【作者】 刘同环；

【导师】 曾正志；

【作者基本信息】 兰州大学 ， 无机化学， 2009， 博士

【摘要】 本文合成了一系列具有pH和温度双重敏感的仿生材料-----聚（N，N-二乙基丙烯酰胺-co-甲基丙烯酸）P（DEA-co-MAA）及其水凝胶，用红外光谱、核磁共振谱和元素分析等对敏感性高分子及其水凝胶进行了表征；研究了pH值、温度、盐浓度对上述高分子水溶液低临界溶解温度（LCST）的影响；合成、表征了两种具有相似结构的苯甲酸衍生物与稀土及铜的配合物；研究了铜配合物与共聚物高分子之间的作用，探讨了其对高分子链段构象变化的影响；研究了共聚物水凝胶对药物的控制释放行为，主要研究工作如下：1．以甲基丙烯酸（MAA）和N，N-二乙基丙烯酰胺（DEA）分别作为pH敏感性单体和温度敏感性单体，采用自由基溶液聚合法，合成了几个系列的刺激响应性高分子材料P（DEA-co-MAA）；IR和¹³C NMR研究表明，共聚物由两种单体聚合而成。NaCl使共聚物高分子溶液的LCST迅速降低，溶液的透光率曲线急剧变陡。随着MAA含量的增加，共聚物高分子溶液的LCST缓慢增加；随着MAA含量继续增加，高分子溶液的LCST又出现降低；同时发现，共聚物高分子溶液的LCST随pH值的升高而升高。这种水溶性的双重敏感高分子共聚物材料，为药物控制释放提供了可以应用的载体。2．为了考查配合物与高分子的作用，合成了具有相似结构的模型化合物2-（4-甲氧苯氧基）-羰基-苯甲酸、2-（（4-甲氧）羰基）苯甲酸及其与Cu（Ⅱ）、La（Ⅲ），Eu（Ⅲ），Tb（Ⅲ）的配合物，通过单晶衍射、元素分析、HNMR、IR表征了它们的结构，证明配体以羧基和酯羰基氧原子与金属离子螯合配位形成配合物；所合成的两种Cu（Ⅱ）配合物均溶于水、甲醇、乙醇等质子型溶剂，因此，研究了它们对P（DEA-co-MAA）高分子溶液的LCST和高分子链构象的影响，发现随着配合物浓度的增加，高分子溶液的LCST逐渐降低，链直径增大，荧光强度降低，为探索金属配合物与生物大分子之间的相互作用提供了一种新的研究方法；对镧系元素配合物发光性能的研究表明配合物的固体荧光光谱分别显示Eu离子和Tb离子特征发射峰，为寻找高亮度和稳定的荧光材料提供了实验数据和信息。3．合成了具有温度和pH双重敏感性的共聚物高分子P（DEA-co-MAA）凝胶；实验表明，随着MAA含量增加，共聚物高分子P（DEA-co-MAA）凝胶的溶胀比出现了“增加—减小—增加”的趋势。这一结果说明，所合成的凝胶具有温度敏感性。L-色胺酸对P（DEA-co-MAA）凝胶的相互作用表明，L-色胺酸的固定得率、释放过程与共聚物的组成和pH值有密切的关系。对于三种具有不同取代基的磺胺药品研究发现，其在37℃时的释放曲线随着时间增加几乎没有变化，说明这种温敏性共聚物凝胶是磺胺药物的良好载体。4．合成了一系列P（DEA-co-MAA）聚合物的稀土配合物，通过元素分析、FT-IR以及TG-DTA对配合物进行了表征；同时对其与Eu（Ⅲ）和Tb（Ⅲ）配合物的荧光光谱进行了研究。发现高分子共聚物P（DEA-co-MAA）与Eu（Ⅲ）和Tb（Ⅲ）配合物的荧光强度与稀土和DEA的含量有关：金属离子的含量虽然很低时，DEA的含量相对较高，此时DEA把能量传递给中心离子，出现了随着稀土离子含量的减少，荧光强度变化并不明显的现象。更多还原

【Abstract】 In this paper, a series of pH-sensitive and temperature-responsive copolymers andhydrogels were prepared by free radical polymerization. The swelling behavior andpH sensitivity of the copolymers and hydrogels was studied in detail.1. A series of pH and temperature-responsive （N,N-diethylacrylamide-co-methylacrylicacid） copolymers were synthesized by radical copolymerization andcharacterized by elemental analysis, Fourier-transform infrared （FT-IR）, nuclearmagnetic resonance （NMR） ¹H, ¹³C and LLS. The effects of salt and pH on the phasetransition behaviors of the copolymers were investigated by UV. With increasingNaCl concentration, significant salt effects on their phase transition behaviors wereobserved. UV spectroscopic studies showed that the phase transition became fasterwith increasing NaCl concentration. The LCST values were found to increase slightlyinitially with increasing MAA content; further increase MAA content induced theLCST to decrease. In addition, the phase transition behaviors of copolymers weresensitive to pH. The pH and temperature sensitivity of these copolymers would makean interesting drug delivery system.2. 2-（（4-methoxyphenoxy） carbonyl） benzoic acid, 2-（1-methoxyvinyl） benzoic acidand their complexes LnL₂（OH）·3H₂O（Ln=La（Ⅲ）, Eu（Ⅲ）, Tb（Ⅲ）） andCu₂L₄（DMF）（CH₃OH）·CH₃OH, were synthesized and characterized by means ofelemental analysis, FTIR, ¹H NMR. And the Cu complexesdissolved in water, methol and ethanol, which give a support with the research of theantitumor activity in vitro. At the same time, the Cu complexes was added in thecopolymer solution, the result show that the LCST of the copolymer was decreasedwith the Cu complexes added, the DLS and fluorescence probe show that the chain ofthe copolymers were effected by the Cu complexes. All of this have a good begin toresearch the function between the Cu complexes and biopolymer. The luminescencespectra of Eu（Ⅲ） and Tb（Ⅲ） complexes in solid state were also studied. The strongluminescence emitting peaks at 615 nm for Eu（Ⅲ） complexes and 546 nm for Tb（Ⅲ） complexes can be observed, which could be attributed to the characteristic emissionsof Eu（Ⅲ） and Tb（Ⅲ） ions, this indicated that the ligands of HL^Ⅰand HL^Ⅱare goodorganic chromophore to absorb and transfer energy to metal ions. This providedexperimentations and information to find the steady and brightness luminescencematerials.3. In aqueous solution, a series of pH and temperature-responsive copolymerhydrogels were synthesized by radical copolymerization and characterized. The swellratio of the hydrogels was changed by the MAA content, pH and temperature. Andthen, the drug delivery system of the L-tryptophan in the drug-loaded hydrogelsshown that the process of the drug release was an complex course, which was affectedby pH and the composing of the copolymer. And the studies of the threesulfanilamides with different substitutes showed that there was no different in thereleased curve at 37℃. All of this showed that the copolymer hydrogels were auseableness carrier of drugs in the future.4. A series of complexes of poly（N,N-diethylacrylamide-co-methacrylic acid）（P（DEA-co-MAA）） with Ln（Ⅲ） （Ln = La, Eu, Tb） were synthesized andcharacterized by X-ray diffraction, elemental analysis, FT-IR and TG-DTA. Theluminescence spectra of Eu（Ⅲ） and Tb（Ⅲ） complexes in solid state were also studied.The complexes exhibit strong characteristic luminescence of Eu（Ⅲ） and Tb（Ⅲ） ions,while the luminescence intensity depend on the content of DEA and Ln（Ⅲ） ions: thechange of the relative luminescence intensity is not obvious when the lanthanide ioncontent is decreased.The possible reason is that more energy could transfer from DEAto Ln（Ⅲ） ions with the decrease of lanthanide ions content and the increase of DEAcontent.更多还原