Process for foam production using dissolved under pressure carbon dioxide

US6127442A · kind A · utility

Assignees

• HENNECKE GMBH · DE
• BAYER HEALTHCARE LLC · DE

Inventors

• Hans-Michael Sulzbach · Rübhausen, DE
• Herbert Steilen · Rübhausen, DE
• Reiner Raffel · Siegburg, DE
• Robert Eiben · Lampertheim, DE
• Wilfried Ebeling · Neunburg vorm Wald, DE

Key dates

• Filing date: Dec 3, 1998
• Grant date: Oct 3, 2000
• Expiry date: Dec 3, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2375/04
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A process is described for the continuous production of polyurethane block foam using carbon dioxide which is physically dissolved under pressure as a foaming agent, wherein before the polyol and isocyanate components are mixed the carbon dioxide is dissolved in the polyol component and air or nitrogen is dissolved in the isocyanate component, both components are fed to a mixing chamber in which a pressure prevails which is 70 to 150% of the solution pressure of the CO.sub.2 in the polyol component, the isocyanate component is fed to the mixing chamber at a pressure of at least 30 bar and is injected therein with depressurization down to the mixing chamber pressure, wherein air or nitrogen in an amount of at least 1 g per kg CO.sub.2 is dissolved in the isocyanate component, and after emerging from the mixing chamber the mixture is depressurization to atmospheric pressure.