Experimental-computational study of shear interactions within double-walled carbon nanotube bundles.

摘要: The mechanical behavior of carbon nanotube (CNT)-based fibers and nanocomposites depends intimately on the shear interactions between adjacent tubes. We have applied an experimental-computational approach to investigate CNTs within individual double-walled (DWNT) bundles. force required pull out inner bundle DWNTs from outer shell was measured using in situ scanning electron microscopy methods. normalized per CNT-CNT interaction (1.7 ± 1.0 nN) found be considerably higher than molecular mechanics (MM)-based predictions for bare (0.3 nN). This MM result is similar that results exposure newly formed CNT surfaces, indicating observed pullout arises factors beyond what arise potential energy effects associated with CNTs. Through further theoretical considerations we show experimentally may include small contributions carbonyl functional groups terminating free ends CNTs, corrugation interactions, polygonization nanotubes due their mutual interactions. In addition, surface groups, such as hydroxyl exist are play unimportant role. All these account less half ~1.7 nN force. However, partially pulled-out bundles not back into after broken, suggesting dissipation responsible more sum agree experimental error.