Purification of impure scrap poly(ethylene terephthalate)
Abstract
Abstract A PROCESS FOR THE RECOVERY OF SUBSTANTIALLY PURE POLY(ETHYLENE TEREPHTHALATE) FROM SCRAP POLY)ETHYLENE TEREPHTHALATE) CONTAMINATED WITH IMPURITIES WHICH COMPRISES DISSOLVING THE CONTAMINATED POLY(ETHYLENE TEREPHTHALATE) AT ELEVATED TEMPERATURES AND UNDER SUPERATMOSPHERIC PRESSURE IN A VOLATILE SOLVENT IN WHICH SAID POLY(ETHYLENE TEREPHTHALATE) IS INSOLUBLE AT AMBIENT TEMPERATURES BUT SOLUBLE AT ELEVATED TEMPERATURES, SAID SOLVENT HAVING AN ATMOSPHERIC BOILING POINT OF ABOUT -104* C. TO 100*C. AND BEING ALIPHATIC ALCOHOLS OR MIXTURES THEREOF; FILTERING OFF IMPURITEIS; PRECIPITATING FINELY DIVIDED POLY(ETHYLENE TEREPHTHALATE) BY SLOWLY COOLING THE RESULTING SOLUTION WHILE MAINTAING THE SOLUTION UNDER SUPERATMOSPHERIC PRESSURE AND AT A SUBSTANTAILLY CONSTANT VOLUME; AND RECOVERING SAID SUBSTANTIALLY PURE POLY(ETHYLENE TEREPHTHALATE) BY A SECOND FILTRATION STEP.
Inventors
- 👤 Max F Meyer Jr
- 👤 Robert L Combs
- 👤 Willis C Wooten Jr
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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