Microscopic effect and mechanism of spray polyurea modifier on the asphalt binder: experimental characterization and molecular dynamics simulations

Polymer, Journal Year: 2024, Volume and Issue: unknown, P. 127807 - 127807

Published: Nov. 1, 2024

Language: Английский

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A review on boron nitride reinforced polyimide-based nanocomposites for high-temperature capacitive energy storage: Challenges and recommendations

Journal of Thermoplastic Composite Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 11, 2025

The adoption of polyimide-based materials for high temperature related applications is receiving increased attention from the research community, particularly high-temperature capacitive energy storage. Polyimide matrix material has illustrated its effectiveness in design and manufacturing polymer-based dielectric capacitors, owing to intrinsic characteristics. However, modifying structure characteristics widespread using inorganic filler. present study reviewed recent advances on enhancement nanocomposite properties boron nitride fillers From literature, it worth noting that remain promising improving dielectric, breakdown strength, thermal conductivity, stability response polyimide nanocomposites favourable capacitors application. Additionally, storage density charge-discharge efficiency nitride-reinforced relation strength conductivity were thoroughly discussed. In conclusion, current challenges, which are associated with fabrication characterization presented, as well recommendation future directions this developing field.

Language: Английский

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Chemical Recycling of Step-Growth Polymers Guided by Le Chatelier’s Principle

ACS Engineering Au, Journal Year: 2024, Volume and Issue: 4(5), P. 432 - 449

Published: July 15, 2024

Although step-growth polymers (SGPs) play a fundamental role in the plastics economy, contributing significantly to various facets of our daily life, their end-of-life management remains inadequately addressed. Chemical recycling SGP wastes, involving depolymerization followed by repolymerization, emerges as promising solution toward achieving circular economy. The SGPs is usually dynamic equilibrium with polymerization reactions, thus falling under system amenable Le Chatelier's principle. This perspective endeavors elucidate interplay between principle and chemical particular emphasis on guidance provided latter process. To this end, we have selected five conventional SGPs, namely, poly(ethylene terephthalate), polyamides, polycarbonates, polyurethanes, polyureas, representatives how alterations temperature, pressure, concentrations products or reactants, catalysts influence process SGPs. Additionally, proposes several potential strategies for applying

Language: Английский

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High-Performance Poly(amide-urea) via a Nonisocyanate Route with Simultaneously Improved Strength and Toughness

ACS Sustainable Chemistry & Engineering, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 27, 2025

Language: Английский

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Kinetic Study of the Ring‐Opening Polymerization of Diaziridines With Diamines

Macromolecular Reaction Engineering, Journal Year: 2025, Volume and Issue: unknown

Published: March 26, 2025

Abstract Polyureas spread their portfolio of applications in the last years due to unique mechanical and chemical properties. However, scale‐up required sustain this growing interest brings about safety sustainability concerns. First, possibility avoiding use isocyanates is compelling. To fill gap, an innovative isocyanate‐free route has been proposed based on step‐growth polymerization a diazirine with aliphatic diamine. Still, selection environmentally friendly solvent proper understanding kinetic mechanism remain as open points be urgently cleared favor adoption appealing route. For reason, present work pretends establish safe for N,N’‐(hexane‐1,6‐diyl)bis(aziridine‐1‐carboxamide) evaluation its Hansen solubility parameters. Then, systematic analysis performed at different stoichiometric ratios hexamethylenediamine diaziridine (r) develop model co‐polymerization, by deriving rate constant associated reaction dependence from temperature. With aid model, polymer microstructure can reliably predicted tuned acting process conditions r, thus expanding new class materials.

Language: Английский

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Sustainable Bio-based Polyurethane Adhesives Utilizing PPG2000 and Renewable Polyols: Synthesis, Characterization, and Mechanical Properties

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: April 2, 2025

Developing high-performance, sustainable adhesives for automotive, aerospace, and industrial applications remains a major challenge due to the inherent trade-off between mechanical strength thermal stability in bio-based materials. While previous studies have explored polyurethane (PU) adhesives, achieving superior adhesion durability challenging when compared petroleum-based counterparts. This study presents novel adhesive system utilizing polypropylene glycol (PPG2000), isophorone diisocyanate (IPDI), renewable polyols (isosorbide-derived polyols, diglycerol, glycerol). The were synthesized via controlled one-shot polymerization process with 4-tert-butylphenol as an end-capping agent, enabling precise modulation of crosslink density molecular architecture. Fourier-transform infrared (FT-IR) spectroscopy confirmed complete urethane bond formation, isocyanate group (NCO%) titration validated stoichiometric conversion. Gel permeation chromatography (GPC) revealed distinct weight distributions, which influence performance by affecting density, elasticity, depending on polyol structure. Thermal analysis showed that isosorbide-derived formulations exhibited up 25°C higher degradation onset temperature 10°C increase glass transition (Tg) adhesives. Meanwhile, containing diglycerol glycerol demonstrated 39% shear (32.5 MPa) 77% improved impact resistance (36.8 relative reference system, attributed optimized segmental mobility crosslinking effects. work establishes strategic framework designing while acknowledging limitations such potential variability raw material sources suggesting future research into long-term environmental performance, not only surpasses conventional systems but also aligns principles green chemistry innovation. These findings offer pathway next-generation structural applications.

Language: Английский

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The Latest Advances in Mechanically Robust Self‐Healing Polyurea Based on Dynamic Chemistry

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

Abstract Polyureas are widely used in many fields such as civil, industry, and defense due to their excellent performance structural adjustable properties. The development of self‐healing polyurea materials with high strength toughness, key connotations advanced applications, is both fascinating challenging because these properties associated conflicting features, making it difficult optimize contradictory a single material. In this review, the relationship between structure discussed, design strategy networks based on dynamic interactions that allow for balancing mechanical repairability delineated from molecular point view. Lastly, summary potential applications sensing, protective coatings, recycling, well possible future challenges, presented.

Language: Английский

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Polyurea Adhesives & Coatings

Published: May 3, 2025

Language: Английский

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3D-Printed Cellulose Aerogels Minimally Cross-Linked with Polyurea: A Robust Strategy for Tissue Engineering

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: May 28, 2025

Cellulose and its derivatives are increasingly explored in biomedical applications due to their biocompatibility, biodegradability, mechanical performance. In regenerative medicine, aerogel scaffolds with tunable morphology composition highly valued for ability support tissue regeneration. Three-dimensional (3D) printing offers an effective method fabricate aerogels hierarchical pore structures, comprising interconnected macropores mesopores, that crucial engineering. For clinical use, 3D should ensure the structural integrity of printed structures achieve a resolution allows customization. this work, X-aerogel technology, implemented via polyurea cross-linking, was applied 3D-printed cellulose thereby expanding potential both technologies. Specifically, methylcellulose (MC) MC doped bacterial nanofiber (MCBCf) gels were cross-linked aliphatic polyurea, yielding, after supercritical drying, corresponding (X-MC X-MCBCf) aerogels. Elaborate characterization ATR-FTIR, XPS, ToF-SIMS, N2 porosimetry, He pycnometry, SEM confirmed formation on biopolymer framework, reinforcing structure improving properties without altering or textural characteristics materials. A significant outcome cross-linking is long-term stability X-MC X-MCBCf water, contrast native counterparts, capacity absorb water up 1800% w/w within only 2 h. Preliminary biological evaluation materials, including vitro (cell compatibility, hemolytic activity), ovo (HET-CAM), vivo (A. salina model) tests, showed good cell viability, blood safety living organisms. From fundamental materials perspective, most important finding work disproportionally high physiological environments, achieved minimal (almost undetectable) amount polyurea. application standpoint, findings study, collectively, position these as sustainable promising candidates engineering scaffolds.

Language: Английский

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Preparation and Performance Study of Polyurea (Pua) Modified Asphalt

Published: Jan. 1, 2025

Language: Английский

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