| 摘要 |
<p>A novel process for the preparation of alcoholic compounds which contain hydroxyl groups and are suitable as the starting material for the isocyanate polyaddition process, by alcoholysis of polyisocyanate polyaddition products, in which A) polyurethane-urea or polyurea waste with a molar ratio between each urea group and urethane group of from 1:20 to 1:0 in comminuted form is heated with B) polyhydric alcohols having a molecular weight in the range of 62 to 250 while maintaining an A:B weight ratio of from 3:1 to 10:1, to 120 to 250 DEG C, subsequently removing at least 10 % of the polyhydric alcohol B employed by distillation under reduced pressure, a total of up to 1000 % by weight, based on the weight of A, of at least one polyhydroxide compound having a molecular weight of greater than 250 which is non-volatile under distillation conditions optionally being admixed with the mixture before and/or after the removal of the excess alcohol B by distillation, and use of the resultant hydroxyl-containing compounds as the starting material in the preparation of polyurethane plastics by the isocyanate polyaddition process.</p> |
