Kelly Timothy L, Che Sara P Y, Yamada Yuri, Yano Kazuhisa, Wolf Michael O
Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada.
Langmuir. 2008 Sep 2;24(17):9809-15. doi: 10.1021/la8013688. Epub 2008 Jul 26.
A template approach to the synthesis of a series of conjugated polymer-mesoporous silica composite microspheres is described. Poly(3,4-ethylenedioxythiophene) (PEDOT), poly(thiophene), and poly( N-methylpyrrole) composites were prepared. The surface morphology of the samples was analyzed by scanning electron microscopy, and it was found that well-defined, monodisperse colloidal materials could only be prepared when the monomer is insoluble in the polymerization medium. The filling of the mesopores was systematically varied from 0% to 100%, and powder X-ray diffraction and nitrogen adsorption studies were used to confirm the pore filling. Thermogravimetric analysis shows that the polymer loading tracks the monomer loading in an asymptotic fashion. Conductivity measurements show that the conductivity of the PEDOT materials is relatively constant at high polymer loadings but decreases exponentially at low loadings. Measurements of the electrophoretic mobility were made in order to explain this behavior. These data suggest that, at high polymer loadings, the particle surface is characteristic of the polymer, while at low polymer loadings it is characteristic of the silica host. These results identify important design criteria for the template synthesis of a variety of new colloidal materials. Importantly, these optimized parameters may open the door to the preparation of colloids and colloidal crystals of previously unprocessable materials.
本文描述了一种合成一系列共轭聚合物-介孔二氧化硅复合微球的模板法。制备了聚（3,4-乙撑二氧噻吩）（PEDOT）、聚噻吩和聚N-甲基吡咯复合材料。通过扫描电子显微镜分析了样品的表面形态，发现只有当单体不溶于聚合介质时才能制备出轮廓清晰、单分散的胶体材料。介孔的填充率从0%到100%系统地变化，并用粉末X射线衍射和氮吸附研究来确认孔的填充情况。热重分析表明，聚合物负载量以渐近方式跟踪单体负载量。电导率测量表明，PEDOT材料在高聚合物负载量下电导率相对恒定，但在低负载量下呈指数下降。为了解释这种行为，进行了电泳迁移率测量。这些数据表明，在高聚合物负载量下，颗粒表面具有聚合物的特征，而在低聚合物负载量下，它具有二氧化硅主体的特征。这些结果确定了各种新型胶体材料模板合成的重要设计标准。重要的是，这些优化参数可能为制备以前无法加工的材料的胶体和胶体晶体打开大门。
