Patent · US Expired

Dewatering agent for sludge

US5525692A · kind A · utility

0Cited by
3References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 1994
Grant dateJun 11, 1996
Priority date
Expiry dateDec 28, 2014

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F2800/10
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A novel process for preparing an acrylic polymer containing a tertiary amino group which is not quaternized or not salt formed and having a high molecular weight, characterized by reacting an aqueous solution of an acrylic monomer containing a tertiary amino group with carbonic acid gas to generate an acrylic monomer containing a tertiary ammonium carbonate, homopolymerizing the obtained monomer or copolymerizing the obtained monomer with the other vinyl monomer copolymerizable with the obtained monomer to give a polymer containing a structural unit of a tertiary ammonium carbonate, and decarboxylating the polymer with heating and/or reducing the pressure is provided, and particularly, an article containing a water-soluble vinyl polymer which contains at least 5% by mole of the above-mentioned structural unit of a tertiary amino group and whose intrinsic viscosity [.eta.] is at least 1 dl/g is available as an excellent dewatering agent for sludge.

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