Comparative Study of Nanocomposites with 0.01% to 1.0% Mass Loading of Multiwall Carbon Nanotube-Polymer Nanocomposites by Raman, SEM and XPS Measurement Techniques
Yanmei Piao, Vipin Tondare, Chelsea S. Davis, Justin Gorham, Jeffrey W. Gilman, Keana Scott, Andras Vladar, Angela Hight Walker
Substantial ongoing research efforts are investigating the production of novel composite material enhanced by the incorporation of nanomaterial fillers such as multiwall carbon nanotubes (MWCNTs). While the addition of MWCNTs have been shown to improve the properties of polymer nanocomposites, it is critical to develop robust methods to detect and quantify MWCNTs in nanocomposites to assess potential hazards and risks from the use of MWCNTs in composite materials. Therefore, we have assessed the effectiveness of three commonly applied characterization methods on a series of MWCNT epoxy nanocomposites (MWCNT concentrations spanned two orders of magnitude from 0.01 % to 1.0 % by nominal mass fraction). The methods used for this study were X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and scanning electron microscopy (SEM). A general trend of positive correlation between signal intensity and MWCNT mass loading was observed by both Raman spectroscopy and XPS, although the relatively large error bars were indicative of an inhomogeneous distribution of MWCNT in the composites. Raman spectroscopy was capable of consistently detecting MWCNTs at the lowest nominal concentration tested (0.01 %) while for XPS, MWCNTs were consistently detected at ≈ 0.5 %. To also assess the comparability of measurements of the spatial distribution of MWCNTs within the nanocomposite samples, analysis of the same locations of two composite samples with nominal MWCNT mass fractions of 0.3 % and 1.0 % using Raman microscopy and SEM revealed an identical spatial resolution and detectability of MWCNT clusters and with the higher mass loading sample having a higher number of MWCNT rich domains. This analysis also revealed a potential artifact if SEM analysis of the MWCNT spatial distribution was conducted before Raman spectroscopy analysis, suggesting a sequential characterization order should be followed when multiple techniques are involved.
, Tondare, V.
, Davis, C.
, Gorham, J.
, Gilman, J.
, Scott, K.
, Vladar, A.
and Hight, A.
Comparative Study of Nanocomposites with 0.01% to 1.0% Mass Loading of Multiwall Carbon Nanotube-Polymer Nanocomposites by Raman, SEM and XPS Measurement Techniques, Composites Science and Technology, [online], https://doi.org/10.1016/j.compscitech.2021.108753, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=921785
(Accessed May 10, 2021)