4.
    发明专利
    未知

    公开(公告)号:BR8002600A

    公开(公告)日:1980-12-09

    申请号:BR8002600

    申请日:1980-04-28

    Applicant: BASF AG

    Abstract: A process for the preparation of an aryl mono-, di-, and/or polyurethane comprising the steps of A. reacting a primary aromatic mono-, di-, and/or polyamine with an O-alkyl carbamate in the presence of an alcohol at temperatures greater than 160 DEG C., and B. separating the ammonia and other by-products from the aryl mono-, di-, and/or polyurethane. The reaction is preferably carried out in the presence of urea. The aryl mono-, di-, and/or polyurethanes produced are valuable end and intermediate products. They can be transferred into the corresponding isocyanates which can then be used for the preparation of polyurethanes.

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