聚氨酯／液晶复合膜的抗凝血性能研究

以聚醚型聚氨酯为基质材料，分别与向列型和胆甾型液晶化合物在适当溶剂中溶解共混后，利用溶剂发法在聚四氟乙烯板上浇铸成膜。研究了了复合膜中的液晶含量和成膜条件对复合膜表面结构形态的影响，同时详细研究了液晶含量对复合膜动态凝血性能、血小板粘附性能以及溶血性能的影响。研究结果表明，只有当复合膜中的液晶质量份数超过３０％时，复合膜才表现出良好的抗凝血性能，且液晶含量的增加而复合膜的抗凝血性能有明显的改善，尤其是复合膜表面吸附的血小板数量随液晶含量的增加而明显减少。

ANTICOAGULATION OF POLYURETHANE／LIQUID CRYSTAL COMPOSITE MEMBRANES

In our work, three series of polyurethane／liquid crystal composite membranes were prepared based on three different kinds of liquid crystal compounds［N-(4-methyoxybenzylidene)-4′-heptylaniline(MBHA), 4-pentyl-4′-nitrile-biphenyl(PNP) and cholesteryl oleyl carbonate(COC)］ by casting on polytetrafluoroethylene(PTFE) plates from a tetrahydrofuran(THF) solution of polymer and liquid crystal at room temperature. The result of this work shows that the content of liquid crystal in composite membrane must be more than 30 mass% in order to form liquid crystal phase on the composite membrane surface. The observation of platelet adhesion shows that the amount of platelets are adherent on the surface covered by the liquid crystal phase is fewer than that of pure polyurethane film when platelet-rich plasma is allowed to contact with the membranes for 1 h at room temperature. The determinant of dynamc blood clotting time and hemolysis ratio show that these polyurethane／liquid crystal composite membrances, in which the content of liquid crystal is more than 30%, appear to be beneficial in improving the anticoagulation.