| 摘要 |
It is known to use interfacial copolymerisation of an emulsion 1) whose disperse phase is a solution of a material and of a first monomer in a first solvent, and 2) whose dispersant is a solution of a second monomer in a hydrophobic solvent to form a membrane around the constituents of the disperse phase, where a) the first solvent is selected from water, hydrophilic solvents and mixtures thereof, b) the first monomer has low solubility in the hydrophobic solvent, and c) the second monomer has very high solubility in the hydrophobic solvent. The process gives stronger membranes if alpha ) the polymerisation is terminated by separating off the hydrophobic solvent, beta ) the capsules are re-suspended in a liquid in which i) the second monomer has very high solubility, and ii) the first monomer is less soluble than in the hydrophobic solvent, gamma ) a second portion of the second monomer is added to the suspension, delta ) the capsule membranes are reinforced by further polymerisation and rendered impermeable to the material to be encapsulated, and epsilon ) the polymerisation is terminated. the
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