JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2017
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IF 3.154
Weiwei Cheng,Guoqin Liu,Xinqi Liu
This research investigated the effects of Fe3+ and antioxidants on the formation of glycidyl esters (GEs) and the free radical mediated mechanisms involving the recognition of cyclic acyloxonium free radical intermediate (CAFRI) for GE formation in both the plant oil model (palm oil, camellia oil, soybean oil, and linseed oil) system and the chemical model (dipalmitin and methyl linoleate) system heated at 200 °C. Results show that Fe3+ can promote the formation of GEs, which can be inhibited by antioxidants in plant oil during high-temperature exposure. Based on the monitoring of cyclic acyloxonium and ester carbonyl group by Fourier transform infrared spectroscopy, the promotion of Fe3+ and the inhibition of antioxidants (tert-butylhydroquinone and α-tocopherol) for GE formation occurred not only through lipid oxidation but also through directly affecting the formation of cyclic acyloxonium intermediate. Additionally, a quadrupole time-of-flight tandem mass spectrometry measurement was conducted to identify the presence of radical adduct captured by 5,5-dimethylpyrroline N-oxide, which provided strong evidence for the formation of CAFRI. Thus, one possible influencing mechanism can be that free radical generated in lipid oxidation may be transferred to dipalmitin and promote CAFRI formation. Fe3+ can catalyze free radical generation while antioxidants can scavenge free radical, and therefore they also can directly affect CAFRI formation.
研究领域:
食品科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
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2024
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IF 12.7
Kang Chen,Pengrui Chen,Bei Qi,Xinyu Zhang,Lijun Cao,Ce Sun,Haiyan Tan,Yanhua Zhang
The key to achieving high-performance plant fiber/polylactic acid (PLA) composites lies in solving the interfacial compatibility issue between the two components. However, current mainstream methods for interfacial modulation often come with energy consumption and environmental concerns. To address this, our study proposed the development of fully bio-based bamboo fiber (BF)/PLA composites based on the principles of non-toxicity, low carbon footprint, and environmental friendliness. In this study, we aimed to construct a molecular-scale multiphase crosslinking network structure in BF/PLA composites. To achieve this, we utilized cyclodextrins (CD) to induce a regularized alignment of PLA molecular chains and employed epoxidized soybean oil (ESO) ring opening reaction to form bonds connecting BF, CD, and PLA molecules. This approach ensured that the composite is fully bio-based while still exhibiting remarkable mechanical properties. The resulting BF/PLA@CD-ESO composites demonstrated impressive bending strength , reaching 108.65 MPa, which was 23.11 % higher than that of the BF/PLA composites. Moreover, the tensile strength reached 67.48 MPa, which was 39.06 % higher than that of BF/PLA composites. This study provides a convenient, green and sustainable method for preparing PLA-based composites. The resulting composites are expected to be used in disposable tableware, food packaging and environmentally friendly furniture.
研究领域:
材料科学
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环境科学
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生物基材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Zifei Yan,Chencan Du,Yubin Wang,Jian Deng,Guangsheng Luo
Glycidyl esters, as a class of terminal epoxides, are important raw materials for the synthesis and modification of epoxy resins. Their synthetic routes via the dehydrochlorination of β-chlorohydrin esters are typically conducted under heterogeneous condition. Under the control of multiphase mass transfer, the inherently fast reaction can exhibit a very low observed reaction rate. Here we developed a continuous microflow system to determine the kinetic parameters of dehydrochlorination in the presence of aqueous NaOH solution. The same device was applied for the continuous production of glycidyl esters, and the conditions including flow velocity, alkali concentration, phase ratio and temperature were fully optimized. Comparing the obtained reaction performances in the microreactor with the conventional batch reactors, the required reaction time was shortened by 1/20 and the space–time yield was increased by 15 times, which is attributed to the mass transfer enhancement and the continuous operating mode. Finally, a mathematical model was established to calculate the volumetric mass transfer coefficients, whose value were in the range of 0.005–0.03 s −1 . The established microflow system and research methods could have high merit for guiding the kinetic studies and process intensification of other dehydrohalogenation reactions.
研究领域:
化学工程
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有机合成
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2025
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IF 7.3
Yuchen Zhang,Gonghao Wang,Die Yang,Yongbo Ding,Yinxiu Zuo,Liang Shen
This study developed a green and bio-based waterborne coating system that self-stratifies via silicone-induced phase separation. The system is built on a rosin acid-modified epoxy ester/acrylate hybrid resin and includes a small amount of vinyl-terminated silicone oil to promote phase separation. Two resin formulations were prepared, namely a silicone oil-free epoxy ester/acrylate hybrid resin (designated as EAR20, rosin acid constitutes 20 % of the total carboxylic acid content of epoxy ester) and a counterpart containing 2.5 wt% vinyl-terminated silicone oil (designated as EAR80–2.5, rosin acid constitutes 80 % of the total carboxylic acid content of epoxy ester). Self-stratifying coatings were fabricated by blending these two resins, with optimal performance observed at a 2:1 (EAR20:EAR80–2.5) mass ratio. During curing, the silicone-containing resin phase preferentially migrated to the surface, forming a distinct silicone-rich upper layer in a one-step process. This stratified architecture yields a hard, hydrophobic surface while preserving robust adhesion and mechanical integrity in the bulk. Compared to the silicone-free coating (with pure EAR20), the self-stratifying coating exhibited a markedly higher surface hardness (pencil hardness increased from B to H) and significantly improved durability. Water resistance in an immersion test extended from 7 days to 12 days without failure, and abrasion resistance increased from 5 ± 1 to 41 ± 2 cycles. The static water contact angle also rose from 75 ± 2° to 89 ± 2°, indicating a more hydrophobic surface. Furthermore, the silicone-rich top layer imparted anti-graffiti functionality, enabling sprayed ink to be easily wiped off without residue. Overall, this silicone oil-induced stratification strategy synergistically enhances both mechanical robustness and surface properties, offering a promising and sustainable route for developing high-performance waterborne coatings.
研究领域:
材料科学
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高分子科学
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涂料技术
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绿色化学
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表面工程
✓ 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）