Process for preparing novel high solids non-aqueous polymer compositions
US5480921A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1994 |
| Grant date | Jan 2, 1996 |
| Priority date | — |
| Expiry date | Sep 1, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J3/09
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The use of falling-film evaporation and a concentration means such as centrifugal separation to dehydrate and concentrate a water-in-oil polymer emulsion or suspension is disclosed. In a preferred embodiment, a water-in-oil polymer composition containing less than about 25% active polymer solids is dehydrated in falling-film evaporator to produce an evaporator concentrate containing less than about 5.0% water. The evaporator concentrate then flows to a separation device such as a centrifuge, wherein oil is removed to produce a composition that is substantially a polymer and emulsifying surfactant-in-oil composition containing in excess of about 60 weight % polymer solids. The centrifuge raffinate may optionally be treated in a second separation means to capture additional polymer solids, with optional recycle of the oil-rich raffinate. The concentrated polymer composition is preferably stabilized with a steric stabilizer to produce a free flowing liquid product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.