A Phase Change Material Nano-Emulsion for Cooling Applications

A nano-emulsion based on commercial PCM Rubitherm RT21HC has been successfully prepared in water with a concentration of 16 wt% and an average droplet size of less than 120 nm. Carbon Nanohorns have been incorporated into the dispersed phase as a nucleating agent. The nano-emulsion has been prepared in a batch of 200 mL with a solvent-assisted method and it has been characterized by DLS, Polarisation Intensity Differential Scattering, Rheometry, DSC, Thermoacoustic Thermal Diffusivity. Heat transfer capability has been tested with a Mettler Toledo EasyMax Synthesis Reactor. The system showed interesting stability and rheological properties; however, further work is needed to overcome some usual problems related to nano-confined systems, as the reduction of expected latent heat and PCM solidification supercooling. It can be estimated that this system shows an increase of apparent specific heat of about 8% with respect to pure water in a working temperature range of 18 degrees C.