Continuous production process of expandable styrene polymer beads

US5905096A · kind A · utility

Assignee

• BASF SE

Inventors

• Peter Nikolaus Lay · Ludwigshafen, DE
• Swen Ruck · Worms, DE
• Michael Schiessl · Altrip, DE
• Michael Witt · Ludwigshafen, DE
• Hans D. Zettler · Havelsee, DE
• Michael Baumgartel · Bischofswerda, DE
• Gerhard Dembek · Bad Dürkheim, DE
• Klaus Hahn · Lampertheim, DE
• Jan Holoch · Leimen, DE
• Wolfram Husemann · Neustadt, DE
• Knut Kaempfer

Key dates

• Filing date: Jan 29, 1998
• Grant date: May 18, 1999
• Expiry date: Jan 29, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08F12/08
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

A continuous process for preparing bead-form expandable styrene polymers in which the styrene is prepolymerized in bulk to a conversion of 10 to 80%, the prepolymer is dispersed in liquid form in an aqueous phase in the presence of suspension stabilizers, and the polymerization of the prepolymer is completed in an aqueous suspension to a residual styrene content of less than 2000 ppm.