摘要 |
This invention relates to radiopaque polyurethane compositions which are reaction products of (a) cycloaliphatic diisocyanates; (b) at least one polyether diol having a molecular weight of from about 500 to about 6000; and (c) an isocyanate-reactive bromine-containing compound selected from the group consisting of (i) tetrabromodipentaerythritol and (ii) a mixture of tetrabromodipentaerythritol and dibromoneopentyl glycol; and (d) optionally, a catalyst; wherein the amount of component (c) is such that bromine constitutes at least 15% by weight of the polyurethane composition, wherein the weight ratio of component (b) to component (c) is from about 2:98 to about 55:45, and wherein the components are reacted at an isocyanate index of from about 95 to about 120.
|