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:
Mar. 18, 1997
Filed:
Jan. 04, 1996
Hideo Teshima, Kanno Sodegaura, JP;
Komei Yamasaki, Kamiizumi Sodegaura, JP;
Idemitsu Kosan Co., Ltd., Tokyo, JP;
Abstract
The present invention relates to a process for efficiently purifying a styrenic polymer which comprises adding a poor solvent alone or in combination with a swelling agent to a syndiotactic polystyrene produced by the use of a catalyst comprising (A) an aluminoxane or a coordination complex compound comprising a cation and an anion in which a plurality of radicals are bonded to a metal and (B) a transition metal compound, and treating the polystyrene under a controlled water content of 15 to 10,000 ppm to simultaneously carry out deactivation and deashing. The above process can efficiently remove residual metals without using a deashing agent and afford a highly pure high-grade crystalline styrenic polymer excellent in color tone.