Frontiers of Materials Science
·
2020
·Vol. 14
·期 2
·198-210
·
IF 1.747
Zhang Jinxing,Hu Kexing,Ouyang Qi,Gui Qilin,Chen Xiaonong
Good dispersibility of graphene in a medium or matrix is a critical issue in practical applications. In this work, graphene was functionalized using N-(4-hydroxyl phenyl) maleimide (4-HPM) via the Diels—Alder (DA) reaction by a one-step catalyst-free approach. The optimal reaction condition was found to be 90 °C for 12 h using dimethylformamide (DMF) as the solvent. FTIR, Raman spectroscopy, XPS and EDS proved that 4-HPM moieties were successfully grafted onto the surface of graphene. UV-vis and TGA confirmed that the grafting amount of 4-HPM was 3.75%–3.97% based on the mass of graphene. Functionalized graphene showed excellent dispersion stability when dispersed in common solvents such as ethanol, DMF, water, tetrahydrofuran and p-xylene. Meanwhile, functionalized graphene also exhibited pH sensitivity in aqueous due to the phenolic hydroxyls from the 4-HPM moieties. As a result of good dispersion stability and pH sensitivity, compared with graphene, functionalized graphene had better adsorption capacity for methylene blue (MB) from aqueous solution.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER BULLETIN
·
2017
·Vol. 74
·期 9
·3907-3922
·
IF 1.43
Wei Yanyan,Du Xiucai,Ma Xiaoyue,Zhao Kaifeng,Zhang Shiyu,Bai Yapeng
Highly cross-linked polyurethanes based on Diels–Alder (DA) reaction have high hardness but poor toughness. A modified polyurethane with three-furyl diol (TF) was synthesized innovatively to improve its mechanical properties. Three-furyl diol (TF) and hydroxyl terminated polyurethane IDI-TF were synthesized first. Then the reaction of IDI-TF with xylene bismaleimide (BMI) generates cross-linked polyurethane ITB-PU (its soft segment content is 11.5%). Finally, the properties of the polyurethane ITB-PU were characterized by a series of methods. It can be observed that the DA reaction occurred at 50.33 °C, the r-DA reaction at 69.55 °C. When heated at 80 °C for 6 h, the self-healing efficiency of the ITB-PU was 43.91% known from the tensile test, and cracks on it virtually disappeared seen from polarizing microscope (POM). When heat was preserved for 12 h, the self-healing efficiency can reach 80.02%.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 5
·474
·
IF 2.935
Yuting Zou,Liang Fang,Tianqi Chen,Menglong Sun,Chunhua Lu,Zhongzi Xu
Two issues are required to be solved to bring intrinsically self-healing polymer coatings into real applications: remote activation and satisfied practical properties. Here, we used MXene, a newly reported two-dimensional material, to provide an epoxy coating with light-induced self-healing capabilities and we worked to enhance the properties of that coating. The self-healing coatings had a reversible crosslinking network based on the Diels-Alder reaction among maleimide groups from bis(4-maleimidopheny)methane and dangling furan groups in oligomers that were prepared through the condensation polymerization of diglycidylether of bisphenol A and furfurylamine. The results showed that the delaminated MXene flakes were small in size, around 900 nm, and dispersed well in self-healing coatings. The MXene flakes of only 2.80 wt % improved greatly the pencil hardness of the coating hardness from HB to 5H and the polarization resistance from 4.3 to 428.3 MΩ cm−2. The self-healing behavior, however, was retarded by MXene flakes. Leveling agent acted a key part here to facilitate the gap closure driven by reverse plasticity to compensate for the limitation of macromolecular mobility resulting from the MXene flakes. The self-healing of coatings was achieved in 30 s by thermal treatment at 150 °C. The efficient self-healing was also demonstrated based on the recovery of the anti-corrosion capability. MXene flakes also played an evident photothermal role in generating heat via irradiation of near-infrared light at 808 nm and focused sunlight. The healing can be quickly obtained in 10 s under irradiation of near-infrared light at 808 nm having a power density of 6.28 W cm−2or in 10 min under irradiation of focused sunlight having a power density of 4.0 W cm−2.Keywords:self-healing;epoxy coating;MXene;Diels-Alder reaction;photothermal effect
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2021
·Vol. 60
·期 5
·794-802
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IF 0
Jiarui Yu,Nan Gao,Xiaowen Xie,Xing Xin,Zhanqi Li,Shuai Chen,Jingkun Xu
Thermally healing capability of cracks and defects is important and urgent for the safe operation and life extending of electric materials and devices. Here, by the combination of thermally driven reversible Diels–Alder (DA) interaction and in-situ chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT), a series of intrinsically conductive poly(3,4-ethylenedioxythiophene) (PEDOT)/DA composites possess intrinsically self-healing property under low-temperature (reverse DA reaction at 100°C; DA crosslinking at 60°C) stimulus were achieved. The crosslinking DA bonding reactions are multiple from the co-existence of pre-synthesized macromolecular polyurethane attached DA units (PU-DA) and 2,4-hexadiyne-1,6-diol (DADOL) in the films. PU-DA involved in the polymerization process of EDOT to endow PEDOT with outstanding solution-processability, uniform film making, and structural self-healing capability, while DADOL was added to enhance the cross bonding between polymer chains. This work will accelerate the research and application development of intrinsically self-healing conducting polymers for commercial capacitors, antistatic coatings, implantable, printable electronics, and so on. Graphical
研究领域:
材料科学
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电子工程
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产品关联
DOI
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2012
·Vol. 51
·期 5
·1205-1214
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IF 3.919
Xinjian Cheng,Cheng Peng,Daohong Zhang,Shuzheng Liu,Aiqing Zhang,Hui Huang,Jiansheng Lian
Novel cross-linked polyphosphazenes with remendable capacity have been synthesized through the Diels-Alder reactions. Their structure and properties were characterized by NMR, FT-IR, GPC, DSC, TGA SEM, and polarizing microscope. The process of Diels-Alder reaction (D-A reaction) and retro-Diels-Alder reaction (retro-D-A reaction) have been investigated by FT-IR, UV, and DSC. The cross-linked polyphosphazenes exhibited remendable capability only need a thermal treatment when they were cut by blade, any other treatments such as additional monomer or catalyst, surface treatment or pressure were not needed. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 44
·期 4
·1236-1244
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IF 3.069
Jianfeng Xu,Xiaomin Zhao,Feixiang Liu,Lun Jin,Guohua Chen
Functionalized graphene (G-MA) was prepared by a facile wet ball milling strategy, which achieved exfoliation and functionalization of graphite simultaneously. The G-MA showed excellent dispersion in water and polar solvents. Thus, a G-MA coating was prepared from G-MA in mixed solvents (H2O–ethanol) without binder or surfactant. The scanning electron microscope (SEM) images of the G-MA coating exhibited a smooth and flat surface. The G-MA coating showed a conductivity of 769 S m−1 at room temperature, and a big increase could be found at 2000 S m−1 after thermal treatment under 200 °C for 2 h, indicating the restoration of the conjugated structure via the reverse Diels–Alder reaction. This synthetic method of functionalized graphene offers a powerful strategy for the reversible modification of the graphene electronic properties, which may expand their usage.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 73
·46336-46343
·
IF 3.108
Chenting Cai,Yue Zhang,Xueting Zou,Rongchun Zhang,Xiaoliang Wang,Qiang Wu,Pingchuan Sun
The development of self-healing and recyclable crosslinked polymeric materials has drawn considerable attention in recent years. However, the bulk healing or remending speed is usually slow due to the high viscosity of high Mw polymers, and the low rate of thermal conduction from material surfaces into the central matrix. Herein, a rapid self-healing and recyclable high-performance crosslinked epoxy resin (ER)/graphene nanocomposite is reported by simultaneously incorporating thermally reversible Diels–Alder (DA) covalent bonds and multiple-responsive graphene into the ER matrix. Therefore, graphene in proximity to the DA crosslinkages can instantly trigger the retro-DA reactions by converting the absorbed energies (e.g. infrared light, microwave, etc.) into heat, and thus enables rapid self-healing and recycling. Furthermore, the well-dispersed graphene (<1 wt%) could significantly enhance the mechanical strength of the ER. In situ variable temperature solid-state NMR spectroscopy was used to monitor the reversible DA reactions at the molecular level, and the high healing and recycling efficiency of ER/graphene nanocomposites was well demonstrated by multiple approaches.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2018
·
IF 1.047
Xiaofei Wang,Kaifeng Zhao,Xiaowen Huang,Xiaoyue Ma,Yanyan Wei
Over time, automotive coating is bound to be damaged; therefore, it is necessary to give the coating a self-healing ability to make its performance even better. First, furfuryl glycidyl ether (FGE) was synthesized by epichlorohydrin and furfuryl alcohol. Then, furanyl-terminated resin FGE-T5000 was synthesized by polyether amine T5000 and FGE. Finally, 4,4′-diphenylmethane bismaleimide (BDM) was added to FGE-T5000 as a cross-linking agent to form a resin named FGE-T5000-BDM which has Diels–Alder (DA) bonds. The products were characterized by Fourier-transform infrared spectroscopy, proton nuclear magnetic resonance, differential scanning calorimeter, dynamic mechanical analysis, thermogravimetric analysis, optical microscope, tensile tests, and other tests. The results showed that FGE-T5000-BDM demonstrated thermally reversible self-healing property from 50°C to 150°C, and that the best temperature of the DA reaction was 80°C. The gel content of FGE-T5000-BDM was 98%. Also, the glass transition temperature and the initial temperature of the Retro-DA (r-DA) reaction were −58°C and 88°C, respectively. Moreover, the self-healing efficiency of FGE-T5000-BDM was up to 88% after staying at 80°C for 12 h. The innovation shown in this article was that the reversible covalent bonds (DA) were combined with the polyether amines, which produced the characteristics of self-healing. Its unique self-healing properties are useful in some areas, such as automobile coatings and other materials.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Tingting Lian,Shengchang Zhang,Qibin Xu,Kaixiang Wang,Bo Li,Xiangpu Qin,Mengjin Jiang,Pengqing Liu
The sustainability of epoxy thermosets (EPs) and EP-based composites is always limited by the evolution of internal microcracks and flammability. Herein, inspired by the drug release-delivery system for disease treatment, these symptoms of EP are solved efficiently by a multifunctional Diels–Alder (DA) release-delivery system. First, this novel system is fabricated by the cyclization reaction between the furan diene-containing phosphorus derivative and the maleimide dienophile. The resultant DA system is linked to the epoxy resin by the grafting reaction, thus ensuring its uniform dispersion. Being faced with the formation of inner microcracks, the maleimide dienophiles were released from the DA adducts under the mediated action of temperature and then were delivered to the targeted microcracks under the chemical potential difference derived from the variation of free volume. Then, the released maleimide molecules re-connect with the furan groups that existed near the microcracks to complete the repairing of the EP matrix. The skeletal structure of the EP was well preserved throughout the restoration process. Satisfactory flexural strength (105.5 MPa) and excellent crack-healing efficiency (104.5%) can be obtained for the modified EP. After three constant strain cycles, the stress retention rate can be readily maintained (more than 75%). In addition, due to the phosphorus–nitrogen synergistic flame-retardant effect from the DA system, not only the limited oxygen index of the DA-modified EP matrix can be improved to 27.5% but the lower peak release rate and lower total heat release are also observed compared with the unmodified EP.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2025
·Vol. 36
·期 3
·e70140
·
IF 3.4
Xianning Wang,Runqi Zhang,Lujia Xuan,Mengmeng Yu,Jianqing Mao,Gang Cheng,Jieqiong Yan,Hongzhen Wang
Covalent adaptable networks offer a viable approach for producing recyclable rubber materials. Nevertheless, the intricate synthesis process and insufficient mechanical strength limit their commercialization applications. In this study, the reinforced, thermal-healing, and recyclable chitosan/ethylene propylene diene rubber (CEF-CS) was synthesized using a solid-phase blending process via the Diels-Alder (D-A) reaction. Furfural modified chitosan (F-CS) was included as a reinforcing filler and dynamic cross-linking point into the network formed via the D-A reaction. The influence of F-CS content on the mechanical, thermomechanical, and thermal repair characteristics of CEF-CS composites was examined. The results showed that the CEF-CS composites exhibited certain mechanical strength and dependable repair capabilities. As the F-CS content increased, the tensile strength of CEF-CS composites initially rose and subsequently declined, reaching a peak of 5.1 MPa, which was 5.1 times more than the control without F-CS. The first healing efficiency of tensile strength exceeded 70%, whereas the second healing efficiency was above 60%. Moreover, the simple preparation procedure and enhanced mechanical strength facilitate the commercial utilization of recyclable rubber materials, which is crucial for addressing the environmental pollution issue associated with rubber materials.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2017
·
IF 3.386
Xue Dong,Rong-Tao Duan,Yan-Peng Ni,Zhi-Jie Cao,Li Chen,Yu-Zhong Wang
Retro-Diels-Alder reaction (rDA) has been widely used as a common modification approach for expanding functional applications of polymers. Especially, it has become an effective method of current cross-linking chemistry . With the goal of designing a cross-linkable PET-based copolyester toward flame retardancy and anti-dripping during combustion, dimethyl 5-(1,3-dioxo-3a,4,7,7a-tetrahydro-1 H -4,7-methanoisoindol-2(3 H )-yl) isophthalate (DMTMI) was incorporated as the functional co-monomer into PET chains via random transesterification polycondensation . Thermogravimetry-differential scanning calorimetry (TG-DSC) and rheological studies demonstrated the existence of cross-linking behavior at high temperature. By controlling the co-monomer content, expected flame retardancy was obtained, as illustrated by the results from the limiting oxygen index (LOI) and cone calorimetry. Furthermore, LOI values increased firstly and then decreased with the content of DMTMI increased, which was related to the existence of rDA reaction, and further proposed that a competitive relationship between the release of inflammable cyclopentadiene during rDA reaction and cross-linking behavior occurred in combustion. The hypothesis was verified through pyrolysis-gas chromatograph-mass spectrometry (Py-GC-MS).
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2019
·
IF 3.47
Chenguang Wang,Zhan Si,Xiaoping Wu,Wei Lv,Kang Bi,Xinghua Zhang,Lungang Chen,Ying Xu,Qi Zhang,Longlong Ma
In this paper, we study the production of aromatic hydrocarbons by co-feeding furans and methanol in a continuous flow fixed-bed reactor over HZSM-5 at 400–600 °C. The effects of reaction temperature, weight hourly space velocity ( WHSV ), furan to methanol molar ratio and time on stream on the product distribution were investigated. Maximum aromatics yield of 42.0% was obtained over HZSM-5 (Si/Al = 25) with 2-methylfuran (MF) to methanol molar ratio of 1:5 at 500 °C. With the methanol to MF molar ratio increasing from 0 to 5, the conversion of MF increased from 64.7% to 100.0% and the yield of coke decreased from 22.3% to 11.4%. In this process, dimethyl ether derived from methanol dehydration could promote the conversion of MF to aromatic hydrocarbons via Diels-Alder reaction. HZSM-5 with Si/Al ratio of 25 exhibited superior catalytic activity, indicating that strong acidity was necessary for the coupling conversion of MF and methanol. Additionally, the coupling conversions of 2,5-dimethylfuran (DMF), furfural (FF) and furfuryl alcohol (FA) and methanol were investigated. Functional groups of furan rings did not change the formation pathway of aromatic hydrocarbons but they have different constraints on the Diels-Alder reaction of furan ring with olefins .
研究领域:
化学工程
·
催化科学
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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）