Method of manufacturing halogenated aromatic polysulfone compounds and the compounds so produced
US4996271A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 1988 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Dec 7, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G75/20
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Halogenation of Udel (trademark) and Radel (trademark) polysulfone occurs adily by electrophilic substitution. The reactive substitution position is situated ortho- to the aryl ether linkage in the Bisphenol-A portion of the repeat units. Halogenated polysulfones are obtained by reaction of the polymer with elemental halogen. Thus, a solution of Udel polysulfone in chloroform, treated with excess bromine at room temperature, gives dibrominated polysulfone III in high yield. The degree of substitution after 18-24 hours is typically 1.80 to 2.05 by bromine analysis. Similar results are obtained by reaction of the polymer with elemental chlorine. Lower degrees of substitution are obtained with shorter reaction times or using lesser amounts of halogen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.