高分子单链键接Fe_3O_4制备Janus复合纳米颗粒  

Single Polymer Chain Grafted Fe_3O_4 Composite Janus Nanoparticle

作　　者：井静云 姚晓辉 杨振忠[1,2] Jing-yun Jing;Xiao-hui Yao;Zhen-zhong Yang(State Key Laboratory of Polymer Physics and Chemistry,Institute of Chemistry,Chinese Academy of Sciences,Beo＇ing 100190;University of Chinese Academy of Sciences,Beijing 10004)

机构地区：[1]高分子物理与化学国家重点实验室中国科学院化学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《高分子学报》2018年第8期1066-1072,共7页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51233007;51622308)资助项目

摘　　要：采用溶剂热法制备油酸保护的Fe_3O_4纳米颗粒,通过硅烷配体交换在颗粒表面引入氨基.基于氨基快速淬灭阳离子活性种,将阳离子聚合制备的活性高分子链如聚(4-氯甲基苯乙烯)键接到氨基改性的Fe_3O_4纳米颗粒表面,制备高分子链/Fe_3O_4复合纳米颗粒.分子量决定键接活性高分子链数目.当高分子流体力学尺寸大于纳米颗粒直径时,空间排斥效应保证单根高分子链键接到Fe_3O_4纳米颗粒(10 nm),得到呈降落伞结构的复合Janus纳米颗粒,高分子链分布在Fe_3O_4颗粒一侧.当高分子链尺寸较小时,多根高分子链键接到纳米颗粒表面.研究了该复合Janus纳米颗粒双亲特性.作为固体乳化剂可容易乳化水/油体系得到稳定乳液.该Janus纳米颗粒在油水界面通过自组装可得到单层薄膜.An amine group capped Fe3O4 nanoparticle （NP） （- 10 nm） is derived after ligand exchange with a silane against the oleic acid capped Fe3O4 NP. Via the termination between the cationic end of a living polymer chain with the amine group onto the NP surface, polymer chains are covalently grafted onto the NP surface, forming the polymer/Fe3O4 composite NP. The number of the grafted living polymer chains is determined by the molecular weight of the polymer chains. When a sufficiently long polymer chain with hydrodynamic size larger than the NP diameter is used, the arisen steric repulsion enables only one polymer chain to graft onto the NP surface. The obtained composite NP displays a parachute structure due to the distribution of the grafting polymer chain on one side of the modified Fe3O4 NP surface. When a short polymer chain is used, many chains can graft onto the NP surface to form a core/shell like structure. For example, the single poly（4-vinylbenzyl chloride） chain grafted an amine group capped Fe3O4 composite Janus NP is amphiphilic, which can serve as a functional solid emulsifier that can easily emulsify water/toluene to obtain a stabilized emulsion. In analogy of a molecular surfactant, a self-assembled monolayer from the composite NPs is achieved by crosslinking the composite NPs at a water/oil interface. The Fe3O4 composite Janus NPs can be manipulated with a magnet. Accordingly, the stabilized emulsion droplets emulsified by the composite Janus NPs can be driven with a magnet. This report provides a simple method to massively synthesize Janus NPs at a high solid content. In addition, a huge family of functional Janus NPs will be derived after selective growth of functional species from either poly（4-vinylbenzyl chloride） or （and） the amine group capped side of the parent composite NP.

关 键 词：纳米颗粒 FE3O4 聚合物单链 JANUS 双亲性 

分 类 号：TB383.1[一般工业技术—材料科学与工程]