A method for the reduction of water in a Mud plaster and Gypsum slurry

摘要

Claim 1: a method for the reduction of water in a Gypsum Slurry, comprising: preparing a Gypsum slurry that includes water, Calcined gypsum, a Defoamer and a Dispersant, wherein the Dispersant is essentially a First and a Second Repeater units,Where the first Repeater unit is a Repeater Unit mono - unsaturated olefinic carboxylic acid or a Salt or an ester of the same, or Repeater Unit of olefinic unsaturated sulfuric acid or a Salt thereof,And the second Repeater unit has the General formula (1) wherein R1 is represented by the formula (2) and where R2 is Hydrogen or a Hydrocarbon C1 to C5 aliphatic Group, an aryl Group R3 is substituted or non substituted phenyl and preferably, and R4 is Hydrogen or a group hidrocarbu RO aliphatic C1 to C20 Hydrocarbon Group, a cicloalifu00e1tico C5 through C8,A C6 to C14 substituted aryl group or a group that follows the formula: (3): where R5 and R6, independently of each other, represent an alkyl group, an aryl, aralquilo alkylaryl and R6 is a group or alkyl, aryl, or alcarilo aralquilo divalent, p is 0, 1, 2, 3, M and N are even, in Independently, a whole number from 2, 3, 4, 5; X and y are independentlyIntegers from 1 to 350, including and Z is from 0 to 200, including a first portion of Retarder; add to the Mud, the first being a quantity of Retarder portion substantially enough to prevent the accumulation of Gypsum Crystals within the Mixer; add a Second A portion of the Retarder SludgeThe second portion of a Retarder amount sufficient to increase the Fluidity of slurry beyond that obtained by adding the first portion of retarder.