Journal of Materials Chemistry A
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2014
·Vol. 2
·期 48
·20642-20649
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IF 0
Jinhui Li,Guoping Zhang,Libo Deng,Songfang Zhao,Yongju Gao,Kun Jiang,Rong Sun,Chingping Wong
Covalently bonded graphene oxide/polyurethane (GO/PU) composites with significant reinforcement and thermally healable properties were developed via in situ polymerization based on Diels–Alder (DA) chemistry. The PU prepolymer was prepared with GO, 4,4-diphenylmethane diisocyanate, and poly(tetramethylene glycol) and blocked by using furfuryl alcohol firstly. Then the prepolymer was cross-linked by using bifunctional maleimide via DA chemistry. SEM shows that the GO was dispersed uniformly in the PU matrix. The DA and retro-DA reactions were characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry separately. Tensile tests showed that with the incorporation of 0.1 wt% of GO, the tensile modulus of GO/PU composites increased from 9.80 MPa to 21.95 MPa, and the tensile strength and elongation at break of the GO/PU composites increased by more than 367% and 210%, respectively. Furthermore, the composites had thermally healable ability which was inspected by using an atomic force microscope and the strain–stress test. The healing efficiency of 78% on average was achieved which was determined by the recovery of breaking stress and a healing mechanism was tentatively proposed. Therefore, the covalently bonded self-healing GO/PU composites could be used as smart materials and structural materials.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Jinhui Li,Qiang Liu,Derek Ho,Songfang Zhao,Shuwen Wu,Lei Ling,Fei Han,Xinxiu Wu,Guoping Zhang,Rong Sun,Ching-Ping Wong
Wearable electronics with excellent stretchability and sensitivity have emerged as a very promising field with wide applications such as e-skin and human motion detection. Although three-dimensional (3D) graphene structures (GS) have been reported for high-performance strain sensors, challenges still remain such as the high cost of GS preparation, low stretchability, and the lack of ability to heal itself. In this paper, we reported a novel self-healing flexible electronics with 3D GS based on Diels–Alder (DA) chemistry. Furfurylamine (FA) was employed as a reducing as well as a modifying agent, forming GS by FA (FAGS)/DA bonds contained polyurethane with the “infiltrate-gel-dry” process. The as-prepared composite exhibited excellent stretchability (200%) and intrinsic conductivity with low incorporation of graphene (about 2 wt %), which could be directly employed for flexible electronics to detect human motions. Besides, the FAGS/DAPU composite exhibited lower temperature retro-DA response for the continuous graphene networks. Highly effective healing of the composites by heat and microwave has been demonstrated successfully.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
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2021
·
IF 7.664
Yuan Cao,Min Zhi Rong,Ming Qiu Zhang
To tackle the challenge of manufacturing highly filled composite materials via melt compounding and injection molding , the authors proposed a novel approach based on Diels-Alder (DA) chemistry. Polycaprolactone oligomers (PCL olig , M w = 2000 g/mol) were firstly crosslinked by DA bonds, and then the resultant network PCL olig -DA was also connected to maleimide functionalized Al 2 O 3 particles (Al 2 O 3 -M) via DA bonds. Upon being heated to the retro-DA reaction temperature, the covalent adaptable composite network exhibited low viscosity due to de-crosslinking, enabling melt processing and well dispersion of high-concentration fillers. During the subsequent cooling, the composite network was regained because of DA reaction, benefiting increase of the composite’s strength . Consequently, the contradictory requirements for molecular weight of matrix polymer under the circumstances, which had better to be as low as possible during the manufacturing but as high as possible in the ultimate composites, were skillfully satisfied.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
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IF 3.375
Qian Yan,Liwei Zhao,Qiancun Cheng,Tong Zhang,Bo Jiang,Yuanjun Song,Yudong Huang
In this paper, a thermally reversible self-healing polysiloxane elastomer based on Diels–Alder (DA) chemistry was successfully prepared via polysiloxane containing maleimide groups and furan rings. The hyperbranched polysiloxane (HPSis) containing furan rings and double bonds was synthesized and introduced to improve the mechanical strength of the polymer. The mechanical strength of polysiloxane without HPSis was only 0.20 MPa; however, it can be increased to 0.87 MPa with the introduction of HPSis. Since HPSis contain multi-furan rings required for thermally reversible reactions, the addition of HPSis would not have a negative effect on self-healing performance. The cracks on the surface of polysiloxane can be self-healed in a short time, and the self-healing efficiency of polysiloxane can achieve 85%. Moreover, flexible conductive composites poly(dimethylsiloxane)/carbon black (PDMS/CB) were fabricated by mixing the polysiloxane matrix with conductive filler carbon black (CB) and can be applied in wearable flexible sensors.
研究领域:
材料科学
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聚合物化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）