IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
·
2024
·
IF 2.9
Shuang Hu,Zhuang Fu,Jiawen Zhang,Yihua Qian,Hongmei Wang
The combination of phenolic and amine additives represents a traditional approach for the co-formulation of antioxidant compounds in insulating oils. However, the introduction of amines not only induces significant alterations in the inherent characteristics of the oil but also gives rise to aging by-products that are environmentally detrimental. This study examines the aging behavior of three commonly employed phenolic antioxidants, namely BHT, BHA, and TBHQ, when added individually or in combination to synthetic ester insulating oil. The investigation reveals that the co-formulation of phenolic antioxidants demonstrates exceptional antioxidant efficacy within synthetic ester insulating oil. Through the oxidative stability test, it is observed that incorporating a combination of 0.3 wt% BHT and 0.1 wt% BHA into the oil maintains the dielectric dissipation factor at 0.681%, representing a mere 0.202% increase compared to fresh oil. Furthermore, the total acid number can be sustained at 0.01 mg KOH/g, and the breakdown voltage can be up to 78 kV. This study employs linear sweep voltammetry (LSV) and Fourier-transform infrared spectroscopy (FT-IR) to analyze the behavior of antioxidants and the degradation products of aged oil samples. A preliminary investigation into the synergistic antioxidant mechanism of phenolic antioxidants in synthetic ester insulating oil is conducted, to provide a novel approach for the formulation of antioxidant compounds.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2016
·
IF 2.857
Qin Li,Xiaobo Huang,Shaochen Li,Jingchun Ma,Min Lv,Hui Xu
A total of 20 esters of fraxinellone C4/10-oxime were synthesized and determined by melting points, optical rotation, infrared spectra, proton nuclear magnetic resonance spectra, and high-resolution mass spectrometry spectra. Two steric configurations of compounds 7i and 8i were unambiguously confirmed by X-ray crystallography. Additionally, their pesticidal activities were assessed on two typical lepidopteran pests, Mythimna separata Walker and Plutella xylostella Linnaeus. Generally, all compounds exhibited less potent oral toxicity than toosendanin against third-instar larvae of P. xylostella. However, all compounds showed the growth inhibitory property against early third-instar larvae of M. separata. Notably, compounds 7m, 8b, 8k, 9, and 11 displayed more potent pesticidal activity than toosendanin. This demonstrated that introducing the C-4 carbonyl or oxime group on fraxinellone resulted in more promising derivatives than those bearing a C-10 carbonyl or oxime substituent.
研究领域:
植物化学
·
农药科学
·
有机化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
·
2024
·
IF 2.9
Ying Zhang,Feipeng Wang,Shi Li,Sichen Yan,Bojun Li,Zhengyong Huang,Jian Li
Synthetic ester insulating oil emerges as an environmentally friendly substitute for mineral insulating oil. However, the intrinsic ester structure poses challenges to its oxidation stability, making improvement necessary. This paper compares the impact of three phenolic antioxidants, specifically 2,6-di-tert-butyl-4-methylphenol (T501), tert-butylhydroquinone (TBHQ), and 4,4’-methylenebis (2,6-di-tert-butylphenol) (T511), on improving the thermal oxidation stability of pentaerythritol ester insulating oil (KKA). The antioxidants are introduced at molar ratios of 6 μmol/g and 18 μmol/g. The thermal oxygen aging tests indicate that all three antioxidants mitigate the deterioration of KKA’s physicochemical and electrical properties to varying extents. TBHQ exhibits the most pronounced effectonenhancing KKA’s thermal stability, as evidenced by he highest extrapolated onset temperature obtained via thermogravimetric analysis and differential scanning calorimetry (TG-DSC) in a nitrogen atmosphere. T511 is the most influential in improving KKA’s oxidation stability, characterized by its superior onset oxidation temperature and highest capacity to elevate the initial oxidative activation energy of KKA determined through non-isothermal DSC. Furthermore, the lowest bond dissociation energy ofT511 indicates a most facilitated release of hydrogen atoms, providing additional evidence for its superior antioxidant efficiency.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Zongpeng Liu,Shaojian Hu,Yuning Zhang,Bencheng Wu,Jianhua Zhu
Synthetic esters are expected to have broad application prospects in the high-end lubrication sectors owing to their fascinating custom-tailored properties. Herein, we synthesized a novel complex polyolester (CPE) via a stepwise esterification procedure using stannous oxide as a heterogeneous catalyst. Response surface methodology coupled with the Box–Behnken design (BBD-RSM) was employed to optimize the experimental parameters and elucidate the interactions among the operating variables on the low-temperature fluidity of CPE. The optimization results indicated that the lowest pour point (−42 °C) could be obtained under the catalyst dosage of 1.2 wt%, the first step reaction temperature of 164 °C, the first step reaction time of 100 min, and the second step reaction temperature of 178 °C. Particularly, there is a significant interactive effect between the catalyst dosage and the second step reaction temperature. Followed by the molecular distillation of the crude ester prepared under the optimal conditions, the refining results revealed that the non-ideal components had been effectively removed and the total acid number of the final product was substantially reduced to below 0.1 mg KOH/g. The molecular structures of the as-synthesized esters were confirmed by FT-IR, NMR, GPC, ESI–MS, and TGA characterization and their physicochemical and tribological properties were also evaluated according to standard methods. In view of the unique molecular structural design, the developed CPE displayed plentiful prominent technological specificities, which makes it plausible to be served as a potential high-performance base stock. Therefore, the findings of this study may provide some valuable insights for expanding the application scope of synthetic esters into various special industrial scenarios.
研究领域:
化学工程
·
材料科学
·
润滑技术
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL LUBRICATION AND TRIBOLOGY
·
2025
·
IF 1.8
Lin Ma,Chenghong Hu,Zhenlin Lv,Xi He,Rui Dong,Mingjin Fan
Purpose This study aims to develop synthetic ester lubricating oil using renewable sinapic acid as raw material, to explore the structural design and selection of raw materials for green, high-performance synthetic ester oils. Design/methodology/approach A series of the sinapate ester oils were synthesized through esterification and alkoxylation reactions using renewable source sinapic acid as the raw material. The molecular structures of the oils were characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy spectroscopy and elemental analysis. The oils were evaluated for safety, viscosity-temperature properties, thermal and oxidative stability, as well as friction reducing and anti-wear characteristics. Findings Compared to commercial base oil tris (2-ethylhexyl) trimellitate (Phe-3Ci8), the bio-lubricant exhibits superior antifriction and anti-wear properties. Notably, the JCi8-C12 sample performed exceptionally well, reducing the friction coefficient by 11.42% and wear volume (WV) by 54.44% in steel/steel tribo-pairs. In steel/aluminum tribo-pairs, the friction coefficient decreased by 27.48%, while WV was reduced by 85.81%. Mechanistic studies reveal that the introduction of short-chain methoxy groups and stable conjugated systems (aromatic rings and double bonds) inhibit oxidation and decomposition at elevated temperatures. The p-p stacking effect enables lubricant molecules to arrange stably on friction surfaces, forming a durable lubricating film. Originality/value The utilization of biomass resources to develop green synthetic lubricating oil with excellent performance not only enhances the added value of waste from agricultural processing but also offers significant benefits in terms of both economic and environmental sustainability.
研究领域:
材料科学
·
化学工程
·
可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
Lubrication Science
·
2022
·Vol. 34
·期 5
·347-355
·
IF 1.307
Yongliang Jin,Jian Li,Weimin Lee,Bingxue Cheng,Dan Jia,Jiesong Tu,Shengpeng Zhan,Tian Yang,Haitao Duan
This study aims to investigate a novel high-efficient antioxidant for synthetic ester oils. An ester-bridged antioxidant, phloroglucinol tris (3-[3,5-di-tert-butyl-4-hydroxyphenyl]) propionate (PTP), was successfully synthesised in high yield under relatively mild reaction conditions. Thermal stability and oxidation resistance of diisooctyl adipate (DOA) ester oil were determined and compared to the typical commercial phenol antioxidants, including its tribological properties. The results indicate that the prepared PTP antioxidant exhibits considerably higher thermal stability than commercial antioxidants, and it also improves the oxidation resistance of the synthetic ester oil more effectively. Moreover, the addition of PTP antioxidant enhanced the wear protection of DOA ester oil without deteriorating its lubricating performance. The ester-bridged antioxidant can be used as a multifunctional additive, which not only exerts excellent thermal stability and oxidation resistance, but can also act as an efficient anti-wear agent in synthetic ester oils.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
WEAR
·
2025
·
IF 6.1
Zhengquan Jiang,Jiahao Wu,Chuanwei Qiao,Laigui Yu,Jinglei Bi,Yadong Wang,Zhongzheng Yang,Shengmao Zhang,Yujuan Zhang,Weihua Li
Synthetic ester oils are crucial for high-precision equipment lubrication. Strongly polar ester oils competitively adsorb with conventional additives, hindering their effectiveness. This paper proposes the use of FeCoNi nanoparticles as the additive for diisooctyl sebacate (DIOS), a polar synthetic ester oil, attempting to overcome the issue of competitive adsorption faced by traditional additives in polar base oils. Specifically, oleylamine-modified FeCoNi (OA-FeCoNi) nanoparticles were prepared as the additive for DIOS base oil by in situ surface modification technique combined with polyol method, a one-pot liquid-phase chemical method. Friction and wear tests as well as adsorption experiments confirmed the strong adsorption capability of OA-FeCoNi nanoparticles on steel surfaces, demonstrating their effectiveness in enhancing lubrication performance. The present approach, hopefully, would shed light on the facile and well available design and fabrication of efficient anti-wear and friction-reducing agents for polar synthetic ester oils.
研究领域:
材料科学
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Shuang Hu,Zhuang Fu,Jiawen Zhang,Yihua Qian,Hongmei Wang
Synthetic ester insulating oils have a high kinematic viscosity and dielectric dissipation factor, making it less likely that heat will be transferred during actual operation. The two-dimensional material hexagonal boron nitride (h-BN) has excellent insulating and heat dissipating properties, which can be added to the insulating oil to improve the electrical properties of the insulating oil. In this study, the isolated hexagonal boron nitride was first characterized morphologically and structurally using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-visible spectroscopy. Subsequently, the hexagonal boron nitride was added to the pentaerythritol ester oil. Its dispersion stability was first analyzed by determining its size distribution and zeta potential magnitude using dynamic light scattering. Then, the effects of different sizes of hexagonal boron nitride on the dielectric properties and breakdown voltage of the ester oil were evaluated. The results showed that h-BN with a size diameter of 2 μm was more effective in reducing the dielectric dissipation factor to 25% and increasing the volume resistivity by 155% when added at a concentration of 0.01 wt% compared to the base oil. In contrast, h-BN with a size diameter of 0.6 μm at 0.005 wt% significantly increased the average AC breakdown voltage from 66.7 kV in the untreated oil to 79.4 kV. For further insights, dipole moment and electrostatic potential analyses were employed, which showed that h-BN particle size and surface bonding affected the electrical properties of the ester solution.
研究领域:
材料科学
·
电气工程
·
纳米技术
·
应用物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Muhammad Fasehullah,Feipeng Wang,Sidra Jamil
Synthetic ester (SE) oil-based nanofluids (NFs) are indispensable for high voltage (HV) applications due to their impressive properties; for instance, high biodegradability, environmental friendliness, high dielectric strength and thermal stability. In this work, the solvothermal route is adopted to synthesise cadmium sulfide (CdS) nanomaterials of three different morphologies. CdS nanoparticles (NPs) possess a zinc blende (cubic) phase; however, CdS nanobelts (NBs) and CdS ultra-thin nanosheets (NSs) exhibit a wurtzite (hexagonal) phase. Thereafter, CdS nano-additives are dispersed in SE oil (MIDEL-7131) to investigate the influence of phase, morphology and bandgap of nano-additives on the AC breakdown characteristics of nanofluids. The resultant NFs exhibit significantly augmented AC breakdown strength because of expedited charge scavenging ability due to high bandgap and the formation of an electrical double layer (EDL). NPs based nanofluid (SE/NPs), NBs based nanofluid (SE/NBs), and NSs based nanofluid (SE/NSs) display their optimum doping concentration of 0.3 g/L, 0.3 g/L, and 0.2 g/L, respectively. Furthermore, the thermal stability of NFs of optimum doping concentration is investigated and compared with SE via TGA/DSC/DTG technique. The findings evince that the initial decomposition temperature is high and heat dissipation is low in NFs compared to SE, which indicates that the nanofluids are thermally stable both in air and nitrogen. Finally, the kinematic viscosity measurements of NFs of optimum doping concentration exhibit slightly lower viscosity than that of SE. Hence, CdS nano-additive is proved to be a magnificent potential aspirant which is highly efficient for insulating oil-based NFs development without any surfactant.
研究领域:
电气工程
·
材料科学
·
纳米技术
·
高压工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）