Research on morphological control and temperature regulation of phase change microcapsules with binary cores for electronics thermal management

Highlights: • The microcapsules with adjustable phase change temperature have developed. • The microcapsules morphologies can be controlled from spherical to spindle ones. • Microcapsules-s-graphene hybrid film is exploited for electronics thermal management. Phase change materials (PCM) has become one of the research hotspots for electronics thermal management owing to its high latent heat, low cost, simple structure, and other merits. In this study, a novel PCM with encapsulating binary paraffin cores and calcium carbonate shell has been proposed, the morphological control and temperature regulation strategies are investigated in detail. The apparent morphologies of resultant microcapsules could be controlled from spherical to spindle ones by comparatively high surfactant concentrations and reaction temperature. The DSC tests indicated the phase change temperature could be optionally adjusted within 20∼48 °C by the binary core ratio, phase change enthalpy can reach 103 J/g. TEM results showed the achieved microcapsules with typical core-shell structure about 1∼6 μm. In addition, the thermal conductive performance was greatly improved of 2.25∼2.63 times compared to the pristine paraffin, the main reason was not only the spindle morphology with superior heat transfer area but also the presence of conductive calcium carbonated shell. It should be noted that the microcapsules-graphene hybrid film developed by this work exhibited great thermal conductivity enhancement along with the appropriate temperature regulation and micro-size, exhibiting excellent prospect in the electronics thermal management and other energy storage fields.