Hydrophobically associating polymers containing dimethyl acrylamide functionality
US4997878A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1990 |
| Grant date | Mar 5, 1991 |
| Priority date | — |
| Expiry date | Jun 28, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F220/56
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention describes novel hydrophobically associating ter or tetra polymers which can contain sulfonate functionality which are useful as aqueous fluid rheology or flow modifiers. These high molecular weight water soluble polymers contain both water soluble and water insoluble monomers. The water soluble monomers are N, N dimethylacrylamide acrylamide (DMA) and optionally a salt of an ethylenically unsaturated sulfonic acid (s) or N-vinylpyrrolidinone or a metal acrylate and the water insoluble monomer is a higher alkyl acrylamide (R). The process for their preparation relies on solubilizing the water insoluble monomer into an aqueous micellar solution containing one or more surfactants and the water soluble monomers. The surfactants are specifically selected to enable homogeneous dispersion of the hydrophobic monomer(s) in the presence of anionic sulfonate containing monomers. Redox or free radical initiators are used to compolymerize both the water soluble and water insoluble monomers, forming terpolymers of dimethylacrylamide, alkylacrylamides and acrylamide, and optionally an anionic sulfonate or carboxylate monomer. Aqueous solutions of these hydrophobically associating p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.