| 摘要 |
<p>In the prodn. of (cellular) elastomer mouldings with a closed surface layer from polyurethane-polyurea elastomers based on organic polyisocyanates (I), di- or poly-ols (II) with mol. wt. 1800-12,000, aromatic di- or polyamines (III) as chain extender, catalysts for the reaction between OH and NCO gps. and opt. conventional blowing agent, auxiliaries and additives, the parent patent covers the use of active aromatic cpds., opt. with alkyl substits. in the o-position to the amino gps., and (III) and processing as one-shot system by the reactive casting technique. Improvement comprises the use of polyhdroxypolyester (IIa) with >=2 prim. OH gps. and (II) and/or a mixt. of the active (III) with =50 wt.% alkane-diols (IV) with 2 prim. OH gps. as chain extender. (IIa) can be used alone, instead of as opt. replacement for pt. of the polyhydroxy-polyether used previously and the compsn. has the same advantages as that in the parent patent.</p> |
