JOURNAL OF MOLECULAR LIQUIDS
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2024
·
IF 5.3
Xiaogang Shang,Songwei Zhang,Huimin Yang,Songbo Li,Litian Hu
In this study, four types of ionic liquids (ILs) were synthesized and their high-temperature tribological and extreme pressure properties in pentaerythritol ester (PE) oil were systematically evaluated. Compared with commercial additive zinc dialkyl dithiophosphates (ZDDP), ILs markedly improve the load-bearing capacity and high-temperature lubrication performance of PE oil. In particular, 2-n-undecylimidazolium O,O-dioctyl dithiophosphate ([C 11 -IM][C 8 -DDP]) showed the best lubricating effect at high temperature. The tribo-film of worn surface was analyzed by SEM, EDS, XPS and FIB-TEM, and the lubrication mechanism of ILs was systematically studied. Results proved that the tribochemical reactions occurred between ILs and the worn surface, resulting in the formation of a tribo-film consisting of Fe 2 O 3 , FePO 4 , FeS, Fe x (SO 4 ) y and nitrogenous organic compounds.
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
Surfaces and Interfaces
·
2024
·
IF 5.7
Hao Xu,Run-Song Wang,Yang-Yang Yan,Xing Fan,Xiang Bai,Wen-Long Mo,Xian-Yong Wei
Twelve kinds of base oils were characterized by a series of analytical methods to obtain detailed composition and structure information. Mineral oil and poly alpha olefin oil were mainly composed of long-chain alkanes, while ester oil was mainly composed of ester compounds. Ten of the 12 base oils were selected to synthesize barium lubricating greases . Both base oils and greases were evaluated by molecular simulation , and the corresponding molecular models were constructed based on the structural information of base oils. Grease models constructed by barium 12-hydroxystearate and ester oil exhibited the largest surface adsorption energy and intermolecular interaction energy, respectively, because polar groups in lubricant tend to adsorb on metal surface and form an absorbing film. Comparing physicochemical properties of the synthesized barium lubricating greases. The temperature resistance of grease presents a positive correlation with the simulated intermolecular interaction energy.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2015
·
IF 2.912
Xianghe Meng,Lei Li,Qin Ye,Frederik van de Voort
A primary Fourier transform infrared (FTIR) method capable of determining acidity in ester-based oils is described and evaluated. Absolute free fatty acid (%FFA) and acid value (AV) calibrations were devised by spiking oleic acid into a refined, acid-free oil and measuring νCOO– at ∼1569 and νphenolate– at ∼1588 cm–1, respectively, in the second-derivative differential spectra. The FTIR acidity predictions were compared to the AOCS titrimetric method using acid mixtures as well as acid containing used vendor oils of undefined makeup and provenance, using two spectroscopically divergent reference oils as AC0. Relative to the AOCS reference method, the FTIR procedure was found to be both more accurate (±0.107 vs ±0.122) and reproducible (±0.025 vs ± 0.077) in determining %FFA and similar in predicting AV. The FTIRphenolate method overcomes a variety of limitations of earlier FTIR-based methods, being particularly simple and well suited to routine, semiautomated acidity analysis of ester-based oils using a basic FTIR spectrometer.
研究领域:
分析化学
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食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRIBOLOGY INTERNATIONAL
·
2022
·
IF 5.62
Zhixiang Li,Kunhong Hu,Yong Xu,Enzhu Hu,Xianguo Hu
A novel method was proposed to improve the dispersion and lubrication of nano-MoS 2 in ester oil. The synthesis of di-n-butyl adipate (DBA) was catalyzed at 145 °C using spherical nano-MoS 2 /sericite (S-MoS 2 /sericite), and the esterification rate reached 95.4%. After the reaction, S-MoS 2 /sericite remained in DBA with a content of ~400 mg/L, and the dispersion system could be stored stably for at least 45 days. Compared with the pure DBA, after standing for 45 days, the dispersion system reduced friction by ~16% and wear by ~72%. At high load and low speed, a tribofilm containing MoS 2 was formed at the ridge of furrow; at low load and high speed, S-MoS 2 /sericite was embedded in the soft surface to lubricate the friction pair .
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2015
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IF 1.936
Changqing Miao,Lei Zhang,Ke Zheng,Yuanchen Cui,Shengmao Zhang,Laigui Yu,Pingyu Zhang
Ploy( p -methoxyphenol), denoted as PMOP, was synthesized via an enzymatic polymerization method with p -methoxyphenol as the monomer . The corrosion resistance , tribological properties and thermal stability of as-synthesized PMOP were examined. The antioxidation behavior of as-synthesized PMOP as an antioxidant in ester oils was evaluated by rotary oxygen bomb test and pressurized differential scanning calorimetry . It was found that PMOP exhibits excellent antioxidation ability at 150 °C and 210 °C in various base oils. Besides, PMOP has much better antioxidation ability in synthetic ester oil like di-iso-octyl sebacate than several commonly used commercial hindered phenolic antioxidants.
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
TRIBOLOGY LETTERS
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2019
·Vol. 67
·期 2
·58
·
IF 2.235
Jin Yongliang,Duan Haitao,Cheng Bingxue,Wei Lei,Tu Jiesong,Liu Jianfang,Li Jian
In this study, a multi-phenol antioxidant 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenylthio)-1,3,5-triazine (THA) was synthesized. The thermal stability of THA and its oxidation resistance in triisodecyl trimellitate (TDTM) ester oil were evaluated compared with several commercial phenol antioxidants. Further investigations on the oxidation resistance and tribological performance of THA with dinonyl diphenylamine (Am) and ZDDP composites were conducted to determine the additive compatibility in TDTM. The results indicate that the THA possesses higher thermal stability and more effectiveness of oxidation resistance than the commercial phenol antioxidants. The synergistic anti-oxidative effect is confirmed for the THA/Am mixtures in TDTM ester oil. However, the addition of THA alone or THA/Am mixtures shows no improvement for the tribological performance of TDTM. Excitingly, the THA/Am/ZDDP composite additives not only have the superior oxidation resistance, but exhibit the effective friction and wear reductions. It suggests the excellent compatibility of the synthesized THA antioxidant with Am and ZDDP additives in TDTM ester oil.
研究领域:
材料化学
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润滑材料
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应用化学
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高分子化学
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表面科学
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机械工程
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石油化学
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摩擦学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）