The Mechanics of Inorganic Nanotubes from Molecules to Materials

摘要：无机纳米管从分子到材料的力学spaul R. Heyliger和Anthony Rappe的土木工程和化学系科罗拉多州立大学fort Collins CO 80523无机单壁纳米管（SWNT）在三个尺寸尺度范围内建模，这些尺度代表了将纳米管视为单个元素或复合系统内的组件时的关键物理特性。纳米管将首先使用分子力学力场方法的扩展在原子尺度上建模。我们将对这些元件通常承受的各种载荷进行模拟。与这些变形相关的能量可以作为变形的函数来计算。其次，我们将这些能量等同于等效膜-壳连续体模型的能量。这种局部特性可用于确定具有代表性的连续介质壳或纤维的壁厚和弹性常数。第三种也是最后一种模型利用壳表示的几何和材料特性信息，将纳米管视为长而有弹性的材料或复合材料中的有限纤维。碳纳米管和无机纳米管都将被研究，后者将包括甲基铝烷、甲基氮化铝、小直径和大直径硫化钼、氮化硼和混合碳硼氮化。

ABSTRACTThe Mechanics of Inorganic Nanotubes from Molecules to MaterialsPaul R. Heyliger and Anthony Rappe'Departments of Civil Engineering and ChemistryColorado State UniversityFort Collins CO 80523 Inorganic single wall nanotubes (SWNT) are modeled over a range of three size scales that represent the key physical characteristics when considering nanotubes as individual elements or as components within a composite system. The nanotubes will first be modeled at the atomic scale using an extension of the molecular mechanics force field approach. Simulations will be completed for SWNT under the various types of loadings under which these elements will usually be subjected. The energies associated with these distortions can then be computed as a function of deformation. Second, we equate these energies with those of an equivalent membrane-shell continuum model. This localized behavior can then be used to determine the wall thickness and elastic constants for the representative continuum shell or fiber. The third and final model uses the information on the geometric and material properties of the shell representation to treat the nanotube as long, flexible elastica or as a finite fiber within a composite. Both carbon and inorganic nanotubes will be studied, the latter class of which will include methylalumoxane, methylalumium methylnitride, small and large diameter molybdenum sulfide, boron nitride, and mixed carbon boronnitride.