Gaikwad Prashik S, Kowalik Malgorzata, van Duin Adri, Odegard Gregory M
Michigan Technological University Houghton MI 49931 USA
Pennsylvania State University, State College PA 16801 USA.
RSC Adv. 2022 Oct 11;12(45):28945-28953. doi: 10.1039/d2ra05550c.
Flattened carbon nanotubes (flCNTs) are a primary component of many carbon nanotube (CNT) yarn and sheet materials, which are promising reinforcements for the next generation of ultra-strong composites for aerospace applications. Significant improvements in the performance of CNT materials can be realized with improvements in the load transfer between flCNTs, which are generally oriented at different angles with respect to each other. An intriguing approach to improving the load transfer is irradiation-induced chemical crosslinking between adjacent flCNTs. The objective of this research is to use molecular dynamics (MD) simulations to predict the behavior of flCNT junctions with 0- and 90-degree orientations and varying levels of crosslinking. The results indicate that crosslinking improves the flCNT interfacial load transfer for both orientations, but degrades the flCNT tensile response. The primary toughening mechanism at the flCNT/flCNT interface is the formation of carbon chains that provide load transfer up to the point of total rupture. Based on these results, it is clear that irradiation-induced crosslinking is beneficial in CNT-based composite systems in which interfacial load transfer between flCNTs is of primary importance, even though individual flCNTs may lose some mechanical integrity with crosslinking.
扁平碳纳米管（flCNTs）是许多碳纳米管（CNT）纱线和片状材料的主要成分，这些材料有望成为下一代用于航空航天应用的超强复合材料的增强材料。随着flCNTs之间载荷传递的改善，碳纳米管材料的性能可得到显著提升，而flCNTs通常相互呈不同角度取向。一种引人关注的改善载荷传递的方法是相邻flCNTs之间的辐照诱导化学交联。本研究的目的是使用分子动力学（MD）模拟来预测0度和90度取向以及不同交联水平的flCNT结的行为。结果表明，交联对两种取向的flCNT界面载荷传递均有改善作用，但会降低flCNT的拉伸响应。flCNT/flCNT界面处的主要增韧机制是碳链的形成，这些碳链在完全断裂之前提供载荷传递。基于这些结果，很明显，辐照诱导交联在基于碳纳米管的复合系统中是有益的，在该系统中flCNTs之间的界面载荷传递至关重要，尽管单个flCNTs可能会因交联而失去一些机械完整性。
