【作者】 王旭；

【导师】 沈家骢； 孙俊奇；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2012， 博士

【摘要】 层层组装是一种方便、灵活、可精确调控膜结构及组成的功能性膜材料的制备方法。利用层层组装技术制备的聚合物凝胶膜具有刺激响应性的离子交联结构及剩余的功能性作用位点，它能够可控地负载及释放客体材料，故其可用于功能性负载。另一方面，层层组装聚合物凝胶膜在长时间使用过程中，会不可避免的遭到损伤，从而导致其机械性能、保护作用或光学性质等方面的下降。层层组装聚合物凝胶膜的自修复将有效地延长其使用寿命，降低重新生产及维护所需的费用，并有效地提高材料的安全性。本论文以层层组装聚合物凝胶膜为研究体系，(1)开发了能够同时缓释正、负电荷分子的膜载体，并负载磁性纳米粒子在疏水的塑料介入导管材料表面制备了磁共振可见性增强涂层；(2)开拓了一种利用指数增长层层组装技术构筑自修复层层组装聚合物凝胶膜的方法，并探究了水引发的自修复层层组装聚合物凝胶膜对基底保护作用修复的机理；(3)利用水引发自修复体系及负载抗菌剂，制备了可完全修复其透明性的透明抗菌自修复涂层。在第一章中，介绍了功能性层层组装聚合物凝胶膜的研究现状及面临挑战。层层组装聚合物凝胶膜因其组成及结构高度可控而被广泛用作各种功能性涂层，如：抗菌涂层、超疏水涂层等等。在众多应用中，层层组装聚合物凝胶膜用于客体材料负载是研究的热点之一，然而它面临着很多挑战，如：能够同时缓释正、负电荷分子的载体膜材料的开发等等。另一个挑战则是具有自修复能力的层层组装聚合物凝胶膜的开发。因此，在本论文中我们设计并制备了具有负载及自修复功能的层层组装聚合物凝胶膜。在第二章中，我们以功能性聚合物微凝胶为构筑基元制备了能够同时缓释正、负电荷分子的膜载体，并利用负载有磁性纳米粒子的微凝胶在塑料表面制备了磁共振可见性增强涂层。在我们组之前的工作中，开发了一种具有大量功能性氨基并可以直接沉积在疏水材料表面的PAH-D微凝胶。在本章中，利用PAH-D微凝胶中的氨基与二氧化碳在碱性条件下进行反应，制备了一种聚两性微凝胶——PAH-D-CO2微凝胶。PAH-D-CO2微凝胶含有氨基和氨基甲酸基团，可以有效负载带正、负电的分子。PAH-D-CO2微凝胶可以与负聚电解质交替沉积成膜，所制备的聚两性微凝胶多层膜可以装载带正、负电荷的客体分子，并能够实现它们的同时缓释。我们还研究了利用阻隔层延长客体分子从膜内缓释周期的方法。此外，利用PAH-D微凝胶功能性的氨基，原位合成了磁性纳米粒子，制备了磁性微凝胶。磁性微凝胶与负聚电解质在疏水基底上交替沉积成膜，在塑料介入导管材料表面成功制备了磁共振可见性增强涂层，解决了塑料介入器具在磁共振成像中不可见的问题。在第三章中，我们以支化聚乙烯基亚胺及聚丙烯酸作为构筑基元，发展了一种指数增长层层组装技术制备本征型自修复聚合物凝胶膜的方法。该层层组装聚合物凝胶膜在空气中具有良好的机械强度，当将它浸泡在水中时，该膜具有好的流动性，聚合物链能够运动到受损部位，使受损部位再次接触；同时，膜内的功能性基团会通过超分子相互作用结合从而实现膜的修复。在本章中，我们还研究了该层层组装聚合物凝胶膜对基底保护作用的修复机理。在第四章中，我们结合层层组装聚合物凝胶膜的负载与自修复功能，制备了透明抗菌自修复层层组装聚合物凝胶膜。在本章中，我们通过调节层层组装膜的组装参数，成功制备了具有平整表面的透明层层组装聚合物凝胶膜，并利用表面活性剂胶束包覆法将疏水抗菌剂负载进入该透明层层组装聚合物凝胶膜，使其具备抗菌能力。如果当该透明抗菌层层组装聚合物凝胶膜的透明度因机械损伤而降低时，通过简单地将该膜浸泡在水中或向该膜喷水即可实现其透明度的完全自修复。该透明抗菌自修复层层组装聚合物凝胶膜将在触摸人机界面等领域具有潜在的应用。更多还原

【Abstract】 Layer-by-layer (LbL) assembly technique has been proven to be a versatile andconvenient way to construct functional films with precise control of film structure andcomposition. LbL assembled polymer hydrogel films with stimuli-responsive ioniccross-linked structures and free functional groups capable of loading and release of guestmaterials are widely studied as matrices for guest material delivery. On the other hand, theLbL assembled polymer hydrogel films will inevitably be damaged during daily use, leadingto a decrease of the film functions such as the mechanical properties, the protective properties,the optical properties and so forth. Self-healing of LbL assembled polymer hydrogel films canextend their service lives, reduce the costs of reproduction and maintenance, and enhance thereliability of functional films used in many applications. Based on the LbL assembled polymerhydrogel film systems, the researches in this dissertation include:(1) The development ofmatrix films for simultaneous release of anionic and cationic molecules, and the preparation ofmagnetic resonance visibility enhancing coatings on plastic surfaces.(2) The foundation of afacile exponential LbL assembly method for the rapid fabrication of intrinsic self-healing LbLassembled polymer hydrogel films, and the exploration of the water-enabled self-healingmechanism.(3) The fabrication of transparent antibacterial LbL assembled polymer hydrogelfilms capable of repairing their transmission properties based on the combine of the loading ofantibacterial agents and the water-enabled self-healing.In chapter1, introductions on the research actuality and the challenge of the functionalLbL assembled polymer hydrogel films have been provided. The LbL assembled polymerhydrogel films are widely studied as functional coatings, such as antibacterial coatings, superhydrophobic coatings, and so forth. Currently, more attentions have been paid on thefunctional loading of guest materials within the LbL assembled polymer hydrogel films.However, it still faces many challenges, such as the preparation of matrix films forsimultaneous release of anionic and cationic molecules, and the fabrication of LbL assembledpolymer hydrogel films capable of repairing themselves, etc. Therefore, the LbL assembledpolymer hydrogel films with functional loading and self-healing abilities were developed inthis dissertation.In chapter2, matrix films for simultaneous release of anionic and cationic molecules, andmagnetic resonance visibility enhancing coatings on plastic surfaces were fabricated by usingpolymer microgels as building blocks. In previous studies, chemically cross-linked PAH-Dmicrogels with abundant amine groups and substrate-independent modification capabilitywere developed. In this chapter, CO2gas was bubbled through PAH-D microgels to synthesizepolyampholyte microgels (named PAH-D-CO2). PAH-D-CO2microgels containing amine andcarbamate groups were LbL assembled with polyanion to produce polyampholyte microgelfilms. The as-prepared polyampholyte microgel films can realize the co-loading andsimultaneous release of anionic and cationic molecules. The releasing behaviors of thepolyampholyte microgel films can be tailored by capping the films with barrier layers. Besides,magnetic microgels were synthesized based on the functional amine groups in PAH-Dmicrogels. LbL assembled multilayer films of magnetic microgels and polyanion werefabricated on hydrophobic plastic surfaces to enhance the visibility of plastic interventiontools in MRI-guided therapy.In chapter3, a water-enabled self-healing method has been established by using theexponentially grown LbL assembled polymer hydrogel films as intrinsic self-healing coatings.The as-prepared self-healing coatings are mechanically stable under ambient conditions. Thecoatings become flowable in the presence of water, and polymer chains can therefore transferto the fractured areas, then the reversible supramolecular interactions accomplish the healing.The self-healing mechanism and the fundamental parameters governing the healing ability of the coatings are clarified.In chapter4, combining the loading and healing functions, self-healing for thetransmission properties of optically transparent antibacterial coatings here was simplyaccomplished by wetting the exponentially grown LbL assembled polyelectrolyte multilayersincorporated with antibacterial agents. Hydrophobic antibacterial agents were successfullyincorporated into the hydrophilic polyelectrolyte coatings via the encapsulation with surfactantmicelles. The transparent antibacterial coatings can effectively inhibit the growth ofgram-positive and gram-negative bacteria by the sustained release of antibacterial agents.Moreover, light transmittance of the damaged antibacterial coatings can be completelyrecovered by simply immersing the coatings in water or spraying water on the coatings, andthe coatings can realize the repeatable self-repairing in the same areas for both the surfaceappearances and the transmission properties of the transparent antibacterial coatings uponmultiple large abrasion events without the participation of healing agents. The transparentantibacterial coatings capable of repairing their transmission properties are expected as a kindof clean and durable protective materials applied in touch human-machine interface.更多还原