Production of aromatic sulfide/ketone polymers with separation agent
US5089596A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1990 |
| Grant date | Feb 18, 1992 |
| Priority date | — |
| Expiry date | May 22, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G75/0281
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Aromatic sulfide/ketone polymer is prepared from dihaloaromatic ketone, alkali metal sulfide, water and a polar organic compound. The polymerization reaction mixture comprising the aromatic sulfide/ketone polymer is subjected to a heat soak at elevated temperature then a separation agent (non-solvent) is added under controlled conditions and subsequently cooled to provide a mixture comprising particulate aromatic sulfide/ketone polymer. Biaxially-oriented film is made from recovered particles of aromatic sulfide/ketone polymer prepared as described by (1) washing the polymer particles with an aqueous calcium salt, (2) heating said washed particles to remove water, wherein the resulting heated particles are at least partially crystalline, (3) molding said heating particles to form a sheet of polymer, (4) biaxially stretching said sheet above the glass transition temperature of the polymer to form a film, and (5) heat-setting said biazially-oriented film under stretching tension for a time and at a temperature to increase strength properties and density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.