A series of paraffin compounds, the phase change materials (PCMs), were microencapsulated
in an interfacial polymerization process to form the double-shell microcapsules
with relatively low shell permeability. The inner shell is formed through the reaction
between polypropylene glycols and bifunctional polyisocyanates and the outer through
the reaction between bifunctional polyisocyanates and polyamines added in the continuous
aqueous phase. The so prepared microencapsulated paraffin compounds emulsion can
be used as the medium for temperature management in many fields.