Poly(ethylene glycol) (PEG) is known to be very effective phase change material (PCM), which has been processed by various techniques. Efforts for development of better processing technique are always on, to make the process product and performance superior. Microwave technology based process development for the preparation of form stable phase change composites was attempted, with the motivation of establishing a green technique, which will be energy and time efficient and require minimum amount of solvent. The process could easily be scaled for large scale production of PCM blends. The microwave-assisted blending of PEG and cellulose acetate (CA) was carried out in various ratios resulting in the formation of biodegradable form-stable PCM. PEG acted as the latent heat storage material and cellulose acetate as the supporting material. As a result of microwave treatment, a high loading capacity of 96.5 wt% PEG was achieved without any leakage during the transition process. The blending was confirmed by Fourier transform infrared spectroscopy (FTIR) analysis which showed no chemical bonds between PEG and CA. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicated that maximum enthalpy of 155 J/g was attained and the material was found to have good thermal stability. The surface properties of these materials were studied by using contact angle for various weight percentages of PEG. The X-ray diffraction (XRD) investigation revealed that the crystallinity of the PEG-CA blend increased with increasing concentration of PEG. The morphology was studied with field-emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) suggesting a homogeneous network formation of the blend.(C) 2016 Elsevier Ltd. All rights reserved.