Phase change materials (PCMs) are used in the field of thermal management because of their ability to absorb and release thermal energy through latent heat. However, the rigidity and leakage issues of PCMs limit their application in thermal management of electronic devices. In this paper, we prepared flexible phase change composites with excellent thermal management capabilities by mixing phase change microparticles with addition-cure liquid silicone rubber (ALSR). The prepared flexible phase change composites have superior mechanical properties, thermal cycling capacity, and temperature response rate, and the enthalpy can reach 156.1 J/g with a thermal conductivity of 0.84 W·m–1·K–1. The composites avoid the rapid warming by the solid–liquid transition of the PCMs, which can be applied to heat dissipation of laptop. To sum up, the prepared flexible phase change composites have excellent thermal properties and broad application prospects in the area of thermal management of electronic devices.
