Verfahren zur Rückgewinnung von festem mikroporösem Polyester aus einem Recyclingstrom und Produkte daraus

摘要

Process for recovering polyester polymer as a microporous solid from a mixed polymer recycle stream which comprises:- a) contacting the mixed polymer recycle stream at elevated temperature with a selective solvent in which polyester polymers are soluble and other polymers present in the recycle stream are substantially insoluble to form a solution of polyester polymer in the selective solvent; b) if the concentration of polyester in said solution is below 35 wt.%, increasing it to above that value; c) cooling the selective solvent solution to form a solid material having an interconnected phase of solid polymer domains rich in polyester polymer and a phase of solvent domains rich in selective solvent; d) extracting the selective solvent from the solid material to form a microporous solid. There is also provided an article comprising a molded, extruded, or cut, solid polyethylene terephthalate polymer having an open microporous structure, the average pore diameter being within the range of 0.5 to 50 microns.