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1.
Blends of canola oil and fully-hydrogenated canola oil (FHCO) containing 10, 30, and 50 wt% FHCO were interesterified enzymatically using Lipozyme TL IM (6 % of initial substrates, w/v) under supercritical CO2 at 10 MPa and 65 °C for 2 h. Changes in polymorphic behavior and crystal morphology of non-interesterified initial blends (NIB) and purified enzymatically interesterified products (PEIP) were studied using X-ray diffraction spectroscopy (XRD) and polarized light microscopy. As well, the effects of blend ratio and enzymatic interesterification on rheological behavior were investigated. XRD analysis demonstrated the predominance of α form in FHCO while blending it with canola oil induced the formation of β form after crystallizing the samples at 24 and 5 °C for 12 h. Enzymatic interesterification caused the appearance of β′ forms and dramatically changed crystal morphology. The PEIP samples contained fewer crystal particles compared to NIB, but the crystals were more symmetrical. The elastic modulus (solid-like behavior) (G′) was lower in NIB with 30 wt% FHCO compared to the one with 50 wt% FHCO. Enzymatic interesterification also had a strong effect on G′ of the samples as it decreased after interesterification. The results of this study will help the development of conversion technologies under supercritical conditions in order to formulate more healthy fats having appropriate functional properties to address the industrial demand for the production of margarine and pastry shortenings. 相似文献
2.
Wen-Sen He Jiaxin Rui Qingzhi Wang Zhen-Yu Chen 《European Journal of Lipid Science and Technology》2021,123(7):2000398
Piceatannol has shown to be a strong antioxidant in vivo, however, its ability to suppress lipid oxidation in foods has not been examined. The present study is to examine the antioxidant effect of piceatannol on heated canola oil compared with that of butylated hydroxytoluene (BHT). The oxidation of canola oil is conducted at 60, 90, 120, and 150 °C by monitoring the depletion of oxygen, the decrease in unsaturated fatty acids, and the changes of primary and secondary oxidation products. Results demonstrated that piceatannol can suppress lipid oxidation of canola oil in a dose-dependent manner with its effect being more effective than BHT. Practical Applications: Lipid oxidation is a major factor in the deterioration of food quality. Synthetic antioxidants, such as BHT and butylated hydroxyanisole, are used to inhibit oxidation in foods, but their safety has been always concerned. Piceatannol has exhibited a strong antioxidant activity to attenuate lipid oxidation and it should be further explored for use as a natural antioxidant in foods. 相似文献
3.
Yinzhong Guo Jon H. Hardesty Vijay M. Mannari John L. MassingillJr 《Journal of the American Oil Chemists' Society》2007,84(10):929-935
Ring-opening hydrolysis of epoxidized soybean oil in the presence of phosphoric acid was studied under varying experimental
conditions. The influence of type and amount of solvents, phosphoric acid content and water content on the rate of ring-opening
reactions and the characteristics of the derived products were studied. The soy-polyols prepared were characterized by determination
of hydroxyl content, viscosity measurements, determination of average molecular weight and polydispersity index (GPC). The
structural confirmation was done by FT-IR and 1H-NMR spectroscopy. The study shows that under the reaction conditions employed, a substantial degree of oligomerization due
to oxirane-oxirane, and/or oxirane-hydroxyl reaction takes place. It is possible to synthesize soy-polyols having varying
hydroxyl content and phosphate-ester functionality by controlling the type and amount of polar solvent and phosphoric acid
content. 相似文献
4.
Carbonated soybean oil was synthesized from epoxidized soybean oil and CO2 at atmospheric pressure and with tetrabutylammonium bromide (TBABr) as catalyst. Kinetic parameters, i.e., rate constants, activation energy and pre-exponential factors were determined. The effects of catalyst concentration and water content were studied. The reaction followed first-order kinetics with respect to epoxide at 100–140 °C. A steep increase in conversion (ca. 30 %) was obtained by increasing the amount of catalyst from 3 to 5 %. Further increasing the amount of catalyst to 7 % increased the conversion less than 10 %. The reaction proceeded faster when water was added; reaction times with water were ca. 70 % of the reaction times without water. Titration, FTIR and 1H-NMR analyses indicated ca. 90 % conversion and ca. 88 % selectivity towards the carbonate after 70 h at 120 °C with 5 % mol TBABr and 1:3 molar ratio of water to epoxide. 相似文献
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6.
植物油基多元醇的合成研究 总被引:1,自引:0,他引:1
该文以环氧大豆油(ESBO)和甲醇为原料,在SO42-/ZrO2固体酸催化作用下,通过开环加成反应制备了植物油多元醇(Polyol)。借助红外、核磁共振、热分析等技术对产物结构和性质进行了分析,考察了原料配比、反应温度、反应时间和催化剂用量对ESBO转化率和多元醇合成的影响。结果表明:在反应原料配比n(甲醇)∶n(ESBO)=50∶1,反应温度373 K,反应时间2 h条件下,环氧大豆油转化率为96.8%,羟基值为198.3 mg KOH/g。 相似文献
7.
Suresh S. Narine Jin Yue Xiaohua Kong 《Journal of the American Oil Chemists' Society》2007,84(2):173-179
The feasibility of a method based on ozonolysis and hydrogenation reactions for the production of polyols from unsaturated
canola oil has been demonstrated. Polyol products with primary alcohol functional groups at position nine of each fatty acid
ester in the original triacylglycerol have been produced from canola oil. Short straight-chain alcohols were also produced
and were removed by wiped-blade molecular distillation. The pure components of the polyol, i.e. mono-ol, diol and triol were
separated by flash chromatography, and identified by Fourier-transform infrared (FTIR), 1H-nuclear magnetic resonance (NMR), 13C-NMR as well as mass spectrometry. Polyol identification was facilitated by the use of a simple high-performance liquid chromatography
(HPLC) method to determine the composition of the polyol mixture, which can be exploited as a quality-control mechanism in
designing novel polyol feedstocks. Basic correlations were established between the molecular diversity of the polyols and
their physicochemical properties, such as hydroxyl number, acidity number, and viscosity. It has been found that the produced
polyols are suitable for processing methods employing polyols for the production of polyurethanes and can be manipulated to
create polyurethanes with desirable properties. 相似文献
8.
Ring Opening of Epoxidized Soybean Oil with Compounds Containing Two Different Functional Groups
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Kemal Karadeniz Hatice Akı Mustafa Yasin Sen Yakup Çalıkoğlu 《Journal of the American Oil Chemists' Society》2015,92(5):725-731
Epoxidized vegetable oils are desirable chemicals due to their eco‐friendly characteristics and their being a major source of many green products. Ring opening is one of the ways to convert these epoxidized oils to some new intermediates. The use of mono‐functional amines, alcohols, acid anhydrides and thioethers for epoxy ring opening has been reported in the literature. In this study, thioglycolic acid (TGA) bearing thiol and carboxylic acid as two different functional groups and methyl ester of thioglycolic acid (TGAME) were used. Currently, there is no reported literature describing epoxy ring opening using chemicals bearing two different functional groups simultaneously. In this way, two new polyols were synthesized, one with TGA (polyol 1) and one with TGAME (polyol 2). FTIR and 1H‐ and 13C‐NMR spectroscopy confirmed that the ring was opened by the carboxylic acid group of TGA, and the thiol group was not involved in the ring opening whereas the ring was opened by the thiol group in the case of TGAME. 相似文献
9.
Bo Lin Liting Yang Honghai Dai Aihua Yi 《Journal of the American Oil Chemists' Society》2008,85(2):113-117
The kinetics of the oxirane cleavage of epoxidized soybean oil (ESO) by methanol (Me) without a catalyst was studied at 50,
60, 65, 70 °C. The rate of oxirane ring opening is given by k[Ep][Me]2, where [Ep] and [Me] are the concentrations of oxiranes in ESO and methanol, respectively and k is a rate constant. From the temperature dependence of the kinetics thermodynamic parameters such as enthalpy (ΔH), entropy (ΔS), free energy of activation (ΔF) and activation energy (ΔE
a) were found to be 76.08 (±1.06) kJ mol−1, −118.42 (±3.12) J mol−1 k−1, 111.39 (±2.86) kJ mol−1, and 78.56 (±1.63) kJ mol−1, respectively. The methoxylated polyols formed from the oxirane cleavage reaction , were liquid at room temperature and had
three low temperature melting peaks. The results of chemical analysis via titration for residual oxiranes in the reaction
system showed good agreement with IR spectroscopy especially the disappearance of epoxy groups at 825, 843 cm−1 and the emergence of hydroxy groups at the OH characteristic absorption peak from 3,100 to 3,800 cm−1. 相似文献
10.
Christine Bourgeois Leslie Couëdelo Muriel Subirade Maud Cansell 《European Journal of Lipid Science and Technology》2020,122(9)
The objective of this study is to formulate and characterize oil‐in‐water emulsions with plant‐derived ingredients only, that is, proteins extracted from canola oil bodies, used as co‐emulsifiers with a canola lecithin, and to assess their suitability for food applications. Using the protein extract increases the chemical stability of rapeseed oil emulsions toward oxidation, based on the delay in conjugated diene formation under accelerated storage conditions, and favors pancreatic lipase activity. Bioaccessibility of rapeseed fatty acids is compared in lymph‐duct‐cannulated rats fed oil or emulsion. Fatty acid absorption by the intestine is increased by 78% when the oil is emulsified with canola proteins as co‐emulsifier: 28.7 mg mL?1 versus 16.1 mg mL?1 for oil (p < 0.05). In vitro lipolysis results are in overall agreement with fatty acid absorption in vivo. Practical Applications: Results obtained for rapeseed oil emulsified with canola proteins and phospholipids suggest that increased bioaccessibility of n‐3 polyunsaturated fatty acids could be offered in vegan food products. 相似文献
11.
Tolibjon S. Omonov Vinay Patel Jonathan M. Curtis 《Journal of the American Oil Chemists' Society》2019,96(12):1389-1403
Epoxy thermosets comprised of plant oils along with simple curing agents are sustainable and environmentally friendly polymers. The curing agent selected, and its compatibility with epoxy monomers, strongly affects the curing kinetics, the extent of curing, and the final properties of an epoxy polymers. The goal of this work is to expand the application of epoxidized oils in formulating biobased thermoset polymer systems. Epoxidized hemp oil (EHO) was produced with 8% oxirane oxygen content (OOC) after 24 hours using in situ generated performic acid. Two model curing agents—one aromatic (trimellitic anhydride, TMA) and one biobased nonaromatic (citric acid, CA)—with similar molecular weights were selected to study the cure behavior of EHO in acetone. Both curing agents are insoluble in EHO. The prepolymerization curing reaction behavior was monitored via the OOC, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and gel permeation chromatography. It was demonstrated that at 50 °C, the reaction of EHO with TMA was extremely fast to form esters of TMA, while the reaction of EHO with CA was slower and followed different pathways. The cured EHO/TMA epoxy network is rigid and has a high alpha relaxation temperature (T α) of 89 °C, which is associated with the glass transition temperature (T g), while the cured EHO/CA network system is semirigid with a T α of 40 °C. In addition, TGA analysis showed that the EHO/TMA resin system represents a more homogenous structure compared to the EHO/CA system, as indicated by the presence of lower-temperature decompositions of citric acid derivatives. 相似文献
12.
Chemical Characterization and Physical Properties of Solvents Derived from Epoxidized Methyl Soyate
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Sean J. Riley John G. Verkade Robert J. Angelici 《Journal of the American Oil Chemists' Society》2015,92(4):589-601
Reactions of epoxidized methyl soyate (EMS) with alcohols, carbon dioxide, and acetone yielded liquids with solvent properties that make them more suitable than methyl soyate for dissolving polar substances. The reactions of EMS in the presence of Amberlyst‐15 with alcohols, including methanol, ethanol, n‐butanol, and 2‐methoxyethanol, produced a series of solvents containing ether (–OR) and alcohol (–OH) groups. Reactions of EMS with carbon dioxide and acetone gave products with carbonate and ketonide functional groups, respectively. The complex mixture of compounds present in the product, EMS(MeOH), resulting from the reaction of EMS with MeOH, was characterized by MS and NMR investigations. In addition to products resulting from MeOH addition across the epoxide ring, were major amounts of cyclic tetrahydrofuran derivatives that were derived from reactions of methyl linoleate (18:2) with MeOH. All of the solvents were characterized by high boiling points and low vapor pressures. Their viscosities were higher than that of methyl soyate. Especially notable were their very high Kauri‐butanol values, which ranged from 280 to 852, all of which are much higher than that (57) of methyl soyate. Such high KB values indicate that these solvents have very favorable solubilizing properties, which is illustrated by the ability of EMS(MeOH) to readily dissolve both polar (e.g., MeOH) and non‐polar (e.g., hexane) compounds. 相似文献
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14.
Oxirane Cleavage Kinetics of Epoxidized Soybean Oil by Water and UV‐Polymerized Resin Adhesion Properties
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Yonghui Li Donghai Wang Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2015,92(1):121-131
Di‐hydroxylated soybean oil (DSO), a biobased polyol synthesized from epoxidized soybean oil (ESO) could be used to formulate resins for adhesives; however, current DSO synthesis requires harsh reaction conditions that significantly increase both cost and waste generation. In this paper, we investigate the kinetics of oxirane cleavage in ESO to DSO by water and elucidate the role of different process parameters in the reaction rate and optimization of reaction conditions. Our kinetic study showed that ESO oxirane cleavage was a first‐order reaction and that the ESO oxirane cleavage rate was greatly influenced by tetrahydrofuran (THF)/ESO ratio, H2O/ESO ratio, catalyst content, and temperature. Optimized reaction parameters were THF/ESO of 0.5, H2O/ESO of 0.25, catalyst content of 1.5 %, and reaction time of 3 h at 25 °C. DSO with hydroxyl value of 242 mg KOH/g was obtained under these conditions. We also characterized the structure, thermal properties, adhesion performance, and viscoelasticity of UV‐polymerized resins based on this DSO. The resin tape exhibited peel adhesion strength of 3.6 N/in., which is comparable to some commercial tapes measured under similar conditions. 相似文献
15.
“一锅法”合成了2-吡啶甲醛缩邻氨基酚希夫碱钼(VI)配合物MoO2(L)(EtOH)(L= 2-吡啶甲醛缩邻氨基酚),采用红外光谱(FTIR)、热重(TG)、光电子能谱(XPS)、元素分析、电感耦合等离子体发射光谱(ICP)对配合物的结构、金属含量进行表征。研究了该配合物在合成环氧大豆油中的催化活性,考察了反应温度、时间、催化剂用量、氧化剂与大豆油摩尔比对大豆油转化率、环氧产物选择性的影响。结果表明:在80℃,2-吡啶甲醛缩邻氨基酚希夫碱钼(VI)30 mg,大豆油与叔丁基过氧化氢是1:1.5(物质的量的比),反应10 h的条件下,大豆油转化率为69.7%,环氧产物的选择性62.9%。 相似文献
16.
Wenhui Si Phil Fei Xie Ka Ying Ma Yintong Liang Xiao Bo Wang Hau Yin Chung Zhen-Yu Chen 《Journal of the American Oil Chemists' Society》2013,90(4):511-516
The present study presents the antioxidant activity of sesamin in canola oil compared with that of butylated hydroxytoluene (BHT) by monitoring the oxygen consumption and the decrease in linoleic acid and α-linolenic acid. The oxidation of canola oil was conducted at 35, 60, 90, 120 and 180 °C with addition of 50–400 ppm sesamin. Results from the oxygen consumption test showed that sesamin dose-dependently inhibited the oxidation of canola oil at concentrations of 50–200 ppm at temperatures of 60–180 °C, however, sesamin lost its antioxidant activity at a low temperature of 35 °C. The fatty acid analysis also demonstrated that sesamin at 50, 100 and 200 ppm dose-dependently prevented the oxidation of linoleic acid and α-linolenic acid in canola oil. Both the oxygen consumption and the fatty acid analysis demonstrated sesamin was less effective than BHT as an antioxidant at temperatures of 60–180 °C. It was therefore concluded that sesamin could prevent the lipid oxidation of frying fats and oil, however, its antioxidant activity was not as potent as that of BHT. 相似文献
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18.
Optimization of Soybean Oil Based Pressure-Sensitive Adhesives Using a Full Factorial Design
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Plant oils are attractive renewable feedstocks for biobased pressure‐sensitive adhesives (PSAs). In this study, we investigated how the PSA adhesion properties were influenced by the compositions comprised of epoxidized soybean oil (ESO), 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexanecarboxylate (ECHM), dihydroxyl soybean oil (DSO), rosin ester, and cationic photo initiator. When the amounts of ESO and photo‐initiator were constant, the variables of ECHM, DSO, and rosin amounts and their interactions were significant in influencing PSA peel adhesion strength, with p values smaller than 0.05 under a 95% significance level. Rosin amounts with the largest coefficient of 0.94 compared to the other variables are the most determinant factors. The peel adhesion strength was higher when using relatively a lower level of ECHM and a higher level of ESO and rosin. A model with the coefficient of determination (R2) of 95.06% was obtained to describe the relationship between the amount of resin constituents (ECHM, DSO, and rosin) and PSA peel adhesion strength in the experimental variable ranges. The optimal PSA formulation without cohesive failure was (ECHM = 0.04, DSO = 0.7, rosin = 0.7), resulting in a peel adhesion strength of 4.45 N/in. Structure–property relationships of the PSAs were established via thermal and rheological studies. 相似文献
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Nattapong Tuntiwiwattanapun Chantra Tongcumpou Darrin Haagenson Dennis Wiesenborn 《Journal of the American Oil Chemists' Society》2013,90(7):1089-1099
Aqueous surfactant-assisted extraction (ASE) has been proposed as an alternative to n-hexane for extraction of vegetable oil; however, the use of inexpensive surfactants such as sodium dodecyl sulfate (SDS) and the effect of ASE on the quality of biodiesel from the oil are not well understood. Therefore, the effects on total oil extraction efficiency of surfactant concentration, extraction time, oilseed to liquid ratio and other parameters were evaluated using ASE with ground canola and SDS in aqueous solution. The highest total oil extraction efficiency was 80 %, and was achieved using 0.02 M SDS at 20 °C, solid–liquid ratio 1:10 (g:mL), 1,000 rpm stirring speed and 45 min contact time. Applying triple extraction with three stages reduced the amount of SDS solution needed by 50 %. The ASE method was scaled up to extract 300 g of ground canola using the best combination of extraction conditions as described above. The extracted oil from the scale-up of the ASE method passed the recommendation for biodiesel feedstock quality with respect to water content, acid value and phosphorous content. Water content, kinematic viscosity, acid value and oxidative stability index of ASE biodiesel were within the ASTM D6751 biodiesel standards. 相似文献