响应性Janus材料的制备及其性能研究

发布时间：2018-12-17 08:27

【摘要】：随着社会的发展和科技的进步,新材料起到了至关重要的作用。而Janus材料因其不对称的结构和化学组成,具有独特的性质,近年来受到了科学界的广泛关注。但如何实现Janus材料更多的功能性和调控其化学组成是当前研究的重点与难点。本文将响应性聚合物引入到Janus材料中,赋予了Janus材料极大的功能性。主要工作内容如下:1.以氨基化的Si O2纳米粒子为模板,首先在其表面进行羟基功能化。利用模板表面的羟基,进行己内脂开环聚合,在模板表面形成疏水聚合物层,然后对聚己内脂(PCL)端基进行ATRP引发剂改性,引发p H响应性单体甲基丙烯酸二乙氨基酯(DEAEMA)和交联剂二甲基丙烯酸乙二醇酯(EGDMA)ATRP聚合,形成第二层具有p H响应性并具有交联结构的聚合物层。最后将Si O2模板刻蚀掉,就形成了内外层化学组成不对称的p H响应性聚合物基Janus中空球。可以通过p H值的变化,对外侧PDEAEMA聚合物层的表面浸润性以及中空球腔体体积进行调控。更重要的是,利用中空球Janus结构和环境响应性,可以实现对疏水药物DOX进行富集并可控释放。在本工作中,还测试了不同p H条件下的细胞对Janus中空球的内吞作用并对中空球的细胞毒性进行了测试和分析,证明了该结构的中空球在作为药物载体方面有一定的潜在应用。2.结合课题组前期的工作,通过乳液界面自组装,一步法批量制备Janus中空球。将Janus中空球机械磨碎即得到Janus纳米片。Janus纳米片的一侧是具有亲水性的氨基,另一侧具有硅羟基。氨基侧可以通过酰胺化反应在其表面改性ATRP引发剂,通过相应的ATRP聚合接枝具有温度响应性的PNIPAM聚合物,得到具有温度响应性的Janus复合纳米片并利用Na N3使ATRP端基失去再次引发聚合的能力。再将纳米片的硅羟基侧进行氨基表面改性并用酰胺化反应修饰ATRP引发剂,接枝具有p H响应性的PDEAEMA聚合物。通过两步分别在纳米片两侧的ATRP聚合,得到了具有温度/p H双重响应性有机/无机复合Janus纳米片。利用化学和物理的方法,成功标记了双重响应性纳米片的不同表面,证明了Janus纳米片的严格分区。在本工作中,通过改变水相中的温度和p H值,研究了Janus复合纳米片的双重响应性,并作为颗粒乳化剂用于稳定油/水乳液,同时利用Janus复合纳米片的双重响应性对乳液类型、稳定性进行调控。
[Abstract]:With the development of society and the progress of science and technology, new materials play a vital role. Because of its asymmetric structure and chemical composition, Janus materials have been widely concerned by the scientific community in recent years because of their unique properties. However, how to achieve more functionality and regulate the chemical composition of Janus materials is the focus and difficulty of current research. In this paper, the responsive polymer is introduced into the Janus material, which endows the Janus material with great functionality. The main work is as follows: 1. The surface of Si O 2 nanoparticles was firstly functionalized with amino groups as template. The hydrophobic polymer layer was formed on the template surface by ring-opening polymerization of hexanolipid using hydroxyl groups on the surface of the template. The (PCL) terminal group was modified by ATRP initiator. The p-H responsive monomer diethylamino methacrylate (DEAEMA) and the crosslinking agent dimethacrylate (EGDMA) ATRP) were polymerized to form a second layer with p-H responsiveness and cross-linking structure. Finally, the Si O 2 template was etched and a p-H responsive polymer based Janus hollow sphere with asymmetric chemical composition between the inner and outer layers was formed. The surface wettability of the outer PDEAEMA polymer layer and the volume of the hollow cavity can be regulated by the change of pH value. More importantly, it is possible to enrich and release hydrophobic drug DOX by using hollow sphere Janus structure and environmental responsiveness. In this work, we also tested the endocytosis of Janus hollow spheres under different pH conditions and the cytotoxicity of the hollow spheres. It is proved that the hollow spheres with this structure have some potential applications as drug carriers. 2. Janus hollow spheres were prepared by one-step batch method through self-assembly of emulsion interface. Janus nanoparticles were obtained by mechanical grinding of Janus hollow spheres. One side of Janus nanoparticles had hydrophilic amino groups and the other side had silica hydroxyl groups. The amino side can modify the ATRP initiator on its surface by amidation reaction, and graft the PNIPAM polymer with temperature response through the corresponding ATRP polymerization. Janus nanostructures with temperature response were obtained and Na N _ 3 was used to make ATRP terminal groups lose the ability to reinitiate polymerization. The silica hydroxyl side was modified by amino surface modification and amidation reaction was used to modify ATRP initiator. The PDEAEMA polymer with p-H response was grafted. By two steps of ATRP polymerization on both sides of the nanocrystals, the organic / inorganic composite Janus nanostructures with temperature / pH dual responsivity were obtained. Chemical and physical methods were used to label the different surfaces of the double responsive nanocrystals. It was proved that the Janus nanoparticles were strictly partitioned. In this work, the dual response of Janus composite nanoparticles was studied by changing the temperature and pH value of water phase, and used as a particle emulsifier to stabilize oil / water emulsion. Meanwhile, the dual response of Janus composite nanoparticles to emulsion type was studied. Stability is regulated.
【学位授予单位】：辽宁大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33

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