12 Aug 2025

Carbon Nanotube-Based Segregated Thermoplastic Nanocomposites Structured via Electromagnetic Melt Processing

Abstract: The EM-processed TPNCs prepared with EM-susceptible carbon nanotubes exhibited a significant enhancement in transport and mechanical properties, outperforming conventionally processed TPNCs. Thus, EM-processed TPNCs demonstrated an ultralow electrical percolation threshold and a remarkable increase in volume electrical conductivity of 8 orders of magnitude at only 1.0 wt % CNT loading. This highlights the superior network formation, level of segregation, and structuring enabled by EM processing. Differential scanning calorimetry and X-ray diffraction revealed EM-processed TPNCs exhibited higher crystallinity and a predominantly α crystal phase compared to hot-pressed TPNCs. Microstructural inspection by electron microscopy disclosed EM processing led to segregated but interconnected multiscale networks of a thin and well-defined CNT interphase that encompassed from the nanoscale of CNTs to the macroscopic scale of TPNCs. The EM-processed TPNCs developed a statistically higher stiffness and in certain cases, even better strength than hot-pressed TPNCs. However, EM-processed TPNCs displayed significantly lower ductility, owing to their higher crystallinity, more brittle crystal α phase, and potential formation of microvoids in the bulk of the TPNCs inherent to the unoptimized EM processing. This work provides an understanding of an alternative and unconventional processing method capable of achieving higher structuring in nanocomposites with advanced multifunctional properties.

24 Sep 2021

Environmental Life Cycle Assessment on CNTRENE® 1030 Material and CNT Based Sensors

Abstract: This report details a study investigating the environmental impacts associated with the development and manufacturing of carbon nanotube (CNT)–based ink (called CNTRENE 1030 material) and novel CNT temperature, flex, and moisture sensors. Undertaken by a private-public partnership involving Brewer Science (Rolla, Missouri), Jordan Valley In-novation Center of Missouri State University (Springfield, Missouri), and the US Army Engineer Research and Development Center (Vicksburg, Mississippi), this work demonstrates the environmental life cycle assessment (ELCA) methodology as a diagnostic tool to pinpoint the particular processes and materials posing the greatest environmental impact associated with the manufacture of the CNTRENE material and CNT-based sensor devices. Additionally, ELCA tracked the degree to which optimizing the device manufacturing process for full production also changed its predicted marginal environmental impacts.

1 Oct 2020

Method Selection Framework for the Quantitation of Nanocarbon Scientific Operating Procedure Series (SOP-C-3): Selection of Methods for Release Testing and Quantitation of Solids, Suspensions, and Air Samples for Carbon-Based Nanomaterials

Abstract: There is significant concern regarding the health and safety risk of nanocarbon (for example, nanotubes, graphene, fullerene), and the cur-rent capability gap for accurately determining exposure levels encumbers risk assessment, regulatory decisions, and commercialization. Given the various analytical challenges associated with the detection and quantitation of nanocarbon, it is unlikely that a single method or technique will prove effective for all forms of nanocarbon, all exposure scenarios, or all possible environmental systems. The optimal approach, or series of techniques, will likely depend on the nature of the material being measured, its concentration, and the matrix in which it is contained. In this work, a preliminary decision framework is presented that assists the user in deter-mining which analytical methods are best suited for a given sample.