Patent ID: 7569658

Claim:
A process for the solvent treatment of a plastic, comprising: (a) dissolving the plastic by contacting it with a solvent and with at least one phase separation agent (PSA) compatible with the solvent and capable of improving the dissolution of the plastic by the solvent so as to form a solution; (b) precipitating the plastic by contacting the solution with at least one non-solvent so as to obtain a solvent/non solvent mixture containing precipitated plastic particles; and (c) substantially eliminating the solvent from the mixture and recovering solid plastic particles, wherein after (a) but before (c), a stripping (d) takes place during which at least a substantial portion of the PSA is evaporated from the solution or from the mixture with a stripping composition comprising a stream of vapor which includes solvent in an amount sufficient to replace solvent evaporated from the solution or from the mixture during stripping and to keep the polymer concentration in the solution or in the mixture practically unaffected.