申请人:Bayer Aktiengesellschaft
公开号:US05008447A1
公开(公告)日:1991-04-16
This invention relates to a process for preparing polyurethanes having liquid crystal properties comprising reacting, in proportions corresponding to an NCO/OH equivalent ratio of from about 0.9:1 to 1.1:1, an organic polyhydroxyl compound with an organic diisocyanate having at least two phenylene groups and at least one carboxylic ester group. The organic diisocyanate comprises an aliphatic diisocyanate wherein at least one of the carboxylic ester groups connects an aliphatic group to a phenylene group or an aromatic diisocyanate wherein at least one of the carboxylic acid groups connects two phenylene groups. This invention further relates to preferred diisocyanates used in the process according to this invention.
本发明涉及一种制备具有液晶性能的聚氨酯的方法,包括按照NCO/OH当量比约为0.9:1至1.1:1的比例反应有机多羟基化合物和至少具有两个苯基和至少一个羧酸酯基的有机二异氰酸酯。所述有机二异氰酸酯包括至少一种脂肪族二异氰酸酯,其中至少一个羧酸酯基连接一个脂肪族基团和一个苯基或至少一个芳香族二异氰酸酯,其中至少一个羧酸酯基连接两个苯基。本发明还涉及用于本发明方法的优选二异氰酸酯。