This Work mainly involved the preparation and characterization of form-stable polyethylene glycol (PEG)/silicon dioxide (SiO(2)) composite as a novel solid-liquid phase change material (PCM). In this study, the polyethylene glycol/silicon dioxide composites as form-stable, solid-liquid phase change material (PCM) was prepared. In this new material, the polyethylene glycol acts as the latent heat storage material and silicon dioxide serves as the Supporting material, which provides Structural strength and prevents the leakage of the melted polyethylene glycol. Results indicated that the composite remained solid when the weight percentage of silicon dioxide was higher than 15%. Moreover, the polyethylene glycol was observed to disperse into the network of the solid silicon dioxide by investigation of the structure of the composite PCMS using a scanning electronic microscope (SEM). The properties of the porous materials and phase change materials were characterized using Fourier transformation infrared spectroscope (FTIR). The transition process was observed using polarizing optical microscope (POM) and dynamic thermo mechanic analysis (DMA). The melting temperatures and latent heats of the form-stable PEG/SiO(2) Composite PCMs were determined using differential scanning calorimeter (DSC). (c) 2008 Elsevier Ltd. All rights reserved.