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:
Apr. 28, 1992
Filed:
Dec. 19, 1989
Manfred Bohshar, Kelkheim/Taunus, DE;
Hans-Jerg Kleiner, Kronberg/Taunus, DE;
Karl Waldmann, Bad Soden am Taunus, DE;
Gerhard Pfahler, Augsburg, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A process for the preparation of organophosphorus derivatives of 2,4-di-tert-butylphenol with a high proportion of organophosphorus derivatives of biphenyl, which comprises reacting, in a first step, a 4,4'-dihalobiphenyl whose halogen has an atomic weight of at least 35, under Grignard conditions with magnesium to form the corresponding Grignard compound and this is further reacted in a second step with bis(2,4-di-tert-butylphenyl) chlorophosphite with the formation of a mixture in which at least 50% by weight of the phosphorus is combined in the form of tetrakis(2,4-di-tert-butylphenyl) 4,4'-biphenylenediphosphonite. The invention further relates to a polyolefin molding composition containing tetrakis(2,4-di-tert-butylphenyl) 4,4'-biphenylenediphosphonite which was prepared by reaction of a 4,4'-dihalobiphenyl whose halogen has an atomic weight of at least 35 with magnesium to form the Grignard compound and by subsequent reaction with bis(2,4-di-tert-butylphenyl) chlorophosphite. The invention furthermore relates to a process for the preparation of 4,4'-dihalomagnesium compounds of biphenyl by reacting a 4,4'-dihalobiphenyl whose halogen has an atomic weight of at least 35 in the absence of an entrainer, with fine-particle magnesium which is held in suspension.