Heat-hardenable reaction resin mixtures comprising polyfunctional epoxide, polyisocyanate prepolymer and a reaction accelerator which is either a tertiary amine or an imidazole

US4562227A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Wolfgang Rogler · Erlangen, DE
• Helmut Markert · Nuremberg, DE
• Klaus Kretzschmar · Erlangen, DE
• Gerhard Piecha · Nuremberg, DE

Key dates

• Filing date: Jun 27, 1984
• Grant date: Dec 31, 1985
• Expiry date: Jun 27, 2004

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01B3/40
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The invention relates to heat-hardenable reaction resin mixtures which contain polyfunctional epoxides, polyfunctional isocyanates and a reaction accelerator as well as, optionally containing customary additives and/or fillers. The invention has the object of achieving reaction resin mixtures which are stable in storage, consist of individual components that are easy to mix, exhibit a prolonged prehardening period and permit at the same time the manufacture of materials which combine the good mechanical properties and the high temperature-cycle resistance of polyurethane structures with the good thermal properties of oxazolidinone and isocyanurate structures. According to the invention, the reaction resin mixtures contain as polyfunctional isocyanates, isocyanate prepolymerisates in the form of reaction products of diphenyl methanediisocyanate and a diol, or of an isocyanate mixture of diphenyl-methanediisocyanate and a polymethylenepolyphenylisocyanate (with a functionality greater than 2) and a diol. The prepolymerisates utilize 0.01 to 0.35 equivalents and preferably 0.05 to 0.2 equivalents of the diol per 1 equivalent of isocyanate; the mixture contains 0.2 to 5 equivalents iso…