Henry David J, Evans Evan, Yarovsky Irene
School of Applied Sciences, RMIT University, GPO Box 2476V, Victoria, 3001, Australia.
J Phys Chem B. 2006 Aug 17;110(32):15963-72. doi: 10.1021/jp0622886.
This study examines the interaction of neutral and charged fullerenes with model silica and polyester surfaces. Molecular dynamics simulations at 298 K indicate that van der Waals forces are sufficiently strong in most cases to cause physisorption of the neutral fullerene particle onto the surfaces. The fullerenes are unable to penetrate the rigid silica surface but are generally able to at least partially infiltrate the flexible polymer surface by opening surface cavities. The introduction of charge to the fullerene generally leads to an increase in both the separation distance and Work of Separation with silica. However, the charged fullerenes generally exhibit significantly closer and stronger interactions with polyester films, with a distinct tendency to absorb into the "bulk" of the polymer. The separation distance and Work of Separation of C60 with each of the surfaces also depend greatly on the sign, magnitude, and localization of the charge on the particle. Cross-linking of the polyester can improve resistance to the neutral fullerene. Functionalization of the polyester surface (F and OH substituents) has been shown to prevent the C60 from approaching as close to the polyester surface. Fluorination leads to improved resistance to positively charged fullerenes, compared to the unmodified polyester. However, hydroxylation generally enables greater adhesion of charged fullerenes to the surface due to H-bonding and electrostatic attraction.
本研究考察了中性和带电富勒烯与模型二氧化硅和聚酯表面的相互作用。在298K下进行的分子动力学模拟表明，在大多数情况下，范德华力足够强，足以使中性富勒烯颗粒物理吸附到表面上。富勒烯无法穿透刚性二氧化硅表面，但通常能够通过打开表面空洞至少部分渗透到柔性聚合物表面。向富勒烯引入电荷通常会导致与二氧化硅的分离距离和分离功均增加。然而，带电富勒烯通常与聚酯薄膜表现出明显更紧密和更强的相互作用，并且有明显的吸收到聚合物“本体”中的趋势。C60与每个表面的分离距离和分离功也极大地取决于颗粒上电荷的符号、大小和定位。聚酯的交联可以提高对中性富勒烯的抗性。聚酯表面的功能化（F和OH取代基）已被证明可以防止C60接近聚酯表面。与未改性的聚酯相比，氟化导致对带正电富勒烯的抗性提高。然而，由于氢键和静电吸引，羟基化通常使带电富勒烯与表面的粘附力更强。
