Okkema A Z, Grasel T G, Zdrahala R J, Solomon D D, Cooper S L
Material Science Program, University of Wisconsin, Madison 53706.
J Biomater Sci Polym Ed. 1989;1(1):43-62. doi: 10.1163/156856289x00055.
The bulk, surface, and blood-contacting properties of a series of polyether polyurethanes based on polyethylene oxide (PEO) (MW = 1450), polytetramethylene oxide (PTMO) (MW = 1000), and mixed PEO/PTMO soft segments were evaluated. The effect of varying the weight percentage of PEO, and thus the overall polarity of the mixed soft segment phase, was investigated. Two polymer blends prepared from a PTMO-based and a PEO-based polyurethane were also studied. Differential scanning calorimetry (DSC) and dynamic mechanical analysis indicated that the polyurethanes based on either the PEO or the PTMO soft segments are relatively phase mixed. The degree of phase mixing in the polymers increased with increasing weight fraction of PEO. As expected, water absorption and the hydrophilicity of the polymer increased with increasing PEO soft segment content. In vacuum, the PEO-rich polymers have a lower concentration of soft segment at the surface, possibly due to the migration of the polar PEO segments away from the polymer/vacuum interface. The blood-contacting results indicated that the higher PEO-containing polymers were more thrombogenic than the pure PTMO-based polyurethane. A threshold concentration of PEO in the polyurethane appeared to be required before the blood-contacting properties were significantly affected.
对一系列基于聚环氧乙烷（PEO，分子量 = 1450）、聚四氢呋喃（PTMO，分子量 = 1000）以及混合的 PEO/PTMO 软段的聚醚聚氨酯的本体、表面及血液接触性能进行了评估。研究了改变 PEO 的重量百分比从而改变混合软段相的整体极性所产生的影响。还研究了由基于 PTMO 的聚氨酯和基于 PEO 的聚氨酯制备的两种聚合物共混物。差示扫描量热法（DSC）和动态力学分析表明，基于 PEO 或 PTMO 软段的聚氨酯相对相混合。聚合物中的相混合程度随 PEO 重量分数的增加而增加。正如预期的那样，聚合物的吸水率和亲水性随 PEO 软段含量的增加而增加。在真空中，富含 PEO 的聚合物表面软段浓度较低，这可能是由于极性 PEO 链段从聚合物/真空界面迁移所致。血液接触结果表明，含 PEO 较高的聚合物比纯基于 PTMO 的聚氨酯更具血栓形成性。在血液接触性能受到显著影响之前聚氨酯中似乎需要有一个 PEO 的阈值浓度。
