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Solvent-Free Ultrasonic Dispersion of Nanofillers in Epoxy Matrix.

ABSTRACT: 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.

SUBMITTER: Zanghellini B

PROVIDER: S-EPMC7835899 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Solvent-Free Ultrasonic Dispersion of Nanofillers in Epoxy Matrix.

Zanghellini Benjamin B Knaack Patrick P Schörpf Sebastian S Semlitsch Karl-Heinz KH Lichtenegger Helga C HC Praher Bernhard B Omastova Maria M Rennhofer Harald H

Polymers 20210119 2

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 eas ...[more]

PMID: 33478153

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