Bayer Aktiengesellschaft

Peter Heitk&auml;mper

Manfred Schmidt

Werner Rasshofer

Dirk Wegener

Holger Warth

Karsten Reihs

Klaus Jost

Joachim Wagner

Stefan Penninger

Eduard Mayer

Christian Wolfrum

Thomas M&uuml;nzmay

The present invention relates to polyurethane cast elastomers which are prepared from higher molecular weight polyhydroxy compounds, durene diisocyanate and low molecular weight chain-lengthening and/or crosslinking agents. These elastomers are particularly useful for the production of moldings exposed to high mechanical stresses.

Polyurethane cast elastomers based on durene diisocyanate

Durene diisocyanate is prepared by reacting durene with nitric acid in sulfuric acid, catalytic hydrogenation of the dinitrodurene that is formed, and phosgenation of the resultant durene diamine in a conventional manner. The intermediate products dinitrodurene and durene diamine do not have to be worked up in a complicated manner as solid products, but can be worked up in dissolved form. The intermediate products dinitrodurene and durene diamine do not have to be isolated and purified in a complicated manner. but can be processed directly after preparation. Another advantage of this process is that only a single organic solvent need be used for the overall preparation process. Separation and re-use of spent acid in the conversion of durene with nitric acid also renders the process of the present invention significantly less environmentally harmful than the known processes of the prior art.

Process for the preparation of durene diisocyanate

The present invention relates to composite materials made of at least one composite layer of a polyurethane and of a second composite layer which is directly bonded to the first layer and which consists of a thermoplastic material that is different from the polyurethane of layer A). The polyurethane material of layer A) is characterized by a residual content of free reaction components containing ether groups of no more than 400 ppm, and preferably of no more than 100 ppm. The invention also relates to a process for the production of these composite materials and to a method of their use as materials in motor vehicles.

Stable adhesive composite material made of polyurethane and of another thermoplastic material, a process for its production and a method for its use in motor vehicles

Growing community of inventors

Dormagen, Germany

Peter Heitkämper

Growing community of inventors

Dormagen, Germany

Peter Heitk&auml;mper

Peter Heitkämper