Vanillin-Based Epoxy Vitrimers: Looking at the Cystamine Hardener from a Different Perspective

ACS Sustainable Chemistry & Engineering, Journal Year: 2023, Volume and Issue: 11(15), P. 6021 - 6031

Published: April 3, 2023

Epoxy vitrimers encompass many advantages compared to traditional epoxy materials such as recyclability, repairability, and reprocessability. These properties are induced by the incorporation of dynamic reversible covalent bonds. Recently, aromatic disulfide bridges that has expanded development new eco-friendly materials. Herein, we studied a bio-based aliphatic based on cystamine hardener with vanillin-derived bio-sourced prepare fully vitrimers. This article provides comparative study between an benchmark issued from petrol resources. work demonstrated presence this significant influence not only reactivity, but most importantly resulting properties. An interesting yet counterintuitive accelerating effect exchanges was clearly 2 20% molar fraction added formulation. A similar glass transition obtained purely analogue, relaxation times were decreased order magnitude.

Language: Английский

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Disulfide vitrimeric materials based on cystamine and diepoxy eugenol as bio-based monomers

European Polymer Journal, Journal Year: 2023, Volume and Issue: 194, P. 112185 - 112185

Published: May 30, 2023

This study reports the synthesis and characterization of bio-based disulfide vitrimers obtained from diepoxy eugenol cystamine through an epoxy-amine polycondensation process. TREN was added to formulation in varying proportions increase crosslinking density. Although reduced number groups vitrimers, it resulted a maximum relaxation rate at proportion 25%. The were characterized using FTIR, TGA, thermomechanical analysis, their Tg values, determined by DSC, ranged 75 103 °C with increasing proportion. rapidly relax time (τ) 8.5 min 170 °C. addition decreased times 2.8 1.03 catalyzing metathesis achieving balance between bonds content nucleophilic tertiary amines. Creep tests performed wide range temperatures investigate viscosity material below above Tgs. topology freezing calculated creep tests, Tv values all cases confirmed catalytic effect amines on exchange reaction.

Language: Английский

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Harnessing disulfide and transesterification bond exchange reactions for recyclable and reprocessable 3D-printed vitrimers

Reactive and Functional Polymers, Journal Year: 2024, Volume and Issue: 195, P. 105825 - 105825

Published: Jan. 4, 2024

Two new vitrimeric materials have been studied for potential additive manufacturing applications such as 3D-printing. A monomer containing disulfide bonds and β-hydroxyesters was easily synthesized from two low-cost commercially available reagents. Another disulfide-containing comparison purposes. Materials were prepared through a UV-light radical polymerization of methacrylates. The addition reactive diluents poly(ethylene glycol) methyl ether methacrylate (PEGMA) ethylene glycol phenyl (EGPMA) necessary to achieve suitable viscosity the curing well their printability. process controlled by FTIR. Thermomechanical properties investigated means DMTA analysis revealing near-ambient Tg values. Stress relaxation tests revealed that both capable relax 63% initial stress in less than 10 min at 110 °C. recyclability achieved, mechanical thermomechanical recycled samples compared virgin ones great recovery properties. Finally, Digital Light Processing (DLP) technique used print complex structures with high resolution highlighting these 3D printing.

Language: Английский

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Polybenzoxazine-based covalent adaptable networks: A mini-review

Polymer, Journal Year: 2023, Volume and Issue: 287, P. 126426 - 126426

Published: Oct. 25, 2023

Benzoxazines represent a class of thermoset resins known for their exceptional thermal, fire, and mechanical properties. These find wide applications in various industries, including composites electronic components. However, like conventional thermosets, benzoxazines have limitations terms end-of-life options, typically being landfilled or incinerated. To address this concern, researchers been exploring the incorporation dynamic bonds into structure polybenzoxazines to add functionalities such as reprocessability, self-healing, recycling capabilities, develop polybenzoxazine-based covalent adaptable networks (CANs). This mini-review offers an overview recent endeavors focused on introduction within polybenzoxazine structures. It emphasizes synergies between molecular exchanges, transesterification disulfide metathesis, provides comparative summary properties achieved by materials developed context. By leveraging strengths benzoxazine structures, aims foster exploration development innovative approaches that combine unique CANs, enabling more sustainable environmentally friendly materials.

Language: Английский

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Eugenol-based dual-cured materials with multiple dynamic exchangeable bonds

European Polymer Journal, Journal Year: 2024, Volume and Issue: 206, P. 112782 - 112782

Published: Jan. 19, 2024

In the present work, preparation of sustainable thermosets has been approached simultaneously from three different points view: a) use bio-based monomers chemically modified through green methodologies, b) adoption dual curing click-type reactions to implement more efficient manufacturing processes, and c) inclusion interchangeable groups in network, enable reuse recycling material at end its useful life avoid waste generation. The first goal by synthesizing a greener way an acrylate-epoxy derivative eugenol (AEEU) glycerol triacrylate (GTA), both biobased resources. Then, second approach was addressed using cystamine as crosslinker obtain materials dual-curing procedure based on "click" aza-Michael reaction epoxy-amine reaction. Intermediate final could be prepared with tailorable properties controlling molar ratio AEEU GTA. By DSC rheology, we evaluate sequentiality gelation process. Finally, covalent adaptable networks (CANs) contained types dynamic bonds (disulfide, esters, β-aminoesters) their thermomechanical were tested DMA revealing Tgs above room temperature 47 70 °C. Bending tests break performed mechanical reaching values up 90 MPa stress 7 % deformation. Stress relaxation showed that all relax relatively low temperatures (120 °C) less than 21 min. associative dissociative behavior these investigated rheology clear drop modulus high frequencies when used crosslinker. Moreover, reprocessability obtaining homogeneous samples no significant changes chemical thermal highlighting great potential wide range possibilities many fields CANs.

Language: Английский

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Trapping bond exchange phenomenon revealed for off-stoichiometry cross-linking of phase-separated vitrimer-like materials

Soft Matter, Journal Year: 2024, Volume and Issue: 20(13), P. 2961 - 2968

Published: Jan. 1, 2024

Unusual relaxation and creep properties by the trapping bond exchange phenomenon is revealed for vitrimer-like materials with exchangeable domains of quaternized pyridines, in special case off- stoichiometric cross-linking condition.

Language: Английский

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Dual reconfigurable network from a semi-crystalline functional polyolefin

Polymer, Journal Year: 2024, Volume and Issue: 297, P. 126864 - 126864

Published: March 1, 2024

Language: Английский

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Reprocessable and Repairable Carbon Fiber Reinforced Vitrimer Composites Based on Thermoreversible Dynamic Covalent Bonding

Composites Science and Technology, Journal Year: 2024, Volume and Issue: 255, P. 110731 - 110731

Published: June 28, 2024

Language: Английский

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Towards fast relaxation rates and creep resistance in disulfide vitrimer-like materials

Reactive and Functional Polymers, Journal Year: 2023, Volume and Issue: 193, P. 105764 - 105764

Published: Oct. 29, 2023

Reaching a delicate balance between polymer flow for reprocessing and mechanical robustness at service temperatures remains challenge in designing dynamic networks. The demand creep-resistant materials with fast relaxation rates relatively low is crucial research topic the academic world. In this study, we present preparation of series disulfide vitrimeric by curing two commercially available aromatic aliphatic epoxy resins cystamine. Through careful variation proportions resins, properties final can be properly tailored. completion was confirmed using FTIR spectrometry, thermal stability all evaluated TGA. thermomechanical were investigated DMA analysis, obtaining glass transition (Tgs) above 60 °C high rigidity glassy state depending on proportion resin. Extensive stress tests unveiled remarkable behavior, capable relaxing 63% initial less than 2 min 140 °C. in-depth creep experiments not only allowed determining material viscosity topology freezing (Tvs) but also offered control over room temperature, formulation composition. Dilatometry tensile provided further insights into materials' characteristics. self-healing self-welding behavior enabled metathesis exchange reactions evaluated, revealing total recovery process short times comparable modulus welded samples. facile preparation, commercial availability monomers, excellent thermosetting highlight immense potential materials.

Language: Английский

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Sequence-Defined Tertiary Amine-Based Oligomer Employing a Scalable, Support-Free, and Protection/Deprotection-Free Iterative Strategy

ACS Macro Letters, Journal Year: 2024, Volume and Issue: 13(1), P. 65 - 72

Published: Jan. 2, 2024

Sequence-defined oligomers (SDOs) with their unique monomeric sequence and customizable nature are attracting the attention of researchers globally. The structural functional diversity attainable in SDOs makes this platform promising, albeit challenges synthesis. Herein, we report design synthesis a novel class SDO by incorporating tertiary amines into backbone from commercially available inexpensive materials. Tertiary were selected due to various material biomedical applications. Even though purification amine compounds challenging, significant applications, such as pharmaceuticals, catalysts, surfactants, corrosion inhibitors, dye intermediates, polymer additives, rubber accelerators, gas treating agents, agriculture, analytical chemistry, make them fascinating. synthetic strategy that is designed here extremely efficient economical for scalable support-free, protection–deprotection chemistry-free, catalyst/template-free. Most importantly, no extra monomer required here. key reactions employed (i) transformation hydroxy group halide (ii) substitution secondary units. Including purifying processes, multigram 4-mer was completed 12–14 h. established synthesizing two different sequences SDOs. characterized 1H NMR LC-MS. tandem MS (MS/MS) experiment conducted order validate over chain. Furthermore, advanced ways: increasing chain length via attaching linker, which provides rapid method chain, postsynthetic modification other groups, including guanidine biological importance well-known fluorophore dansyl significance.

Language: Английский

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