Method for thickening aqueous systems
AssigneeRohm Co., Ltd.
InventorsHerbert Fink, Klaus Huebner, Gerhard Markert, Norbert Suetterlin
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Abstract
What is disclosed is a method for thickening aqueous systems in the acid range at a pH below 7 by the addition of an aqueous dispersion of a synthetic polymer having a molecular weight of at least 500,000, and which is water soluble or at least colloidally dispersible at a pH below 7, said polymer comprising (A) 5-100 percent by weight of at least one monomer having at least one basic nitrogen atom (B) 0-95 percent by weight of at least one monomer which has at most limited solubility in water, and (C) 0-30 percent by weight of at least one further non-basic, water soluble comonomer.
Claims15
The method of thickening an aqueous system, which method comprises mixing the aqueous system with an aqueous dispersion, different from said aqueous system, of particles of a synthetic copolymer, free of acid groups, comprising
- (A) 20-100 percent by weight of a basic unsaturated free radically polymerizable monomer having a pK.sub.b -value from 3 to 6 and at least one basic nitrogen atom,
- (B) 0-95 percent by weight of a neutral unsaturated free radically polymerizable comonomer which has at most limited solubility in water, and
- (C) 0-30 percent by weight of a neutral unsaturated free radically polymerizable comonomer which is water soluble,
- said polymer having a molecular weight of at least 500,000 and being water soluble at a pH value below 7, said mixture of the aqueous system and aqueous dispersion having a pH value below 7, whereby said copolymer is present therein in a dissolved state.
Dependencies are inferred from the claim text.