Polymeric thickeners for aqueous compositions

摘要

A process of preparing a concentrate which is useful as a thickener for aqueous compositions is provided. The process comprises obtaining a solution of an associative thickener compound in an organic solvent capable of forming a low boiling azeotrope with water. The solution is essentially free of water at this point and is at a temperature above the boiling point of said low boiling azeotrope. Water is added to said solution and an azeotrope of water and said organic solvent is distilled. The rate of addition of water is sufficient to replace said azeotrope with water, but is insufficient to cause a second phase to form in the resulting mixture of said solution and said water. The process yields a concentrate of an associative thickener in water, which concentrate is essentially free of volatile organic solvents.