Soil stabilizers and their preparation
AssigneeS.A. Prb
InventorHubert S. Creyf
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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.
Claims28
A soil stabilizer in the form of an aqueous composition which comprises water as a dispersion medium, a dispersed polyurea polymer, the polyol component of which consists of one or more polyols with hydrophobic and hydrophilic groups in a weight ratio between 30/70 and 90/10 and with an average molecular weight of 1500 to 6000 and a surface active product selected from the group consisting of:
- a compound of formula (I):
- ##STR5## wherein R is an alkyl group with 12 to 16 carbon atoms;
- or a linear or ramified hydrocarbon sulfonate, optionally containing ethoxy units;
- or a compound of formula (II):
- ##STR6## wherein R is an alkyl group with 12 to 16 carbon atoms and x+y=11, so that the average molecular weight is of the order of 700, said soil stabilizer being a stable, non-gel dispersion of particles of said polyurea polymer in said water.
A process for stabilizing soil, which comprises the steps of:
- mixing with water a surface active agent and a prepolymer wherein said prepolymer has terminal isocyanate groups obtained by reaction of a stoichiometric excess of polyisocyanate with a polyol, the polyol consisting of one or more polyols with hydrophobic and hydrophilic groups in a weight ratio between 30/70 and 90/10 and with an average molecular weight of 1500 to 6000, said prepolymer containing hydrophilic and hydrophobic units balanced such that the polyurea polymer formed in the water is water insoluble but forms a substantially stable dispersion in the presence of the surface active agent thereby forming a stable aqueous non-gel dispersion of said polymer and further wherein said surface active agent is selected from the group consisting of:
- a compound of formula (I):
- ##STR9## wherein R is an alkyl group with 12 to 16 carbon atoms;
- or a linear or ramified hydrocarbon sulfonate, optionally containing ethoxy units;
- or a compound of formula (II):
- ##STR10## wherein R is an alkyl group with 12 to 16 carbon atoms and X+Y=11, so that the average molecular weight is of the order of 700;
- and
- spreading said dispersion on soil.
Dependencies are inferred from the claim text.