TY - JOUR

T1 - Thermally Latent Bases in Dynamic Covalent Polymer Networks and their Emerging Applications

AU - Reisinger, David

AU - Kriehuber, Matthias Udo

AU - Bender, Marcel

AU - Bautista-Anguís, Daniel

AU - Rieger, Bernhard

AU - Schlögl, Sandra

N1 - Publisher Copyright: © 2023 Wiley-VCH GmbH.

PY - 2023/3/14

Y1 - 2023/3/14

N2 - A novel strategy allowing a temporal control of dynamic bond exchange in covalently cross-linked polymer networks via latent transesterification catalysts is introduced. Obtained by a straight-forward air- and water-tolerant synthesis, the latent catalyst is designed for an irreversible temperature-mediated release of a strong organic base. Its long-term inactivity at temperatures below 50°C provides the unique opportunity to equip dynamic covalent networks with creep resistance and high bond exchange rates, once activated. The presented thermally latent base catalyst is conveniently introducible in readily available building blocks and, as proof of concept, applied in a radically polymerized thiol-ene network. Light-mediated curing is used for 3D printing functional objects on which the possibility of spatially controlled reshaping and welding based on dynamic transesterification are illustrated. Since the catalyst is thermally activated, limitations regarding sample geometry and optical transparency do not apply, which facilitates a transfer to well-established industrial technologies. Consequently, fiber-reinforced and highly filled magneto-active thiol-ene polymer composites are fabricated by a thermal curing approach. The on-demand activation of dynamic transesterification is demonstrated by (magneto-assisted) reshaping experiments, highlighting a wide range of potential future applications offered by the presented concept.

AB - A novel strategy allowing a temporal control of dynamic bond exchange in covalently cross-linked polymer networks via latent transesterification catalysts is introduced. Obtained by a straight-forward air- and water-tolerant synthesis, the latent catalyst is designed for an irreversible temperature-mediated release of a strong organic base. Its long-term inactivity at temperatures below 50°C provides the unique opportunity to equip dynamic covalent networks with creep resistance and high bond exchange rates, once activated. The presented thermally latent base catalyst is conveniently introducible in readily available building blocks and, as proof of concept, applied in a radically polymerized thiol-ene network. Light-mediated curing is used for 3D printing functional objects on which the possibility of spatially controlled reshaping and welding based on dynamic transesterification are illustrated. Since the catalyst is thermally activated, limitations regarding sample geometry and optical transparency do not apply, which facilitates a transfer to well-established industrial technologies. Consequently, fiber-reinforced and highly filled magneto-active thiol-ene polymer composites are fabricated by a thermal curing approach. The on-demand activation of dynamic transesterification is demonstrated by (magneto-assisted) reshaping experiments, highlighting a wide range of potential future applications offered by the presented concept.

KW - Dynamic Covalent Polymer Networks

KW - Vitrimers

KW - Low Creep

KW - On-demand Activation

KW - Thermolatent Catalysts

KW - 3D Printing

KW - Composites

UR - http://www.scopus.com/inward/record.url?scp=85156275147&partnerID=8YFLogxK

U2 - 10.1002/adma.202300830

DO - 10.1002/adma.202300830

M3 - Article

C2 - 36916976

AN - SCOPUS:85156275147

VL - 35.2023

JO - Advanced materials

JF - Advanced materials

SN - 0935-9648

IS - 24

M1 - 2300830

ER -