Expandable olefin bead polymers

US6448300B1 · kind B1 · 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: Sep 26, 2000
• Grant date: Sep 10, 2002
• Expiry date: Sep 26, 2020

Classification

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

Abstract

The invention relates to expandable olefin bead polymers which comprise a blowing agent with a boiling point of from −5 to 150° C., selected from the group consisting of alkanes, alkanols, ketones, ethers and esters. The particles are unfoamed and have a bulk density above 500 g/l, and can be foamed to a bulk density below 200 g/l after storage for one hour at room temperature in free contact with the atmosphere. They are prepared by impregnating polyolefin pellets in suspension in a pressure vessel with the blowing agent, cooling the batch below 100° C., reducing the pressure and isolating the particles.