Method for producing polymer solutions
US11518695B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 2018 |
| Grant date | Dec 6, 2022 |
| Priority date | — |
| Expiry date | Aug 25, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2205/02
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method for producing an aqueous copolymer solution, which comprises dissolving a copolymer of (meth)acrylamide and at least 1 mol-% cationic monomers, calculated from total amount of monomers in the dissolving water having calcium hardness of at least mg/l, expressed as Ca2+, and adding acid comprising monoprotic organic acid and/or mineral acid to the dissolving water and/or the aqueous solution of the copolymer in an amount sufficient to provide the aqueous solution of the copolymer with a pH of equal to or less than 4.5. The invention also relates to uses of the obtained polymer solutions in manufacturing of paper, board or the like or in treatment of sludge or water.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.