Patent · US Expired

Process for preparing dry solid water absorbing polyacrylate resin

US4552938A · kind A · utility

45Cited by
6References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 25, 1982
Grant dateNov 12, 1985
Priority date
Expiry dateOct 25, 2002

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F220/06
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process is disclosed for preparing a solid, water absorbing, cross-linked polyacrylate resin including combining potassium acrylate and a polyvinyl monomer, such as N,N-methylene bisacrylamide, with water in an amount of 55 to 80 combined weight percent of potassium acrylate and polyvinyl monomer based on the total weight of potassium acrylate, polyvinyl monomer and water to form a monomer mixture, and adding a polymerization initiator to the monomer mixture to initiate polymerization of the monomer mixture. The monomer mixture then is polymerized without external heating by utilizing the exothermic heat of reaction as substantially the only non-ambient energy source to drive water away from said polyacrylate resin to form the cross-linked polyacrylate resin having a water content sufficiently low (i.e. 15% or less) to be powdered, such as by pulverization, without an intermediate drying step.

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