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. 20, 1990
Filed:
Jun. 20, 1988
Norio Ogata, Sodegaura, JP;
Hiroyasu Yamato, Sodegaura, JP;
Idemitsu Petrochemical Company Limited, Tokyo, JP;
Abstract
Disclosed is a process for producing stably a polyarylene sulfide of high purity and high molecular weight by contacting a dihalogeno aromatic compound with an alkali metal sulfide in a polar solvent which comprises, as a first stage, reacting a dihalogeno aromatic compound with an alkali metal sulfide in a polar solvent in the presence of a lithium compound and in the presence of substantially no water at 200.degree.-270.degree. C. with concentration of remaining alkali metal sulfide being 5.5 g/l-polar solvent or less in terms of sulfur; then adding water in an amount of 1.0-10 mols per 1 mol of said alkali metal sulfide; and, thereafter, as a second stage, carrying out the reaction at 220.degree.-280.degree. C. Preferred dihalogeno aromatic compound is p-dichlorobenzene, preferred alkali metal sulfide is sodium sulfide and/or lithium sulfide and preferred lithium compound is lithium chloride and/or lithium sulfide.