European Polymer Journal, Journal Year: 2023, Volume and Issue: 198, P. 112420 - 112420
Published: Sept. 9, 2023
Language: Английский
Macromolecules, Journal Year: 2022, Volume and Issue: 55(8), P. 3106 - 3115
Published: April 6, 2022
Although bio-based benzoxazines (BZs) have been explored widely as sustainable thermosetting resins, few high-performance BZs prepared completely from natural renewable resources. In this study we synthesized a fully multifunctional bisbenzoxazine (AP-fa-BZ) in high yield and purity apigenin (AP), furfurylamine (fa), benzaldehyde by using both solvent solventless approaches. Fourier transform infrared (FTIR) spectroscopy, high-resolution mass spectrometry, one- two-dimensional nuclear magnetic resonance spectroscopy confirmed the chemical structure of AP-fa-BZ. We then used dynamic mechanical analysis, differential scanning calorimetry (DSC), thermogravimetric situ FTIR to examine thermal characteristics AP-fa-BZ before after its ring-opening polymerization (ROP). DSC revealed that temperature required for formation poly(AP-fa-BZ) through ROP (236.3 °C) was significantly lower than typical 4-phenyl-3,4-dihydro-2H-1,3-benzoxazine (Pa-type) monomer due positive catalytic effect phenolic OH groups AP structure. After at 250 °C, resulting possessed decomposition (Td10 = 395 °C), char (52 wt %), glass transition (Tg 283 °C). Contact angle measurements tunable surface properties Finally, resin functioned an antibacterial agent against Staphylococcus aureus Escherichia coli.
Language: Английский
Citations
79
Chemical Communications, Journal Year: 2025, Volume and Issue: unknown
Published: Jan. 1, 2025
Bio-based vitrimers represent a green and sustainable bridge between thermoplastics thermosets.
Language: Английский
Citations
2
Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 453, P. 139895 - 139895
Published: Oct. 20, 2022
The meaningful concept of circular economy has prompted the scientific community to re-think design materials. In this work, lignin-based benzoxazines (LBZs) thermosets with tuneable properties were synthesized in agreement principles Green Chemistry, following a straightforward two-step synthetic route. reactivity soda lignin was enhanced by its esterification phloretic acid, naturally occurring phenolic acid. Thereafter, resulting structure enriched rings no ortho substituents, used prepare LBZs precursors bio-based primary amine via Mannich-like ring-closure reaction. and each LBZ precursor confirmed multiple NMR techniques, Fourier transform infrared spectroscopy, elemental analysis, gel permeation chromatography, differential scanning calorimetry, rheology, solubility assays. Lignin-based polybenzoxazine high mass fraction (between 46 66 wt.%) obtained curing vacuum compression molding manufacture process. exhibit single-phase X-ray computed tomography Tg ranging from 136 197 °C, storage moduli 0.5 3.1 GPa. features tuned depending on close oxazine ring. Stearylamine confers good processability yields hydrophobic coatings water contact angle reaching 91°. Furfurylamine-based generate high-Tg (197 °C) fire-resistant materials peak heat release rate no>47 W.g−1. Finally, ethanolamine produces capable internally catalysed bond exchange transesterification, providing vitrimeric such as fast stress relaxation (τ*200 °C = 233 s) complete circularity.
Language: Английский
Citations
65
ACS Sustainable Chemistry & Engineering, Journal Year: 2024, Volume and Issue: 12(20), P. 7739 - 7747
Published: May 9, 2024
A biobased reprocessable and degradable polybenzoxazine vitrimer was prepared by introducing dynamic imine bonds. An aldehyde-containing benzoxazine monomer (VSA) synthesized through the Mannich reaction of vanillin, stearylamine, paraformaldehyde, then VSA reacted with 1,12-dodecanediamine to prepare an imine-containing (VSA-dda). The curing behaviors VSA-dda were characterized in situ Fourier-transform infrared spectroscopy differential scanning calorimetry. exchange bonds within cross-linked network (PVSA-dda) studied stress relaxation experiments. Due presence bonds, PVSA-dda could be reprocessed hot-pressing at 140 °C under 2 MPa. exhibited a shape memory property recover its original heating 100 °C. degradation performance investigated various conditions, results showed that degraded 29 min acidic solution tetrahydrofuran water 50
Language: Английский
Citations
15
Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 484, P. 149585 - 149585
Published: Feb. 12, 2024
Language: Английский
Citations
13
Macromolecules, Journal Year: 2024, Volume and Issue: 57(5), P. 2078 - 2089
Published: Feb. 24, 2024
This study introduces a straightforward and efficient route for synthesizing self-healable polybenzoxazine networks by utilizing dynamic imine bond exchanges under mild conditions. The process involves combining polyethylenimines with aldehyde-functional bisbenzoxazine, which was produced from vanillin, using Sc(OTf)3 catalyst subjecting them to moderate heating at 150 °C. Remarkably, the resulting films exhibit good self-healing capabilities low temperatures pressures, without requiring any additional additives facilitate healing process. degree of recovery assessed through tensile tests, while rheologic measurements were utilized analyze stress relaxation activation energy bonding, providing insights into Additionally, comprehensive spectral characterizations investigations thermal behaviors conducted gain deeper understanding material's properties performance. Moreover, demonstrated enhanced hydrolysis stability compared conventional imine-based systems, benefiting specific Mannich linkages inherent hydrophobic nature polybenzoxazines.
Language: Английский
Citations
11
ACS Sustainable Chemistry & Engineering, Journal Year: 2024, Volume and Issue: 12(3), P. 1247 - 1254
Published: Jan. 10, 2024
Developing biomass resins with high thermal resistance and mechanical performance through a green strategy is an interesting challenge. Increasing the functionality of oxazine ring favorable to improve strength resins; however, no tri- or more functional benzoxazine monomers synthesized using have been reported. Herein, two novel trifunctional (coded as DPTA-f DPTR-f) very low melting points (61, 49 °C) were raw materials (diphenolic acid, tyramine, tyrosol, furfurylamine) solvents (ethanol water). The cured DPTR-f, designed P(DPTA-f) P(DPTR-f), not only exhibit storage moduli (3600 3080 MPa) tensile (65.0 55.1 but also glass transition temperature (Tg = 328, 302 initial degradation (351 350 °C), especially exhibits bigger Tg than all prepared (SCI database). They good flame retardancy. above excellent processing nature DPTR-f together competitive benefits from unique chemical aggregate state structures biobased benzoxazines.
Language: Английский
Citations
10
Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(19), P. 13367 - 13376
Published: May 2, 2024
The use of internal catalysts has emerged as a pivotal design principle to facilitate dynamic exchanges within covalent adaptable networks (CANs). Polybenzoxazines, specifically, have shown considerable potential in generating vitrimers through thermally induced transesterification reactions catalyzed internally by tertiary amines. This study aims investigate the chemical complexities benzoxazine vitrimers. To achieve this, model molecules using various phenolic acids and amino-alcohol derivatives were synthesized precursors. structure these was fully elucidated nuclear magnetic resonance (NMR). Differential scanning calorimetry (DSC) rheology experiments evidenced accelerated network formation precursors due presence aliphatic −OH groups. Thermogravimetric analysis coupled with microcomputed gas chromatography (TGA-μGC) used provide evidence reactions. results showed that spatial proximity between amine hydroxyl groups significantly enhances rate exchange, attributed neighboring group participation (NGP) effect. Interestingly, kinetic complementary NMR techniques revealed thermal latency toward its opening is needed trigger exchange. highlights crucial role steric hindrance basicity promoting exchange an system.
Language: Английский
Citations
10
International Polymer Processing, Journal Year: 2025, Volume and Issue: unknown
Published: Jan. 20, 2025
Abstract Concerns about the effect on environment and non-renewable nature of plastics have sparked a substantial field study towards creation recyclable polymers. Vitrimers are potential class reusable polymers that recently attracted lot interest. Like conventional thermosets in strength, durability, chemical resistance, these materials offer added benefit being at end their useful life. Their structure, which includes dynamic covalent crosslinks to provide stability while enabling reprocessing, is credited with this special characteristic. We lay out an overview recent developments applications epoxy based vitrimeric by using different types adaptable networks (CANs) – single, dual triple paper attention design tactics make it easier create circular future. Covalent Adaptable Networks (CAN), novel polymer family can bridge gap between thermoplastics, emerged years uses chemistry crosslinked networks. The was enhanced 2011 Leibler colleagues when they introduced notion vitrimers, retain integrity network even after heating allow connections be reallocated within them associative exchange reactions. This review also demonstrates how vitrimer community paying need for sustainable material development demonstrating use biobased building blocks synthesis high-performing vitrimers. Having outlined primary characteristics commercialization vitrimers emphasized portray benefits self-healing, malleability, orthogonal processability, various shape memories along solutions synthetic materials.
Language: Английский
Citations
1
Polymer, Journal Year: 2025, Volume and Issue: unknown, P. 128180 - 128180
Published: Feb. 1, 2025
Language: Английский
Citations
1