Preparation of mixtures of brominated polystyrenes and brominated aromatic compounds

US4360455A · kind A · utility

Assignee

• BASF SE

Inventors

• Gerhard Lindenschmidt · Leimen, DE
• Wolfgang Schulte · Monheim, DE
• Franz Brandstetter · Neustadt, DE
• Herbert Naarmann · Wattenheim, DE
• Klaus Penzien · Bischofswerda, DE

Key dates

• Filing date: Jan 26, 1981
• Grant date: Nov 23, 1982
• Expiry date: Jan 26, 2001

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L55/02
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A mixture of brominated oligomeric polystyrenes, having a degree of polymerization of from 3 to 400, and low molecular weight brominated aromatic compounds of the diphenyl ether type is obtained by polymerizing the non-brominated starting materials, in a halohydrocarbon solvent, using a Lewis acid catalyst. The reaction mixture is then brominated and extracted with water to remove hydrogen bromide and catalyst, and the solvent and volatile constituents are separated from the product. The bromination is carried out at from -30.degree. C. to +130.degree. C. The final mixtures have a low melt viscosity and are therefore particularly suitable for incorporation, as a flameproofing agent, into thermoplastics.