| 摘要 |
The present invention is directed to a process for the production of optionally cellular, polyurethane elastomer moldings or optionally cellular, rigid structural polyurethanes by reacting a reaction mixture containing i) a polyisocyanate, ii) a high molecular weight polymer having at least two isocyanate-reactive groups and having a molecular weight of 400 to about 10,000, iii) about 5 to 50% by weight, based on the weight of component (ii) of a chain-extender having at least two isocyanate-reactive groups and iv) about 0.05 to 10 weight percent, based on the weight of components (ii) and (iii), of a salt based on a carboxy functional siloxane and an amidine group-containing compound of the formula <CHEM> wherein R1, R2 and R3 are straight or branched, saturated or unsaturated hydrocarbon chains having up to 30 carbon atoms which may optionally be substituted by ether groups, ester groups, amide groups or amidine groups and may optionally be terminated by isocyanate-reactive groups such as hydroxyl or amino groups, R4 corresponds to the definition of R1, R2 and R3, but may additionally represent an aromatic substituent having 6 to 15 carbon atoms or may represent the group -NR2R3 and R1, R2, R3 and R4 may, with one or both of the amidine nitrogen, also form a heterocyclic ring. The present invention is also directed to the amidine group-containing salt (iv) and to a isocyanate-reactive composition based on components (ii), (iii) and (iv). |
