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:
May. 08, 1984
Filed:
Dec. 07, 1982
Hsueh M Li, Baton Rouge, LA (US);
Ethyl Corporation, Richmond, VA (US);
Abstract
Linear phosphonitrile chloride polymers are produced from linear phosphonitrilic chloride oligomers by means of a two-step proess. In the first step a mixture of linear phosphonitrilic chloride oligomer having an average degree of polymerization of at least 3 and preferably at least 4 is heated with an excess of ammonia or ammonium chloride having a relatively small particle size such that the Mean Value is within the range of from about 1 micron to about 110 microns. Cyclic phosphonitrilic chloride oligomer formed during the course of the first step is removed from the reaction mixture. After the removal of the cyclic oligomer the reaction mixture is subjected to the second step which involves heating the mixture in an inert liquid solvent (optionally in the presence of ammonia or ammonium chloride having a relatively small particle size) whereby the molecular weight of the linear phosphonitrilic chloride polymer is increased.