聚柠檬酸酯基可降解生物弹性体及其多孔支架的制备与表征

发布时间：2018-04-05 01:28

  本文选题：生物弹性体　切入点：柠檬酸　出处：《东华大学》2017年硕士论文

【摘要】：网络型聚酯生物弹性体,作为一类新型的生物医用材料,自身具有稳定的结构、优良的柔韧性、还有与人体软组织相匹配的模量等优点,目前已成为研究者关注的热点领域之一。而基于柠檬酸和二醇类化合物聚合形成的网络形聚柠檬酸酯类弹性体,由于其在组织工程支架材料和药物控制释放材料方面表现出良好应用前景,逐渐成为生物弹性体领域研究的热点之一。本文选择聚己内酯二醇为二醇单体,通过其与柠檬酸熔融缩聚得到聚(己内酯二醇-柠檬酸)(PCC)预聚体,进行热固化处理得到PCC生物弹性体;再通过将PCC弹性体与甲壳素纳米晶须复合,以改善弹性体的各方面性能;并利用盐析法制备弹性体多孔支架,以期用于组织工程领域。主要研究工作如下:1、通过熔融缩聚的方法制备PCC生物弹性体,并分别对反应投料比、后聚合的温度和时间进行探索。通过FT-IR、GPC、1H-NMR、DMA、DSC、TGA等测试方法分别对所制得的PCC弹性体的结构和性能进行表征,得出下列结论:柠檬酸和聚己内酯二醇发生了缩聚反应;通过调节单体摩尔比、后聚合的温度和时间,可以调节材料的力学性能、亲水性能和降解性能等;单体摩尔比为1:1时,在120℃、热固化7天得到的PCC弹性体综合性能最佳;材料具有pH响应性能,作为药物控释材料具有潜在的应用性。2、通过将PCC弹性体与甲壳素纳米晶须(CW)复合,以改善PCC弹性体的力学性能。采用FT-IR、DMA、TGA、XRD等方法对所制得的CW/PCC纳米复合弹性体结构和性能进行表征,得出以下结论:以丙酮为溶剂,PCC预聚体与CW能实现均匀混合,固化后可得到CW均匀分散于PCC中的纳米复合物;CW的引入,提高了PCC弹性体的亲水性,降低了其溶胀度以及降解速率,同时,明显增强了纳米复合物的拉伸强度和杨氏模量;此外,CW的引入还改善了PCC弹性体的细胞毒性。3、通过盐析法制备了PCC以及CW/PCC弹性体多孔支架,并进行了结构与性能表征,得出以下结论:当致孔剂NaCl的尺寸为400目、预聚体与致孔剂的质量比为1:6时,可以得到性能最佳的PCC弹性体多孔支架;基于PCC弹性体多孔支架的制备条件,制得的CW/PCC多孔支架具有良好的压缩回复性,随着CW含量的增加,多孔支架的力学性能也不断增大,最大的压缩强度达到345kPa;孔隙率在80%左右,吸水率约为105%,CW含量对多孔支架的吸水率及孔隙率影响不大。
[Abstract]:As a new type of biomedical material, the network-type polyester bio-elastomer has the advantages of stable structure, excellent flexibility, and modulus matching with human soft tissue, etc.At present, it has become one of the hot areas that researchers pay attention to.Based on the polymerization of citric acid and diol compounds, the netted polycitrate elastomer has a good application prospect in tissue engineering scaffold materials and drug controlled release materials.It has gradually become one of the hotspots in the field of biological elastomer.In this paper, polycaprolactone was chosen as the monomer of diol, and the prepolymer (caprolactone / citrate) was obtained by melt Polycondensation with citric acid, and the PCC bioelastomer was obtained by thermal curing.Then the PCC elastomer and chitin nano-whisker were combined to improve the properties of the elastomer and the porous scaffold was prepared by salting out method in order to be used in the field of tissue engineering.The main research work is as follows: 1. The PCC bioelastomer was prepared by melt Polycondensation, and the reaction material ratio, the temperature and time of post-polymerization were explored respectively.The structure and properties of the prepared PCC elastomer were characterized by FT-IR GPC-1H-NMR-DMA-DSC-TGA. The following conclusions were obtained: the condensation of citric acid and polycaprolactone, the temperature and time of post-polymerization by adjusting the molar ratio of monomers,The mechanical properties, hydrophilicity and degradability of the PCC elastomer can be adjusted, and the comprehensive properties of the PCC elastomer obtained at 120 鈩，

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