Method for the manufacture of low-melting polyurethanes having improved strength properties using a mixture of a polydiol having a molecular weight between 500 and 5,000 and a mixture of at least three diols

摘要

The invention described herein relates to a method for preparing a low-melting polyurethane which comprises the reaction of at least one diisocyanate, at least one polyol having a molecular weight between 500 and 5000, at least one diol which is branched or includes an ether group, and at least one diol which is unbranched. The diols have a molecular weight of less than about 500. The hydroxyl group content of the reaction mixture exceeds or equals the isocyanate content of the reaction mixture.