Occidental Chemical Corporation

David Y Tang

Byron R Cotter

Harry E Buckholtz

James J Maul

Mary K Cocoman

Viesturs Lesins

Mark E Lindrose

Arthur H Morth

William L Rueter

Frank P Bermel

Bao-Guo Huang

Frederick J Goetz

Michael J Fifolt

Bobby F Dannels

Michael C Hausladen

Sergio R Rojstaczer

Fredrick J Goetz

R Simon-Bierenbaum

John A Tyrell

Jerold C Rosenfeld

William S Derwin

Hang-Chang Bobby Chen

Jin-O Choi

Frederick J Goetz, Sr

Dean R Lagerwall

Karl W Seper

John Tyrell

James G Colson

Pravin M Khandare

Mark F Lechner

Viktor D Sorokin

Ernest W Ertley

Joseph F Bieron

Edward J Colman

Jerald C Rosenfeld

Disclosed is a method of separating the meta isomer of a haloalkylbenzene having the general formula

Reducing meta content of isomeric mixtures of halo substituted alkylbenzenes

Disclosed is a method of making high purity 2,4- and 3,4-dichlorotoluene from parachlorotoluene that contains some metachlorotoluene. About 0.0001 to about 5 wt % of a Friedel-Crafts catalyst and about 0.5 to about 10 equivalents of a brominating agent are added to the parachlorotoluene. The metachlorotoluene is brominated, but most of the parachlorotoluene is not brominated. Without separating the brominated products from the unbrominated products, about 0.5 to about 1.5 equivalents of a chlorinating agent are added, whereby only the unbrominated products (i.e., the parachlorotoluene) are chlorinated. The resulting 2,4-dichlorotoluene and 3,4-dichlorotoluene can be separated by distillation.

Method of making high purity 2,4- and 3,4-dichlorotoluene

Disclosed is a method of making an o-arylbenzonitrile by reacting o-chlorobenzonitrile with a substituted phenylzinc halide. The reaction is performed in the presence of a nickel catalyst, an ethereal solvent, and N-methylpyrrolidinone as a cosolvent.

Highly selective process for making o-arylbenzonitriles

Disclosed is a method of separating the meta isomer of a halotoluene having the general formula ##STR1## from a mixture with at least one other isomer, where X is Cl or Br. About 0.0001 to about 5 wt % of a Friedel-Crafts catalyst is added to the mixture and the mixture is exposed to a brominating agent which preferentially brominates the meta isomer. The mixture is then heated at a temperature above the boiling point of the other isomers but below the boiling point of the brominated meta isomer.

Reducing meta content of isomeric mixtures of halo substituted toluenes

Disclosed is a method of making a substituted diphenyldisulfide from a substituted thiophenol. A two phase reaction mixture is prepared which comprises a substituted thiophenol having the general formula ##STR1## hydrogen peroxide, water, an organic solvent, a basic salt that will give a pH between about 7 and about 10, and an optional flocculating agent. In the formula, R is selected from the group consisting of halogen, alkyl from C.sub.1 to C.sub.6, alkoxy from C.sub.1 to C.sub.6, or nitro. After the exothermic reaction is complete, the reaction mixture is cooled to crystallize the substituted diphenyldisulfide product. The symmetrical product precipitates preferentially over the unsymmetrical product, thereby enhancing the purity of the product over the purity of the starting material. Optionally, the organic solvent and the aqueous phase are recycled.

Method of making high purity substituted diphenyldisulfides

Disclosed is a blend capable of forming a semi-interpenetrating network when cured of (A) a solution of about 30 to about 50 wt % solids in an organic solvent of a fully imidized polyimidesiloxane and (B) about 5 to about 30 pbw per 100 pbw of the polyimidesiloxane of an epoxy resin which comprises a cycloaliphatic epoxy and an epoxy curing agent. The polyimidesiloxane is the reaction product of an aromatic dianhydride and diamine. The diamine is about 5 to about 80 mole % non-siloxane containing aromatic diamine and the remainder a siloxane diamine, where the siloxane diamine is about 40 to about 80 wt % of the weight of the polyimidesiloxane. The blend is used to bond metal parts to ceramic packages.

Adhesive sealant for bonding metal parts to ceramics

Disclosed is a method of making an o-arylbenzonitrile. A mixture is prepared of o-chlorobenzonitrile and about 1.0 to about 2.0 equivalents per equivalent of o-chlorobenzonitrile of a substituted phenylmagnesium halide in about 5 to about 30 mL per gram of o-chlorobenzonitrile of a solvent system of an ethereal solvent and N-methyl pyrrolidinone. The o-chlorobenzonitrile is reacted with the substituted phenylmagnesium halide at a temperature of about 10-.degree. to about 25.degree. C.

Process for making o-arylbenzonitriles

Disclosed is a process for making an aromatic nitrile by reacting a benzotrichloride with an ammonium halide in the presence of an oxygen-donating initiator at a temperature of about 150.degree. to about 250.degree. C. An optional catalyst of a metal oxide or a metal salt can be used if desired.

Process for making aromatic nitriles

Polyimidesiloxane solution and method of coating substrates

Halophthalic anhydrides are prepared by the liquid phase reaction of a brominating agent with halogen substituted hexa- or tetra-hydrophthalic anhydrides.

Process for the preparation of halophthalic anhydrides

A process for the preparation of a halophthalic anhydride, such as chlorophthalic anhydride, comprising the liquid phase reaction of bromine with a halogen substituted hexa- or tetra-hydrophthalic anhydride to produce halophthalic anhydride and gaseous HBr, and reacting the gaseous HBr with chlorine to regenerate bromine.

Disclosed is an aromatic diamine having the general formula ##STR1## where A is a group containing at least one aromatic ring, each Y is independently selected from ##STR2## R is a group containing at least one olefinically unsaturated group, R' is hydrogen, alkyl to C.sub.25, aryl, or R, n is 1 to 4, and the number of olefinic groups in Y is at least 3 when each Y is ##STR3## and otherwise is at least 2. Photosensitive polyamic acids and polyimides can be prepared from the aromatic diamines which can be crosslinked with light to a mask to form patterns on a substrate.

Diamines and photosensitive polyimides made therefrom

Halogen substituted aromatic compounds of the formula ##STR1## wherein Y is selected from the group CO.sub.2 H, COF, COCl, COBr, CF.sub.3, CN, NCO, or F, and X and X' are independently hydrogen or a halogen selected from the group F-, Cl- and Br-, at least one of X and X' being halogen; may be prepared by the liquid phase reaction of a brominating agent, at temperatures below about 190.degree. Celsius, with a correspondingly substituted cyclohexene or cyclohexadiene.

Aromatization process

A process for the preparation of 3-chloro-4,5-difluorobenzonitrile comprising the steps of

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East Amherst, NY, United States of America

David Y Tang