【作者】 王林；

【导师】 周绍兵；

【作者基本信息】 西南交通大学 ， 材料学， 2014， 博士

【摘要】 随着科技的发展,人们对智能医用材料的要求越来越高,而传统的热致性形状记忆聚合物由于只能记忆一个温度,局限了其应用。最近几年研究较多的多刺激响应型、多功能的形状记忆聚合物能够更好的满足目前人们对形状记忆材料智能性的要求。本论文以生物相容性较好的聚氨酯、聚酯作为基体,设计并制备了多刺激响应型形状记忆聚合物、二重及三重形状记忆聚合物、温度记忆聚合物以及多功能型的形状记忆聚合物体系。并从结构、热力学、机理研究、细胞毒性等方面对各个材料进行了探讨。在论文第二章,我们设计并制备了侧链含有肉桂基团的光、热敏感多刺激型形状记忆聚氨酯体系。通过傅里叶转变红外光谱仪(FTIR)、核磁氢谱仪(’H-NMR)、紫外可见分光光度计(UV-vis)从结构上证实了材料的成功合成；通过差式量热扫描仪(DSC)、动态力学分析(DMA)结果,证实了材料具有较好的形状记忆性能；且通过调节体系中软硬段比例可以调节形状记忆聚氨酯的转变温度；最后通过对材料的光、热致形状记忆性能的研究发现材料具有较好的光致、热致形状固定率和形状回复率。在论文第三章,我们基于第二章带有肉桂基团的聚氨酯,进一步考察了光交联后的聚氨酯(TSMPU)的形状记忆性能。通过DSC、DMA等分析发现TSMPU具有两个明显的转变区域,一个区域归属于软段的熔融转变峰,另一个较宽的玻璃化转变温度范围归属于交联的硬段,这个特点具有与多重形状记忆聚合物相似的结构特点；因此我们通过DMA定量的考察了材料的三重热致形状记忆性能,结果证实TSMPU具有较好的三重形状记忆效应,并从结构上分析了材料的三重热致形状记忆机理；最后通过细胞毒性试验证实了材料具有良好的细胞无毒性。在论文第四章,我们探讨了聚乙烯醇(PVA)侧链接枝聚氨酯链段(PVA-PU)的水、热敏感多刺激型形状记忆性能。通过DSC、DMA、吸水性质等结果证实了PVA-PU具有较好的水致型、二重热致性形状记忆性能；且探讨了水致型形状记忆机理为：水分子的进入,起到了增塑作用,进而降低了材料的转变温度,属于间接型热致型形状记忆聚合物；通过对材料热力学及结构分析结果得到：在PVA-PU体系中聚氨酯内部的微相分离以及聚氨酯链段对PVA主链缠绕所形成的物理交联导致了PVA-PU具有一个较宽的转变温度范围；然后我们在这个宽的温度范围内选择了35℃和55℃作为研究材料三重形状记忆性能的转变温度,并通过DMA定量的对PVA-PU的三重形状记忆性能进行了考察,证实了材料具有较好的三重形状记忆效应；最后通过细胞实验证实了材料具有较好的细胞无毒性。在论文第五章,使用λ=365 nm紫外光对肉桂基团封端的星型PCL(4sPCL)和PEG进行光交联制备得到了一个具有温度记忆性能的c-4sPCL-PEG的交联网络结构。首先通过DSC、DMA、凝胶实验等结果确定了PCL分子量为4000,PCL与PEG质量比为1：1,交联时间为3h的条件下,c-4sPCL-PEG具有一个合适的交联度及较宽的温度转变范围；进而我们选择了37℃和45℃作为两个记忆温度对材料的温度记忆性能进行考察,结果表明材料在回复过程中,当达到这两个变形温度时材料具有最大即时回复速率,证实了材料良好的温度记忆性能；最后我们通过变温X-射线衍射、2D-FTIR对材料的温度记忆机理进行了探讨。在论文第六章,我们通过在聚酯(PIE)侧链中引入异烟酸基团,研究了金属配位聚合物的形状记忆性能。首先PIE与Ag离子进行配位得到Ag配位的聚酯(Ag-PIE),通过DMA结果证实了Ag-PIE的储能模量较PIE具有明显的提高,高的储能模量也证实了材料具有良好的热致性形状记忆性能；然后由于Ag离子的存在,进而通过涂布法和酶标法考察了材料的抗菌性能,结果显示材料具有良好的抗菌性能(抗菌率为89.3%)。通过电感耦合等离子体质谱(ICP)对Ag-PIE在37℃ PBS中释放情况进行了考察,发现经过24 h的释放,溶液中Ag离子浓度(0.91 ppm)远低于人体安全浓度(10 ppm)；最后通过细胞毒性实验也验证了材料具有良好的细胞无毒性。论文最后一章中我们制备了Cu配位的PIE(Cu-PIE),并初步考察了Cu-PIE的形状记忆性能和自修复性能。首先通过原子吸收光谱(AAS)和ICP比较了PIE分别与Ag离子和Cu离子配位情况,发现相同时间内,PIE在CuSO4中浸泡吸收的Cu离子比在AgNO3中浸泡吸收的Ag多,且在37℃PBS中释放24 h后释放量小；然后通过热重分析(TG)、DMA证实了Cu-PIE比Ag-PIE具有更好的热稳定性,且Cu-PIE的储能模量比Ag-PIE的高,证实了Cu-PIE具有良好的热致性形状记忆性能；最后通过切断法初步考察了Cu-PIE的自修复性能,证实了Cu-PIE在45℃下具有良好的自修复性能,并推测自修复主要机理为：由于配位键的存在,当材料置于分子链可流动的温度状态下,断面接触时,配位键在断面之间分子链运动的同时可以发生重新配位的作用,进而促使材料中分子链的重排,进一步促进分子链的缠绕,达到自修复的效果。更多还原

【Abstract】 With the development of science and technology, the application of conventional thermal-induced shape memory polymers (SMPs) is limited and in the face of the ever-increasing demands on the using of intelligent medical materials due to the fact that they can only remember one temporary shape. In recent years, the multi-stimuli sensitive and multi-functional shape memory polymers become a hot topic of intelligent materials due to they could meet the demands of intelligent for shape memory polymers.In this dissertation, polyurethane and polyester with well biocompatibility as polymeric matrix. We designed and prepared multi-stimuli sensitive SMPs, dual-and triple SMPs, temperature memory polymer and multi-functional SMPs. And we discussed all the intelligent polymers from their structure, thermodynamics, mechanism and cytotoxicity.Firstly, a system of photo-induced and thermal-induced shape memory polyurethane was prepared in chapter two. Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR) and ultraviolet-visible absorption spectrum (UV-Vis) confirmed the chemical structure of the polyurethane. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) results indicated that the polyurethane possessed good shape memory effect(SME), and the transition temperature of polyurethane could be adjusted to body temperature by alter the proportion of the soft and hard segments. Lastly, the polyurethane possessed good photo-induced and thermal-induced shape fixity ratio and shape recovery ratio by the investigation of the photo-and thermal-induced shape memory process.Based on the property of cinnamon groups of photo-induced shape memory polyurethane, we investigated the shape memory effect of photo cross-linked polyurethane (TSMPU) by 365 nm ultraviolet light in chapter three. DSC and DMA results indicated that the TSMPU possessed two transition temperature regions, one is owing to the melting transition of soft segments, and the other belongs to the glass transition temperature region of crosslinked hard segments. Then, we investigated the triple shape memory effect of TSMPU by DMA, and the results of DMA indicated that the crosslinked polymer showed good triple shape memory effect, and we analysed the triple shape memory mechanism from the structure of TSMPU. Lastly, Alamar blue assay showed that the polymer has good non-cytotoxicity and can be potentially used in biomaterial devices.Then, in chapter four we investigated the water-and thermal-induced shape memory effect of poly (vinyl akohol)-graft-polyurethane (PVA-PU). DSC, DMA and swelling experiments were carried out to find that the PVA-PU possessed good water-induced SME and thermal-induced SME, moreover, we studied the mechanism of the water-induced SME: the transition temperature of polymer decreased when it swelled in water, so the water-induced SMP is a kind of indirect thermal-induced SMPs. In addition, the results of thermodynamics and structure of PVA-PU indicated the polymer possessed a good triple shape memory effect, and 35℃ and 55℃ were selected for the transition temperature in the triple shape memory process. The DMA results indicated that the polymer possessed good triple SME. Lastly, the cell experiment confirmed that the polymer has good non-cytotoxicity.In chapter five, we synthesized a kind of star poly cross-linked star poly(ε-caprolactone)-poly(ethylene glycol) (c-4sPCL-PEG) with an excellent temperature memory effect (TME) by photo-crosslinking of cinnamon group terminated four arms poly(ε-caprolactone) (4sPCL-CA) and cinnamon group terminated poly(ethylene glycol) (PEG-CA) through the irradiation of 365 nm UV light. The results of DSC, DMA and swelling experiment confirmed the molecular weight of PCL, optimal proportion of PCL and PEG, the crosslinked time. Moreover, those results indicated that the c-PCL-PEG possessed a widely transition temperature and an appropriate crystalline. All the results indicated that the crosslinked polymer possessed a good TME. And then 37℃ and 45℃ were selected for the investigation of the TME. The DMA results showed that there is a maximum instantaneous strain recovery rate when it reaches the deformed temperature during the recovery process. Lastly, the mechanism of the TME was studied by X-ray diffractometry in different temperature and two-dimensional infrared correlation spectroscopy.Finally, we designed and prepared a polyester (PIE) containing isonicotinic group in chapter six. And the SME of metal coordination polymers was investigated. Firstly, Ag coordinated PIE was prepared, the results of DMA indicated that Ag-PIE possessed a larger storage modulus than PIE, and accounted for the good shape memory property of Ag-PIE. Then, the antibacterial properties of the Ag-PIE were investigated by coating method and ELIS A testing. The results indicated that the Ag-PIE possessed good antibacterial property, and the released amount of Ag ions in 37℃ phosphate buffer solution (PBS) was studied by inductivelycoupledplasmamassspectrometry (ICP), after the release of 24 h, the released amount of Ag ions is 0.91 ppm, and far below the safe concentration 10 ppm). Lastly, the cells experiment confirmed that the material has good non-cytotoxicity.In addition, the shape memory and self-healing properties of the cupper coordinated PIE (Cu-PIE) were investigated in the last chapter. The Cu-PIE showed that the more coordinated amount and less released amount than Ag-PIE in 37℃ PBS for 24 h from the results of Atomic absorption spectroscopy(AAS) and ICP. The Thermogravimetric analysis (TG) and DMA results indicated that the Cu-PIE had better thermal stability than Ag-PIE. Lastly, the self-healing property of Cu-PIE was studied by cutting-off method. The results indicated that the Cu-PIE with 5% water content emerged a good self-healing property at 45℃, and we analyzed the mechanism of the self-healing property through the molecular structure.更多还原