Preparation of ethyl cellulose–glycerol tribenzoate microcapsules in CO₂/N₂‐switchable hydrophilicity solvent and solvent recycling

Abstract

In this article, a novel method of microcapsule preparation was provided, that is, ethyl cellulose-glycerol tribenzoate microcapsule (EGM) was prepared using CO 2 /N 2 switchable hydrophilicity solvent(N, N-dimethylcyclohexylamine) combined with an emulsion method. Microcapsules were prepared and solvents were recovered by changing the properties of the solvent. The optimum preparation conditions of EGM were the materials ratio of 20%, the oil-water ratio of 4.5:5.5, emulsifier content of 2%, the Span80-Tween80 ratio of 1:3, and the core-shell ratio of 1. The morphology of EGM is spherical, and the particle size can be adjusted from 0.01 μm to 90 μm by controlling the agitation speed in the synthesis process. Surprisingly, the average yield(Y[%]) reached 95.36%, the effective content(W[%]) reached 41%, and the encapsulation rate(E[%]) reached 90.66% of EGM. The solvent recovery rate(SR[%]) of the first recovered is 96.37%. Significantly, this method not only provides a new idea for the preparation of microcapsules but also expands the application field of switchable hydrophilicity solvents, which makes it has great potential application value in the field of microcapsule preparation in the future.