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Multimaterial Thermoset Synthesis: Switching Polymerization Mechanism with Light Dosage
Yuting Ma1, Reagan J Dreiling1, Elizabeth A Recker2
1Department of Chemistry, Cornell University, Ithaca, New York 14853, United States.
ACS Central Science
|December 5, 2024
Summary
A novel photopolymerization method allows spatial control over material properties by switching between radical and cationic polymerization using light dosage. This technique enables the creation of complex multimaterial thermosets from standard resins.
Area of Science:
- Polymer Chemistry
- Materials Science
- Photochemistry
Background:
- Synthesizing thermoset materials with controlled physical properties is challenging.
- Existing methods often lack spatial control or require specialized resins.
Purpose of the Study:
- To develop a photoinitiated polymerization method for spatial control of radical and cationic polymerization.
- To enable the creation of multimaterial thermosets using readily available resins.
Main Methods:
- Developed Switching Polymerizations by Light Titration (SPLiT) using substoichiometric photobuffers and photoacid generators.
- Controlled polymerization by varying monochromatic light dosage (intensity or irradiation time).
- Utilized commercially available resins with inexpensive photobuffers like tetrabutylammonium chloride.
Main Results:
- Achieved spatial switching between radical and cationic polymerization based on light dosage.
- Demonstrated patterning capabilities for constructing multimaterial thermosets.
- Enabled the preparation of multimodulus constructs via grayscale vat photopolymerization 3D printing.
Conclusions:
- The SPLiT method offers a versatile approach for creating complex thermoset architectures.
- This technique simplifies the production of advanced materials by using standard resins.
- It opens possibilities for sophisticated 3D printing applications requiring spatially defined properties.
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