Encapsulating Hydrophilic Solution by PU‐PMF Double‐Component Capsule Based on Water‐In‐Oil‐In‐Oil Emulsion Template

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/macp.201700418. ColloidsThis study demonstrates an effective method to encapsulate a hydrophilic payload through the use of polyurethane-poly(melamine-formaldehyde) (PU-PMF) dual-component capsules based upon the water-in-oil-in-oil (W/O/O) emulsion template. This emulsion has a middle oil layer that hosts the PU (outer shell) forming reaction while the internal PMF skeleton, fabricated concurrently by polymer precipitation in the aqueous dispersive phase, provides additional mechanical support. The resultant capsules exhibit dense and spherical shape, low permeability, and diameter of ≈50 µm. Remarkably, interfacial tension is the driving factor in the formation of the W/O/O template. This microencapsulation system and the methods used for its fabrication have a great technical potential for use in industrial applications.

Microencapsulation of Isocyanate in Biodegradable Poly(ε-caprolactone) Capsules and Application in Monocomponent Green Adhesives

“…A few works found in the literature report on the encapsulation of hydrophilic species by the solvent evaporation method; however, none of them are as highly reactive as isocyanate compounds. ,, , Tang reported on the encapsulation of a hydrophobic species, jojoba oil, using the solvent evaporation technique combined with a simple O/W emulsion system. For that purpose, two synthesized polymers were used, separately, as the MCs’ shell-forming material: cyclic poly­(phthalaldehyde) and poly­(vinyl tert -butyl carbonate sulfone).…”