The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 1977
Filed:
Jun. 13, 1975
Dae Suk Song, Wyckoff, NJ (US);
Richard Joseph Duffy, Greenwich, CT (US);
Charles Richard Witschonke, Noroton, CT (US);
Arthur Maurice Schiller, Stamford, CT (US);
Mark Allan Higgins, Gullford, CT (US);
American Cyanamid Company, Stamford, CT (US);
Abstract
A low molecular weight hydrolyzed polyacrylamide having exceptional effectiveness as a scale-inhibiting agent is prepared by a process involving simultaneously and continuously charging separate streams of acrylamide monomer, ammonium persulfate (as catalyst) and mercaptoalkanoic acid (as chain transfer agent) to a reaction zone containing water under reflux, the rate of charging being such that the heat of polymerization is sufficient to maintain reflux in the reaction zone without exceeding the capacity of the condenser to remove the heat of reaction, and then reacting the polymer product with sufficient aqueous caustic to hydrolyze from about 60 to 90% of the amide groups in the polymer product.