| 摘要 |
<p>The recovering of a polyester polymer from a mixed polymer recycle stream (I), while maintaining the polyester polymer in polymer form, comprises: contacting (I) comprising 50 wt.% or more polyester polymer, lesser portions of other polymers, including polyolefins(s), and impurities, with a chemical wash solvent that dissolves portions(s) of the impurities and substantially rejects dissoln. of the polyester polymer present in the mixed polymer recycle stream, to form a chemical wash soln. contg. impurities dissolve din the chemical wash solvent, and a residual mixed polymer recycle stream (II); sepg. the chemical wash soln. from (II); contacting. at an elevated temp., (II) with a selective solvent that selectively dissolves the polyester polymer and substantially rejects dissoln. of any other polymer present in the mixed polymer recycle stream, to form a residual waste stream, a separate polyolefin phase, and a selective solvent soln. comprising the polyester polymer dissolved in the selective solvent; sepg. the selective soln. from the separate polyolefin phase, and from the residual waste stream; and pptg. the polyester polymer from the selective solvent soln., to form a pptd. polyester polymer and a spent selective solvent soln.; and sepg. the spent selective solvent from the pptd. polyester polymer, to obtain. a recovered polyester polymer having an intrinsic viscosity of 0.2-0.8 dl/g. Also claimed are methods for recovering a polyester polymer from a mixed polymer recycle stream.</p> |
