| 摘要 |
<p>Disclosed is a process for providing an ultrapure article of manufacture, the process comprising: A) providing olefinic polymeric material containing impurities, B) subjecting the olefinic polymeric material to supercritical CO2 at a pressure of at least about 4000 psi (281.23 kg/cm2) at a temperature of from about 35 degrees Celsius and above, and wherein the olefinic polymeric material is subjected to the supercritical CO2 in a series of alternating periods of supercriticial CO2 flows and static periods of non CO2 flows but a supercritical CO2 environment to extract the impurities from the olefinic polymeric material and produce ultrapure olefinic polymeric material wherein the detectable level of impurities in the purified olefinic material is less than about 5 ppm, and C) molding an ultrapure article of manufacture from the ultrapure olefinic polymeric material and wherein the impurities does not reoccur.</p> |
