| 摘要 |
Process for recovering at least one polymer in solution in a solvent by precipitation by means of a non-solvent introduced gradually into the solution to form the precipitation medium, whereby: in the course of the introduction of the non-solvent into the precipitation medium, there is first a phase separation (into a continuous phase rich in solvent, in which the polymer is dissolved, and into a disperse phase, consisting of droplets rich in non-solvent) and then there is a phase inversion (the continuous phase then becoming the phase rich in non-solvent, and the disperse phase becoming the phase rich in solvent containing the dissolved polymer) the non-solvent is initially introduced into the precipitation medium in liquid form only and in a quantity (Q′) which is not zero but is less than the quantity (Q) required to bring about the phase inversion, and is subsequently introduced into the precipitation medium at least partly in vapour form.
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