Synthesis, characterization, and thermal energy storage properties of a novel thermoplastic polyurethane phase change material

Abstract This study focuses on the design and synthesis, thermal energy storage properties and thermal stability of a novel thermoplastic polyurethane solid–solid phase change material (PUSSPCM) for thermal energy storage. The PUSSPCM was synthesized via the two-step condensation reaction of 4,4'-diphenylmethane diisocyanate, polyethylene glycol and a novel tetrahydroxy compound (terephthalic acid bis-(2-hydroxy-1-hydroxymethyl-ethyl) ester) and characterized by Fourier transform infrared spectroscopy and 1 H nuclear magnetic resonance techniques. Thermal energy storage properties and thermal stability of as-synthesized PUSSPCM were also measured. DSC results indicate that the phase change temperatures and latent heats of the as-synthesized PUSSPCM are in the ranges of 22.4–48.4 °C and 143.9–153.5 J/g, respectively. TGA results confirm that the initial degradation temperature of the PUSSPCM is at 323 °C, which proves that PUSSPCM has good thermal stability. More significantly, the as-synthesized PUSSPCM can be directly melted and processed, and has a wide processing temperature range. Based on these results, it can be concluded that the synthesized PUSSPCM, as a novel phase change material (PCM), has significant energy storage potential due to its suitable phase change temperatures, higher latent heats, good thermal stability and processing performances.