Patents Assigned to PRB N.V.
  • Patent number: 4391926
    Abstract: A soil stabilizer based on a prepolymer with terminal isocyanate groups, obtained by reaction of polyol with a stoichiometric excess of polyisocyanate, said prepolymer being such that in water a substantially stable dispersion of polyurea polymer particles is formed in the presence of a surface-active product.
    Type: Grant
    Filed: April 16, 1981
    Date of Patent: July 5, 1983
    Assignee: S.A. PRB n.v.
    Inventor: Hubert S. Creyf
  • Patent number: 4334944
    Abstract: The present invention provides a method to improve the rupture stability of polyurea foam materials to such a level that they can be applied on a commercial scale. This is achieved by incorporating 0.5 to 50 parts by weight of at least one alkanolamine having at least one amino group, one hydroxyl group and a molecular weight of from 47 to 2000 per 100 parts by weight of polyisocyanate used for the preparation of said polyurea foam materials. Preferably the foam material prepared is cut into pieces by cutting it in the rise direction, more particularly in the rise direction that is perpendicular to the machine direction of the foam, and subsequently crushing said pieces at least once.
    Type: Grant
    Filed: May 7, 1979
    Date of Patent: June 15, 1982
    Assignee: PRB N.V.
    Inventor: Hubert S. Creyf
  • Patent number: 4145362
    Abstract: A process for arylating an olefinic compound by addition of an aryl group to a double bond of said olefinic compound consisting in diazotizing an arylamine in an aqueous acidic solution comprising a lower alkanoic acid to form a solution of an aryldiazonium salt and reacting said aryldiazonium salt solution with an olefinic compound in an organic solvent in the presence of a catalytically effective amount of a copper halide.The amount of alkanoic acid is about 15 to 37% by volume of the total solvents used. The alkanoic acid is preferably acetic acid and the copper halide cuprous chloride.
    Type: Grant
    Filed: May 10, 1977
    Date of Patent: March 20, 1979
    Assignee: S.A. P R B en Neerlandais PRB N.V.
    Inventors: Joseph R. Brepoels, Jean-Marie Vaneghem