Novel paraffin/ethylene propylene diene monomer phase change latex with excellent stability and low viscosity

Phase change latex (PCL) is a novel kind of phase change fluid with advantages both phase change emulsion (PCE) and latex. A series of oil/water PCLs were obtained by dissolving paraffin and ethylene propylene diene monomer (EPDM) in petroleum ether, followed by emulsifying in water. The effects of emulsifier type, emulsifier content, homogenization rate and paraffin content on stability, viscosity and particle size of PCL were systematically investigated. The results showed that paraffin/EPDM PCL was able to be stably stored when the content of emulsifier, a mixture of 1-dodecanesulphonic acid sodium salt (DAS) and sorbitan monooleate (Span-80), was 6 wt% and homogenization rate was 16000 r/min. Afterwords, the PCL with the paraffin mass fractions (paraffin to the sum of paraffin and EPDM) from 0 wt% to 100 wt% were prepared. When the paraffin content is 50 wt%, the PCL has the most excellent stability and suitable particle size and distribution. As the paraffin content increased, the viscosity of PCL generally decreased sharply, and the PCL enthalpy value increased gradually. PCL has great application potential in the field of thermal energy transmission in chemical pipelines and building homes.