Preparation of polyurea microcapsules containing phase change materials in a rotating packed bed

Abstract

A series of polyurea (PUA) hollow microcapsules (HMCs) and microcapsules containing phase change materials (microPCMs) were synthesized with a rotating packed bed (RPB) via interfacial polymerization between isophorone diisocyanate (IPDI) and diethylenetriamine (DETA). Phase change materials (PCMs) were proved to be successfully encapsulated by a PUA shell with FT-IR spectroscopy. The morphologies and microstructures of the microcapsules were observed by optical microscopy and SEM, and the results showed that the morphologies of the microcapsules were all spherical geometries, and their surfaces were smooth and compact. The effect of the mass ratio of the core-to-monomer (C/M), emulsifier dosage and rotational speed (N) on the latent heat of the PUA microcapsules was investigated with DSC. Compared to a conventional stirring tank reactor, the RPB shows much better performance for encapsulating PCM via interfacial polymerization. The suggested C/M ratio, emulsifier dosage and N in our research conditions were 3 : 1, 0.5 wt% and 1200 rpm, respectively.