Abstract

The reinforcement effect of boron nitride nanotube (BNNT) and carbon nanotube (CNT) on thermoelastic behavior of poly(methyl methacrylate) (PMMA) nanocomposites was compared through a molecular dynamics (MD) simulation and mean-field micromechanics model. Uniaxial tension, shearing, cooling down, and pullout simulations were implemented in MD simulations. In micromechanics, the multi-inclusion (M–I) model was adopted. Both nanocomposites showed similar transversely isotropic elastic constants and coefficients of thermal expansion (CTEs). BNNTs provided better interfacial load transfer and dispersibility with PMMA; meanwhile, CNTs reduced the CTE of the matrix more. For both nanocomposites, the thermoelastic behavior was sensitive to the interfacial imperfection and interphase zone.

摘要

通过分子动力学 (MD) 模拟和平均场微力学模型比较了氮化硼纳米管 (BNNT) 和碳纳米管 (CNT) 对聚甲基丙烯酸甲酯 (PMMA) 纳米复合材料的热弹性行为的增强作用。在 MD 模拟中实施了单轴拉伸、剪切、冷却和拉拔模拟。在微力学中，采用了多夹杂物 (M-I) 模型。两种纳米复合材料都显示出相似的横向各向同性弹性常数和热膨胀系数 (CTE)。BNNT 与 PMMA 一起提供了更好的界面负载转移和分散性；同时，碳纳米管进一步降低了基体的热膨胀系数。对于这两种纳米复合材料，热弹性行为对界面缺陷和界面区都很敏感。