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Synergistic Dual Dynamic Bonds in covalent adaptable networks

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CCS Chemistry 2024年第1期6卷 41-56页

作者： Jun Zhao Zhaoming Zhang Chunyu Wang Xuzhou Yan School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai

covalent adaptable networks(CANs),comprising polymer networks crosslinked by dynamic covalent bonds(DCBs),have garnered considerable attention as sustainable *** the stress relaxation of CANs is essential for controlling their viscoelastic *** unexpected acceleration of stress relaxation has been observed in CANs containing dual dynamic *** dynamic behavior of the second dynamic bonds can accelerate stress relaxation and lower the relaxation activation energy of dual dynamic CANs compared to analogous CANs that rely on only one type of *** findings complement current approaches that utilize catalysts or adjust network *** this minireview,we summarize the synergistic acceleration effects in various CANs containing dual dynamic *** classify these effects based on the second dynamic bonds,including noncovalent bonds,mechanical bonds,and the second *** also discuss the mechanisms behind this ***,we highlight the challenges and offer perspectives on harnessing the synergistic effects of these dual dynamic systems to expand the chemistry and applications of CANs.

关键词： covalent adaptable networks dynamic covalent bonds dynamic materials stress relaxation synergistic effect

Dynamic Oxime-Urethane Bonds, a Versatile Unit of High Performance Self-healing Polymers for Diverse Applications

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Chinese Journal of Polymer Science 2021年第10期39卷 1281-1291,I0006页

作者： Luzhi Zhang Zhengwei You State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Shanghai Belt and Road Joint Laboratory of Advanced Fiber and Low-dimension Materials(Donghua University)College of Materials Science and EngineeringShanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineDonghua UniversityShanghai 201620China

Oxime-urethane bond featuring with high reversibility even at room temperature and multiple reactivity is an emerging dynamic covalent bond,and has shown great potential for self-healing polymers,which are one of the most attractive development directions for next generation of polymeric *** this review,recent progresses on the oxime-urethane-based self-healing polymers,including their designs and applications in diverse fields such as biomedicine,flexible electronics,soft robots,3D printing,protective materials,and adhesives,are summarized,and outlooks on the future development of this field are discussed.

关键词： Self-healing Dynamic covalent bonds Polyurethane covalent adaptable networks Metal coordination

Flexible,thermal processable,self-healing,and fully bio-based starch plastics by constructing dynamic imine network

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Green Energy & Environment 2024年第10期9卷 1610-1618页

作者： Xiaoqian Zhang Haishan Zhang Guowen Zhou Zhiping Su Xiaohui Wang State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou510640China

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable *** is desirable for fabricating bioplastic due to its abundance and renewable ***,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread *** overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base *** strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature(T_(g)=20.15℃).Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility(elongation at break=45.2%)and waterproof capability(water contact angle=109.2°).Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical *** work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.

关键词： Bioplastic covalent adaptable networks Schiff base chemistry Thermal processability Self-healing

A weak but inert hindered urethane bond for high-performance dynamic polyurethane polymers

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Chinese Chemical Letters 2024年第5期35卷 238-243页

作者： Fangzhou Wang Wentong Gao Chenghui Li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China

covalent adaptable networks(CANs),which share the properties of both thermosets and thermoplastics at the same time,are desirable for many *** bulky substituents is a feasible way to design dynamic covalent bonds for constructing CANs,as evidenced by the successful implementation in CANs based on hindered urea bonds(HUBs).However,the dynamicity induced by introducing bulky substituents always come with low bond energy,resulting in low mechanical strength and poor stability of the ***,we designed a novel hindered urethane bond,which is weak in thermodynamic(K_(eq)=1701.23 L/mol at 25℃)and inert in kinetic at low temperature,but stable in thermodynamic(K_(eq)=1.54×10^(4) L/mol at 100℃)and active in kinetic at high temperature(k_(-1)=0.105 h^(-1) at 80℃ and 0.315 h^(-1) at 120℃).As a result,the polyurethane based on it exhibits high mechanical properties(with Youngs’modulus of 1011±29MPa and flexible modulus reached 1833±50MPa)and excellent reversibility(can be reprocessed at 60℃ under 100 kPa in 30 min and completely healed at 40℃ in 10 min).Moreover,unlike to many CANs based on hindered urea bonds,our dynamic polyurethanes are highly stable in humid environment or even water solutions due to the slow hydrolysis *** highperformance dynamic polyurethane polymers are attractive for many applications.

关键词： covalent adaptable networks Urethane bond Kinetics Thermodynamics

Reshapeable,rehealable and recyclable sensor fabricated by direct ink writing of conductive composites based on covalent adaptable network polymers

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International Journal of Extreme Manufacturing 2022年第1期4卷 94-107页

作者： Xu He Yuchen Lin Yuchen Ding Arif M Abdullah Zepeng Lei Yubo Han Xiaojuan Shi Wei Zhang Kai Yu Department of Mechanical Engineering University of Colorado DenverDenverCO 80217United States of America Department of Chemistry University of Colorado BoulderBoulderCO 80309United States of America School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080People’s Republic of China

covalent adaptable network(CAN)polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable,rehealable,and fully recyclable *** the other hand,3D printing as a deterministic manufacturing method has a significant potential to fabricate electronics with low cost and high design *** this paper,we incorporate a conductive composite consisting of polyimine CAN and multi-wall carbon nanotubes into direct-ink-writing 3D printing to create polymeric sensors with outstanding reshaping,repairing,and recycling *** developed printable ink exhibits good printability,conductivity,and *** conductivity of printed polyimine composites is investigated at different temperatures and deformation strain *** shape-reforming and Joule heating-induced interfacial welding effects are demonstrated and ***,a temperature sensor is 3D printed with defined patterns of conductive pathways,which can be easily mounted onto 3D surfaces,repaired after damage,and recycled using *** sensing capability of printed sensors is maintained after the repairing and ***,the 3D printed reshapeable,rehealable,and recyclable sensors possess complex geometry and extend service life,which assist in the development of polymer-based electronics toward broad and sustainable applications.

关键词： bond exchange reactions polyimine covalent adaptable networks direct ink writing rehealable electronics recyclability

Cooperative Chemical Coupling and Physical Lubrication Effects Construct Highly Dynamic Ionic covalent adaptable Network for High-Performance Wearable Electronics

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CCS Chemistry 2023年第5期5卷 1096-1107页

作者： Lijie Sun Hongfei Huang Qingbao Guan Lei Yang Luzhi Zhang Benhui Hu Rasoul Esmaeely Neisiany Zhengwei You Meifang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringInstitute of Functional MaterialsResearch Base of Textile Materials for Flexible Electronics and Biomedical Applications(China Textile Engineering Society)Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineDonghua UniversityShanghai 201620 Key Laboratory of Clinical and Medical Engineering School of Biomedical Engineering and InformaticsNanjing Medical UniversityNanjing 211166 Department of Materials and Polymer Engineering Faculty of EngineeringHakim Sabzevari UniversitySabzevar ***

covalent adaptable networks(CANs),which combine the benefits of traditional thermosets and thermoplastics,have attracted considerable *** dynamics of reversible covalent bonds and mobility of polymer chains in CANs determine the topological rearrangement of the polymeric network,which is critical to their superior features,such as self-healing and ***,we introduce an ionic liquid to dimethylglyoximeurethane(DOU)-based CANs to regulate both reversible bond dynamics and polymer chain mobility by cooperative chemical coupling and physical ***-molecule model experiments demonstrated that ionic liquids can catalyze dynamic DOU bond *** liquid also breaks the hydrogen bonds between polymeric chains,thereby increasing their *** a combined result,the activation energy of the dissociation of the dynamic network decreased from 110 to 85 kJ mol^(−1).Furthermore,as a functional moiety,the ionic liquid imparts new properties to CANs and will greatly expand their *** example,the consequent conductivity of resultant ionic CAN(iCAN)has demonstrated a great power to build high-performance multifunctional wearable electronics responsive to multiple stimulations including temperature,strain,and *** study provides a new design principle that simultaneously uses the chemical and physical effects of two structural components to regulate material properties enabling novel applications.

关键词： covalent adaptable networks polyurethane self-healing recycling ionic skin

A Strong and Rigid Coordination adaptable Network that Can Be Reprocessed and Recycled at Mild Conditions

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CCS Chemistry 2022年第12期4卷 3781-3797页

作者： Wen Li Hong-Qin Wang Wen-Tong Gao Zhangxia Wang Pan Xu Haibo Ma Cheng-Hui Li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023 School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167 Jiangsu Key Laboratory of Vehicle Emissions Control School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023

The investigation of covalent adaptable networks(CANs)is expanding rapidly due to the growing demand for sustainable materials,as CANs show thermoset-like behavior and yet can be reprocessed,recycled,and ***,most of the CANs reported so far have a trade-off between mechanical strength and reversible properties and often show performance reduction after reprocessing and/or ***,we designed and synthesized a coordination adaptable network(CoAN)by crosslinking low-molecular-weight monomers with abundant coordination *** to its excellent variable-stiffness property,leading to high stiffness at ambient conditions and low viscosity at elevated temperature,the as-prepared CoAN showed high mechanical rigidity but could be reprocessed rapidly and recycled at mild *** reprocessing or recycling,the mechanical properties of the samples showed no performance reduction,compared with a pristine *** functional theory calculations showed that free thiol ligands played a key role in reducing the activation energy for bond *** used as binders for composites,the embedded carbon fibers could be recycled rapidly and still maintain the original *** material also showed temperature-sensitive dielectric and conductive properties due to the release of metal ions upon ***,such performances are superior among the CANs reported previously.

关键词： covalent adaptable networks coordination bond recycle reprocess self-healing