来自液晶型两亲性树枝状大分子的纳米杂化物。

Nanohybrids from liquid crystalline extended amphiphilic dendrimers.

作者信息

Cho Byoung-Ki, Jain Anurag, Mahajan Surbhi, Ow Hooisweng, Gruner Sol M, Wiesner Ulrich

机构信息

Department of Materials Science and Engineering, Cornell University, Ithaca New York, USA.

出版信息

J Am Chem Soc. 2004 Apr 7;126(13):4070-1. doi: 10.1021/ja0318986.

DOI:10.1021/ja0318986

PMID:15053572

Abstract

A novel extended amphiphilic dendrimer with linear poly(ethylene oxide) (PEO) attached to a PEO-like dendritic core as hydrophilic fraction and eight docosyl chain branches as hydrophobic fraction has been prepared for the use as structure-directing agent for silica-type materials. The extended dendrimer exhibits a hexagonal columnar liquid crystalline phase in the melt. Organically modified inorganic precursors and the extended dendrimer co-assemble into nanostructured hybrids. Hybrids with 0.44 weight fraction (fw) of aluminosilicate show a lamellar morphology, while hybrids with 0.21 fw exhibit a cylindrical structure. Nanostructures were characterized by a combination of small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The results suggest that dendrimer-based amphiphiles may provide an exciting platform for the formation of multifunctional organic-inorganic nanostructured hybrid materials with unique structural characteristics.

摘要

一种新型的扩展两亲性树枝状大分子已被制备出来，其具有连接到类聚环氧乙烷（PEO）树枝状核心上的线性聚环氧乙烷（PEO）作为亲水部分，以及八个二十二烷基链分支作为疏水部分，用作二氧化硅类材料的结构导向剂。这种扩展树枝状大分子在熔体中呈现六方柱状液晶相。有机改性的无机前驱体与扩展树枝状大分子共同组装成纳米结构杂化材料。含有0.44重量分数（fw）硅铝酸盐的杂化材料呈现层状形态，而含有0.21 fw的杂化材料则呈现圆柱状结构。通过小角X射线散射（SAXS）、透射电子显微镜（TEM）和原子力显微镜（AFM）相结合的方法对纳米结构进行了表征。结果表明，基于树枝状大分子的两亲物可能为形成具有独特结构特征的多功能有机 - 无机纳米结构杂化材料提供一个令人兴奋的平台。