title: Stiffness- and conformation-dependent polymer wrapping onto single-walled carbon nanotubes.
abstract: This work reports the effect of stiffness and conformation of chain-like polymers on wrapping behaviors around single-walled carbon nanotubes (SWNT). As a model of chain-like polymers, three kinds of poly(dialkylsilane) (PSi)s with random-coiled, flexible, and semiflexible main chains were employed. Complexes of PSi and SWNT were prepared using mechanochemical high-speed vibration milling (HSVM). Stiffness-dependent polymer wrapping behaviors were investigated using combinational analyses with a differential scanning calorimeter, transmission electron microscopy, and atomic force microscopy. Furthermore, the conformational behaviors of the PSi's wrapped onto SWNTs were characterized spectroscopically with ordinary UV spectroscopy. Random-coiled and flexible PSi's were successfully wrapped onto small bundles of SWNTs, in which their conformations were changed to fit the surface curvatures of the SWNTs. However, semiflexible PSi could not form a complex with SWNTs, and its conformation remained unchanged even after the same HSVM process. Knowledge gained from this study may lead to a new approach to molecular design of chain-like polymers for efficient wrapping materials for SWNTs.
authors.affiliation: Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan. mnaito@ms.naist.jp
authors.forename: Masanobu
authors.initials: M
authors.lastname: Naito
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Nobusawa
authors.forename: Hisanari
authors.initials: H
authors.lastname: Onouchi
authors.forename: Masashi
authors.initials: M
authors.lastname: Nakamura
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Yasui
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ikeda
authors.forename: Michiya
authors.initials: M
authors.lastname: Fujiki