The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 26, 2000
Filed:
Aug. 12, 1992
T Hwee Ng, Mississauga, CA;
Hadi K Mahabadi, Toronto, CA;
Man C Tam, Mississauga, CA;
Gregory J Kovacs, Mississauga, CA;
Eric M Peters, Waterloo, CA;
Rafik O Loutfy, Willowdale, CA;
Xerox Corporation, Stamford, CT (US);
Abstract
Disclosed is a process for preparing copolymers which comprises, in the order stated: (1) adding monomers containing unsaturated carbon-to-carbon bonds, a first polymerization initiator, a second polymerization initiator, and a solvent to a reaction vessel; (2) purging the resulting solution with an inert gas; (3) sealing the reaction vessel and pressurizing it by addition of an inert gas to a pressure of from about 20 to about 600 kilopascals over ambient atmospheric pressure; (4) maintaining the temperature within the pressurized reaction vessel at a temperature of from about 50 to about 100.degree. C. for a period of from about 60 to about 300 minutes; (5) thereafter maintaining the temperature within the pressurized reaction vessel at a temperature of from about 80 to about 115.degree. C. for a period of from about 30 to about 300 minutes, wherein the temperature in step (5) is higher than the temperature in step (4); and (6) subsequently maintaining the temperature within the pressurized reaction vessel at a temperature of from about 115 to about 160.degree. C. for a period of from about 30 to about 180 minutes, wherein the temperature in step (6) is higher than the temperature in step (5). Polymers prepared according to the process of the present invention can be particularly useful in migration imaging members.