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1.
Minor proportions of hydroxy (ca. 1%), epoxy (ca. 2%, mostly cis but possibly some trans) and keto fatty acids have been detected in fresh Argemone mexicana seed oil by employing a combination of chromatographic and spectrophotometric techniques.  相似文献   

2.
通过紫外光自由基聚合制备了可生物降解交联网状聚(醚.酯)共聚物。测定了交联聚合物的接触角。研究了交联聚合物的体外降解特性,结果表明,降解时间取决于交联度和疏水程度(聚酯类型),大约从20min到7d。将交联聚合物涂在不锈钢针上,通过测定针穿透橡胶塞时的穿透力,研究了材料的润滑特性。与标准针相比,涂有PPG4000聚合物网络的针穿透力下降了40%,显示了较好的润滑性能。这些材料有可能作为可降解的润滑材料,包覆不同的医用产品,取代现在使用的非降解性硅树脂。  相似文献   

3.
Unsaturated and saturated fatty acids fractions were separated from overused sunflower and olein oils, which are considered to be a waste, in order to use them in the preparation of valuable ethoxylated fatty derivatives with low cost of preparation. Fatty acid fractions were ethoxylated using ethylene oxide gas in the presence of 1% K2CO3 catalyst at 120 and 180 °C for 5, 6 and 7 h. Also fresh stearic acid and a fresh mixture of stearic acid:sunflower oil (1:1 wt/wt) were ethoxylated at 180 °C for 6 h for comparison. Results showed that effective fatty derivatives could be obtained from overused oils which may give an economic retrieval. Also, reaction conditions have different effects on the properties of the produced derivatives where the best results were obtained for samples prepared at 180 °C for 6 and 7 h. Ethoxylating the saturated fatty acids fraction of both overused oils especially olein oil gave better results than those of the unsaturated fraction, the ethoxylated fresh stearic acid and the ethoxylated fresh mixture of stearic acid:sunflower oil (1:1 wt/wt).  相似文献   

4.
乌桕梓油脂肪酸组成分析   总被引:1,自引:0,他引:1  
陶俊杰  陈文伟  高荫榆  洪瑶 《广东化工》2011,38(9):145-145,138
乌柏是我国四大木本油料之一,种子含油量高,乌桕梓油是由种仁榨取所得的液体油脂,是轻工业、食品和国防等行业的重要油源。乌桕梓油甲酯化后,利用100 m×0.25 mm的GC毛细管柱,气相色谱法测定乌桕梓油的脂肪酸组成。测定结果表明:乌桕梓油中饱和脂肪酸占10.68%,以棕榈酸含量最高,占7.52%。不饱和脂肪酸占89.13%,单不饱和脂肪酸占18.63%,以油酸含量最高,占14.55%;多不饱和脂肪酸占70.50%;其中含量最高的为人体所必需的脂肪酸亚油酸和α-亚麻酸,分别占30.77%和39.30%。还含有相当数量天然植物中少有的奇数碳原子脂肪酸十一烷酸,占0.29%。其中月桂烯酸(占3.19%)和十一烷酸未见报道。  相似文献   

5.
The ozonolysis of unsaturated lipids is a process that has been used to generate aldehydes, acids, alcohols, and other biobased chemical intermediates. Reported here is a method that can be used to measure the formation of nonanal and oleic acid during the ozonolysis of unsaturated vegetable oil fatty acids or their methyl esters to indicate the extent of the ozonolysis reaction. Derivatization was performed using boron trifluoride in methanol solution to transform nonanal and oleic acid into nonanal dimethyl acetal and oleic acid methyl ester, respectively. Undecanal and 10‐heptadecenoic acid were used as internal standards and separation was performed using gas chromatography coupled with a flame ionization detector. The method was validated by performing a standard addition procedure in which nonanal or oleic acid standards were spiked into samples collected during the ozonolysis of oleic acid or canola oil fatty acid methyl ester (FAME). Linear regression results indicated that the measured nonanal and oleic acid are in good agreement with the actual amounts of nonanal and oleic acid added to the sample with at least 98 % recovery. The application of the method was demonstrated by the successful measurement of nonanal and oleic acid formed throughout the ozonolysis process for high oleic canola oil FAME.  相似文献   

6.
植物油具有生物可降解性、低挥发性、优良的润滑性和良好的黏温性,但植物油存在热氧化安定性差、低温性能差等缺陷,不能直接作润滑油和润滑添加剂应用,需要对其进行改性。常用化学改性方法有选择性氢化、酯交换和环氧化等,其中环氧化-开环反应引入活性基团和双键上的自由基加成反应是合成植物基润滑油添加剂的两种有效的改性方法。最后,就改性植物油用作可降解润滑油基础油和添加剂提出了研究方向并做了展望。  相似文献   

7.
8.
Free fatty acids (FFA) in crude rice oil were selectively and stoichiometrically derivatized to fatty acid N,N-dimethylamides (FADMA) by catalytic condensation at 45 °C, and then esterified fatty acids (eFA) were directly converted to fatty acid methyl esters (FAME) at 37 °C. The mixture of FADMA and FAME formed in a single test tube was injected into the capillary column of a gas chromatograph (GC). No mutual contamination occurred between FFA and eFA, and reliability of the method was confirmed by comparison between GC data obtained by this method and by a conventional isolation method. The advantages of the present method are that no FFA isolation procedures are required, the reactions proceed under mild temperature conditions, and FFA and eFA can be analyzed simultaneously by GC.  相似文献   

9.
Hydroxy sulfonated fatty acid ester surfactants, having the general formula RCOOCH2CHOHCH2SO3M (where M is alkali or other metal) have been synthesized from four saturated (C12 to C18) and four unsaturated (C18?, C182?, C183? and ricinoleic) fatty acids. Comparative evaluation of their surface active properties as well as some analytical methods for determining their composition and their identification and separation have been described.  相似文献   

10.
Sludges obtained as tank settlings from solvent-extracted rice bran oil have been shown to be rich sources of wax and fatty acids. The wax content is variable, being about 18% in one sample and about 39% in a second sample of sludge. The wax was bleached to light colour. The crude wax shows good compatibility with other types of waxes. The oil fraction of sludges is high in free fatty acids (over 70%), about three fourth of which could be vacuum-distilled directly to yield light-coloured fatty acids.  相似文献   

11.
《分离科学与技术》2012,47(19):2685-2703
Abstract

The separation of fatty and resinic acidic fractions from crude tall-oil soap solutions with n-heptane by the technique of dissociation extraction is discussed. The theory of the overall process is supported by a systematic study developed to cover the high selectivity demonstrated in the differential solubility and the aptness between fatty and diterpenic acids to both liquids phases. To study the main factors affecting those liquid-liquid extraction systems and the amphiphilic behavior of such molecules involved, sodium salts aqueous solutions of crude tall oil and synthetic mixtures as molecular acidic models were used.  相似文献   

12.
针对难降解废弃塑料对自然环境造成的影响,采用生物基原料制备全生物降解材料,从根源上解决塑料污染.介绍了蛋白复合膜、淀粉复合膜和多糖复合膜3种生物基降解薄膜的性能及应用方向,为推动全生物降解材料的发展提供参考.  相似文献   

13.
尿素包合法分离橡胶籽油中的多价不饱和脂肪酸   总被引:8,自引:0,他引:8  
肖红卫  高珏 《精细化工》2002,19(1):12-14,17
用尿素包合法从橡胶籽油混合脂肪酸中分离多价不饱和脂肪酸 ,用正交设计实验法对分离工艺进行研究 ,其最佳分离条件是 :原料配比为m(混合脂肪酸 )∶m(尿素 )∶m(乙醇 ) =1 0 0∶1 5∶1 8,回流时间 12 0min。经一次尿素包合法分离即可得到多价不饱和脂肪酸质量分数大于90 %的产品 ,实验收率大于 35 %  相似文献   

14.
Gas-liquid chromatographic analysis of methyl esters of two samples of castor oil gave the following (as wt %): palmitate 1.2, 0.9; stearate 0.7, 1.2; arachidate 0.3, 0.2; hexadecenoate 0.2, 0.2; oleate 3.2, 3.3; linoleate 3.4, 3.7; linolenate 0.2, 0.2; ricinolE'ate 89.4, 89.0; and dihydroxystearate 1.4, 1.3. Oxidative cleavage of purified methyl ricinoleate indicated that the double bond was exclusively in the 9舑10 position. Castor oil glycerides were fractionated in a 100-tube CCD apparatus using 90% ethanol and commercial hexane as solvents. Analysis of pooled fractions showed (as mole %) triricinolein 68.2, diricinoleins 28.0, mono-ricinoleins 2.9 and nonricinoleins 0.9. These results coupled with lipase hydrolysis of the whole oil and of the fractions agree well with the distribution pattern proposed by Vander Wal.  相似文献   

15.
有机硅互穿聚合物网络   总被引:1,自引:0,他引:1  
概述了互穿聚合物网络的几种类型及其制备方法 ,并以相容性和相分离的关系为基础介绍了表征相形态和相尺寸的手段 ,重点综述了含有机硅的互穿聚合物网络的合成和性能 ,以及现有的和潜在的应用  相似文献   

16.
Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils—safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil—were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%–20.0%), oleic acid (C18:1; 6.2%–71.1%) and linoleic acid (C18:2; 1.6%–79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%–695.7% ERDI), PUFAs (10.6%–786.8% ERDI), n-3 FAs (4.4%–117.1% ERDI) and n-6 FAs (1.8%–959.2% ERDI), expressed in % ERDI of 1 g oil to energy recommended dietary intakes (ERDI) for total fat (ERDI—37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% ERDI) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman’s correlations.  相似文献   

17.
Lead tetraacetate in the presence of catalytic amounts of Cu(II) has been shown to be very effective for the conversion of carboxylic acids to terminal olefins with one less carbon atom. The advantage of this method is that a reaction temperature of only 80°C is needed and it yields very few side products. This low reaction temperature makes it ideal for the decarboxylation of drying oil derived fatty acids which contain very reactive internal unsaturation. This paper describes the use of lead tetraacetate to produce 17 carbon terminal polyolefins from unsaturated fatty acids with pyridine and lithium acetate as catalyst. The products of these reactions were analyzed by IR for disappearance of the carbonyl peak and appearance of peaks due to terminal unsaturation. IR spectra gave very little evidence of isomerization of the cis internal double bonds to the trans isomers.  相似文献   

18.
The seed oil of Piper nigrum has the following fatty acid composition: capric (4.1%), lauric (2.5%), myristic (3.1%), palmitic (27.2%), stearic (7.3%), oleic (29.9%), linoleie (7.7%), vernolie (7.7%), malvalie (6.3%), and sterculic (4.2%) acids.  相似文献   

19.
张琳  林波  袁怡君 《广东化工》2011,(8):133-134
用乙醚萃取海南油棕果肉中的油脂,油脂中的脂肪酸采用氢氧化钾-甲醇溶液进行甲酯化后,利用气相色谱-质谱联用技术(GC—MS)对其中的脂肪酸成分进行分析。结果分离鉴定出4种脂肪酸成分,它们分别是棕榈酸(45.62%)、油酸(37.70%)、亚油酸(8.39%)、硬脂酸(8.29%)。其中不饱和脂肪酸高达46%以上,有进一步开发利用的潜力。  相似文献   

20.
Enrichment of the omega-3 (n-3) fatty acids of refined hoki oil (RHO) intact triglycerides (TG) and via free fatty acids (FFA), was carried out in the present study using established methods of dry fractionation (DF), low temperature solvent crystallization (LTSC) and urea complexation (UC) and positional distribution of fatty acids in the intact TG was determined by Nuclear Magnetic Resonance (NMR) analysis. Results showed that n-3 fatty acids were enriched in liquid fractions of all methods except DF, where the highest concentration was obtained via the UC method (83.00 %). The FFA form of the oil produced a higher concentration (40.81 %) of n-3 fatty acids via the LTSC method compared to the TG form (31.50 %). The percentages of the total saturated fatty acid (SFA) in the liquid fractions in all methods were lower, ranging from 1.60 % (UC) to 21.44 % (DF) compared to the RHO parent oil (24.05 %). The percentages of total monounsaturated fatty acids (MUFA) in the liquid fractions were similar to the solid fractions except for the UC method where total MUFA was six times higher in the solid fraction. In LTSC-FFA and UC methods, the enrichment factor for EPA was lower, ranging from 1.61 (LTSC-FFA) to 2.83 (UC), than DHA which ranged from 1.64 (LTSC-FFA) to 3.88 (UC). EPA was preferentially located at the sn-1,3 position and DHA was significantly located at the sn-2 position which is the favoured location for intestinal digestion.  相似文献   

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