【作者】 高军；

【导师】 刘炼；

【作者基本信息】 大连海事大学 ， 材料加工工程， 2008， 硕士

【摘要】 生物医用聚氨酯材料具有良好的机械性能、生物相容性、血液相容性和易加工等特点,被认为是最具有价值的医用合成材料之一。目前,可生物降解性聚氨酯材料在医学领域中最广泛的应用是作为药物控制体系的载体材料和体内短期植入物。当用这种材料作为载体的长效药物植入体内,在药物释放完之后不需要再经手术取出,可以直接在体内降解成为安全性物质从体内排除。因此,可生物降解聚氨酯材料的应用开发研究已经成为当前国际上的热门课题。本论文首先设计在不含扩链剂下,使用自己合成的双端羟基聚ε-己内酯（PCL）均聚物和聚ε-己内酯-聚乙二醇-聚ε-己内酯（19CL-PEG-PCL）三嵌段共聚物作为软段、1,6-己基二异氰酸酯（HDI）作为硬段合成了软段分子量不同的14种聚己内酯聚氨酯,红外光谱证明了3391cm^-1为N-H的伸缩振动峰,1738cm^-1为C=O羰基伸缩振动峰,1525cm^-1较弱的吸收带为N-H的弯曲振动峰,表明了酰胺键的存在。但是由于没有加入扩链剂,合成的聚氨酯均显示出较脆的特性,在生物医用方面的应用性不大。然后设计分别用7种扩链剂,使用不同分子量的PCL和PCL-PEG-PCL作为软段与硬段HDI反应合成了软硬段比例不同的聚己内酯聚氨酯。红外光谱同样证明了酰胺键的存在。力学测试表明PU2-7和PU2-5-1的拉伸强度分别为11MPa和9.5MPa,高于其他聚氨酯;PU2-3-1、PU2-4-1、PU4-2和PU4-3的断裂伸长率达到240%～270%。接触角测试结果说明相同软段时,随着扩链剂分子量的增加,接触角逐渐增加;相同扩链剂时,接触角与软段分子量和硬段浓度成正比。XRD测试结果表明,随着扩链剂分子量的增加,聚氨酯的结晶性逐渐降低。最后在pH=7.4汉克斯溶液,37℃的条件下,对PU2和PU4系列的聚氨酯进行了生物体外降解实验,结果表明:前40天,聚氨酯材料处于诱导期,水不断扩散到材料表面,降解缓慢,重量损失率（除PU2-7外）都小2%。40天以后,重量损失率均有所加快,但都小于3%。更多还原

【Abstract】 Biodegradable polyurethane materials have good mechanical properties, biocompatibility,blood compatibility,are taken as most valuable biomaterials in medical treatment.At present,biodegradable polyurethane materials are mainly applied to the repair and replacement of tissues ef human being,such as skin,manual blood vessel,bone and so on.They are most applied as carrier materials and body short term plants of medicine control system.When the medicine which uses these materials is planted to body,you don’t need to take out by surgery after medicine is released. These materials will become safe materials,and discharge from body.So the appliance of Biodegradable polyurethane materials has become current international hot discussion.A series of polyurethane materials were synthesized using either poly-ε-caprolactone（PCL）or triblock copolymer poly-ε-caprolactone-poly（ethylene glycol）-poly-ε-caprolactone（PCL-PEG-PCL）as the soft segment,1,6-hexamethylene diisocyanate（HDI）as the hard segment,using stannous octoate as catalyst,and several diols as chain extenders,which displayed a broad range of properties for the need of biomedical appliance.First,fourteen kinds of polycaprolactone-polyurethanes with different ratio of soft segments/hard segments were synthesized using different molecular weight of PCL or PCL-PEG-PCL as the soft segment,HDI as the hard segment,and without chain extenders.The absorption peaks of N-H at 3391cm^-1,1738cm^-1and 1525cm^-1in FTIR revealed polyurethanes were synthesized.But these polyurethanes were very crisp, couldn’t be applied broadly in biologic medical treatment without chain extenders. Second,polycaprolactone-polyurethanes with different ratio of soft segments/hard segments were synthesized using different molecular of PCL or PCL-PEG-PCL as the soft segment,HDI as the hard segment,and with seven chain extenders.FTIR revealed trevealed polyurethanes were synthesized.Mechanical test shows that the stress of PU2-7 and PU2-5-1 are 1 1MPa and 9.5MPa respectively,higher than others;The strain of PU2-3-1、PU2-4-1、PU4-2 and PU4-3 were 240%-270%.The drop-test showed that with the same soft segment,the angles were gradually increasing and then decreasing a little with molecular weight of chain extender increasing.With the same chain extender,the angles had direct ratio with molecular weight of soft segmens and concentration of hard segments.XRD showed crystallinity of polyurethanes decreaced with increasing of the molecular weight of the chain extenders.Last,the degradation behavior of two series of the polyurethane materials（PU2 and PU4）were investigated in Hanks（pH=7.4）at 37℃by examining changes in weight loss.The results showed that polyurethane materials degradated slowly,and their weight loss（except PU2-7）were only 2.5%in 40 days.After 40 days,the weight loss of polyurethane materials were improved,but no more than 3%.更多还原