Catalyst-Free and Sustainable Bio-Based Epoxy Vitrimer Prepared Based on Ester Exchange and Imine Bonding

Journal of Polymers and the Environment, Journal Year: 2024, Volume and Issue: 32(10), P. 4912 - 4924

Published: May 6, 2024

Language: Английский

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Fully biobased, catalyst-free vitrimers from tannic acid: facile combination of mechanical robustness, recyclability and sustainability

Green Chemistry, Journal Year: 2024, Volume and Issue: 26(12), P. 7113 - 7122

Published: Jan. 1, 2024

The unique hyperbranched structure formed from tannic acid provides both robust mechanical properties and catalyst-free recyclability to fully biobased transesterification vitrimers.

Language: Английский

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Tuning the Dynamics of Enamine-One-Based Vitrimers through Substituent Modulation of Secondary Amine Substrates

Macromolecules, Journal Year: 2022, Volume and Issue: 55(22), P. 10124 - 10133

Published: Nov. 3, 2022

Polymer networks embedded with dynamic covalent bonds have been demonstrated to be capable of network reconfiguration. This reprocessability is often related the dynamics or flowability, precise control which highly depends on underlying chemistry. Particularly, vitrimer materials flow at a constant crosslinking density because associative chemistry involved. Here, we report fabrication enamine-one vitrimers through an amino-yne click reaction using secondary amine substrates. Compared primary amines, amine-based mild and yields less gel content (70 vs 97%) in our curing system. By modulating substituents amine, show that activation energy exchange increases (52–90 kJ/mol) increasing steric hindrance (piperidyl ∼ methyl < ethyl isopropyl tert-butyl), similar trend was observed networks. Interestingly, piperidine exhibits reactivities (including yielded dynamics) comparable amines constrained cyclic structure. study not only enriches scope substrates for but also offers convenient means tune substrate choices combination strategies (i.e., mixing various amines).

Language: Английский

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Harnessing β-Hydroxyl Groups in Poly(β-Amino Esters) toward Robust and Fast Reprocessing Covalent Adaptable Networks

Macromolecules, Journal Year: 2022, Volume and Issue: 55(23), P. 10366 - 10376

Published: Nov. 28, 2022

Poly(β-amino esters) (PBAEs), which include tertiary amines at the β-position of ester linkages, are promising in biomaterials due to their biodegradability and pH responsiveness. Such characteristics molecular structure also appealing for designing catalyst-free covalent adaptable networks (CANs), but this has rarely been explored literature. Herein, we synthesize a series PBAE-based CANs by aza-Michael addition, using diacrylate monomers with without β-hydroxyl groups, triamine crosslinker. By leveraging hydrogen bonding, thermal mechanical properties these effectively tuned through monomer composition. Owing numerous serving as internal catalysts, undergo network exchange dynamic reaction. Interestingly, increasing amount groups accelerates overall stress relaxation from synergistic effects transesterification (associative type) lower temperatures reaction (dissociative higher temperatures. Based on features, successfully demonstrate reprocessing healing elevated under mild pressure, well shape memory reconfiguration. Thus, controlling group concentration is useful strategy enhancing both strength rate.

Language: Английский

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Biobased catalyst-free covalent adaptable networks based on CF₃-activated synergistic aza-Michael exchange and transesterification

Journal of Materials Chemistry A, Journal Year: 2022, Volume and Issue: 10(47), P. 25085 - 25097

Published: Jan. 1, 2022

This study reports the synthesis and characterization of biobased CANs incorporating CF 3 -activated aza-Michael bonds ester groups showing remarkable reprocessing abilities high activation energy.

Language: Английский

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