Patent ID: 6103774
Filing Date: 2000-08-15
Classification: C08G,C08J,Y02W

Abstract:
A process for removing contaminants, which comprises removing contaminants from a solid contaminant-containing polyester material at a temperature in the range of from 150.degree. C. to 250.degree. C. in the presence of an equilibrium amount of a gaseous polyester reversible side-production of ethylene glycol, said polyester material being solid throughout said process, wherein the molecular weight of the polyester is adjusted to a preselected molecular weight in the range of 0.5 to 1.2 I.V. by controlling the concentration of said gaseous ethylene glycol that is in contact with the polyester, and wherein said gaseous polyester reversible side-product of ethylene glycol is not a contaminant.