Kathleen B King

US Patent:

55164323, May 14, 1996

Filed:

Nov 21, 1994

Appl. No.:

8/342951

Inventors:

Kathleen J. King - Chalfont PA
William M. Hann - Gwynedd PA
Barry Weinstein - Dresher PA

Assignee:

Rohm and Haas Company - Philadelphia PA

International Classification:

C02F 512

US Classification:

210701

Abstract:

A process for stabilizing aqueous systems containing scale-forming salts by adding to such systems an effective amount of selected low molecular weight water-soluble polymers containing from 30 to 60 weight percent unsaturated sulfonic acid units, from 35 to 65 weight percent carboxylic acid units and optionally up to 10 weight percent of one or more units selected from non-ionizable monomers, is provided. The polymers used in the process provide improved phosphate and iron stabilization at high temperature conditions. A polymer composition based on 50/50 weight/weight 2-acrylamido-2-methyl-1-propanesulfonic acid/acrylic acid is particularly preferred for use at high temperatures, for example, from 80. degree. to 100. degree. C.