PAMAM树枝状大分子基离子凝胶的制备与性能

发布时间：2018-06-28 22:18

本文选题：离子凝胶 + 自修复　；参考：《河北大学》2017年硕士论文

【摘要】：将离子凝胶替代传统的凝胶聚合物电解质应用于新型聚合物锂电池、柔性超级电容器等是目前国内外研究的热点。但是目前聚合物基体局限于含有结晶性的线形高分子均聚物/共聚物,离子迁移困难,且功能基团少,很难吸附更多的离子液体,离子电导率和力学强度不能满足在装配和使用过程中的要求。同时,目前的凝胶聚合物电解质在制造和反复使用中极易出现裂缝等结构缺陷,使用寿命很短。因此,如何实现离子凝胶同时具备良好的机械性能和高离子电导率,以及在制造或使用中受损后如何修复是目前离子凝胶电解质材料研究的关键问题。本文以具有无定型结构且官能团丰富的树枝状大分子聚酰胺胺(PAMAM)为基体,在离子液体中原位交联制备出具有特殊网络骨架和离子迁移通道的新型高性能离子凝胶,并对其自修复机制、导电性能、力学性能进行了详细的研究,揭示离子凝胶高离子电导率的微观机理及力学响应机制,同时研究了PAMAM/离子液体二元体系的相行为。所得结果如下:(1)采用希夫碱反应,以树枝状聚合物聚酰胺胺(PAMAM)为聚合物基体,离子液体作为溶剂和电解质,在离子液体中氨基原位交联,制备出一种具有动态共价键聚合物网络结构的高效自修复型离子凝胶。流变结果表明,离子凝胶的模量随着PAMAM含量的升高而升高,由于几何形状的影响随着PAMAM代数的增加有所降低,动态温度扫描结果表明,自修复型离子凝胶非常稳定,并且温度达到160 oC时这种可逆共价键网络结构仍然未被破坏。离子凝胶具有优异的导电性能,室温离子电导率能够达到10-2 S/cm。重要的是,在大量水的作用下,这种具有动态共价键聚合物网络结构的离子凝胶能够降解,并且其中的PAMAM和离子液体可回收利用。(2)采用Debus-Radziszewski反应,离子液体作为溶剂和电解质,制备出具有咪唑环交联结构的树枝状大分子聚酰胺胺(PAMAM)基离子凝胶。其室温离子电导率达6.8mS/cm,并且具有可调弹性模量104-106 Pa,动态温度扫描结果表明,离子凝胶在温度高达160 oC时仍处于稳定状态。将离子凝胶作为超级电容器中的柔性凝胶电解质,经测试具有较好的循环性能,比电容经5000次充放电后基本维持不变。(3)通过紫外可见分光光度计和光学显微镜研究了PAMAM/[BMIM][BF_4]体系相行为。结果表明,半代体系为相容体系,而整代体系发生了相分离。整代PAMAM/[BMIM][BF_4]体系呈现UCST行为,且临界共溶温度Tc随着PAMAM代数的增加而增大,对于PAMAM G1.0、PAMAM G3.0和PAMAM G5.0体系,临界共溶温度(Tc)分别为92、124和130 oC,临界浓度(Wc)均为10%。
[Abstract]:The application of ionic gel instead of traditional gel polymer electrolytes in new polymer lithium batteries and flexible supercapacitors is a hot topic at home and abroad. However, at present, the polymer matrix is confined to linear homopolymers / copolymers with crystallization, which makes it difficult to transfer ions, and has fewer functional groups, so it is difficult to adsorb more ionic liquids. Ionic conductivity and mechanical strength can not meet the requirements of assembly and application. At the same time, the current gel polymer electrolytes are prone to crack and other structural defects in manufacture and repeated use, and their service life is very short. Therefore, how to realize the ionic gel with good mechanical properties and high ionic conductivity, and how to repair the ionic gel electrolyte after being damaged in manufacture or use are the key issues in the research of ionic gel electrolyte materials. In this paper, a novel high performance ionic gel with special network skeleton and ion migration channel was prepared by in situ crosslinking of dendrimer polyamide amine (Pamam) with amorphous structure and abundant functional groups in ionic liquids. The mechanism of self-repair, conductivity and mechanical properties were studied in detail. The microscopic mechanism and mechanical response mechanism of ionic gel with high ionic conductivity were revealed. The phase behavior of PAMAM / ionic liquid binary system was also studied. The results are as follows: (1) in the presence of Schiff base reaction, dendrimer polyamide amine (PamAm) was used as polymer matrix, ionic liquid as solvent and electrolyte, and in situ crosslinking of amino groups in ionic liquids. An efficient self-repairable ionic gel with dynamic covalent polymer network structure was prepared. The rheological results show that the modulus of ionic gels increases with the increase of PamAm content, and decreases with the increase of PAMAM algebras due to the effect of geometric shape. The dynamic temperature scanning results show that the self-repairable ionic gels are very stable. And the reversible covalent bond network structure is not destroyed when the temperature reaches 160oC. The ionic gel has excellent conductivity, and the ionic conductivity can reach 10-2 S / cm at room temperature. It is important that the ionic gel with a dynamic covalent polymer network structure can be degraded under the action of a large amount of water, and that the PAMAM and ionic liquids are recyclable. (2) Debus-Radziszewski reaction is used, and ionic liquids are used as solvents and electrolytes. Dendrimer polyamide amine (PamAm) based ionic gel with imidazole ring crosslinking structure was prepared. The ionic conductivity is 6.8 Ms / cm at room temperature and has an adjustable elastic modulus of 104-106 Pa. the dynamic temperature scanning results show that the ionic gel is still stable at 160oC. The ionic gel is used as the flexible gel electrolyte in supercapacitor. (3) the phase behavior of Pamam / [BMIM] [BF4] system was studied by UV-Vis spectrophotometer and optical microscope. The results show that the half-generation system is a compatible system and the whole generation system is separated. The whole generation PAMAM / [BMIM] [BF4] system showed UCST behavior, and the critical co-dissolution temperature (Tc) increased with the increase of PamAM-algebra. For PAMAM G1.0 / PAMAM G3.0 and PamAM-G5.0 systems, the critical co-dissolution temperature (Tc) was 92124 and 130oC, and the critical concentration (WC) was 10oC.
【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O645.1;O648.17

【参考文献】