ACS Applied Energy Materials
·
2021
·
IF 6.024
Li-Mei Peng,Zhao Xu,Wei-Yu Wang,Xing Zhao,Rui-Ying Bao,Lu Bai,Kai Ke,Zheng-Ying Liu,Ming-Bo Yang,Wei Yang
Solid–liquid phase change materials (PCMs) are widely used in heat management. However, the requirement of no leakage of solid–liquid PCMs during phase transition and suitable deformability at evaluated temperature are contradictory when PCMs are used as thermal interface materials (TIMs). Vitrimer, a kind of material that combines with the advantages of both thermoplastics and thermosets, may be a solution. Herein, polyethylene wax vitrimer (PEWV) is prepared through the dioxaborolane exchange reaction for TIMs with leakage-proof and high-energy-storage ability. Microphase separation occurs between highly cross-linked skeleton and slightly cross-linked chains, which solves the leakage problem of polyethylene wax. Simultaneously, PEWV can achieve a high latent heat storage capacity of about 121.0 J g–1, about 74% of that of PEW, owing to the negligible effect of dynamic cross-linking on the crystallization of PEW. Meanwhile, PEWV can be plastically deformed and tightly adhered to the rigid surface under a slight external force at the phase change temperature, filling the gap at macro- and microscales for improving the heat transfer efficiency. The composites of PEWV and thermal conductive filler show more excellent performance as TIMs than commercial thermal conductive pads. PEWV with no leakage, excellent plasticity, and high latent heat storage capacity provides great application potential in heat storage and thermal interface management.
研究领域:
材料科学
·
热管理技术
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DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2026
·
IF 5.4
Runying Gao,Ran Mei,Birong Zeng,Wei Lin,Guorong Chen,Weiang Luo,Yiting Xu,Conghui Yuan,Lizong Dai
Employing carbon dots as the crosslinking agent for polyvinyl alcohol (PVA) allows the formation of multiple interactions between carbon dots and PVA. • The fragmented PVA/BP-CDs0.3 vitrimer film can be reprocessed via hot pressing at 150 °C for 2 h to regenerate an intact film. • The phosphorus species present on the surface of carbon dots simultaneously imparts good flame-retardant properties to the composite PVA vitrimer film with a 27.7% LOI and VTM-0 rating. • Compared with pure PVA, the tensile strength of the PVA/BP-CDs0.3 composite vitrimer film is increased by approximately 122%, while its Young's modulus is enhanced by about 35%. The design of crosslinked network is important for polyvinyl alcohol (PVA) to overcome the disadvantages in weak mechanical strength and water resistance. Herein, the strategy of using carbon dots as PVA crosslinking agent was proposed. The carbon dots made of phenylboric acid and phosphoric acid could generate the combination effect of nano-enforcement and dynamic exchangeable network in PVA because of the multiple interactions between PVA and carbon dots. In addition, the existence of phosphorus element on the carbon dots could be expected to synchronously endow the composited PVA film with flame retardancy. The experimental results showed that compared to pure PVA, the tensile strength of PVA/BP-CDs0.3 significantly increased from 63.89 MPa to 142.03 MPa, and the Young's modulus increased from 1.56 GPa to 2.10 GPa, respectively. The limiting oxygen index (LOI) and vertical burning rating of PVA/BP-CDs0.3 were also improved to be 27.7% and a VTM-0 grade. Furthermore, it retained a mechanical strength of 16.05 MPa after being immersed in water for 15 days, indicating an excellent water resistance. It was worth noting that the shredded PVA/BP-CDs0.3 film could be reprocessed under hot-pressing with the condition of 150 °C and 2 h, forming a complete film. This work is helpful to provide new insights for the development of functional and recyclable PVA composite vitrimer film. Download: Download high-res image (138KB) Download: Download full-size image
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Xingyu Liu,Xuanyue Hong,Yi Wang,Jun Lin,Jujun Ruan,Shaojian He
Currently, the primary limitation hindering the sustainable application of epoxy (EP) vitrimers lies in the inherent trade-off among high mechanical performance, efficient recovery capability and mild recycling conditions. To address this challenge, we designed an EP polymer that leverages the high rigidity of imine bonds and the rapid bond exchange of boronic ester linkages, simultaneously achieving high mechanical performance, efficient recovery capability, and mild-condition recyclability. The resulting material exhibits a high mechanical strength of 78.6 MPa, excellent recovery efficiency (>90% after two cycles of crushing and then hot-pressing at 130°C), and mild solvent-assisted closed-loop recycling. Furthermore, carbon fiber-reinforced polymers (CFRPs) fabricated with this EP vitrimer demonstrated complete degradation in (solvent) within 30 min at 50°C. The reclaimed carbon fibers (CF) retained pristine surface morphology and preserved 96% of their original mechanical properties, enabling highly efficient and non-destructive recovery. These findings highlight the potential of this EP vitrimer system, offering a promising strategy for the sustainable development of polymer materials.
研究领域:
高分子科学
·
材料工程
·
可持续化学
·
机械工程
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 31
·期 3
·1-13
·
IF 2.6
Chi Yongbo,Li Mingzhuan,Chen Tongzhou,Liu Xingyao,Xie Ximing,Xu Jian
Epoxy resin is difficult to recycle and degrade due to its permanently crosslinked network structure after complete curing. Therefore, the traditional treatment of epoxy resin waste is landfill or incineration, which not only causes environmental pollution and the waste of resources but also limits its secondary applications. To solve this problem, a repairable and recyclable epoxy vitrimer, composed of bisphenol A glycidyl ether, glutaric anhydride, and carboxy-terminated polyether, was prepared in this work. The polyether-modified epoxy vitrimer showed good mechanical properties with a flexural strength of 69.2 MPa and a fracture toughness of 9.17 MJ/m 3 . Dynamic ester exchange reactions at elevated temperatures enable the epoxy vitrimer to achieve network rearrangement. As a result, the epoxy vitrimer exhibits excellent self-healing (complete healing of cracks within 5 min), shape memory, and recycling properties (75% retention of flexural strength). Furthermore, the prepared carbon fiber-reinforced vitrimer composites can be degraded by ethylene glycol for effective recycling of carbon fibers. Herein, the fracture toughness and reparability of the epoxy vitrimer were effectively improved by introducing the carboxy-terminated polyether into the crosslinked network, which has practical value for extending service life and reducing energy consumption in its engineering applications.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2024
·Vol. 31
·期 3
·1-12
·
IF 2.6
Zhang Qinghua,Li Mingzhuan,Feng Peifeng,Meng Luoli,Jian Xigao,Xu Jian
Carbon fiber thermoset composites pose significant challenges due to their inability to be reprocessed and the difficulties in recycling carbon fibers. Vitrimer materials with reversible dynamic covalent bonding offer a promising solution for the degradation of thermosetting resins and the recycling of carbon fibers. However, their practical application is limited by inability to quickly release stresses from deformation and long degradation times. To address these limitations, this study presents a novel vitrimer material based on free amine-catalyzed aromatic dynamic disulfide exchange. The dynamic disulfide exchange network, catalyzed by free amines, exhibits rapid stress relaxation, with a relaxation time of only 14 s at 180 °C. This exceptional dynamic exchange capability grants the vitrimer material outstanding self-healing properties, shape memory functionality, and recycling performance. Moreover, the higher concentration of disulfide bonds and the generation of small molecules increase the susceptibility of the crosslinked network to thiol degradation, resulting in resin degradation within 5 h. Additionally, this research successfully applies the vitrimer material as a matrix to prepare carbon fiber composites with exceptional mechanical properties. Furthermore, by degrading the resin matrix, effective recycling of carbon fibers is achieved, contributing to sustainable practices in the automotive and aerospace industries.
研究领域:
材料科学
·
可持续发展
·
化学工程
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DOI
高影响因子
POLYMER
·
2020
·
IF 4.231
Shuaipeng Wang,Na Teng,Jinyue Dai,Jingkai Liu,Lijun Cao,Weiwei Zhao,Xiaoqing Liu
Fabrication of mechanically robust and catalyst-free vitrimers is of great importance, but often challenging. Herein, a facile strategy to achieve this goal by incorporation of intramolecular hydrogen bonds into the dynamic covalent network is demonstrated. Specifically, glycidyl methacrylate (GMA) is reacted with bio-renewable malic acid (MA) to generate a UV-curable resin containing ester linkages. On account of the proximity between the α -carbonyl and β -hydroxyl groups in MA, six-membered-ring intramolecular hydrogen bonds ( O-H⋯O=C ) are formed in the cross-linked network. This formation of intramolecular hydrogen bonds endows the network with enhanced and outstanding mechanical properties , showing tensile strength and Young's modulus of 117.7 MPa and 3.66 GPa, respectively. Meanwhile, the network is able to efficiently alter its topology without external catalyst through transesterifications reactions at high temperatures. We attributed this phenomenon to the presence of intramolecular hydrogen bonds which make the α -carbonyl carbon more positive and be more reactive towards nucleophilic attack, and thus facilitate the transesterification reaction. This work suggests a promising route to achieve catalyst-free thermosets with superior mechanical performances, good self-healing ability and reprocessability.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Wei Zhao,Zihao Feng,Zhenhua Liang,Yanfeng Lv,Fukang Xiang,Chuanyin Xiong,Chao Duan,Lei Dai,Yonghao Ni
Vitrimer, the third category of polymer materials, combines the properties of traditional thermosets and thermoplastics and has gained much interest from industry since the first report in 2011. Currently, many researchers focus on the exploration of new chemistry for novel vitrimer synthesis but pay less attention to the fabrication of vitrimer composites based on known vitrimer systems. The latter can not only largely decrease the cost of vitrimers but also provide a facile way to increase the variety of vitrimer-based materials and extend the applications of vitrimers in different fields. In this study, we developed a new class of vitrimer composite using polycarbonate as a matrix and natural cellulose paper as the reinforcing framework for the first time. The resultant materials possess exceptional mechanical properties and great thermal/chemical stability, simultaneously exhibiting a series of smart properties, such as shape-memory, reshaping, self-healing, and reprocessing. Noteworthily, the two main components of the resultant materials, polycarbonate and natural cellulose, can be easily recycled under mild conditions; thus, these new vitrimer composites qualify as novel green and sustainable materials.
研究领域:
材料科学
·
绿色化学
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产品关联
DOI
PubMed
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 5
·2879-2888
·
IF 5.044
Li Chang,Ju Benzhi,Zhang Shufen
The synthesis of the first cellulose-based vitrimer is described. Dynamic ester bonds were responsible for the dynamic properties of carboxymethyl cellulose (CMC)-based vitrimer. The addition of suitable catalyst and glycerol in the vitrimer formulations was crucial for the reprocessability of these materials. Thermogravimetric and dynamic mechanical analyses tensile strength tests were performed to investigate the effect of the catalyst and glycerol on the thermal stability and mechanical properties of the materials. A minimum amount of 5 mol% of 1,5,7-triazabicyclo[4.4.0]dec-5-ene with respect to the carboxyl group content was required to maintain reprocessability by hot press. The CMC vitrimer exhibited good reprocessability and shape memory ability. Our work demonstrates that cellulose, the most abundant bio-resource on the planet, can be a promising raw material for bio-based vitrimer due to its excellent renewability and low cost. Graphic abstract
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Chang Li,Benzhi Ju,Shufen Zhang
Cellulose-based vitrimers were prepared using a crosslinkable macromolecular plasticizer and acetylated carboxymethyl cellulose via twin-screw extrusion. The cellulose-based material was toughened by the entanglement between the macromolecular plasticizer segments, and the exudation of the plasticizer was avoided by crosslinking. The prepared materials exhibited excellent hydrophobicity and shape memory properties. The plasticizer was evidently effective, and the reprocessing was completed at 130 °C within 15 min. The materials could be reprocessed at a lower temperature over a short period of time without any obvious degradation. After reprocessing three times, the material performance did not decrease significantly, thus showing good potential for regeneration and recycling.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
PubMed
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2023
·
IF 6.9
Chang Cong,Jixiao Wang,Guangyu Xing,Zhan Wang,Sicheng Yuan,Zhi Wang
Polymeric coatings , widely used in large-scaled outdoor applications including solar energy collection, metal protection and so on, are limited by short service life caused by degradation and structural damage due to constant exposure in air and external force. Here, oxidized carbon black (OCB)/epoxy vitrimer (EV) composite without catalysts, dispersants and pre-heating was prepared by facile solvent mixing method. The addition of OCB improved the stress relaxation rate of the composite and endowed high solar absorptance (α) at 94.57% and solar thermal efficiency (η) at 93.28%. The efficiency of remote and local photothermal-stimulated healing for micro scratches of the composite coating was as high as 95.08%. And the macroscopic damage repairing which was rarely reported can be about 100% by a novel photothermal patching method. Meanwhile, the composites also have behaviors of shape memory, reusability and ion transfer barrier performance. Overall, based on the advantages of facile preparation, cheap raw materials, high solar absorptance and solar thermal efficiency and excellent remote and local healing efficiency, the OCB/EV composite coatings have potential applications in solar energy harvesting and provides a new strategy for the local and contactless repair of polymeric coatings used in outdoor applications such as solar-energy collector, solar absorption systems and metal protection, especially for the repair of the macroscopic damage.
研究领域:
材料科学
·
能源工程
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Chang Cong,Jixiao Wang,Zhan Wang,Guangyu Xing,Zhi Wang
Epoxy vitrimers with thermal-healing ability are widely studied to prolong the service life of materials. But the conventional preparation and healing strategy, involving external catalysts, preheating, hot press or/and heating the entire coating, are not applicable for the large-scale applications. In this work, a room-temperature brushable oxidized carbon black (OCB)/epoxy vitrimer composite based on dynamic transesterification reaction with excellent protective performance and localized photothermal-healing was prepared by solvent method. No external catalysts, preheating and hot press was needed in the preparation process. The experimental results demonstrate that the composite coatings exhibited an excellent metal protective performance. The effective non-contact local photothermal-healing can be achieved in 20 Min., and the scratch width can apparently narrow over 95 % and the impedance moduli of the composite coatings can be recovered from 263 Ω·cm 2 to above 10 8 Ω·cm 2 . The OCB/epoxy vitrimer composite coating, combining ideal metal protective performance with non-contact local photothermal-healing performance, has great promise for many practical applications in large-scale, such as metal protection and solar-energy collector.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2023
·
IF 5.3
Zhang Yongjie,Lin Zichun,Li Xiaopei,Li Guangdong
Vitrimer uniquely simultaneously combines the opposed thermoset-like properties (mechanical properties, durability, creep/solvent resistance) and thermoplastic-like properties (reshapability, recyclability), thus arousing great enthusiasms in the design, preparation and characterization of vitrimer. From a practical point of view, it is of great value to develop one-step and scalable synthetic procedures for high performance vitrimers. Starting from two highly available and non-expensive commodity materials, namely, ethylene acrylic acid copolymer (EAA) and triglycidyl isocyanurate (TGIC), a series of EAA-TGIC vitrimer materials with varying cross-linking degrees were prepared via a one-step, scalable and practical synthetic approach. Under mild melt compounding conditions, ring-opening of epoxy groups towards carboxyl groups in EAA occurred, resulting in cross-linking of EAA by dynamic β-hydroxyl ester covalent bonds. The formation of covalent cross-linking network in EAA-based vitrimer materials was proved by FTIR and swelling test. The thermo-mechanical, tensile, reprocessing and thermal properties of EAA-TGIC vitrimer were systematically studied. The results showed that EAA-TGIC vitrimer with high gel contents, and thus, excellent solvent resistances, were achieved. Tensile tests revealed that EAA-TGIC vitrimers exhibited premium mechanical properties with well-balanced rigidity and toughness and that the mechanical properties of recovered EAA-TGIC vitrimer remained almost unchanged compared to those of as-prepared EAA-TGIC vitrimer. This study offers a long sought-after solution for the cost-effective recycling of cross-linked polyethylenes and provides new possibilities for keeping difficult-to-recycle cross-linked polyethylenes in the circular loop.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）