| abstract |
A process is disclosed for preparing compact and preferably cellular polyurethane elastomers by reacting: (a) high-molecular polyhydroxyl compounds and optionally (b) low-molecular chain-lengthening and/or cross-linking agents with (c) 1,4-phenylene diisocyanate (p-PDI) and at least one additional aromatic diisocyanate selected from the group of toluylene-diisocyanate, diphenylmethane-diisocyanate, 3,3'dimethyl-diphenyl-diisocyanate, 1,2-diphenylethane-diisocyanate and/or an aliphatic diisocyanate with 4 to 12 carbon atoms and/or a cycloaliphatic diisocyanate with 6 to 18 carbon atoms, in the presence or absence of (d) catalysts; (e) foaming agents; and (f) additives. Components (a), (c) and optionally (c) are preferably reacted after their prepolymerisation. Also disclosed are isocyanate prepolymers suitable for preparing these elastomers. |