Manufacture of high molecular weight poly(vinylamines)
US4952656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 1989 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | Jul 12, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F8/12
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The inverse emulsion polymerization of a monomer of the formula ##STR1## wherein R and R.sup.1 represent hydrogen of a C.sub.1 -C.sub.4 alkyl group, using a surfactant system having a hydrophilic-lipophilic balance value from 4 to 9, an azo-type free radical initiator and certain hydrocarbon liquids to yield a water-in-oil emulsion of a homopolymer of at least 10.sup.6 average molecular weight, the emulsion having a viscosity less than 10 cps, at 15% solids, 60 rpm Brookfield and 20.degree. C. Also disclosed is the preparation of poly(vinylamines) of at least 10.sup.6 average molecular weight by acid or base hydrolysis of the homopolymer emulsion. Also disclosed are drilling mud compositions, cements for drilling holes, completion fluids, acidized fracturing fluids, and wet-end paper additives containing the poly(vinylamines) and demonstrating superior properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.