VERFAHREN ZUR HERSTELLUNG VON WAERMESTANDFESTEN POLYURETHANHARNSTOFF-ELASTOMEREN.

摘要

Polyurethane-urea elastomers are prepd. by a 1- or multi-stage conversion, free froms olvent, of (a) polyisocyanates, (b) higher mol. cpds. with NH2 or OH gps., opt. (c) low-mol. poly-OH cpds. or aromatic diamines as chain extenders, and (d) diaminodiphenylureas of formula (I) in powder form. reaction is in heterogeneous pahse, at temps. below the m.pt. of (d). Pre-polymers from (a) and (b) may replace these components. R1, R2, R3, R4 = H or 1-6C alkyl; and the NH2 gps. are in m- and/or p-position to the urea gp..