Solvent-Free Ultrasonic Dispersion of Nanofillers in Epoxy Matrix

• Main Authors: Benjamin Zanghellini, Patrick Knaack, Sebastian Schörpf, Karl-Heinz Semlitsch, Helga C. Lichtenegger, Bernhard Praher, Maria Omastova, Harald Rennhofer
• Format: Article
• Language: English
• Published: MDPI AG 2021-01-01
• Series: Polymers
• Subjects: ultrasonication; dispersion; functionalization; carbon nanotubes; rheology
• Online Access: https://www.mdpi.com/2073-4360/13/2/308

Dispersion of carbon nanotubes and carbon nanofibers is a crucial processing step in the production of polymer-based nanocomposites and poses a great challenge due to the tendency of nanofillers to agglomerate. One of the most effective methods for dispersion is the use of a three-roll mill, which is a well-established method and results in agglomerates below 5 µm. Nevertheless, this process is time-consuming and thus a limiting factor for industrial applications. Our aim was to establish an easy and efficient ultrasonic dispersion process, characterize the dispersion parameters, and compare both methods, ultrasonication and the three-roll mill. We applied rheological tests and analyzed the agglomerate sizes by an image fit of the microscopy images. All these analyses combined deliver a valuable set of information about the dispersion’s quality and, therefore, allows the improvement and further adaptation of the dispersion process.