with waterborne polyurethane (WPU) to prepare a shape-stabilized phase change materials (PCMs) containing stearyl alcohol up to 50 wt%. The particle size analysis and the morphology observed by scanning electron microscope showed that the encapsulated particle size was several micrometers. Thermogravimetric analysis demonstrated that the stearyl alcohol was effectively encapsulated by WPU with marginal loss. The heat of fusion of the particle encapsulating 30 wt% stearyl alcohol was 90-100 J/g, which was larger compared with those of previous reports on PCMs encapsulated by polyurethanes. The shape stability of stearyl alcohol above melting temperature was evidently improved by the encapsulation with WPU.