Patent ID: 7846986

Claim:
A process for recovering at least one polymer in solution in a solvent which comprises consists essentially of precipitating by means of a non-solvent introduced gradually into the solution to form the precipitation medium, wherein: 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 the remaining quantity of non-solvent is subsequently introduced into the precipitation medium as a flow in which the vapor fraction is predominant, when a phase separation agent is used in the precipitation medium, the solution of polymer to be precipitated is substantially free of this phase separation agent at the time of phase inversion.