Process for preparing methylenedianiline and methylenebis...

Details Process for preparing methylenedianiline and methylenebis... Process for preparing methylenedianiline and methylenebis...

2007-06-12

2007-06-12

Oh, Taylor Victor (Department: 1625)

Organic compounds -- part of the class 532-570 series

Organic compounds

Isocyanate esters

C560S358000, C560S359000

Reexamination Certificate

active

10843046

ABSTRACT:
A process for preparing methylenedianiline by reacting aniline with formaldehyde in the presence of acid catalysts comprising, in a semicontinuous process, introducing aniline with or without acid catalyst, feeding formaldehyde with or without acid catalyst through a mixing element into a circuit in which aniline with or without acid catalyst and with or without previously added formaldehyde is circulated and, after feeding in at least 50% of the total amount of formaldehyde to be fed in, heating the reaction mixture to a temperature above 75° C.In addition, the invention relates to a process for preparing polyisocyanates by phosgenation of amines obtainable in this manner and to the polyisocyanates obtainable by this process.

REFERENCES:
patent: 3471543 (1969-10-01), Sayigh
patent: 4189354 (1980-02-01), Ellendt et al.
patent: 5053539 (1991-10-01), Yano et al.
patent: 5286760 (1994-02-01), Bolton et al.
patent: 6433219 (2002-08-01), Strofer et al.
patent: 2180285 (1996-12-01), None
patent: 2134756 (1971-07-01), None
patent: A 238042 (1986-08-01), None
patent: 295 628 (1991-11-01), None
patent: 0 451 442 (1991-10-01), None
patent: A451422 (1991-10-01), None
patent: A 751 118 (1997-01-01), None
patent: 1298258 (1972-11-01), None
patent: 1 378 423 (1974-12-01), None
patent: 1450632 (1976-09-01), None

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