Synthesis, Characterization and Thermal Properties of Hybrid-Microencapsulated Phase Change Materials Based on ZnO Nanoparticles

The use of organic polymers as shell to encapsulate the organic Phase Change Materials (PCMs) presents some disadvantages because of their being highly flammable, having a poor thermal stability and low thermal conductivity. The use of hybrid materials composed of organic and inorganic materials constitutes a promising way to improve chemical and thermal properties of microencapsulated PCMs (MEPCMs). In this research, organic-inorganic hybrid-MEPCMs were synthesized by utilizing paraffin as core and urea-formaldehyde (UF) polymer as shell, and ZnO metal oxide nanoparticles. The prepared samples were characterized using Fourier Transform Infrared spectroscopy, X-Ray Diffraction, Scanning Electron Microscopy, Differential Scanning Calorimetry and Thermogravimetric analysis. The obtained results showed that the synthesized hybrid-MEPCMs are in spherical and irregular forms and present a rougher surface due to the presence of metal oxide nanoparticles which are scattered onto the surface of microcapsules or wrapped by UF shell material. They also indicated the probable improvement of hybrid-MEPCMs' thermal stability. In this work, the influence of metal oxides content on structural, morphological and thermal properties of hybrid-MEPCMs is discussed.