Method for producing a hard polyurethane-polyisocyanurate foamed material

US9718936B2 · kind B2 · utility

Assignee

• Covestro Deutschland AG · DE

Inventors

• Stephan Schleiermacher · Pulheim, DE
• Patrick Klasen · Vettweiß, DE
• Reinhard Albers · Leverkusen, DE
• Stephan Moers · Hückeswagen, DE
• Dirk Steinmeister · Leverkusen, DE
• Dieter Seidel
• Torsten Heinemann · Tarragona, ES
• Hans-Detlef Arntz · Overath, DE

Key dates

• Filing date: Feb 5, 2013
• Grant date: Aug 1, 2017
• Expiry date: Aug 17, 2033

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2375/08
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for producing a rigid polyurethane-polyisocyanurate foam C, comprising the step of reacting (i) an isocyanate-terminated prepolymer B with (ii) an activator component A comprising at least one trimerization catalyst A1 and at least one blowing agent A3 in a reaction mixture to form a foam, characterized in that—there is used an isocyanate-terminated prepolymer B obtained from a reaction of an isocyanate B1 having a mean isocyanate functionality of from ≧2.3 to ≦2.9 with a polyol component B2, and—the activator component A comprises water as the blowing agent A3 in an amount of from ≧5 wt. % to ≦50 wt. %,—the isocyanate index in the reaction mixture is in a range of from ≧400 to ≧500, and—the isocyanate content of the prepolymer B is in a range of from ≧21 wt. % to ≦30 wt. %, based on the total mass of the prepolymer B, and—wherein in the reaction of the prepolymer B and the activator component A a conversion contribution to polyisocyanurate of ≦75% is achieved. Rigid foams C so produced have good flame retarding properties while at the same time having good insulating properties and stability properties. The present invention relates furth…