Thermal properties of lauric acid-palmitic acid eutectics/polyvinyl butyral/carbon nanofibers as shape-stable phase change materials

• The CPCM was prepared using PVB as supporting material and CNF as an additive. • The CPCM can prevent the leakage of the PCM and had good thermal stability. • The CPCM6 with melting latent heat of 131.20 J/g behaves good thermal performance. • The CPCM6 with thermal conductivity of 0.40 W/(m·K) has a potential application. In this work, shape-stable composite phase change materials (CPCM) were prepared, which consist of lauric acid (LA)–palmitic acid (PA) eutectics, polyvinyl butyral (PVB) and carbon nanofibers (CNF). The PVB acted as supporting material, and the CNF was used as enhanced thermal conductivity additive. The Fourier transformation infrared spectroscope (FT–IR) and X-ray diffractometer (XRD) patterns indicate no chemical reactions took place among LA, PA, PVB and CNF. The SEM image shows the LA-PA eutectics and CNF were evenly distributed in the PVB. The thermogravimetric analyzer (TGA) results presents that the CPCM had no degradation at operating temperature (around 40 °C) and has good thermal stability. Thermal conductivity of CPCM2, 4, 5 and 6 (CNF mass ratio is 0, 1, 3and 5 wt%) is 0.18, 0.22, 0.28 and 0.40 W/(m⋅K), respectively. Latent heat of CPCM6 is 131.20 J/g, and its melting point is 34.07 °C.