Fats from Chemically Interesterified High-Oleic Sunflower Oil and Fully Hydrogenated Palm Oil

Chemical interesterification of different lipid materials has considerable potential for the production of a wide variety of special fats with improved functional and nutritional properties. The present study aimed to evaluate the chemical interesterification of blends of high-oleic sunflower oil (HOSO) and fully hydrogenated palm oil (FHPO) in the ratios (% w/w) of 80:20, 70:30, 60:40 and 50:50. The blends were characterized in triacylglycerol composition, melting point, solid fat content and crystallization behavior, and some applications in food products were suggested. The interesterification altered the solid fat content, melting point and crystallization isotherm of the samples, after the levels of trisaturated triacylglycerols decreased and disaturated–monounsaturated and monosaturated–diunsaturated triacylglycerol contents increased, due to the randomization of fatty acids. The modification in the triacylglycerol composition promoted greater miscibility between the HOSO and FHPO fractions, creating new application possibilities for the food industry.     

Dry Fractionation and Crystallization Kinetics of High-Oleic High-Stearic Sunflower Oil

Fractionation of fats and oils makes it possible to generate products with specific properties from natural fats that contain a variety of triacylglycerol (TAG) species. High-oleic high-stearic (HOHS) sunflower oils contain high levels of saturated fatty acids, mainly stearate, on a high-oleic background. Accordingly, HOHS oils could be a source of disaturated TAGs appropriate for cocoa butter equivalent formulations. We examined the kinetics of HOHS oil crystallization, paying special attention to the influence of crystal seeding and temperature on the process and the composition of the final fractions. This oil was fractionated at 18 °C, and seeding increased the amount of disaturated TAGs recovered in the precipitate from 23% to up to 30%. The experimental data collected were fitted using the models of Gompertz and Avrami to study how well these models fitted the data and their utility in predicting the progress of crystallization. At seeding additions above 0.25% there was a change in the crystallization mechanism that improved the process of fractionation. The effect of temperature was also studied, showing important increases in the maximum rates of crystallization when fractionations were carried out at lower temperatures. Finally, the melting profiles of the fractions enriched in saturated fatty acids were studied, showing amounts of solids intermediate between the initial oil and cocoa butter.     

Crystallization Behavior of High-Oleic High-Stearic Sunflower Oil Stearins Under Dynamic and Static Conditions

Soft (SS) and hard (HS) stearins obtained from high-oleic high-stearic sunflower oil were isothermally crystallized under dynamic (with agitation) and static conditions at 16, 17, 18, 19, and 20 °C and 24, 25, 26, 27, and 28 °C, respectively. Both fractions crystallized under the α-form at early stages of crystallization for all temperatures (T _c) tested. Polymorphic behavior strongly changed with T _c and shear conditions for both fractions. SS fractions were characterized by α, β₂ and/or β₁ polymorphs at lower T _c and β₁ crystals at higher T _c when crystallized under dynamic conditions, while this same fat system was characterized by β₂′ crystals at lower T _c and β₂ at higher T _c under static conditions. HS samples were mainly characterized by α and β₂ crystals at lower T _c and α and β₁ crystals at higher T _c when crystallized under dynamic conditions; while the same fat was characterized by β₁′ crystals when crystallized at lower T _c and α when crystallized at higher T _c under static conditions after 90 min at T _c. These different polymorphic behaviors, in combination with the different processing and tempering temperatures are translated in specific textural behavior of the samples.     

Germicidal Properties of Ozonated Sunflower Oil

The aim of this work was to establish the minimal inhibition concentration (MIC) of ozonated sunflower oil for various microorganisms. To determine the influence of the ozonated medium on the growth of bacteria Bacillus subtilis, Escherichia coli and yeast Candida albicans the Petri dish method was used. Chemical and physical properties of ozonated sunflower oil were additionally studied. Microbiological studies proved that these microbes have various sensibility against ozonated oil. The most resistant are gram-negative bacteria E. coli and the yeast C. albicans. Gram-positive bacteria, B. subtilis turned out to be less resistant, because no growth was observed for preparation with an ozone dose of 200 mgO₃/g oil.     

PEG、PPG改性PLA材料的性能研究

采用熔融共混法用聚乙二醇(PEG)对生物可降解材料聚乳酸(PLA)进行改性,研究了PEG的相对分子质量对共混体系热性能和力学性能的影响,对比了相同相对分子质量的PEG和聚丙二醇(PPG)由分子结构差异对共混体系性能的影响。结果表明,PEG的相对分子质量为2 000时,改性效果最好;相同相对分子质量的PEG改性效果优于PPG。     

石蜡油、环烷油填充SEBS/PBT共混物性能对比

选取石蜡油KP6030以及环烷油KN4010作为两种填充油,分别制备了聚苯乙烯-乙烯-丁二烯-苯乙烯(SEBS)/聚对苯二甲酸丁二酯(PBT)共混物。研究了不同填充油以及不同的PBT含量对共混物的力学性能、流动性能的影响。同时使用扫描电子显微镜(SEM)对部分SEBS/PBT共混物的断面形貌进行了分析研究。结果表明:两种填充油对共混物性能的影响效果基本相似,以石蜡油为填充油的SEBS/PBT共混物力学性能更优,但流动性能较差。随着PBT含量的增加,共混物的相容性呈现由差到好的趋势,导致共混物的熔体流动速率(MFR)先下降后上升。同时力学性能测试结果表明,随着PBT含量的提高,两组共混物的拉伸强度以及硬度均出现了显著的提升,拉伸强度分别由2.75 MPa及2.46 MPa提升至4.93 MPa及5.57 MPa,硬度分别由42.5及45.8提高至67.2及72。力学性能得到有效的改善,但PBT含量的提高抑制了共混物的流动性能,MFR呈现一定程度的下降,石蜡油组共混物的MFR由18.5 g/10min下降至16.6 g/10min,环烷油组共混物的MFR由27.4 g/10min下降至24.5 g/10min。     

桐油成膜材料的生物降解性研究

以土壤和活性污泥中的微生物来降解桐油缓(控)释肥料的成膜材料,通过测定试样在降解过程中的CO2释放量、质量损失百分率和表面形貌来综合评价成膜材料的生物降解性能。结果表明,用桐油作为成膜材料制备缓(控)释肥料,养分释放后残留在土壤中的包膜肥料壳囊可以被生物降解,对环境友好。     

The Effect of Epoxidized Sunflower Oil on the Miscibility of Plasticized PVC/NBR Blends

Blends of plasticized poly(vinyl chloride) (PVC) with several ratios of nitrile rubber (NBR) were studied. The effects of epoxidized sunflower oil (ESO) in combination with di-(2-ethylhexyl)phthalate (DEHP) in the PVC blends on the tensile strength, elongation, hardness, and dynamical mechanical analysis (DMA) were studied. The modulus and hardness results revealed that the addition of ESO to the blend favors the miscibility of PVC and NBR. The PVC/NBR/(DEHP-ESO) blends behave as a compatible system as is evident from the single T _g observed in DMA. The moderate level broadening of the T _g zone in blends is due to the presence of ESO in the plasticizer system. Blends of plasticized PVC and nitrile rubber showed promising properties. The ESO is suitable to partially replace DEHP in PVC/NBR blends.     

Research of the Thermal and Strength Properties for Materials Obtained with Sunflower Oil

The use of pulverized fly ash (PFA) obtained from thermal power plants and epoxidized sunflower oil (ESFO) as recycled material in the construction industry was investigated. Epoxidized sunflower oil, clay (C) and pulverized fly ash were mixed at various proportions and were fired at 160, 180 and 200°C. The thermal conductivity and strength (compressive strength, tensile strength and abrasion loss) of the samples were determinated. The lowest value of thermal conductivity, 0.25 W/mK, was measured for the sample with a 70% FA/30% C ratio and 50% ESFO processed at 200°C. This sample had the lowest compressivetensile strength (3.28 MPa–0.633 MPa) and the highest abrasion loss (4.39%). The highest compressivetensile strengths and the lowest value of abrasion loss observed, were 7.21 MPa–0.939 MPa and 1.15%, respectively.     

聚乙二醇改性菜籽油的碱催化合成及性能

在固体碱催化下,由菜籽油改性制得的菜籽油脂肪酸甲酯与聚乙二醇400(PEG400)进行酯交换反应,合成了绿色可降解的多功能非离子表面活性剂聚乙二醇脂肪酸酯。对酯交换反应的主要影响因素和产物性能进行了考察。结果表明,在m(菜籽油脂肪酸甲酯)∶m(PEG400)=2.0∶1.0,催化剂w(CaO/ZrO2)=0.8%(相对于反应物总质量),温度130℃,反应时间7.5h的条件下,聚乙二醇脂肪酸酯产率达91.56%;产物浊点53℃、表面张力35mN/m、乳化性361s、润湿力59s,说明具有很好的表面活性。     

耐油性PA6/NBR共混物的制备与性能研究

采用不同种类的丁腈橡胶(NBR)与聚酰胺6(PA6)熔融共混制备了聚酰胺6/丁腈橡胶混合物(PA6/NBR),考察了共混过程中转矩值的变化,并研究了不同腈基含量共混物的拉伸性能及耐溶剂性能。结果表明,随着橡胶相含量的增加,共混物的熔体黏度、体积溶胀率与质量溶胀率均显著提高,但拉伸强度下降。红外光谱分析表面NBR与PA6在高温高剪切作用下存在微化学反应,并且随腈基含量的增加,PA6/NBR共混物的平衡转矩值增大,拉伸强度明显提高,耐溶剂性下降。     

Structure and Physical Properties of Organogels Developed by Sitosterol and Lecithin with Sunflower Oil

High linoleic acid sunflower oil (HLSO) with various sitosterol (Sit) to lecithin (Lec) mass ratios (i.e., 0:100–100:0) were used to develop organogels at two storage temperatures (T_s: 5 and 25 °C). The results showed that, at 25 °C, the hardness value of organogels obtained from HLSO with both Sit and Lec was higher than that of organogels developed from HLSO with only Sit or Lec. Microscopy revealed that the shapes of the crystals in the organogels varied significantly with the composition of the structurant and the T_s. At both T_s used, the Sit:Lec (80:20) system had a lower degree of supersaturation compared with the (100:0) system. X‐ray diffraction (XRD) revealed that Sit:Lec mass ratio of 70:30, 80:20 and 100:0 had similar short spacings, and the presence of Lec might be adverse to the formation of Sit crystal in oil. Small‐angel X‐ray scattering (SAXS) showed that the layer thickness of Sit/Lec/HLSO organogel was larger than that of Sit/HLSO organogel. It was found that the presence of Lec induced the change of self‐assembly structure of Sit in HLSO and caused the changes of physical properties of organogels obtained.     

Rheological and Film-Forming Properties of Chitosan Composites

Chitosan (Chit) and its composite films are widely used in biomedical, cosmetic, and packaging applications. In addition, their properties can be improved and modified using various techniques. In this study, the effect of the type of clay in Chit composites on the structure, morphology, and physical properties of Chit solution and films was tested. The liquid flow properties of Chit solution with and without clay were carried out using the steady shear test. Chit films containing clay were obtained using the solution-casting method. The morphology, structure, and physical properties of the films were characterized by scanning electron microscopy, atomic force microscopy, infrared spectroscopy, swelling behavior, and tensile tests. The results reveal that for the Chit solution with clay (C1) containing 35 wt.% dimethyl dialkyl (C14–C18) amine, the apparent viscosity is the highest, whereas Chit solutions with other clays show reduced apparent viscosity. Rheological parameters of Chit composites were determined by the power law and Cross models, indicating shear-thinning behavior. Analytical data were compared, and show that the addition of clay is favorable to the formation of intermolecular interactions between Chit and clay, which improves in the properties of the studied composites.     

不同成膜物质配比和成膜助剂用量对漆膜性能的影响

寻找水性木器漆中聚氨酯分散体与丙烯酸乳液的最佳配比及其成膜助剂最合理用量,使漆膜的性能得到充分发挥。水性聚氨酯分散体与水性丙烯酸乳液配比为1∶3(质量比),成膜助剂用量为6.0%～6.5%(质量分数)时,水性木器漆漆膜硬度、抗粘连性、耐水性和耐醇性最理想。     

Physicochemical Properties of Interesterified Blends of Fully Hydrogenated Crambe abyssinica Oil and Soybean Oil

The chemical interesterification of blends of soybean (SO) and fully hydrogenated crambe oil (FHCO) in the ratios of 80:20, 75:25, 70:30, 65:35, and 60:40 (w/w), respectively, was investigated. FHCO is a source of behenic acid. The blends and the interesterified fats were analyzed for fatty acid and triacylglycerol composition, regiospecific distribution, slip melting point, solid profile, and consistency. The regiospecific analysis of the TAG indicated random insertion of saturated fatty acids at sn-2 of the glycerol of the interesterified blends with more significant alterations at sn-2 than at sn-1 and sn-3. The gradual addition of FHCO increased the solid fat content and the slip melting point. The chemical interesterification formed new TAG facilitating the miscibility between SO and FHCO. The 70:30 interesterified blend was suitable for general use, 60:40 for use as a base stock. At 35 °C, the 65:35 interesterified blend showed suitable plasticity for use in products with fat contents below 80 %. FHCO, rich in behenic acid, is not associated with increased total cholesterol and LDL cholesterol, and it can be used as a low trans fat. FHCO is not associated with increased total cholesterol and LDL cholesterol, and it can be used as a low trans fat alternative.     

环氧葵花油的合成及其对PVC性能的影响

采用无溶剂工艺合成了环氧葵花油,并利用转矩流变仪、差示扫描量热仪等进一步研究了其对聚氯乙烯（PVC）热稳定性、增塑效果的影响。结果表明,反应温度为60 ℃、反应时间为5 h、过氧化氢和葵花油摩尔比为2:1、催化剂用量为原料总质量的3 %时,环氧葵花油的环氧值达到了6.78 %;环氧葵花油与钙锌稳定剂并用具有协同作用,可以增强PVC的长期热稳定性,效果比环氧大豆油更好;环氧葵花油还能使PVC的玻璃化转变温度、硬度、拉伸强度降低,断裂伸长率升高,可以作为PVC增塑剂使用。     

葵花油琥珀酸淀粉酯的制备及其性质研究

淀粉烯基琥珀酸酯是烯基琥珀酸酐和淀粉在碱性条件下反应的产物,主要用于乳化和增稠,同时可用作微胶囊壁材[1].酯化后的淀粉物理化学特性发生了很大变化[2],可广泛应用于纺织、食品、造纸、医药等多个领域[3].     

Quantitation of Hydroperoxy-, Keto- and Hydroxy-Dienes During Oxidation of FAMEs from High-Linoleic and High-Oleic Sunflower Oils

The objective of this work was to study the quantitative formation of hydroperoxydienes, ketodienes and hydroxydienes during autoxidation at 40 °C of fatty acid methyl esters derived from two sunflower oils with different degree of unsaturation, high-linoleic sunflower oil and high-oleic sunflower oil. The analysis of the oxidation compounds was carried out by NP-HPLC–UV and results were compared to the specific extinction at 232 nm (K ₂₃₂) and the peroxide value (PV). Analysis of FAME polymers by HPSEC was also performed to discard samples of advanced oxidation. Results showed that the contents of hydroperoxydienes with respect to the PV were higher for the high linoleic (HL) sample. At the end of the period of slow polymerization (ΔPol ≤ 1 wt%), the content of hydroperoxydienes was found to be 86.0 and 30.7 μg/mg for the HL and high oleic (HO) samples, respectively. Throughout this period, hydroperoxydienes constituted around 90 and 50 wt% of the total hydroperoxides in the HL and HO samples, respectively, suggesting that a significant oxidation of oleic acid also occurred in both samples. The contents of ketodienes and hydroxydienes as a whole constituted 2–3 wt% of the diene compounds analyzed at the end of the period of slow polymerization. Higher contents of ketodienes than of hydroxydienes were found throughout the oxidation time, and the ratio between the contents of ketodienes and hydroxydienes increased with a factor that changed from 1 to 2 throughout the period of slow polymerization.     

壳聚糖/聚乙二醇共混物的相变行为

用TMA（静态热机械分析法）、DSC（差效扫描式量效法）等分析方法研究了壳聚糖和聚乙二醇共混物的相变行为。当共混物中亮聚糖组分含量高于15％、温度高于聚乙二醇熔点时,共混物中的聚乙二醇不融化成液体,仍保持为固体,共混物表现出固态相变行为。TG－DTA（联合热重量-差示热分析法）分析表明该共混物具有较好的效稳定性。     

Thermal Properties,Fracture Toughness and Water Absorption of Epoxy-Palm Oil Blends

Epoxidized palm oil (EPO) was blended with cycloaliphatic epoxide, epoxy novolac and diglycidyl ethers of bisphenol-A. The fracture toughness and thermal properties of epoxy/EPO blends were characterized using single-edge notched bending tests and differential scanning calorimetry. Increased EPO loading improved the fracture toughness (K _IC ) of the epoxy blends. The epoxy blends with higher EPO loading exhibited higher degree of conversion. The glass transition temperature (T _g ) of the epoxy blends shifted to higher temperature as the increasing of DSC heating rate. Water absorption caused T _g reduction of epoxy blends but it was determined that the water molecules absorbed were totally reversible.