脂肪酸三乙醇胺单酯琥珀酸酯磺酸盐的制备及表面活性

以三乙醇胺、长链脂肪酸为原料,制得脂肪酸三乙醇胺单酯(FTME),再经磺化反应合成了4种脂肪酸三乙醇胺单酯琥珀酸酯磺酸盐(FTMS)两性表面活性剂,以月桂酸、棕榈酸、硬脂酸、油酸为脂肪酸合成的FTMS分别命名为FTMS-1、FTMS-2、FTMS-3、FTMS-4。分别用碱性亚甲基蓝法和酸性溴酚蓝法验证了产物的离子性,并考察了FTMS结构中的烷基链长度及其不饱和度对表面张力、Krafft点、样品液粒径及粒径分布、乳化能力的影响。结果表明:产物显示出两性离子的特征,随着脂肪链碳数增加,其Krafft点升高,平均粒径逐渐增大,但脂肪链中的不饱和双键有助于Krafft点的降低和粒径的减小。FTMS-1和FTMS-4具有优异的表面活性。其中,FTMS-1的临界胶束质量浓度(CMC)为52.97 mg/L,表面张力γCMC为36.1 m N/m,其乳化能力与脂肪醇聚氧乙烯醚(AEO-9)相当且优于十二烷基磺酸钠。     

以三乙醇胺硼酸酯为前驱体制备大颗粒六方氮化硼

以三乙醇胺和硼酸为原料,甲苯为带水剂,合成了三乙醇胺硼酸酯;以三乙醇胺硼酸酯为前驱体在氨气气氛中烧结制得六方氮化硼颗粒。采用FTIR、XRD、SEM、NMR对中间产物和最终产物进行了表征。结果表明:以三乙醇胺硼酸酯为前驱体,在1 200℃下烧结4 h,可制得质量分数为94.3%、六方晶型良好,粒径达17.52μm的六方氮化硼颗粒;经过2 000℃高温精制后的六方氮化硼颗粒具有较高的结晶度和致密度,质量分数可达到98.5%,粒径可达到30μm以上。     

以三乙醇胺硼酸酯为前驱体制备大颗粒六方氮化硼

以三乙醇胺和硼酸为原料,甲苯为带水剂,合成了三乙醇胺硼酸酯,在最佳工艺条件下以三乙醇胺硼酸酯为前驱体在氨气气氛中烧结制得六方氮化硼颗粒。采用IR、XRD、SEM、NMR等测试方法对中间物和产物进行了表征,确定了中间物及产物的组成、物相、粒度及形貌。研究结果表明：以三乙醇胺硼酸酯为前驱体在1200℃烧结4h,可制得高纯度、晶型良好,粒径在20μm左右的六方氮化硼颗粒。经过高温精制后的六方氮化硼颗粒具有较高的结晶度和致密度,其粒径可以达到30μm以上,纯度为98.5%。     

多支化阳离子聚氨酯表面活性剂的制备与性能

摘 要：为研究具有多条烷基长链的多支化阳离子聚氨酯表面活性剂的结构控制方法及其构效关系，以异佛尔酮二异氰酸酯（IPDI）、N-甲基二乙醇胺、十六醇和溴代烷烃为原料，制备了一系列多支化长链烷基季铵型聚氨酯表面活性剂（SC2、SC3、SC4）。产物结构经红外光谱、凝胶色谱和核磁共振氢谱进行确证。对其临界表面张力、Krafft点、发泡性、乳化性及耐盐性进行了测试。由于单体、产物与溶剂的极性差异，导致具有三支长链烷基的阳离子聚氨酯表面活性剂（SC3）无法按配方设计获得，其产物为SC2与SC4的混合物。具有双十六烷基的阳离子聚氨酯表面活性剂（SC2）的临界表面张力（γCMC）为23.61mN/m，对应的临界胶束浓度（CMC）为0.30×10-3mol/L，Krafft点为23℃；具有四支十六烷基的阳离子聚氨酯表面活性剂（SC4）的γCMC为30.35mN/m，CMC为0.25×10-3mol/L，Krafft点为41℃；同时，产物具有较高的表面活性和良好的乳化、发泡、耐盐性能。结果表明，对于具有复杂结构的表面活性剂而言，基于异氰酸酯与羟基反应的制备方法简单可靠。 关键词：聚氨酯表面活性剂；多支化；阳离子；构效关系     

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。     

间苯二甲酸酯Gemini表面活性剂的合成及性能

N,N-二甲基乙醇胺与间苯二甲酰氯反应获得二(N,N-二甲基胺基乙基)间苯二甲酸酯,再分别与溴代正十二烷和溴代正十六烷制得两种含酯基Gemini阳离子表面活性剂(C12-O-C12、C16-O-C16)。采用IR、1 H NMR、元素分析表征了其结构。测定了其临界胶束浓度(CMC)分别为6.91×10-4 mol/L、7.07×10-5 mol/L;平衡表面张力(γCMC)分别为41.9 mN/m、40.8 mN/m;Krafft点分别为0℃、43℃。并研究了其乳化性、泡沫性质等。     

马来酸三乙醇胺双酯的合成及其对水泥性能的影响

本文以马来酸酐、三乙醇胺为原料,通过两者酯化反应合成马来酸三乙醇胺双酯,探讨反应温度、反应时间、物料摩尔比对其酯化程度的影响规律;并考察合成产物在不同掺量下对水泥力学性能(强度)和水化特性(水化热、化学结合水、微观形貌)的影响.研究结果表明:反应温度120℃,反应时间4h及马来酸酐和三乙醇胺的摩尔比为1:2时,马来酸酐与三乙醇胺的酯化程度最高,酯化率高达80.22％;在此反应条件下合成的马来酸三乙醇胺双酯的掺量为0.02％时,对水泥的力学性能和水化性能作用效果最佳;与三乙醇胺相比,两者对水泥早期强度的作用相当,但马来酸三乙醇胺双酯对水泥后期水化有明显促进作用,对水泥后期强度的激发优于三乙醇胺.     

马来酸三乙醇胺酯对水泥水化的影响

为克服三乙醇胺早强剂对水泥抗折强度和后期强度的影响,合成了马来酸三乙醇胺酯,并通过背散射电子成像(BSE)和BET分析,研究了马来酸三乙醇胺酯对水泥水化程度、C-S-H含量和水泥水化28 d分形维数的影响。结果表明:马来酸三乙醇胺酯可促进水泥水化尤其是水泥中硅酸盐相的水化;复掺马来酸三乙醇胺酯和聚羧酸减水剂,可显著提高水泥水化产物中C-S-H的含量;三乙醇胺降低了水泥石28 d的分形维数,马来酸三乙醇胺酯单掺及与聚羧酸减水剂复掺则使水泥石28 d的分形维数提高。由此可见,马来酸三乙醇胺酯作为增强型水泥早强剂具有广阔的应用前景。     

一种梳状表面活性剂的合成及应用

以β-蒎烯/马来酸酐共聚物为主链,接枝聚乙二醇单甲醚,合成一种梳状高分子表面活性剂,并对产物进行了表征。讨论了反应物相对分子质量、反应物配比及反应时间对表面张力的影响,采用相反转乳化技术将其应用于松香酯乳液。结果表明,产物具有良好的表面活性,采用相对分子质量为6 300的β-蒎烯/马来酸酐共聚物为主链,接枝聚乙二醇单甲醚-500,2种反应物按照酸酐与羟基的摩尔比为1∶1进行反应,反应时间为12~16 h时,反应产物降低水溶液表面张力的效果最好,产物制备松香酯乳液效果良好。     

松香基可分解型表面活性剂的合成及性能

以歧化松香为原料,经酰氯化、酯化、磷酸化、成盐等反应,合成4种可分解型松香基表面活性剂(Ⅰ、Ⅱ、SAA-Ⅲ、SAA-Ⅳ)。利用FTIR和NMR对其进行了结构表征,并考察了其表面和分解性能。结果表明,Ⅰ、Ⅱ、SAA-Ⅲ、SAA-Ⅳ的临界胶束浓度(CMC)分别为4.69×10–3、5.15×10–3、2.65×10–3和1.71×10–3 mol/L,对应的表面张力(γCMC)分别为48.2、41.4、34.6和33.2 m N/m。Ⅰ、Ⅱ、SAA-Ⅲ、SAA-Ⅳ在乳化体系(石蜡/水)中分出10 m L水的时间分别为11、128、90和98 s,初始起泡高度分别为16.0、18.5、18.0和23.0 mm,5 min后泡沫高度变化依次为6.0、4.0、4.0和11.5 mm;松香酯表面活性剂Ⅱ具有优异的乳化性能,而松香磷酯表面活性剂SAA-Ⅳ具有优异的起泡性能。松香基酯表面活性剂Ⅰ和Ⅱ的浊点分别约为90和80℃,松香磷酯表面活性剂SAA-Ⅲ和SAA-Ⅳ的Krafft点分别在30~40℃和50~60℃,且浊点和Krafft点均随分子链的增长而增大。室温强酸条件下的酸水解实验表明,4种表面活性剂均具有可分解性。     

Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia

The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16–20th weeks, 26–30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α‐linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n‐6 fatty acids were higher (p < 0.05) at 16–20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n‐3, 22:6n‐3, 24:1n‐9, MUFA, and total n‐3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n‐3 and 24:1n‐9 at 16–20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.     

An Empirical Equation for Estimation of Kinematic Viscosity of Fatty Acid Methyl Esters and Biodiesel

Kinematic viscosity (µ) is an important physical property of fatty acid methyl esters (FAME) and biodiesel. In this work, the Martin's rule of free energy additivity is extended to cover the kinematic viscosity of saturated and unsaturated FAME commonly found in nature. The proposed model can also be extended to estimate kinematic viscosity of biodiesel. The kinematic viscosity of a FAME or a biodiesel can be easily estimated from its carbon number (z), number of double bonds (n_d) at different temperatures (T) without a prior knowledge of the viscosity of individual FAME. Both z_ave and n_d(ave) can be derived from its fatty acid composition. Thus, kinematic viscosity of biodiesel at temperatures between 20 and 100 °C and at atmospheric pressure can be estimated. The average absolute deviation (AAD) estimated at 20–100 °C for saturated, unsaturated FAME, biodiesels and biodiesel blends are 4.15, 3.25, 6.95 and 2.79 %, respectively. The biodiesels collected in this study (191 data points) have the z_ave and n_d(ave) between 14.10 and 17.96 and 0.21–1.54, respectively. The standard deviation was 0.249. The proposed model would be good for estimation of viscosity of biodiesel containing normal fatty acids, generally found in biodiesel feed stocks.     

Synthesis of Biodiesel via Deoxygenation of Stearic Acid over Supported Pd/C Catalyst

High catalytic activity was achieved in the deoxygenation of stearic acid in dodecane in a temperature range of 270–300 °C under 17 bar helium over palladium on nanocomposite carbon Sibunit. Besides n-heptadecane, which was obtained previously in this reaction with palladium on activated carbon, n-pentadecane was also formed in significant amounts.     

藻类花生四烯酸的提取工艺

花生四烯酸作为一种重要的保健、营养品,越来越受到人们的重视。从鱼油、真菌丝、微藻中都可以提取花生四烯酸,但这些工艺都有着明显的缺点。设计了一种从藻类提取花生四烯酸的新工艺过程。     

Alteration of Serum Phospholipid n-6 Polyunsaturated Fatty Acid Compositions in Nonalcoholic Fatty Liver Disease in the Japanese Population: A Cross-Sectional Study

We performed a cross-sectional study on 215 Japanese employees aged 20–68 years to investigate the association between NAFLD and serum phospholipid fatty acid composition. NAFLD was diagnosed by ultrasonography. The fatty acid composition between the control and NAFLD groups was compared, and the inverse probability of treatment weighting (IPTW) was performed to eliminate each confounding effect of sex, smoking status, BMI, insulin resistance, dietary cholesterol, and salt intake. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the NAFLD prediction accuracy of fatty acids. Seventy-one subjects were diagnosed with NAFLD. Their serum phospholipid dihomo-γ-linolenic acid (DGLA) level was significantly higher after adjusting for each variable using IPTW. In the ROC analysis, the ratio of ARA to DGLA had an area under the curve (AUC) of 0.763. By combining the ratio of ARA to DGLA with the ratio of AST to ALT, AUC increased to 0.871. In conclusion, NAFLD subjects in a Japanese working population have higher serum phospholipid DGLA. Results of the IPTW and ROC analysis indicated that serum PL DGLA and the ratio of ARA to DGLA provide diagnosis information on the fatty liver that is different to AST and ALT and improve the accuracy of fatty liver prediction, owning potential value as serum biomarkers.     

A Comprehensive Evaluation of the Density of Neat Fatty Acids and Esters

Density is one of the most important physical properties of a chemical compound, affecting numerous applications. An application in the case of fatty acid esters (biodiesel) is that density is specified in some biodiesel standards. In the present work, the density of fatty acid methyl, ethyl, propyl, and butyl esters as well as triacylglycerols in the C₈–C₂₄ range was determined in the range of 15–40 °C with a densitometer utilizing the oscillating U-tube technique. Literature data on density are compiled and compared, showing that data for these compounds are incomplete with discrepancies existing in some cases. Besides known effects such as density decreasing with increasing chain length and increasing saturation, it is shown that trans fatty compounds exhibit lower density than cis fatty compounds. Density data for several saturated odd-numbered, C₁₈, as well as C₂₀ and C₂₂ polyunsaturated fatty esters are reported for the first time. The density contribution of compounds with high melting points is predicted. An equation is given for the calculation of the density of mixtures.     

Growth Hormone Secretagogue (A233) Improves Growth and Changes the Tissue Fatty Acid Profile in Juvenile Tilapia (Oreochromis niloticus)

Growth hormone (GH) release is a process that is well regulated by several factors, including GH secretagogues. GH can mediate the regulation of the fatty acid level and composition. The aim of this study was to determine the effect of a synthetic GH secretagogue peptide (A233) on the growth and fatty acid composition in tilapia (Oreochromis niloticus). To address this objective, we administrated a diet supplemented with A233 to juvenile tilapia for 60 days. The group fed with a diet supplemented with 600 μg of A233 per kg of feed increased in weight (4.81 ± 0.09 g) and specific growth rate (2.49 ± 0.03%/day) compared to the control diet group (3.63 ± 0.08 g, 2.07 ± 0.04%/day; respectively) (p < 0.001). In the muscle, the total lipids for the control diet group were higher than that in the group fed with 600 μg of A233 per kg feed; however, no differences were detected in the liver. In both tissues, the patterns of fatty acid composition and content were generally similar, with some exceptions. Tilapia fed with 600 μg of A233 per kg of feed showed, in liver and muscle, a significantly higher composition and content of n‐3 polyunsaturated fatty acids (such as 20:5n‐3, 22:5n‐3, 22:6n‐3) and n‐3/n‐6 PUFA than animals fed with the control diet. To our knowledge, this is the first report on the the effects of natural or synthetic GH secretagogues (GHS) on fatty acid composition, implying an increase in the nutritional quality of the tilapia.     

Preparation and properties of fully esterified erythritol

Pure tetraesters of erythritol with C₁₀, C₁₂, C₁₄, C₁₆, C₁₈ saturated, and C_18:1 unsaturated (oleoyl) fatty acyl chains have been prepared for the first time and characterized using the acylating systems fatty acid/N,N′‐dicyclohexylcarbodiimide/4‐dimethylaminopyridine (DMAP), fatty acid anhydride/DMAP, fatty acyl chloride/pyridine, and fatty acyl chloride/boron trifluoride etherate. For the first three systems the yields were in the range of 80–90% while the fatty acyl chloride/pyridine system has the advantage of lower cost. The fatty acyl chloride/boron trifluoride etherate system gave lower (ca 70%) yields of the tetraesters. The tetraesters of erythritol may have applications analogues to those of triglycerides. In addition, new applications can be envisaged for these compounds, as a result of their differences in physical, chemical, and biochemical properties compared to triglycerides. Practical applications: The tetraesters of erythritol with saturated fatty acyl chains may have applications analogous to those of saturated triglycerides. However, tetraesters with unsaturated fatty acid chains may have greater prospects of having industrial uses after doing chemistry on the carbon–carbon double bonds.