General Electric Company

Howard J Klopfer

John Robert Campbell

Charles M Orlando

Tohru Takekoshi

Frank J Williams, Iii

John E Corn, Jr

Polyetherimides and their polyamic acid precursors are derived from bisphenol A dianhydride, or a mixture thereof with pyromellitic dianhydride, and bis(4-aminophenyl) sulfone or a mixture thereof with m-phenylenediamine and/or p-phenylenediamine. The polyetherimides are characterized by high thermal stability and solvent resistance.

Polyetherimides with high thermal stability and solvent resistance and

Asymmetrical bisphenols such as 2-(3-hydroxyphenyl)-2-(4-hydroxyphenyl)propane are prepared by an improved process wherein a hydroxyphenyldialkylcarbinol is reacted with a phenol in the presence of a hydrogen halide catalyst. According to the improved process, the carbinol is added to a mixture of the phenol and hydrogen halide under conditions maintaining a low carbinol concentration in the reaction mixture. This low concentration is preferably maintained by adding the carbinol in the form of a solution in a portion of the phenol.

Process for preparation of asymmetrical bisphenols

The preparation of hydroxyaryldialkylcarbinols by the reaction of hydroxyaryl alkyl ketones or alkyl hydroxyarenecarboxylates with Grignard reagents in a mixed ether-aromatic hydrocarbon solvent is frequently difficult on a large-scale basis because of formation of a voluminous precipitate of mixed magnesium salt. In an improvement in this process, a solution of the ketone or ester in an ether is added to the solution of the Grignard reagent.

Process for preparation of hydroxyaryldialkylcarbinols

A method is provided for enhancing the rate of formation of polyetherimides under melt or solution polymerization conditions by using either an alkali metal carboxylic acid salt, or a zinc carboxylic acid salt as a catalyst. The aforementioned catalysts are employed in a polymerization mixture of aromatic bis(ether anhydride) and an organic diamine.

Method for making polyetherimides using carboxylic acid salts of alkali

The compound 1,1,1-trichloro-2,2-bis(4-hydroxyphenyl)ethane can be prepared by effecting reaction between phenol and chloral in a solvent medium comprising aqueous sulfuric acid of a concentration of from 75 to 88%.

Preparation of 1,1,1-trichloro-2,2-bis(4-hydroxyphenyl)ethane

Diphenyl trichloro-ethanes can be prepared by effecting reaction between a phenol or anisole (methoxybenzene) with chloral in a solvent medium comprising sulfuric acid and a liquid aliphatic chlorohydrocarbon containing from 1 to 2 carbon atoms.

Process for preparing phenyl trichloro-ethanes

Certain impurities found in 9,9-bis(4-hydroxyphenyl)-fluorene are removed by treatment of the latter with a methanol-water mixture and thereafter isolating the purified fluorene.

Purification of crude 9,9-bis-(4-hydroxyphenyl)-fluorene

A method is provided for enhancing the rate of formation of polyetherimides by using either a sodium chloride catalyst, or ferric sulfate catalyst in a mixture of an aromatic bis(ether anhydride) and an organic diamine under melt polymerization conditions.

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Clifton Park, NY, United States of America

Howard J Klopfer