General Electric Company

Debjani Kapila

Ramesh Krishnamurti

Ashok Shyadligeri

Gary Charles Davis

Jan-Pleun Lens

Gurram Kishan

Edward Joseph Nesakumar

Veeraraghavan Srinivasan

Pramod Shankar Kumbhar

Vinod Kumar Rai

Umesh Krishna Hasyagar

Jegadeesh Thampi

Nileshkumar Prakash Kukalyekar

A S Radhakrishna

Radhakrishna Sreenivasarao Arakali

A process for forming a cycloalkylidene bisphenol comprises: reacting a cycloalkanone compound of formula:where [A] is a substituted or an unsubstituted aromatic group, R&#x2013;Rindependently represent a hydrogen or a C&#x2013;Chydrocarbyl group; and 'a' and 'b' are integers independently having values from 0&#x2013;3; with an aromatic hydroxy compound of formula [A]-OH, where [A] is as previously described; at a mole ratio of greater than or equal to about 20, in the presence of a sulfonic acid type ion exchange resin catalyst crosslinked with greater than or equal to about 8 weight percent of divinylbenzene, and a promoter selected from the group consisting of a mercaptan compound and a resorcinol compound; to form a cycloalkylidene bisphenol of formula:where [A], R&#x2013;R, &#x201c;a&#x201d; and &#x201c;b&#x201d; are as previously described. Moreover, any acid catalyst can be used with a resorcinol promoter.

Methods for preparing cycloalkylidene bisphenols

A method for purifying 1,1-bis(4&prime;-hydroxy-3&prime;-methylphenyl)cyclohexane comprises dissolving said 1,1-bis(4&prime;-hydroxy-3&prime;-methylphenyl)cyclohexane in a first solvent consisting essentially of an alcohol to form a first solution; filtering said first solution; adding a second solvent consisting essentially of water to the filtered first solution to form a second solution, wherein said second solution comprises about 40 parts to about 95 parts of the first solvent per 100 parts of the combined weight of the first and second solvents; crystallizing said 1,1-bis(4&prime;-hydroxy-3&prime;-methylphenyl) cyclohexane from said second solution to form a first crystalline product; dissolving said first crystalline product in a third solvent to form a third solution, wherein the third solvent comprises an aromatic compound; and crystallizing said 1,1-bis(4&prime;-hydroxy-3&prime;-methylphenyl)cyclohexane from said third solution to produce a second crystalline product.

Method for purifying 1,1-bis(4&prime;-hydroxy-3&prime;-methylphenyl)cyclohexane and methods of producing polycarbonates therefrom

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Debjani Kapila