Viscoelastic Properties of Vapor-grown Carbon Nanofiber/Vinyl Ester Nanocomposites

Nouranian, S., Toghiani, H., Lacy, T., & Pittman, C. (2009). Viscoelastic Properties of Vapor-grown Carbon Nanofiber/Vinyl Ester Nanocomposites. In the proceedings of the International SAMPE Symposium and Exhibition, SAMPE'09, Changing Times – New Opportunities, Are You Prepared? May 18-21. Baltimore, MD.

Abstract

Recently growth has occurred in the use of nanocomposites in automotive and aerospace applications. This is based on emerging data that the use of small amounts of nanoreinforcements compared to large amounts of traditional reinforcements in structural materials, brings about a variety of improvements in mechanical and other properties. Here, a low-cost vapor-grown carbon nanofiber/vinyl ester nanocomposite’s viscoelastic properties have been studied. The study has been conducted using a design of experiments approach, taking into consideration three formulation-related factors: type of carbon nanofiber, use of dispersing agent to enhance the dispersion of nanofibers in the matrix, and carbon nanofiber weight fraction. Nanofiber weight fraction has a major effect on the storage modulus (stiffness), while both the use of dispersing agent and nanofiber weight fraction has major effects on the loss modulus (energy dissipation). An optimized response surface model was thereby developed. Property enhancements over the entire temperature range were further studied and an overall effectiveness of dispersing agent at higher pristine nanofiber loadings was observed. The results of this study can be used as a guide in designing structural nanocomposite based on stiffness and energy-dissipation considerations, which are important in automotive or aerospace strength and crash applications.