Conformation of single poly(methyl methacrylate) chains in an ultra-thin film studied by scanning near-field optical microscopy
Conformation of single poly(methyl methacrylate) chains in an ultra-thin film studied by scanning near-field optical microscopy
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DOI：
10.1295/polymj.pj2007216
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发表时间：
2008-01-01
期刊：
影响因子：
2.8
通讯作者：
Ito, Shinzaburo
中科院分区：
文献类型：
--
作者：
Aoki, Hiroyuki;Morita, Sayuri;Ito, Shinzaburo
用扫描近场光学显微镜（SNOM）研究了聚甲基丙烯酸甲酯（PMMA）单链的构象。在这里，我们讨论的构象的聚甲基丙烯酸甲酯在有限的几何形状的薄膜厚度小于未扰动的链尺寸在散装状态。通过SNOM的直接观察进行分散在通过旋涂和Langmuir-Blodgett技术制备的未标记的PMMA的薄膜中的单个荧光标记的PMMA链。我们研究了高度方向上的约束对平行于膜表面的方向上的回转半径R-xy的影响，即，垂直于约束的链尺寸。在1-100 nm的厚度范围内，超薄膜中的R-xy与体相态中的R-xy没有显著改变，表明PMMA链在超薄膜中降低了链间缠结。
The conformation of a single poly(methyl methacrylate) (PMMA) chain was studied by scanning near-field optical microscopy (SNOM). Here we discuss the conformation of PMMA in the confined geometry of the thin film with a thickness less than the unperturbed chain dimension in the bulk state. The direct observation by SNOM was performed for individual fluorescence-labeled PMMA chains dispersed in the thin films of the unlabeled PMMA prepared by the spin coating and Langmuir-Blodgett techniques. We examined the effect of the constraint in the height direction on the radius of gyration in the direction parallel to the film surface, R-xy, i.e., the chain dimension normal to the confinement. In the thickness range of 1-100 nm, R-xy in an ultra-thin film was not significantly altered from that in the bulk state, indicating that the PMMA chain has lowered interchain entanglement in the ultra-thin film.