POLYMER
·
2022
·
IF 4.432
Hui Wang,Chongrui Zhang,Lusha Jiang,Shan Tong,Yu-Chao Li,Hefu Pu,Qiang Zhao
Calcium bentonites (CaB), rich in European and Asian countries, are potential barrier materials for landfill leachate containment. However, CaB has to be converted into sodium bentonite (NaB) by Na-activation so as to facilitate intercalation modification. In this study, salt-resistant poly(acrylic acid-N, N-diethyl acrylamide) [P(AA-DEA)] was designed to intercalate and graft CaB by in situ polymerization without prior Na-activation. By this design, acrylic acid monomers were first adsorbed into interlayers of Ca-montmorillonite (Ca-MT) through the electrostatic complexation with Ca 2+ , dislodging Ca 2+ from montmorillonite surfaces. Then, ammonium ions of N, N-diethyl acrylamide were adsorbed into Ca-MT interlayers. Swelling index of the obtained CaB/P(AA-DEA) nanocomposite in aggressive coal combustion product (CCP) leachate is 15.8 mL/2g, which is as high as 3.4 times that of CaB. CaB/P(AA-DEA)-based geosynthetic clay liners (GCLs) exhibit very low hydraulic conductivity (1.6✕10 −12 m/s) to CCP leachate, which is as low as 3.3% that of the U.S. standard requirement and ∼4 orders of magnitude lower than that of CaB-based GCL. Polymer elution of CaB/P(AA-DEA)-8% in CCP leachate is as low as 1.9% that of the dry mixed samples.
研究领域:
环境工程
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材料科学
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土木工程
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高分子化学
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地质屏障材料
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 14
·期 1
·75-90
·
IF 1.5
Bilan Lin,Yuye Xu
To improve the corrosion resistance of fine-grain high-strength (FGHS) reinforcement, molybdate was investigated as a inhibitor. The influence of molybdate on the corrosion behavior of FGHS reinforcement in simulated concrete pore (SCP) solutions containing 1.0% or 3.5% NaCl was evaluated using polarization, electrochemical impedance spectroscopy, and Mott-Schottky curves. The corrosion products were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The results revealed that upon increasing the molybdate content, the corrosion current density ( i corr ) and donor density initially rapidly decreased and then slightly increased, while the corrosion protection efficiency and impedance first rapidly increased and then slightly decreased. The optimum molybdate was 1.0 g/L. The i corr of the former (0.058 μA cm -2 ) was considerably less than that of the latter (0.250 μA cm -2 ). The Mott-Schottky curves for the former were continuous, whereas some of those for the latter were discontinuous owing to the depletion of a less Fe 3+ in the corrosion product. Almost no pits on the reinforcement were observed for the former, whereas a few pits were still observed for the latter. Molybdate exhibited good corrosion inhibition of FGHS reinforcement at low chloride concentrations, although other or composite inhibitors should be considered for high chloride concentrations.
研究领域:
材料科学
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腐蚀工程
·
土木工程
·
电化学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Hongyuan Xing,Yangshi Liang,Gang Liu,Yao Zhang,Xing Liu,Wei Fu
The contradiction between complex compositions of bitumen and the mono organic treatment on the montmorillonite (Mt) has not been fully considered during preparing bitumen-montmorillonite nanocomposite. In this study, dual surfactants, benzyl dimethyl stearyl ammonium chloride (S1) and octadearyl dimethyl ammonium chloride (S2), were adopted to treat the Mt together to increase its compatibility with bitumen. The structure of dual organically-treated Mt was characterized and its relation to the improvement of bitumen’s properties was studied. The results indicated that S1 surfactant containing the benzene ring with a larger volume increased the interlayer space of Mt more. After mixing with bitumen, the mono and dual organically-treated Mts had almost the same basal spacing. Based on the principle of the dissolution in a similar material structure, more oil components of bitumen entered the interlayer space of Mt when it contained more S2 surfactant, and more aromatic components of bitumen did this when more S1 surfactant. The bitumen modified by mono S2 treated Mt had better PAV ageing resistance due to the protection of the oily components of bitumen from volatilization. However, the bitumen modified by dual organically-treated Mt had better resistance to the UV ageing due to the reduction of oxidation, as well as of volatilization. Therefore, it was more useful to adopt the dual organically-treated Mt to modify bitumen, and consequently to improve the durability of asphalt pavement.
研究领域:
材料科学
·
高分子科学
·
土木工程
·
沥青技术
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纳米复合材料
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 1
·57-65
·
IF 1.093
Liu Wolong,Zhang Jiupeng,Liu Qi,Pei Jianzhong,Zhu Cunzhen,Liu Peng
Micro-damages always occur and accumulate in asphalt pavement materials under the effects of temperature, vehicle loads and other factors during service. Accordingly, self-healing microcapsules could be added into asphalt binder and repair micro-damages to prevent damage extension in
time. In this study, the emulsified rejuvenator and melamine-urea-formaldehyde resin (MUF) were selected as the core and cyst wall materials, respectively, and in-situ polymerization method was applied to synthesize the novel microcapsules. The effects of emulsifier dosage and curing
time were revealed on the particle size, dispersion, surface morphology and coating properties, and the optimum process parameters were determined for microcapsules. Then, the micro morphology, molecular structure, and thermal stability were further investigated to determine the optimal preparation
of the microcapsules. Finally, the linear amplitude sweep (LAS) test was performed to evaluate the self-healing efficiency of the asphalt binder with different dosages of prepared microcapsule, and the optimal dosage of microcapsules was determined as 0.5%.
研究领域:
材料科学
·
土木工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）