C_(10)~C_(14)烷基糖苷的合成及其作为乳化剂的应用

采用直接法合成了碳链长度为C10~C14的烷基糖苷(APG),用红外光谱对产品结构进行了表征,研究了烷基糖苷浓度及碳链长度对产品表、界面性质的影响。结果表明:随烷基糖苷浓度增大,水溶液表面张力、柴油-水界面张力降逐渐降低,而起泡性、泡沫稳定性逐渐增强。烷基糖苷碳链越长,临界胶束浓度(cmc)值越低;水溶液表面张力、柴油-水界面张力越低,起泡性、泡沫稳定性越强。基于烷基糖苷良好的表、界面性质,将其作为乳化剂制备成乳液,并与常见非离子表面活性剂OP-10制备的乳液进行了对比。烷基糖苷乳化性随浓度增大、碳链长度增长而增强;乳液微观形态表明不同碳链烷基糖苷形成乳状液稳定性、液滴均一性、填充性均优于OP-10稳定的乳液;稳定时间对乳液微观形态影响不大。所合成烷基糖苷中性能最优的为C14APG。     

烷基聚葡糖苷表面活性剂形成微乳液的研究

以烷基聚葡糖苷(APG或CiGi)为表面活性剂，C4～C6正构醇为助表面活性剂，采用肉豆蔻酸异丙酯为油相，与水一起得到微乳液体系。研究了在不同烷基链长度的醇作用下，不同烷基碳链长度的烷基聚葡糖苷形成微乳液体系的拟三元相图以及δ—γ相图，并用HLB方程计算了微乳液界面的一些重要参数。发现使用较长碳链的醇以及用较长碳链的APG均有利于单相及中相微乳液的形成，并对此进行了解释，同时确定了单相微乳液效率最高的体系。     

烷基酰胺磷酸酯甜菜碱的合成与应用

以Ｎ，Ｎ－二甲基丙二胺与不同碳链长度脂肪酸甲酯缩合制得烷基酰胺丙基二甲基叔胺，进一步与２－羟基－３－氯丙磷酸酯反应，制复纱列新型烷基酰胺磷酸酯甜菜碱。该系列产品具有优良的应用性能。     

烷基木糖苷物化性能研究

分别对不同长度碳链和平均聚合度(DP)的烷基木糖苷(AX)进行性能评价,结果表明,AX可将水的表面张力降低到26 mN/m以下,随碳链长度增加,AX临界胶束浓度(cmc)减小,饱和吸附量(Гmax)降低,且Гmax高于相同碳链的烷基葡糖苷(APG),AX的发泡力、泡沫稳定性、抗硬水能力及润湿性能均优于相同碳链的APG。随DP的增大,AX平衡表面张力(γcmc)及cmc均增大,Гmax呈降低趋势,DP对发泡力的影响有限,DP的降低使得AX的抗硬水能力、润湿力和乳化能力有所提高。     

二烷基乙氧基硫酸钠阴离子双子表面活性剂的合成及其表面活性

为研究阴离子双子表面活性剂结构与表面活性的关系,以不同碳链的脂肪醇、环氧氯丙烷、不同的二醇等为原料,通过三步反应合成出一种间隔基为乙氧基的阴离子双子表面活性剂二烷基硫酸钠,得到不同长度碳链和间隔基的4种双子表面活性剂,同时对部分合成条件进行了优化,确定了烷基单缩水甘油醚所用催化剂为苄基三乙基氯化铵以及烷基低聚二醇的最佳反应温度为80℃。核磁共振氢谱和傅立叶变换红外光谱证实了它们及其中间产品的结构。部分产品最小表面张力低于30 mN/m,临界胶束浓度低于0.1 mmol/L,具有良好的表面活性。实验表明,随着碳链的增长和间隔基长度的增加,其CMC降低,间隔基长度的增加使am in变大,但其γCMC变化不大。     

磷钨酸烷基甜菜碱催化氧化燃料油脱硫的性能

以磷钨酸烷基甜菜碱为相转移催化剂,双氧水为氧化剂,在乳液体系下,催化氧化脱除燃料油中的硫化物,研究了磷钨酸十四烷基二甲基甜菜碱、磷钨酸十六烷基二甲基甜菜碱以及磷钨酸十八烷基二甲基甜菜碱的催化性能,考察了催化剂用量、制乳时间、制乳转速以及氧硫比对脱硫效果的影响。结果表明,烷基甜菜碱的烷基链越长,催化效果越好;在催化剂的用量为0.003（剂油比）、制乳时间8min、制乳转速2500r/min、氧硫比为11的条件下,脱硫率可达到91.23%。     

α-长链烷基甜菜碱在皂类产品中的应用性能研究

研究了两性表面活性剂α-长链烷基(C10,C14)甜菜碱在皂类产品中的应用性能。结果表明,皂产品中复配α-长链烷基甜菜碱后,产品的润湿力和抗硬水性能明显改善,对皮肤的刺激性显著降低,但对皂的泡沫性能无明显影响。     

无机粘土的烷基铵盐改性及NBRCNs的结构与性能研究

采用长链脂肪族季铵盐改性有机粘土的方法,研究了烷基铵盐改性剂的碳链长度及配比对无机粘土(MMT)改性效果的影响。结果表明,同一改性剂配比下,由不同碳链长度的烷基铵盐改性剂改性MMT制备的丁腈橡胶/粘土纳米复合材料(NBRCNs)的微观结构、力学性能和分散相态不同,碳链长度适中的十二烷基三甲基溴化铵(CTAB)改性效果较好,碳链长度较长或较短都不利于MMT的改性。对于碳链长度较短的二十二烷基三甲基溴化铵(DTAB),当DTAB用量增加,粘土片层间距增大,力学性能提高。对于碳链长度较长的十八烷基三甲基溴化铵(STAB),STAB用量降低有助于扩大粘土片层间距和提高力学性能。     

α－长链烷基甜菜碱应用性能研究

研究了新型两性表面活性剂α-长链烷基甜菜碱（C10、C12）的应用性能,并与目前常用两性表面活性十二烷基二甲基甜菜碱（BS-12）进行了对比。结果表明,α-癸基甜菜碱KP点与BS-12相当,泡沫性能优于BS-12,润湿力、去污力低于BS-12;α-十二烷基甜菜碱的泡沫性能、润湿力、去污力均优于BS-12。     

N-酰基苯丙氨酸钠表面活性剂的合成和性能研究

以十二酰氯、十四酰氯、十六酰氯和苯丙氨酸为原料,肖顿鲍曼法合成了3种不同碳链长度的N-酰基苯丙氨酸钠表面活性剂:N-十二酰基苯丙氨酸钠(C_(12)PheNa)、N-十四酰基苯丙氨酸钠(C_(14)PheNa)和N-十六酰基苯丙氨酸钠(C_(16)PheNa)。通过红外光谱(FTIR)、核磁共振氢谱(¹H NMR)对产物的结构进行了表征。考察了三种表面活性剂的表面活性、泡沫、乳化、润湿性能。结果表明,随着碳链长度的增加(C_(12)～C_(16)),N-酰基苯丙氨酸钠表面活性剂的临界胶束浓度(cmc)由0.15 mmol/L减少至0.02 mmol/L,对应的表面张力(γ_(cmc))由34.56 mN/m降低至31.52 mN/m;随着烷基碳链的增长,乳化性能越好,润湿性能越差;起泡性能随着烷基链的增加呈现先增加后减少,泡沫稳定性随着烷基链的增加而增加。     

Alteration of Wax Ester Content and Composition in Euglena gracilis with Gene Silencing of 3‐ketoacyl‐CoA Thiolase Isozymes

Euglena gracilis produces wax ester under hypoxic and anaerobic culture conditions with a net synthesis of ATP. In wax ester fermentation, fatty acids are synthesized by reversing beta‐oxidation in mitochondria. A major species of wax ester produced by E. gracilis is myristyl myristate (14:0‐14:0Alc). Because of its shorter carbon chain length with saturated compounds, biodiesel produced from E. gracilis wax ester may have good cold flow properties with high oxidative stability. We reasoned that a slight metabolic modification would enable E. gracilis to produce a biofuel of ideal composition. In order to produce wax ester with shorter acyl chain length, we focused on isozymes of the enzyme 3‐ketoacyl‐CoA thiolase (KAT), a condensing enzyme of the mitochondrial fatty acid synthesis pathway in E. gracilis. We performed a gene silencing study of KAT isozymes in E. gracilis. Six KAT isozymes were identified in the E. gracilis EST database, and silencing any three of them (EgKAT1‐3) altered the wax ester amount and composition. In particular, silencing EgKAT1 induced a significant compositional shift to shorter carbon chain lengths in wax ester. A model fuel mixture inferred from the composition of wax ester in EgKAT1‐silenced cells showed a significant decrease in melting point compared to that of the control cells.     

Effect of alkyl carbon chain length and ethylene oxide content on the performance of linear alcohol ether sulfates

A series of linear alcohol ether sulfates varying in alkyl carbon chain length and ethylene oxide content was evaluated with respect to surface activity, viscosity, foaming, and detergency. Performance data agree well with surface property data. A low level of EO is best in terms of effectiveness and efficiency in lowering surface tension, which is why a low-mole ether sulfate salt-thickens better, produces foam which is more tolerant of soil, and gives good detergency performance. A lauryl-range alkyl carbon chain length is best for foaming and salt-thickening, but a higher carbon chain length appears to be better for detergency performance.     

复合改性膨润土的制备及吸附苯胺的特性

选用不同碳链长度及不同类型的表面活性剂与聚合羟基铝对膨润土进行复合改性,表明长碳链表面活性剂制备的复合改性样品相对于短碳链表面活性剂制备的复合改性样品对苯胺有较好的吸附效果,阴离子表面活性剂制备的复合改性样品比阳离子表面活性剂制备的复合改性样品对苯胺有更好的吸附效果。采用正交试验得到的最优复合改性样品吸附苯胺,表明样品对苯胺的吸附符合准二级动力学模型(R2≈1),粒内扩散并不是控制吸附的惟一限速步骤,Freundlich等温线模型比Langmuir等温线模型更适合描述吸附过程,吸附过程为吸热物理过程(△Hθ=9.39 k J·mol-1)。     

特殊结构的有机硅表面活性剂

介绍了聚醚改性支链硅油、乙烯氧基聚醚改性硅油、聚醚封端的长链烷基硅油、甘油醚与聚醚共改性硅油、含甜菜碱基的两性有机硅表面活性剂的性能、结构及合成方法。     

The effect of homolog distribution on sodium alcohol sulfate solution viscosity

Several compositional factors influence the viscosity of fatty alcohol sulfate solutions. The effects of free oil and inorganic salts on viscosity are known by most sulfators. Each builds viscosity as its level is increased. The relation between viscosity and alkyl sulfate homolog distribution is more subtle and often overlooked. Some synthetic alcohol manufacturers have the flexibility within the coconut alcohol range to vary the lauryl, myristyl, and cetyl alcohol composition. Mixtures containing high lauryl and cetyl alcohol content yielded alkyl sulfates having low viscosities. Mixtures of lauryl and myristyl alcohol gave high viscosity alkyl sulfates. When restricted to compositions containing all three alcohols, the viscosity of the sodium alkyl sulfate derivative was shown to be dependent on the myristyl sulfate content. Solutions having high myristyl sulfate levels had high viscosities. A. limited solubility study of different sodium lauryl, myristyl, and cetyl alcohol sulfate solutions was made.     

短侧链全氟磺酸膜材料

提高运行温度能够克服氢燃料电池面临的许多困难,短侧链全氟磺酸膜在提高燃料电池性能方面具有很大的潜力。本文总结并比较了不同侧链长度的全氟磺酸膜在离子交换容量、加工成膜性能、机械强度以及降解稳定性方面的研究进展,介绍了国内外短侧链全氟磺酸燃料电池膜的研究现状。分析表明侧链长度明显影响全氟磺酸膜的综合性能,短侧链因不含醚键及叔碳原子,赋予磺酸树脂更好的稳定性和持久性,其优异的电导和保湿性能更适合在高温低湿等苛刻条件下应用。提出短侧链全氟磺酸膜未来的研发趋势,包括降低成本、兼顾高电导的同时保持较低的氢气或甲醇透过率、进一步明确传质及降解机理及提高实际运行的综合性能。     

Monoenoic fatty acids in human brain lipids: Isomer identification and distribution

The carbon chain length distribution and the double bond positional isomer composition of the monoenoic fatty acids of the lipids of total human brain tissue have been determined using gas chromatography and gas chromatography/mass spectrometry of the fatty acid methyl and picolinyl esters. The even chain length monoenoic C₁₆ to C₂₈ fatty acids contain predominantly two positional isomer series, the n−7 and n−9cis homologues, whose relative proportion varies significantly with chain length. The odd chain length long-chain fatty acids consist of n−8 and n−10 isomers, whereas the odd chain length very long-chain (more than 22 carbon) fatty acids are n−7 and n−9 isomers.     

Adsorption of alcohols on finely divided powders

The flow micro-calorimeter has been used for the determination of energies of adsorption at monolayer coverage (mcal/g of powder) from solution for a homologous series of long-chain alcohols, the solvent in each case being n-heptane. The results show that the energies increase with increase in length of the carbon chain until the chain has six carbon atoms; the energies then fall to a constant value. The area occupied by one adsorbed molecule increases slowly at first, more rapidly for a chain length of four to eight carbon atoms and then approaches a constant value. The heat of adsorption (kcal/mole of solute adsorbed) rises rapidly at first and smoothes off to a constant value as the length of the carbon chain increases above ten. It is suggested that this indicates that the molecules orientate themselves in the form of a spiral with six carbon atoms on the surface of the solid; this requires a bond angle of 120° which is in agreement with the findings of Calvet & Astruc.     

Hollow Nanostructured Anode Materials for Li-Ion Batteries

Hollow nanostructured anode materials lie at the heart of research relating to Li-ion batteries, which require high capacity, high rate capability, and high safety. The higher capacity and higher rate capability for hollow nanostructured anode materials than that for the bulk counterparts can be attributed to their higher surface area, shorter path length for Li⁺ transport, and more freedom for volume change, which can reduce the overpotential and allow better reaction kinetics at the electrode surface. In this article, we review recent research activities on hollow nanostructured anode materials for Li-ion batteries, including carbon materials, metals, metal oxides, and their hybrid materials. The major goal of this review is to highlight some recent progresses in using these hollow nanomaterials as anode materials to develop Li-ion batteries with high capacity, high rate capability, and excellent cycling stability.     

Some detersive properties of model straight chain sodium alkylbenzenesulfonates

Model long chain sodium ortho and para alkylbenzenesulfonates having primary, secondary and tertiary carbon atoms attached to the phenyl group have been evaluated for foam, wetting and detergency. The data indicate that the surface active properties of these three classes of compounds which are primarily linear in structure are dependent upon sulfonate position, phenyl position and chain length. Each of these factors contributes to performance. Ortho sulfonates are better wetting agents than para sulfonates but the para compounds generally foam better and appear to have superior detergency properties than their respective ortho isomers. Ortho sulfouate in a detergent composition may have a greater influence on surface active properties than had been heretofore recognized. Presented the AOCS Meeting in Houston, Texas, 1965.