Fabrication and Characterization of Microencapsulated Phase Change Material with Large Diameter Range

Abstract

Microencapsulated n-octadecane with melamine-formaldehyde resin (MF) as shell was successfully fabricated by in-situ polymerization. Three kinds of emulsifiers, sodium dodecyl sulfate (SDS), styrene-maleic anhydride copolymer (TA) and sodium dodecylbenzene sulfonate (DBS) were used in the emulsification. The effects of pH values of the emulsion on morphology of microcapsules were investigated. In addition, the effects of diameters ranging from 5 to 200 µm of n-octadecane emulsion droplets and the microcapsules on crystallizing behavior were studied using Optical Microscope (OM) and Differential Scanning Calorimeter (DSC), respectively. The results indicated that the optimum microcapsules were synthesized with SDS under pH 3.0. The crystallization rates of liquid n-octadecane emulsion droplets and the microcapsules lowered with reducing its size regularly.

Keywords:

• Crystallization rate
• Emulsifier
• Microcapsule
• Phase change material

ACKNOWLEDGMENTS

The authors are thankful to the National Natural Science Foundation of China (No. 50573058) and Specialized Research Foundation for the Doctoral Program of Higher Education (No. 20050058004) for the financial support.

Notes

ΔH-average enthalpy of |ΔH_m| and |ΔH_c|; Measured PCM content-ratio of ΔH of MicroPCMs and that of corresponding n-octadecane bulk.