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1. (WO2009129286) PROCESS FOR MAKING POLYAMINOPOLYPHENYL METHANES USING A MIXED SOLID ACID CATALYST SYSTEM

Pub. No.:    WO/2009/129286    International Application No.:    PCT/US2009/040622
Publication Date: Oct 22, 2009 International Filing Date: Apr 15, 2009
IPC: C08G 73/02
Applicants: DOW GLOBAL TECHNOLOGIES INC.
CHEN, Lao-Jer
JIMENEZ, Jorge
Inventors: CHEN, Lao-Jer
JIMENEZ, Jorge
Title: PROCESS FOR MAKING POLYAMINOPOLYPHENYL METHANES USING A MIXED SOLID ACID CATALYST SYSTEM
Abstract:
A method for preparing aromatic polyamines comprising (1) preparing a non-aqueous aminal solution; (2) contacting the non-aqueous aminal solution and an acidic siliceous catalyst to form a benzylamine intermediate; (3) contacting the benzylamine intermediate and an ion exchange resin catalyst based on a styrene-divinylbenzene copolymer to form an aromatic polyamine reaction mixture containing a polyaminopolyphenyl methane product; and (4) recovering the polyaminopolyphenyl methane product from the aromatic polyamine reaction mixture. The method, which may be practiced continuously, offers high 4,4'-methylene dianiline yield, reduced impurities, extended catalyst life, and, therefore, improved economics, when compared with many conventional methods to prepare polyaminopolyphenyl methanes.