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. 03, 1991
Filed:
Jan. 17, 1991
Ken Kashiwadate, Iwaki, JP;
Yoshikatsu Satake, Iwaki, JP;
Takashi Kaneko, Tokyo, JP;
Masahito Tada, Matsudo, JP;
Takayuki Katto, Iwaki, JP;
Kureha Kagaku Kogyo K.K., , JP;
Abstract
Disclosed herein is a process for the preparation of a poly(arylene thioether-ketone) improved in melt stability, which comprises subjecting a poly(arylene thioether-ketone) (PTK) to a heat treatment for 5-5.times.10.sup.3 minutes in a powdery state and a temperature range of 200.degree.-350.degree. C. The PTK has predominant recurring units of the formula ##STR1## and has a melting point, Tm of 310.degree.-380.degree. C., a melt crystallization temperature, Tmc (420.degree. C./10 min) of at least 210.degree. C., a residual melt crystallization enthalpy, .DELTA.Hmc (420.degree.C./10 min) of at least 10 J/g and a reduced viscosity of 0.2-2.0 dl/g. PTKs improved in melt stability and prepared in accordance with the above-described preparation process are also disclosed.