Preparation of expandable propylene polymer beads

US6727291B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Christian Maletzko · Altrip, DE
• Klaus Hahn · Lampertheim, DE
• Isidor de Grave · Monsheim, DE
• Gerd Ehrmann · Deidesheim, DE
• Franz-Josef Dietzen · Haßloch, DE

Key dates

• Filing date: Nov 5, 2001
• Grant date: Apr 27, 2004
• Expiry date: Jan 16, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2323/10
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A process prepares expandable propylene polymer beads by mixing propylene polymer melt with a volatile organic blowing agent and with a nucleating agent in an extruder, whereupon the extrusion and pelletization of the extruded takes place in a water bath under conditions of temperature and pressure at which practically no foaming of the pellets takes place.