Development of High-Performance Polyurethane Biomaterials

由于嵌段液晶聚氨酯(LCPUE)具有液晶硬段，因此LCPUE有望在力学和生物医学性能方面表现出独特的行为。本研究的目的是探讨LCPUE在生物医学领域的适用性。1993年和1994.1两年的研究工作)制备了硬段由介元4，4‘-双(6-羟基己氧基)联苯和甲苯二异氰酸酯组成的液晶聚氨酯，软段由不同相对分子质量的聚四氢呋喃组成的软段。差示扫描量热法和广角X射线衍射法研究表明，LCPU在403K处的吸热与各向同性转变相对应。2)LCPU的表面结构分析由于生物材料已用于水环境中，因此发展了冷冻刻蚀X射线光电子能谱技术。这个TE…3)LCPUE表面热分子运动的评价利用X射线光电子能谱(XPS)和原子力显微镜(AFM)对其表面结构进行了研究。铸态LCPUE表面光滑平整，尺寸为纳米级。LCPUE在378K的热处理诱导了介晶硬段的有序化。LCPUE经PTMO(Mn=2000)处理后，表面粗糙度增加。采用扫描粘弹显微镜(SVM)研究了PTMO(mN=2000)对LCPUE表面相分离结构的影响。支持向量机分析表明，凹凸主要由橡胶状PTMO相组成。4)血浆蛋白与液晶的相互作用利用ATR-IR流动细胞技术和AFM研究了血浆蛋白与微相分离表面的相互作用。AFM结果表明，血浆蛋白在微相分离表面上发生了区域识别吸附。较少

Since segmented liquid crystalline polyurethanes (LCPUEs) have a liquid crystalline hard segment, LCPUEs expected to show a unique behavior in mechanical and biomedical performances. The purpose of this study is to investigate the applicability of LCPUEs for biomedical field. Following subjects have been studied in 1993 and 1994.1) Synthesis and characterization of LCPUESegmented liquid crystalline polyurethanes (LCPUEs) with the hard segments composed of the mesogen 4,4'-bis (6-hydroxyhexoxy) biphenyl and toluene diisocyanate (TDI), and the soft segments composed of poly (tetramethylene oxide) (PTMO) with various molecular weight have been prepared. Differential scanning calorimetric and wide angle X-ray diffraction study revealed that the endotherm at 403K corresponding to the isotropization transition.2) Surface structure analysis of LCPUESince biomaterials have been used in an aqueous environment, a freeze-etch X-ray photoelectron spectroscopic technique has been developed. This te … More chnique revealed the surface enrichment of hydrophilic component at the water-solid interface.3) Evaluation of surface thermal molecular motion of LCPUESurface structure of LCPUEs was studied on the basis of X-ray photoelectric spectroscopy (XPS), and the atomic force microscopy (AFM). As-cast LCPUE showed the smooth flat surface with nanometer scale. Annealing of LCPUE at 378K induced the ordering of mesogenic hard segment. Annealing of LCPUE with PTMO (Mn=2000) showed the increase in surface roughness. The scanning viscoelasticity microscopic (SVM) measurement was carried out in order to confirm the presence of phase-spparated structure on the surface of LCPUE with PTMO (Mn=2000). SVM revealed that bump was mainly composed of rubbery PTMO phase. This characteristic surface morphology was formed due to the ordering of hard segment being accompanied the increase in conformational entropy of PTMO segments.4) Interaction between plasma protein and LCPUEThe interactions between plasma protein and microphase-separated surface have been studied on the basis of ATR-IR flow cell technique and AFM.AFM results revealed the domain recognized adsorption of plasma protein. Less