کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5191442 | 1381232 | 2005 | 7 صفحه PDF | دانلود رایگان |
The conformation of single polymer chain restricted in a two-dimensional plane was studied by scanning near-field optical microscopy (SNOM). The single dye-labeled chain in a monolayer of poly(isobutyl methacrylate) (PiBMA) with a high molecular weight of ca. 5Ã106 was directly observed by SNOM as a circular shape with a diameter of 200-300Â nm. The observed chain size was considerably smaller than that for a self-avoiding random walk chain generated by computer simulation, indicating that the polymer chain takes a contracted conformation in two dimensions. SNOM imaging was carried out for the labeled PiBMA chain dispersed in the matrix monolayer with 1000-times lower molecular weight. The long chain isolated among shorter chains had an expanded form as large as a random conformation. These results were in good agreement with the scaling theory, providing an unambiguous evidence for the first time with the real image for a single chain conformation by SNOM.
Journal: Polymer - Volume 46, Issue 16, 25 July 2005, Pages 5896-5902