摘要 |
Polyurethanes which have been prepared or combined with another material are made by combining or applying a polyurethane-forming reaction mixture or polyurethane to another material such as a PVC foil or textile. The polyurethane-forming mixture or polyurethane is made up of an organic polyisocyanate, a high molecular weight isocyanate reactive material, a catalyst and a stabilizer against thermolysis and contact discoloration. The required stabilizer is an epoxide having an epoxide equivalent weight between 57 and 10,000. Other additives commonly used in polyurethane chemistry such as blowing agents, chain extenders and surfactants may also be employed. The polyurethane composites thus produced are characterized by improved thermal stability and reduced discoloration.
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