Journal of Cleaner Production
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2019
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IF 6.395
Hongran Zhao,Jianxiang Feng,Jin Zhu,Haibin Yu,Yuejun Liu,Pu Shi,Shengpei Wang,Shenggao Liu
3 The greatest challenge of vegetable oils (VOs) used as green lubricants is their oxidation stability. The potential of incorporating sustainable components to VOs as high efficient antioxidant additives can be beneficial to both energy conservation and environment protection. In this paper, bio-based multifunctional additives (BMAs) were specially designed and synthesized with the aim of maximizing VOs’ oxidation stability by combining biophenols (gallic acid, caffeic acid and p-hydroxycinnamic acid) with 4-aminodiphenylamine in one molecular. The BMAs were found to have extraordinary higher thermal stability and free radical scavenging activity than that of commercial antioxidants. BMAs were evaluated as multifunctional additives in VOs. Pressure differential scanning calorimetry (PDSC) indicated that the oxidation induction time (OIT) of rapeseed oil (RO), coconut oil (CO) and epoxy soybean oil (ESO) can be increased correspondingly by about 2.2, 14.0 and 32.0 times with the addition of BMAs. Four ball test showed that bio-based multifunctional additives 3 (BMA3) had the best antiwear activities among three BMAs (18% decrease in RO), better than traditional zinc dialkyl dithiophosphate (ZDDP) in CO and ESO. In a comparison to commercial phenol, arylamine antioxidants and their physical mixtures, BMAs demonstrated superior antioxidant properties with the increase of phenol hydroxyl group, which mostly benefit from the polyphenolic and aryl amine intramolecular synergism.
研究领域:
化学工程
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环境科学
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材料科学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2017
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IF 5.951
Jianxiang Feng,Hongran Zhao,Sen Yue,Shenggao Liu
The use of biophenols to develop bioantioxidants is devoted to sustainable development, reducing energy and environmental issues. In order to step closer to practical application, bioantioxidant effectiveness is as important as renewability. A novel intramolecular synergism strategy aiming at high-efficiency oxidative inhibition is proposed by combining biobased phenol and arylamine in one molecule. Mannich condensation of hydrogenated cardanol (HC) with arylamines and paraformaldehyde led to the formation of three phenol-arylamine antioxidants (BAs). BAs were characterized by HRMS, FT-IR, NMR, and thermogravimetic (TG) analysis. Free radical scavenging activity of BAs was assessed using a DPPH (1,1-diphenyl-2-picrylhydrazyl) method, and was found to be much higher than that of commercial antioxidants. BAs were evaluated as antioxidant and thermal-oxidative stabilizer in polyol in terms of pressure differential scanning calorimetry (PDSC), rotary bomb oxidation tests (RBOT), and TGA. In a comparison to commercial antioxidants, BA1 demonstrated superior antioxidant properties and thermal-oxidation stability, which mostly benefit from intramolecular synergism.
研究领域:
化学工程
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材料科学
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可持续发展
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DOI
高影响因子
Polymers
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2019
·Vol. 11
·期 9
·1389
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IF 3.164
Jianye Ji,Xin Ge,Weijie Liang,Ruiyuan Liang,Xiaoyan Pang,Ruoling Liu,Shuyi Wen,Jiaqi Sun,Xunjun Chen,Jianfang Ge
MQ silicone resins represent a broad range of hydrolytic condensation products of monofunctional silane (M units) and tetrafunctional silane (Q units). In this work, a Bio-Phenol MQ silicone resin (BPMQ) was designed and synthesized by the hydrosilylation of hydrogen containing MQ silicone resin and eugenol in the presence of chloroplatinic acid. The structure, thermal property, and antibacterial property againstEscherichia coliof the modified MQ silicone resin were investigated. The results showed that BPMQ has been prepared successfully, and the thermal stability of this modified polymer improved significantly because of the introduction of phenyl in eugenol. The temperature at the maximum degradation rate increased from 250 °C to 422.5 °C, and the residual yields mass left at 600 °C were increased from 2.0% to 28.3%. In addition, its antibacterial property againstEscherichia coliwas also enhanced markedly without adding any other antimicrobial agents. This improved performance is ascribed to special functional groups in the structure of eugenol. The BPMQ polymer is expected to be applied to pressure-sensitive adhesives and silicone rubber products for the biomedical field due to its reinforcing effect and antioxidant quality.Keywords:Bio-Phenol MQ silicone resin;hydrosilylation;modified;thermal stability;antibacterial property
研究领域:
材料科学
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生物医学工程
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DOI
PubMed
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2021
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IF 6.186
Yunwu Zheng,Jida Wang,Donghua Li,Can Liu,Yi Lu,Xu Lin,Zhifeng Zheng
To improve the quality of bio-oil and minimize coke formation, ex-situ catalytic biomass pyrolysis vapor upgrading to high-grade bio-aromatic and phenol compounds with Py-GC × GC/MS at different nickel-to-copper ratios was investigated. At the same time, the deoxygenation efficiency, structure-activity relationship, deactivation mechanism and possible pathways between combined mono- and bimetallic catalysts were also demonstrated. Ni and Cu species could be well dispersed, and the HZSM-5 support maintained the MFI crystal structure after bimetallic Ni–Cu modification, but the surface area, pore volume, and total acidity decreased. Bimetallic Ni–Cu catalysts showed better deoxygenation efficiency than monometallic catalysts, which had more advantages in the preparation of aliphatic hydrocarbons (29.86%) than mono- and bimetallic catalysts, which favored the production of aromatics (28.89%). Higher-Ni-loading catalysts promoted the formation of aliphatic hydrocarbons, aromatics and alkanes due to decarboxylation, decarbonylation and aromatization reactions, and higher-Cu-loading catalysts enhanced the olefin and phenol yields due to dehydration and demethylation reactions. Overall, the highest yields of bio-aromatic compounds and phenols were46.78% and 36.34%, respectively, at Ni-to-Cu ratios of 1:1 and 1:2, due to the high total acid amount and suitable average pore size for bio-aromatics and the low acidity and large pore size for phenols. The bimetallic Ni–Cu catalyst significantly increased the quality of bio-oil and reduced coke deposition.
研究领域:
催化化学
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能源化学
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材料科学
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DOI
高影响因子
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