Process for the manufacture of compositions of poly - poly isocyanate fenila kingdom by methylene bridge and compositions produced by said process.

摘要

1382452 Methylene bridged polyphenyl polyisocyanates IMPERIAL CHEMICAL INDUSTRIES Ltd 27 Dec 1972 [26 Jan 1972] 3681/72 Heading C2C In a process for the preparation of methylene bridged polyphenyl polyisocyanates by the phosgenation of methylene bridged polyphenyl polyamines, the methylene bridged polyphenyl polyamines used as starting material contain from 1 to 7% by weight of secondary amine expressed as weight per cent of aminobenzylaniline of the total methylene bridged polyphenyl polyamines. The methylene bridged polyphenyl polyamine containing 1 to 7% of secondary amine may be prepared by reacting aniline with formaldehyde.