Polymers
·
2022
·Vol. 15
·期 1
·190
·
IF 4.967
Qian Sun,Xu Gao,Sai Wang,Rong-Yue Shao,Xin-Yu Wang,Jun-Feng Su
The aging and damage of artificial skin materials for artificial intelligence robots are technical problems that need to be solved urgently in their application. In this work, poly (vinylidene fluoride) (PVDF) fibers containing a liquid agent were fabricated directly as biomimetic microvasculars, which were mixed in a glycol–polyvinyl alcohol–gelatin network gel to form biomimetic self-healing artificial skin composites. The self-healing agent was a uniform-viscous buffer solution composed of phosphoric acid, acetic acid, and sodium carboxymethyl cellulose (CMC-Na), which was mixed under 40 °C. Microstructure analysis showed that the fiber surface was smooth and the diameter was uniform. SEM images of the fiber cross-sections showed that there were uniformly distributed voids. With the extension of time, there was no phenomenon of interface separation after the liquid agent diffused into the matrix through the fiber cavity. The entire process of self-healing was observed and determined including fiber breakage and the agent diffusion steps. XRD and FT–IR results indicated that the self-healing agent could enter the matrix material through fiber damage or release and it chemically reacted with the matrix material, thereby changing the chemical structure of the damaged matrix. Self-healing behavior analysis of the artificial skin indicated that its self-healing efficiency increased to an impressive 97.0% with the increase in temperature to 45 °C.Keywords:self-healing;artificial skin composite;fiber;healing agent
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Xiaoyu Zang,Zhengsong Qiu,Pengfei Guo,Hanyi Zhong,Xin Zhao,Tingbo Mu
Lost circulation is a critical technical challenge in the drilling and production process of underground oil and gas energy. In this study, a mechanically triggered release microcapsule for lost circulation control was designed and prepared with an in-situ polymerization using melamine, urea, formaldehyde, and diglycidyl ether of bisphenol A (healing agent) as raw materials. The structure and properties of the microcapsule were characterized by different techniques. The results show that the healing agent was successfully encapsulated by the resin shell, the median particle size (D50) of the microcapsules is 120.3 μm, and the thermal stability is excellent. The compatibility experiments show that the surface wettability and shear stability of the microcapsules are good in water-based drilling fluid. The compressive strength test reveals that the healing agent in the microcapsule is released and filled in the gap of the plugging zone under the contact pressure. The concentration of microcapsules and the size distribution of rigid particles are critical for the in-situ reinforcement effect. In addition, the fracture plugging performance of the microcapsule was studied. The results show that the pressure-bearing capacity of the plugging zone increases as the irregularity of the fracture surface increases. These findings indicate the microencapsulated healing agent is an effective lost circulation material (LCM), and provide a new technical idea for lost circulation control.
研究领域:
石油工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2021
·Vol. 8
·期 6
·065101
·
IF 1.62
Yueju Zhao,Xiwei Xie,Jinbiao Shi,Huaping Shan,Min Liu,Jie Liu,Jianhui Wang,Boyan Jia,Yongli Zheng,Qiang Chen,Chunfeng Zhao,Jilin Teng,Wenhua Miao
Due to the long-term operation of power grid and the interference of external uneven electric field environment, silicone rubber insulators are prone to aging and scaling, and their hydrophobicity and external insulation performance are easily affected. In order to solve this problem, a kind of silicone rubber insulator outer surface cleaning and repairing agent was prepared with self-made composite solvent and silicone as the main raw materials, supplemented by catalyst, surfactant and other additives. So as to achieve the dual effect of efficient cleaning and aging repair, improve its hydrophobicity and prolong its service life. Through hardness test, hydrophobicity test, SEM test, FT-IR test, EDS test, mechanical property test and aging test characterization, and comparing the cleaning effect of different cleaning methods, it is found that the cleaning effect of cleaning repair agent is the best. In addition, it is found that the hydrophobicity of insulator has been greatly improved, from HC4 to HC1, and the mechanical properties have also been improved. This is because after using the cleaning and repairing agent, the powdered layer on the insulator surface is removed, and more hydrophobic methylene (Si–(CH3)2) and methylene (Si–(CH3)3) are attached to the insulator surface, which reduces the -OH binding force between the insulator surface and water molecules. In addition, through the observation of the surface and cross-section micro morphology, it is found that the surface roughness of the insulator is greatly reduced and the micro cracks disappear after using the cleaning and repairing agent, which highlights a certain repairing effect. Finally, the aging test also shows that the cleaning repair layer has a certain durability.The results show that the cleaning and repairing agent can effectively clean and repair the aged insulator, improve its anti- pollution flashover ability and prolong the service life of silicone rubber insulator.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2015
·Vol. 6
·期 40
·7100-7111
·
IF 5.52
Chunmei Li,Jiaojun Tan,Hui Li,Dezhong Yin,Junwei Gu,Baoliang Zhang,Qiuyu Zhang
An innovative, rapid and efficient route is developed to fabricate ene loaded microcapsules via a thiol–isocyanate click reaction based on a hydrolyzed poly(glycidyl methacrylate) (PGMA) particle stabilized oil-in-water Pickering emulsion. The whole process for the reaction only requires 10 min, opening up a new, time-saving and energy-efficient strategy. The oil droplets contain isophorone diisocyanate (IPDI), trimethylolpropane tris(3-mercaptopropionate) (TMMP) and 1,3,5-tri-2-propenyl-1,3,5-triazine-2,4,6 (1H, 3H, 5H)-trione (TTT), in which IPDI and TMMP are subsequently catalyzed by triethylamine (TEA) to produce a polythiourethane network, forming microcapsules. From scanning electron microscopy (SEM) and optical microscopy (OM), the resulting microcapsules are in good spherical shape and their outer surface is coated with a compact PGMA particle layer. The mean diameter of the TTT loaded microcapsules decreases from 238.8 to 110 μm with increasing the particle stabilizer concentration. Solid-state 13C NMR measurement proves that almost no side reactions exist in the base-catalyzed thiol–isocyanate reaction. Moreover, the core content (up to 67.8%) and the thickness of the shell wall (8–36 μm) can be adjusted by the feeding amount of core materials. These microcapsules with an outer PGMA layer disperse well and maintain their integrity in the epoxy coating, and no agglomeration is observed. Even though being encapsulated, the core ingredient maintains high reactivity as its raw version and exhibits favorable healing capability. Furthermore, besides TTT, the proposed method is versatile and applicable to the encapsulation of SR833S and diallyl phthalate.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Qingyuan Ma,Hongwei He,Wenwen Yu,Jianjun Xu,Quanxin Xu,Jiaqi Xue,Yushi Jin,Rong Zhu,Chen Han,Zhengkun Wang,Chen Cui,Jie Ma,Fuyong Liu,Heng Zhang,Huayun Du
Highly efficient regeneration of the aging SBS modified bitumen (SMB) is crucial for promoting the achievement of low-carbon development goals. Restoring the structure or performance of the aged SBS is the focus of the present work. Many studies have proved that the high temperature performance of aging SMB is deteriorated by using epoxy-type structural repair agent. Literatures have proved that epoxy-type structural repair agents with benzene ring can make the high temperature performance improve slightly. Therefore, it is necessary to propose a method that can make the high temperature performance improve greatly. In this paper, a rejuvenator containing trimethylol propane triglycidyl ether (TMPTE) combined with vegetable oil (VO) was selected. At the same time, the epoxy structural repair agent containing benzene ring, i.e., E51 epoxy resin (ER) was also selected to compare these two rejuvenators on recovering the comprehensive properties of aging SMB. Through GPC, FM, AFM and TGA tests, ER repair agent has good recovery effect for SBS network structure and adhesion performance for aging SMB. While TMPTE repair agent has good recovery effect for high temperature stability of the aged SMB and molecular weight of the aged SBS. Through DSR and ductility tests, it was found that these two rejuvenators had outstanding recovery for low temperature performance of aging SMB. Through MSCR and soften point tests, it was found that the high temperature performance of the repaired SMB by TMPTE was close to non-aging SMB. This suggests that TMPTE/VO is more effective in restoring the high/low temperature performance of regenerated SMB as a whole. This study can provide guidance for the recovery of comprehensive performance of epoxy-type repair agents regenerated SMB in a cost-effective and environment friendly way.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CONTAMINANT HYDROLOGY
·
2020
·
IF 2.347
Xinran Song,Jiajun Chen,Qi Xu,Yiti Wang
To study the interactions between remediation agent injection and hydrodynamic dispersion as well as the expansion of a contamination plume, a two-dimensional sandbox experiment was conducted to simulate and monitor the mixing of a remediation agent in the contamination plume and the expansion of the contamination plume over time. Potassium permanganate is a purple solution, and it represents the remediation agent; Perchloroethylene (PCE), is dyed green and was used to observe the migration and diffusion of the contaminant and the overlap of contamination and the agent-plume. Six quantitative characterization parameters: migration distance, ( d M ), migration area, ( A M ), initial area ratio, ( K i ), spreading speed difference, ( SSD ), area ratio, ( K A ) and migration distance ratio, ( K d ), are proposed to comprehensively analyse the influence of the three factors of injection pressure, particle size and viscosity change on the mixing of a remediation agent and the expansion of the contamination plume over time. The results show that these six parameters can effectively characterize the mixing of the remediation agent and the expansion of the contamination plume, where d M , A M and K i characterize the expansion and the other three parameters characterize the mixing. The factors increasing the expansion of the contamination plume follow the order: 40 cm > 30 cm > 20 cm, for injection pressure (water head); coarse sand > medium sand > fine sand for particle size; and no polymer added > added polymer 200 mg/L > added polymer 800 mg/L > added polymer 400 mg/L for viscosity adjustment. The factors that intensify the mixing of the remediation agent in the contamination plume follow the order: 20 cm > 30 cm > 40 cm (water head); coarse sand > medium sand > fine sand; and added polymer 400 mg/L > added polymer 200 mg/L > no polymer added> added polymer 800 mg/L. Finally, conclusions from the TOPSIS method show that under optimal injection conditions, mixing is enhanced without increasing plume expansion and that the optimum injection conditions are injection pressure = 20 cm, use of a coarse sand medium, and added polymer concentration = 400 mg/L.
研究领域:
环境科学
·
水文学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Yanheng He,Sanpeng Mao,Tianwei Zhang,Shangheng Zeng,Hao Duan,Ronghua Zhuang,Jianying Yu
Styrene-butadiene-styrene triblock copolymer (SBS) modified bitumen (SMB) with excellent self-healing performance not only saves resources, but is also important for the sustainable development of pavement and construction industry. In this paper, a self-healing agent (SHA) with acylhydrazone bond was synthesized, and the dynamic acylhydrazone bond was introduced into the SBS molecular chains to prepare the self-healing SMB (SHMB). The structure of SHA was characterized, and the physical properties, chemical structure, microstructure and self-healing performance of the SHMB were investigated. Fourier transform infrared (FTIR) spectra and nuclear magnetic resonance spectra demonstrated that SHA was successfully synthesized. The physical performances of SMB were significantly improved by SHA and its optimal dosage was 0.6 %. FTIR indicated that the dynamic acylhydrazone bond was introduced into the SBS molecular chains, and formed hydrogen bonds in SHMB. The fluorescence microscope showed that SHMB had a denser network structure than SMB. The crack healing observation indicated that the crack healing speed of SHMB was much higher than that of SMB. The break tensile performance recovery showed that the recovery rate of elongation at break (R ε ) of SMB and SHMB were 14.38 % and 58.27 % after self-healing at 25℃ for 32 h, and the R ε of SMB and SHMB was elevated to 50.12 % and 92.58 % after self-healing at 40℃ for 4 h, which indicated that the introduction of dynamic acylhydrazone bonds greatly enhanced the self-healing ability of SHMB.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
·
2024
·Vol. 27
·期 24
·e202400187
·
IF 2.2
Wen Meng,Chuying Wang,Guangyong Xu,Guigen Luo,Zhengtao Deng
Graphical The Cs3Cu2Cl5 NCs synthesized with MnC2O4 as the defect repair agent exhibited negligible self-absorption, bright and stable luminesces with PL emission at about 535 nm and PLQY can be increased from 68.7 % to 100 %, which is expected to be used as highly efficient light emitter in high-efficiency X-ray scintillator. The toxicity and chemical instability shortcomings of lead halide perovskites are major concerns that continue to motivate the search for next generation alternatives. Copper halides are known to be lead-free, earth-abundant, low-cost, and environmentally friendly, and affordable in optoelectronic performance due to their bright luminescence, tunable emission wavelength, and excellent stability. However, the controlled synthesis of low-dimensional copper halide nanocrystals (NCs) with near-unity photoluminescence quantum yield (PLQY) and high stability remains a great challenge. In this work, we report a reasonable optimization approach for the preparation of Cs 3 Cu 2 Cl 5 NCs by hot-injection colloidal synthesis technology. Specifically, the Cs 3 Cu 2 Cl 5 NCs synthesized with MnC 2 O 4 as the defect repair agent exhibited negligible self-absorption, bright green luminosity with PL emission at about 535 nm and PLQY can be increased from 68.7 % to 100 %. The Cs 3 Cu 2 Cl 5 NCs shows excellent stability and outstanding optical properties, and is expected to be used as highly efficient green light emitter in high-efficiency X-ray scintillator.
研究领域:
材料科学
·
光学工程
✓ 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）