Interaction of Polymers with Single-Wall Carbon Nanotubes

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• 作者：Frank K. Brunecker ; Friedrich Schöppler ; Tobias Hertel
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：May 12, 2016
• 年：2016
• 卷：120
• 期：18
• 页码：10094-10103
• 全文大小：541K
• 年卷期：0
• ISSN：1932-7455

文摘

Polymers are widely used for postsynthesis processing, purification, and individualization of single-wall carbon nanotubes (SWNTs) in aqueous or organic solvent environments. Here, the interaction of single-stranded DNA oligomers (ssDNA) and of a polyfluorene copolymer (F8T2) with (6,5) SWNTs was investigated from desorption kinetics and in the case of ssDNA also using adsorption isotherms. Eyring analysis of desorption rate constants reveals a linear increase of activation enthalpies with ssDNA oligomer length until Δ_desHp>‡p> saturates at (155 ± 5) kJ·molp>–1p> for oligomers exceeding the ssDNA Kuhn length of about 6 nm. The Gibbs energy for desorption of Δ_desGp>‡p> = (96 ± 1) kJ·molp>–1p> is length-independent because of entropy–enthalpy compensation. The saturation of desorption energies at the high polymer coverages studied here is attributed to incomplete adsorption with typically no more than a single Kuhn segment of a polymer attached to a SWNT.