Patent ID: 6241828
Filing Date: 2001-06-05
Classification: B01D,C08C,C08J,Y02P

Abstract:
A method of removing impurities from an elastomer intended for medical or pharmaceuticals use, which methods comprises:performing a first solvent extraction process on the elastomer by contacting the elastomer with a first extracting solvent in a non-supercritical state to substantially remove impurities therfrom, therby leaving a residue of said extracting solvent in the elastomer; andthereafter subjecting the elastomer to a second solvent extraction process by contacting the elastomer with a second extracting solvent which is supercritical fluid or a mixture of a supercritical fluids, in order to remove or substantially reduce a concentration of said residue of said first extracting solvent remaining in the elastomer after said first solvent extraction process.