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:
Nov. 08, 1994
Filed:
Jan. 28, 1994
Mitsui Petrochemical Industries, Ltd., Tokyo, JP;
Abstract
Disclosed is a process for preparing cycloolefin random copolymer pellets, comprising adding an organic polar solvent to a solution of a copolymer obtained by copolymerizing ethylene and a specific cycloolefin and if desired an .alpha.-olefin other than ethylene, in an amount exceeding such an amount that the liquid mixture exhibits the cloud point, separating the copolymer solution utilizing phase separation phenomenon into a concentrated phase containing the cycloolefin random copolymer in a high concentration and a dilute phase containing said copolymer in a low concentration, feeding the obtained concentrated phase to an extruder where the solvents are removed and the copolymer is melted during extrusion processing, followed by pelletizing the copolymer. According to the invention, the steps for preparing cycloolefin random copolymer pellets can be reduced, and moreover, mold staining can De inhibited in the molding process of the resultant pellets because the pellets have low contents of the low molecular weight copolymer, the unreacted monomer, etc.