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DOE OSTI · 1843211

3D Printable All-Polymer Epoxy Composites

Shen, Liyang·Wang, Tung-ping·Lee, Ting-Han·Forrester, Michael·Becker, Andrew·Torres, Sabrina·Pearson, Connor·Cochran, Eric W.
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Abstract

Herein, 3D printable polymer-toughened epoxy resin composites are reported. Epoxy resins are widely used due to their excellent properties, such as thermal and chemical stability. However, their applications are limited by traditional mold-based manufacturing and their high brittleness. Mixtures of homopolymers, diblock copolymers, and triblock copolymers composed of poly(phenylene ether), poly(styrene), poly(methyl methacrylate), and poly(ethylene oxide) that self-assemble into micelles in the uncured resin are employed, providing a balance of structure, creep resistance, and flowability that enables 3D printing processing techniques and a retention of dimensional fidelity from the time of printing throughout the cured state. The precured ink is solid at room temperature and has strong shear-thinning behavior at elevated temperature for printing. As the printed parts cure, the polymer morphology evolves via reaction induced phase separation to yield finished composites with enhanced mechanical properties, including a 40% increase in the impact strength compared to the neat epoxy, without compromising thermal properties.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY3D printingblock copolymercompositesepoxytoughening

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Shen, Liyang, Wang, Tung-ping, Lee, Ting-Han, Forrester, Michael, Becker, Andrew, Torres, Sabrina, Pearson, Connor, Cochran, Eric W.. 2021-10-01. 3D Printable All-Polymer Epoxy Composites. https://doi.org/10.1021/acsapm.1c00889

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