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DOE OSTI · 3740880

3D Printing Epoxy Thermosets: Additive Manufacturing of Polymerization-Induced Phase Separating Materials

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Van Meter, Kylie Elizabeth [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000214588664), Jones, Brad Howard [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000336749075). 2025-10-01. 3D Printing Epoxy Thermosets: Additive Manufacturing of Polymerization-Induced Phase Separating Materials. https://doi.org/10.2172/3740880

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Method of tuning physical properties of thermosets

Polymerization-induced phase separation enables fine control over thermoset network morphologies, yielding heterogeneous structures with domain sizes tunable over 1-100 nm. However, the controlled chain-growth polymerization techniques exclusively employed to regulate morphology at these length scales are unsuitable for most thermoset materials typically formed through step-growth mechanisms. By employing binary mixtures in place of the classic constituents of phase-separating thermosets—resin, curing agent, and secondary polymer—facile tunability over morphology can be achieved through a single compositional parameter. Indeed, this method yields morphologies spanning nano-scale to macro-scale, controlled by the relative reactivities and thermodynamic compatibility of the network components. Due to the connection between chain dynamics and microstructure in these materials, the tunable morphology enables exquisite control over glass transition and other physical and mechanical properties.

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