Patent · US Expired

Process for producing partially hydrolyzed acrylamide polymer

US4535131A · kind A · utility

8Cited by
3References
10Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 2, 1984
Grant dateAug 13, 1985
Priority date
Expiry dateApr 2, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F8/12
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Polyacrylamide in the form of aquagel is partially hydrolyzed in such a manner that small pieces of the aquagel are mixed with an alkali agent in a specified quantity and maintained at a temperature of 50.degree. to 95.degree. C. until the hydrolysis reaches substantial completion. The quantity of the alkali agent is that corresponding to 1/1.1 to 1/3 of the hydrolysis percentage desired of the final partially hydrolyzed polyacrylamide. The partially hydrolyzed polyacrylamide thus produced is characterized by uniform hydrolysis evidenced by its improved solubility in water and a pH around 7 of its aqueous solution. The term "aquagel" is herein used interchangeably with a term "hydrogel".

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.