Patent ID: 7635785
Filing Date: 2009-12-22
Classification: C07F,C08K

Abstract:
1. A process for preparation of a dialkylphosphinic salt or a mixture of dialkylphosphinic salts comprising the steps of a) reacting, in a solvent system, at least one of hypophosphorous acid or a salt of hypophosphorous acid with at least one olefin in the presence of at least one free-radical initiator to give at least one of dialkylphosphinic acid or an alkali metal salt of dialkylphosphinic acid, and b) reacting the at least one of the dialkylphosphinic acid or the alkali metal salt of the dialkylphosphinic acid obtained in step a) with at least one of a metal or metal compound wherein the metal is selected from the group consisting of Mg, Ca, Al, Zn, Ti, Sn, Zr, and Fe, wherein the metal compound includes a metal selected from the group consisting of Mg, Ca, Al, Zn, Ti, Sn, Zr, and Fe to give at least one dialkylphosphinic salt of the metal, wherein the solvent system comprises at least one solvent system additive and water, wherein the solvent system comprises from 50 to 100% by weight of water and from 0 to 50% by weight of the at least one solvent system additive, wherein the at least one solvent system additive is selected from the group consisting of mineral acids, acidic salts, alkalis, and electrolytes, and wherein the mineral acids are selected from the group consisting of element-hydrogen acids, oxo acids, peroxo acids, and peroxo diacids of the elements of the seventh, sixth, fifth, fourth, or third main group of the periodic table.