A flexible method for changing the transition temperature of polyurethane solid–solid phase change materials

Transition temperature is significant in determining applications of phase change materials. In this paper, PEG2000 and PEG4000 were used as soft segments and MDI and 3,3ʹ-Dichloro-4,4ʹ-diaminodiphenylmethane (MOCA) were used as hard segments. Several polyurethane solid–solid phase change materials (PUSSPCMs) were synthesized by adjusting the mass ratio of PEG4000 and PEG2000. Based on the differential scanning calorimeter test, this paper studied the relationship between the mass ratio of PEG2000 and the phase transition temperature. The influence mechanism of phase change temperature was revealed from molecular structure, crystallization properties, and surface morphology. Furthermore, PUSSPCMs were tested for leakage and the thermal stability. The results showed that the synthesized PUSSPCMs had no liquid leakage during the heating process. There was a good linear relationship between the mass ratio of PEG2000 and phase transition temperature. The thermal decomposition onset temperature was above 230 °C.