Step

One of many processes, such as the addition of a non-solvent for the polymer, is used to bring about coacervation-phase separation of the poly mer. This process promotes the formation of a new phase 'the coacervate' in a coacervation process. With stirring; coacervate droplets form which encapsulate the core to form microcapsules. It should be noted that most of the solvent used to dissolve the polymer is now the polymer-poor phase and forms the suspending medium in which the core and the coacervate droplets are stirred; this liquid is sometimes called the manufacturing phase. In the case of solvent removal, for example by evaporation, the polymer phase is enriched in polymer and it will eventually deposit on the core. In this system, because the solvent for the polymer has been removed, it may be necessary to provide another liquid, such as liquid paraffin or water which does not evaporate appreciably and is used to suspend the core and the polymer enriched phase.

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