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1.
Preparation and properties of ethoxylated fatty methyl ester nonionics 总被引:11,自引:0,他引:11
Ehthylene oxide (EO) cannot react directly with fatty methyl esters that have no active hydrogen. We developed a new synthetic
method, which directly inserts EO into fatty methyl esters (RCOOCH3) to give [RCO(OCH2CH2)nOCH3]. This was achieved by the use of a novel solid catalyst modified by metal cations. Ethoxylates of fatty methyl esters obtained
by this method were homogeneous monoesters and had good properties as nonionic surfactants.
Presented at the AOCS Annual Meeting & Expo in Anaheim, California, April 1993. 相似文献
2.
Influence of catalyst structure on direct ethoxylation of fatty methyl esters over Al-Mg composite oxide catalyst 总被引:6,自引:0,他引:6
During direct ethoxylation of fatty methyl ester over Al-Mg composite oxide catalyst, the activity was nearly proportional
to the total number of active Al acidic sites on the catalyst surface per unit weight of catalyst. Lower active Al acidic
site densities resulted in a narrower ethylene oxide (EO) adduct distribution of obtained ethoxylate. We developed a new catalyst
with a large surface area on which many acidic sites are distributed uniformly by partially poisoning the Al acid sites of
high-Al content Al-Mg composite oxide with alkali. This catalyst was used for direct ethoxylation of fatty methyl esters to
obtain ethoxylated fatty methyl esters with narrow EO adduct distribution efficiently. 相似文献
3.
I. Hama T. Okamoto E. Hidai K. Yamada 《Journal of the American Oil Chemists' Society》1997,74(1):19-24
For the purpose of estimating the reaction mechanism of the direct ethoxylation of a fatty ester in the presence of an Al-Mg
composite oxide catalyst, a labeled fatty methyl ester C11H23CO18OCH3 containing 18O isotope was synthesized and directly ethoxylated. The product was evaluated by gas chromatography-mass spectrometry (GC-MS).
The GC-MS spectra showed that the 18O isotope label was present only in the methoxy group at the molecular end of the ethoxylated fatty methyl ester. This supports
the reaction mechanism of coordination anionic polymerization where the bond between the acyl and methoxy groups of the fatty
methyl ester molecule was broken, caused by the bifunctional effect of the acid-base active sites; an intermediate chemisorption
species was formed; and then ethylene oxide was addition-polymerized sequentially, in parallel. 相似文献
4.
乙氧基化脂肪酸甲酯的性能及丙氧基化改性研究 总被引:4,自引:0,他引:4
以单碳酸或混合酸甲酯为原料,通过一步法乙氧基化反应合成了不同链长的脂肪酸和不同EO数的乙氧基化脂肪酸甲酯(EFME),测定了EFME的物化性能和应用性能。结果表明,EFME具有低成本、低泡等特殊优点,性能依赖EO加成数变化连续可调整,EFME中的封端甲基是导致其性能不同于AEO的最重要的结构因素。用PO对EFME进行化学改性,先加成PO的产品的起泡力更低、流变性更好,与不改性产品相比起泡力降为原先的29%;稳泡性降为原先的22%;黏度降低为原先的44%。说明PO位于分子的亲水端侧较处于疏水端侧对产品的泡沫性和流变性的影响程度更大,通过PO改性可以进一步开发EFME的新用途。 相似文献
5.
I. Hama H. Sasamoto T. Tamura T. Nakamura K. Miura 《Journal of surfactants and detergents》1998,1(1):93-97
Ethoxylated fatty methyl esters (EFME) are nonionic surfactants obtained by direct insertion of ethylene oxide to fatty methyl
esters in the presence of a composite metal oxide catalyst. Results of cumulative skin irritation testing of EFME on guinea
pigs indicate that EFME are less irritating compared to ordinary alcohol ethoxylates (AE). Good skin compatibility of EFME
is further illustrated by an in vitro hemolysis test and an in vitro cytotoxicity test. From the standpoint of environmental properties, EFME are readily biodegradable and are less toxic than
AE. These results indicate the outstanding dermatological compatibility and good environmental compatibility of EFME. 相似文献
6.
Nonionic surfactant properties of methoxypolyoxyethylene dodecanoate compared with polyoxyethylene dodecylether 总被引:4,自引:0,他引:4
Nonionic surfactant properties of methoxypolyoxyethylene dodecanoate [C12-EFME; C11H23CO-(OCH2CH2)
n
CH3] with varying ethylene oxide (EO) adduct distributions were compared with those of polyoxyethylene dodecylether [C12-alcohol ethoxylate (AE); C12H25O(CH2CH2O)
n
H]. The gelling region of C12-EFME was much smaller than that of C12-AE due to the effects of the ester bond and the terminal methyl group. When the EO adduct distribution of EFME is narrowed,
the cloud point and the ability to lower interfacial tension do not change appreciably. Other effects of narrow distribution
on EFME performance include a decrease in the gellation region and better foam breaking and wetting. 相似文献
7.
以十二烷基苯为原料,经氯甲基化、水解及环氧乙基化等步骤得到平均乙氧基(EO)数为9.5的十二烷基苄醇聚氧乙烯醚(LBAEOn)。分别用FTIR和1HNMR表征了产物LBAEOn的结构特征,并用ESI-MS确定了LBAEOn中的EO分布。以表面张力法测得在25℃时LBAEOn的cmc和γcmc分别为1.83×10-6mol.L-1和39.0 mN.m-1;与脂肪醇聚氧乙烯醚(AEO9)和壬基酚聚氧乙烯醚(NPEO10)相比较,除钙皂分散性能大致相当以外,LBAEOn的表面活性较好、发泡力较低、对正辛醇的增溶能力较强和对帆布的润湿性能较差。 相似文献
8.
乙氧基化生产过程中,通过正交试验,找出最优工艺条件,在固定投料量的基础上,调整催化剂用量,增加熟化工艺,延长气提时间,降低产品中游离环氧乙烷(EO)含量,使得下游磺化生产中二恶烷的含量处于较低水平。 相似文献
9.
Methyl ester ethoxylates are a new class of ethylene oxide (EO)-derived surfactants. Little is known about the impact of structural
variations on their performance properties. The effects of carbon chain length, EO content, the degree of unsaturation of
the methyl ester feedstock, and feedstock purity were examined for their impact on both physical properties and surfactant
performance properties. Physical properties examined included surface properties (surface tension, critical micelle concentration,
surface excess adsorption), melting point, water solubility, viscosity, foam stability, color, clarity, and odor. The impact
of molecular structure on performance was examined for various applications, including laundry detergents, dishwashing detergents,
and hard-surface cleaners.
Presented at the AOCS Annual Meeting & Expo, May 1997, Seattle, Washington. 相似文献
10.
脂肪酸甲酯乙氧基化物中未反应脂肪酸甲酯的测定 总被引:1,自引:0,他引:1
采用气相色谱法(GC)测定了不同脂肪酸甲酯乙氧基化物(MEE)中未反应的脂肪酸甲酯的质量分数。以十三酸甲酯为内标,对不同MEE进行了定性和定量分析,同时以十二酸甲酯为标准考察了回收率。实验结果表明:该法相对标准偏差在1.2%以内,回收率大于96%。由测定结果可知:GC法简便、快速、准确率高、重现性好、能准确测定不同MEE中未反应脂肪酸甲酯的质量分数,可作为MEE产品质量监控的方法,也可为MEE新产品、新配方研究与开发提供有效的参考依据。 相似文献
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13.
蓖麻油脂肪酸甲酯乙氧基化物中环氧乙烷分布检测 总被引:2,自引:0,他引:2
蓖麻油脂肪酸甲酯乙氧基化物(CA-MEE)用0.5 mol/L KOH乙醇溶液水解,酯键断裂,考察水解次数和水解时间对水解率的影响及回收率;所得亲水基部分之一的甲基聚乙二醇醚用气相色谱法(GC)测其平均环氧乙烷(EO)加合数及其分布,进而考察EO对酯基和仲羟基的选择性。结果表明:CA-MEE在85℃±1℃、1 h条件下能够完全水解,且实验方法有相当好的回收率。样品CA-MEE-12分离出的甲基聚乙二醇醚部分EO加合数色谱图表明,EO对酯基的选择性(EO在酯基上平均加合数为10.0)远高于其对仲羟基的选择性,而且EO分布很窄。 相似文献
14.
分子结构和温度对油基氧乙烯醚水溶液表面吸附动力学的影响 总被引:1,自引:0,他引:1
使用最大气泡法测定了油基十氧乙烯基醚C18H35O(CH2CH2O)10H(Brij97,C18EO10OH),油基二十氧乙烯基醚C18H35O(CH2CH2O)20H(C18EO20OH)水溶液的动态表面张力(DST),考察了结构及温度对DST的影响,详细表征了DST随时间的变化过程,计算了动态表面张力的参数(n,t^n,γm),结合Word—Tordai方程计算了表观扩散系数(Da)和吸附势垒(Ea)。探讨了上述参数的变化规律。 相似文献
15.
Gemini表面活性剂具有的优良表面活性,使之有望作为三次采油用的表面活性剂。用界面张力仪及HAAKERS600流变仪研究了非离子型Gemini表面活性剂的表面活性及流变特性。结果表明,25℃下,氧乙基数(EO数)分别为8,10,12的3种非离子型Gemini表面活性剂8-NP-8、10-NP-10及12-NP-12的临界胶束浓度(cmc)值分别为:0.99,0.15和0.032 mmol/L;非离子型Gemini表面活性剂的表面活性及cmc值受电解质的影响较小;氧乙基数为12的非离子型Gemini表面活性剂可以使亲水及亲油固体表面的接触角明显降低,水润湿性增强;非离子型Gemini表面活性剂溶液的粘度随剪切速率增加基本保持不变,呈现出牛顿流体的特性。 相似文献
16.
采用间接酯化法,以柠檬酸和乙酸酐为原料,先合成柠檬酸酐,后与醇醚糖苷(含有未反应的脂肪醇醚)反应,合成了醇醚糖苷柠檬酸单酯,再用NaOH溶液、饱和Ca(OH)2水溶液和Mg(OH)2乳浊液中和制得醇醚糖苷柠檬酸单酯二钠盐(MAEG-EC-Na)、醇醚糖苷柠檬酸单酯钙盐(MAEG-EC-Ca)和醇醚糖苷柠檬酸单酯镁盐(MAEG-EC-Mg),对产物的物化性能进行了测定。结果表明,上述3种产品的γcmc变化范围均很小,而柠檬酸单酯二钠盐的cmc最小,柠檬酸单酯盐起泡性能、泡沫稳定性的顺序为MAEG-EC-Mg>MAEG-EC-Ca>MAEG-EC-Na。 相似文献
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18.
Teruhisa Satsuki Kenji Umehara Yuji Yoneyama 《Journal of the American Oil Chemists' Society》1992,69(7):672-677
The detergency properties of α-sulfonated fatty acid methyl esters (α-SFMe) were evaluated and compared to those of conventional
anionic surfactants by using a model heavy-duty detergent formulation. Several physicochemical properties of surfactants were
measured to investigate the effective factors on detergency. α-SFMe showed good detergency performance under various washing
conditions. These results were considered to correlate well with the good adsorption behavior on oils and dispersing capabilities
for particles, as well as with the good solubilization capacity. Solubilization behavior of α-SFMe is discussed in relation
to micelle properties. It is suggested that α-SFMe can form suitable micelles for solubilizing polar oils advantageously,
due to its bulky hydrophilic group. 相似文献
19.
Wiesaw Hreczuch 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(5):511-516
The work investigates the influence of temperature on the reaction kinetics and the consequent change in the distribution of homologues during ethoxylation of fatty acid methyl esters. It was found that temperature‐related kinetics of ethoxylation significantly affects the composition of the products and more narrow distributions of homologues are found with an increase in the reaction temperature from 135 °C to 185 °C. It is suggested that intermolecular complexation of the catalyst cation takes place, thus broadening the distribution of the homologues produced at the lower temperature range and the effect decays with increases in the reaction temperature. The substantial influence of the distribution of homologues on the products' viscosity and solubility is revealed. © 2002 Society of Chemical Industry 相似文献
20.
以含氢硅油(PMHS)、N-甲基-N-烯丙基-2-全氟-2-甲基-3-氧代己酰胺(NF2)和烯丙基聚醚(F6)为原料,在Karstedt催化剂作用下,通过硅氢加成反应制备了氟硅非离子表面活性剂PF2F6;采用FT-IR、1H NMR和19F NMR对产物结构进行了表征,并测定了产物的溶解度、浊点、表面张力和润湿性。结果表明,PF2F6在弱极性溶剂中具有良好的溶解度,在水中的溶解度随着F6物质的量的增大而增大;当n(Si-H)∶n(NF2)∶n(F6)=2∶0.7∶1.3时,临界胶束浓度(cmc)和平衡表面张力(γcmc)最小,其值分别为0.13 g/L和22.8 mN/m;随着反应体系中F6物质的量的增加,PF2F6的浊点增加,而在有机玻璃(PMMA)表面的接触角减小。 相似文献