Novel network structural PEG/PAA/SiO2 composite phase change materials with strong shape stability for storing thermal energy

Polyethylene glycol (PEG)/poly Acrylic acid (PAA)/silica (SiO2) composite phase change materials (PCMs) with strong shape stability were successfully synthesized by a simultaneous sol-gel reaction, and in situ free radical polymerization. The network structure, shape stability, phase change enthalpy, and thermostability of the prepared materials were characterized through FT-IR, DSC, TGA, and XRD. The synthesized PEG/PAA/SiO2 composite PCMs with a semi-interpenetrating network (semi-IPN) exhibited a high phase change enthalpy of 172.9 J/g and strong shape stability under 355 degrees C. The interaction between PEG and PAA/SiO2 network was also discussed in this paper, as well as the relationship between the interaction, energy density, and shape stability. The prepared PEG/PAA/SiO2 composite PCMs provided a novel method in preparing shape stable phase change materials.