磺酸型双子表面活性剂与十二烷基硫酸钠的复配研究

通过微波方法合成了乙二醇双琥珀酸2-乙基己酯磺酸钠(Gemini-7),研究了其与十二烷基硫酸钠(SDS)复配体系的稳定性、表面张力、泡沫性能、乳化性能、增溶性能等。结果表明,Gemini-7与SDS有很好的复配性,在SDS溶液中加入少量的Gemini-7后表面张力比单一组分的表面张力低。SDS/Gemini-7体系的泡沫性能、乳化性能和增溶性能与SDS单一体系相比都有显著的提高。因此在含有SDS的产品中加入少量的Gemini-7,可提高其使用效率。     

十二烷基硫酸钠与铝盐絮凝特征研究

为了更好地去除水体中残留的表面活性剂,选用十二烷基硫酸钠为研究对象,在298．15K时,对临界胶束浓度之上和CMC之下的SDS溶液与典型无机絮凝剂（AlCl3）的絮凝行为进行了实验和理论方面的研究。结果表明：在SDS／AlCl3絮凝体系中,0．01mol／LSDS和0．001mol／LSDS与铝盐达到最佳絮凝时,Al^3＋与SDS的摩尔比（记为CAl／BSDS）分别约为0．5和1．0。最佳絮凝时,体系Zeta电位接近零点,表面张力降到最小,pH值均在4．0以下,电导率随CAl／BSDS呈线性增大变化。在0．01mol／LSDS与Al“絮凝体系中,当凝聚摩尔比G化赫约为21．6时,絮凝体完全消失并不再浑浊,而在0．001mol／LSDS与Al^3＋絮凝体系中观察不到絮凝体完全消失的现象。     

十二烷基硫酸钠/聚乳酸复合材料性能研究

主要研究了聚乳酸（PLA）与十二烷基硫酸钠（SDS）复合材料的制备,以及SDS/PLA复合材料亲水性和降解过程当中pH值的改变程度。采用溶解成膜法制备SDS/PLA复合材料。主要考察了在PLA中加入SDS后形成复合材料后对其亲水性的影响,结果表明,当加入适量的SDS能比较明显地改变其亲水性,让复合材料亲水性提高。对SDS/PLA复合材料进行了降解测试,通过对三种降解体系比较,结果表明,添加了SDS之后的复合材料能够较好地保持聚乳酸原有的力学性能,添加了适量的SDS能够较好地中和聚乳酸降解过程所产生的乳酸,从而使降解体系的pH值保持相对稳定。     

罗丹明B与十二烷基硫酸钠胶团的相互作用

采用荧光光谱法研究了罗丹明B与阴离子表面活性剂十二烷基硫酸钠(SDS)胶团的相互作用以及无机盐的影响。结果表明,罗丹明B作为探针分子可以用来测定表面活性剂SDS在水溶液中的临界胶团浓度。两者之间的相互作用可用缔合常数Ka定量表示,体系中Ka值随着无机盐浓度的增大而增大,表明罗丹明B与SDS胶团的相互作用增大。     

十二烷基硫酸钠对非离子表面活性剂CM101浊点的影响

研究了阴离子表面活性剂十二烷基硫酸钠(SDS)对非离子表面活性剂CM101浊点的影响。结果表明:当SDS加入量为2%时,CM101的浊点提高到59.6℃,达到农药制剂热稳定性的要求。同时,该混合体系满足非理想二元表面活性剂复配增效的条件,表面张力和临界胶束浓度都有明显降低。     

活性炭种类对十二烷基硫酸钠吸附容量的影响

利用亚甲蓝分光光度分析法测定典型市售煤基和木质活性炭对溶液中十二烷基硫酸钠(SDS)的液相吸附等温线,确定活性炭对SDS的吸附容量;采用气体吸附仪表征活性炭的孔结构和比表面积,检测了活性炭样品的碘值及亚甲蓝值;最后关联活性炭吸附性能指标、比表面积与SDS吸附容量之间的关系.结果表明:以长焰煤、无烟煤、褐煤及椰壳为原料制...     

Viscoelastic Behavior of Alkyl Ether Sulfate Systems Containing Sodium Carbonate

Relaxation behaviors in systems containing sodium alkyl ether sulfate and sodium carbonate were studied. The anionic surfactants were commercial grade systems with average chain lengths of twelve carbons and either one, two, or three ethoxy (EO) groups. It was found that viscosity maxima in the three systems were achieved at particular salt levels that increased with an increase in the number of EO groups. Relaxation of the optimized systems was studied by measuring the complex, storage and loss moduli as a function of frequency. Temperature was varied between 5 and 45 °C. While characterization of relaxation in terms of the Maxwell model adequately described data below the threshold of ωτ < 1, the model failed to adequately describe behavior at higher frequencies. A modified expression with an additional Rouse relaxation mode adequately described relaxation throughout the frequency range studied. Temperature dependencies provided estimates of activation energies which were consistent with literature values for reptation modes of relaxation. No temperature dependencies were seen for the second relaxation mode of the model. Studies of ultrasonic attenuation in the surfactant system determined that attenuation increased in systems with higher EO content. Relaxation times were additionally found to decrease with increased EO content. This implied that diffusion in the compressive relaxation modes was more dependent on the sizes of the micellar structures as opposed to the sizes of the individual surfactant molecules.     

十二烷基硫酸钠的纯化

为得到满足表面化学实验研究规格的十二烷基硫酸钠（以下简称ＳＤＳ），用水结晶、泡沫分离、乙醇三次重结晶、乙醚抽提对市售的一种Ｃ．Ｐ．级试剂进行纯化处理。就所得结果对各种纯化方法的特点进行比较、分析和讨论，据此提出了一种纯化市售Ｃ．Ｐ．级试剂的方案，并用于另一种市售Ｃ．Ｐ．级试剂的纯化，获得满意的结果。     

吐温和十二烷基硫酸钠复配修饰制备纳米铜研究

在一定温度的水溶液中,以硫酸铜为前驱体,抗坏皿酸（Vc）为还原剂,加入适量修饰剂,合成粒径和形貌可控的纯铜纳米粒子,并通过XRD射线衍射,扫描探针显微镜等检测手段对产品进行了表征。结果表明,修饰剂的加入对粒径大小、分布、形貌和晶型结构影响显著;制备的纳米铜颗粒为具有立方品型结构的球型颗粒,分散性较好,尺寸较为均匀,约为60～80nm。纳米铜颗粒表面形成了较薄的有机物质包覆层,它有效阻止了纳米铜粉在空气和水中的氧化和团聚,提高了纳米铜颗粒的分散性和稳定性。     

Temperature Comparative Studies on Self-Assembly of Sodium Dodecyl Sulphate and Didodecyl Dimethyl Ammonium Bromide in Aqueous,Brine, and Trifluoroethanol Media

An approach based on experimental and theoretical methods was used to compare the self-assembly [i.e., determination of the critical micelle concentration (CMC), degree of ionization (α) and counterion binding (β)] of sodium dodecyl sulfate (SDS) and didodecyl dimethyl ammonium bromide (DDAB) in deionized water and 10 mM NaCl and 10 (vol) % trifluoroethanol solutions. Experimental methods consisted of electrical conductometry, tensiometry, fluorimetry, and determination of Krafft temperature. A critical analysis of the thermodynamics of self-assembly by the Gibbs–Helmholtz equation and the van't-Hoff rationale provided values of several parameters, such as the change of Gibbs free energy and enthalpy change of micellization ( and , respectively) and the Gibbs free energy of surfactant tail groups (∆G⁰_trans). Interfacial properties, aggregation number (N_agg), micropolarity (I₁/I₃), microviscosity (η), packing parameter (P), dielectric constant (D), anisotropy (r), and Stern–Volmer binding constant (K_SV) for SDS and DDAB in different temperatures and different systems were determined.     

古尔伯特十六醇硫酸钠的合成与性能研究

以合成的古尔伯特十六醇(2-己基-癸醇)为原料,通过SO3硫酸化法合成了相应的古尔伯特十六醇硫酸钠(C16GS),提纯后活性物含量可达96.8%。最后对古尔伯特十六醇硫酸钠(C16GS)与十二烷基硫酸钠(SDS)的性能进行了对比研究,发现C16GS表面活性、润湿性能、乳化性能均强于SDS,发泡性能与SDS相似但泡沫稳定性差。与AEO9的复配显示,C16GS和AEO9复配溶液在对碳黑污布的去污中产生了协同作用。     

Phase Behavior of Sodium Dodecyl Sulfate-n-Butanol-Kerosene-Water Microemulsion System

Experiments were carried out to investigate the influences of cation from electrolytes and acidity/alkalinity on the phase behavior of sodium dodecyl sulfate-n-butanol-organics-water （with electrolytes） microemulsion sys-tem. The organics used is commercial kerosene. The volume ratio of water to organics is 1︰1. The results show that the type and valence of electrolyte cations are important factors influencing the microemulsion behavior. Biva-lent Ca2＋is more effective than monovalent K＋and Na＋for the formation of Winsor type III and II microemulsion. For electrolytes with the same monovalent cation Na＋, i.e. NaCl and Na2CO3, anions in the electrolyte have some effect. Bivalent anion 23CO - leads to a lower activity of cation Na＋than monovalent anion Cl-. NaOH （or KOH） behaves similar with NaCl （or KCl）. When HCl is used as electrolyte, its acidity plays an important role. Phase in-version of microemulsion from type III （or II） to type I is observed through precipitation of Ca2＋using Na2CO3, neutralization of HCl by NaOH, and addition of water to the system, which releases the oil from the microemulsion.     

Characterization and Properties of Recycled Polypropylene/Coconut Shell Powder Composites: Effect of Sodium Dodecyl Sulfate Modification

This research work focuses on the utilization of coconut shell powder (CSP) as filler in recycled polypropylene (rPP). Sodium Dedecyl Sulfate (SDS) was used as coupling agent in these composites. The effect of filler content and SDS on tensile properties, thermal properties, water absorption and morphology of rPP/CSP composites were investigated. In this study, modified rPP/CSP composites with SDS show significant increased tensile propertied, thermal stability, crystallinity and low water absorption compared unmodified rPP/CSP composites. Those improvements were contributed by the coupling effect of SDS.     

分子动力学模拟研究盐离子对十二烷基硫酸钠胶束溶液中亲水亲油协调机制的影响

The presence of salt has a profound effect on the size, shape and structure of sodium dodecyl sulfate (SDS) micelles. There have been a great number of experiments on SDS micelles in the presence and absence of salt to study this complex problem. Unfortunately, it is not clear yet how electrolyte ions influence the structure of micelles. By describing the compromise between dominant mechanisms, a simplified atomic model of SDS in presence of salt has been developed and the molecular dynamics (MD) simulations of two series of systems with different concentrations of salt and charges of ion have been performed. Polydispersity of micelle size is founded at relatively high concentration of SDS and low charge of cation. Although the counter-ion pairs with head groups are formed, the transition of micelle shape is not observed because the charge of cation is not enough to neutralize the polar of micelle surface.     

The Properties of Lauric Acid and Their Significance in Coconut Oil

The primary fatty acid of coconut oil is lauric acid, which is present at approximately 45–53 %. The metabolic and physiological properties of lauric acid account for many of the properties of coconut oil. Coconut oil is rapidly metabolized because it is easily absorbed and lauric acid is easily transported. Detailed studies have shown that the majority of ingested lauric acid is transported directly to the liver where it is directly converted to energy and other metabolites rather than being stored as fat. Such metabolites include ketone bodies, which can be used by extrahepatic tissues, such as the brain and heart, as an immediate form of energy. Studies on the effect of lauric acid on serum cholesterol are contradictory. Among saturated fatty acids, lauric acid has been shown to contribute the least to fat accumulation. Lauric acid and monolaurin have demonstrably significant antimicrobial activity against gram positive bacteria and a number of fungi and viruses. Today there are many commercial products that use lauric acid and monolaurin as antimicrobial agents. Because of the significant differences in the properties of lauric acid relative to longer chain fatty acids, they are typically differentiated as medium‐chain fatty acids covering C6–C12, and long‐chain fatty acids covering C14 and longer.     

Biolytic Effect of Rhamnolipid Biosurfactant and Dodecyl Sulfate Against Phagotrophic Alga <Emphasis Type="Italic">Ochromonas danica</Emphasis>

Surfactants can affect biological activities and pose serious threats to the aquatic ecosystem if discharged without proper treatment. Rhamnolipid is a biosurfactant with promising agricultural, industrial and biomedical applications. It is important to assess the risks posed by rhamnolipid before it is adopted for large scale use. In this study, toxicity of rhamnolipid was estimated with the effects of motility loss, membrane permeability, and cell lysis using a phagotrophic alga Ochromonas danica. O. danica is a sensitive algal species without a protective cell wall and it represents a group of phagotrophic flagellates ecologically important in the aquatic ecosystem. A common synthetic surfactant, sodium dodecyl sulfate (SDS), was used for comparison. Results suggested that rhamnolipid is significantly less biolytic than SDS and the effects required longer exposure. Lysis of O. danica cells by rhamnolipid was serious only at concentrations over its critical micelle concentration. Motility loss was, however, significantly more sensitive; about 75% loss after 20 min exposure to 50 mg/L rhamnolipid.     

Inactivation and Unfolding of the Hyperthermophilic Inorganic Pyrophosphatase from Thermus thermophilus by Sodium Dodecyl Sulfate

Inorganic pyrophosphatase (PPase, EC 3.6.1.1) is an essential constitutive enzyme for energy metabolism and clearance of excess pyrophosphate. In this research, we investigated the sodium dodecyl sulfate (SDS)-induced inactivation and unfolding of PPase from Thermus thermophilus (T-PPase), a hyperthermophilic enzyme. The results indicated that like many other mesophilic enzymes, T-PPase could be fully inactivated at a low SDS concentration of 2 mM. Using an enzyme activity assay, SDS was shown to act as a mixed type reversible inhibitor, suggesting T-PPase contained specific SDS binding sites. At high SDS concentrations, T-PPase was denatured via a two-state process without the accumulation of any intermediate, as revealed by far-UV CD and intrinsic fluorescence. A comparison of the inactivation and unfolding data suggested that the inhibition might be caused by the specific binding of the SDS molecules to the enzyme, while the unfolding might be caused by the cooperative non-specific binding of SDS to T-PPase. The possible molecular mechanisms underlying the mixed type inhibition by SDS was proposed to be caused by the local conformational changes or altered charge distributions.     

Removal of Hexavalent Chromium from Aqueous Solutions by Sodium Dodecyl Sulfate Stabilized Nano Zero-Valent Iron: A Kinetics,Equilibrium, Thermodynamics Study

Sodium dodecyl sulfate stable nanoscale zero-valent iron (SDS-nZVI) was synthesized by the sodium borohydride reduction method, characterized with SEM and XRD. SDS-nZVI was used for the removal of Cr (VI) from aqueous solutions at different conditions in a batch process. XRD analysis indicated the presence of iron oxide and iron-chromium hydroxide coprecipitation on the surface of SDS-nZVI after reaction some time. The reaction kinetics, mechanism, isotherms, and thermodynamics for Cr (VI) removal of aqueous solution via SDS-nZVI were investigated. The pseudo-second-order model was relatively suitable for describing the reaction process. Intraparticle diffusion model was used to analysis the mechanism, the results indicated that there were two processes (bulk diffusion and surface diffusion) controlling the reaction rate, while only one was rate limiting in any particular time range. The fitted Temkin and D-R model satisfactorily explanted the experimental data in the range of 303–343 K. The maximum removal capacity of SDS-nZVI for Cr (VI) was obtained for 336.7 mg g^?1 at 303 K. The overall removal process was endothermic. These results demonstrated that SDS-nZVI could potentially be used as an effective material for environmental remediation.     

Effect of Surfactant Impregnation into Chitosan Hydrogel Beads Formed by Sodium Dodecyl Sulfate Gelation for the Removal of Congo Red

The effect of cetyltrimethylammonium bromide (CTAB) and triton X-100 (TX100) impregnation into chitosan hydrogel beads formed by sodium dodecyl sulfate (SDS) gelation (CSB) was investigated for the adsorption of Congo red (CR) from aqueous solutions. An impregnation of CTAB at 0.1 wt% into CSB increased adsorption from 97.46 mg/g to 113.24 mg/g, while 0.5 wt% TX100 impregnation into CSB registered a very small increase from 112.56 mg/g to 115.64 mg/g. CSB/CTAB exhibited similar adsorption at all pH levels (4-9 Gupta , V.K. ; Suhas , X. ( 2009 ) Application of low-cost adsorbents for dye removal–A review . J. Environ. Manage. , 90 ( 8 ): 2313 . Blackburn , R.S. ( 2004 ) Natural polysaccharides and their interactions with dye molecules: Applications in effluent treatment . Environ. Sci. Technol. , 38 ( 18 ): 4905 . Guibal , E. ( 2004 ) Interactions of metal ions with chitosan-based sorbents: A review . Sep. Purif. Technol. , 38 ( 1 ): 43 . No , H.K. ; Kim , S.D. ( 2006 ) Growth of soybean sprouts affected by chitosans prepared under various deproteinization and demineralization times . J. Sci. Food Agr. , 86 ( 9 ): 1365 . Ueno , H. ; Mori , T. ; Fujinaga , T. ( 2001 ) Topical formulations and wound healing applications of chitosan . Adv. Drug Deliver Rev. , 52 ( 2 ): 105 . Chatterjee , S. ; Lee , D.S. ; Lee , M.W. ; Woo , S.H. ( 2009 ) Enhanced adsorption of congo red from aqueous solutions by chitosan hydrogel beads impregnated with cetyl trimethyl ammonium bromide . Bioresource Technol. , 100 ( 11 ): 2803 . ), but CSB and CSB/TX100 showed lower adsorption at higher pH values. The Sips isotherm model was the best fit for all bead varieties, and the Sips maximum adsorption capacity value of CSB/CTAB (271.74 mg/g) was higher than that for CSB/TX100 (242.72 mg/g) or CSB without surfactant impregnation (174.83 mg/g). The experimental kinetic values of all varieties of beads for CR adsorption followed a pseudo-first-order rate model better than a pseudo-second-order rate model.     

十二烷基硫酸钠的临界胶束浓度的测定及影响分析

临界胶束浓度(CMC)是表面活性剂活性的度量。采用电导法测定表面活性剂十二烷基硫酸钠的临界胶束浓度,并探讨了温度、NaCl或乙醇等对临界胶束浓度的影响。随着温度的升高,CMC增大;NaCl的加入量增大时,CMC在较低浓度下增大,在0.2~0.8 mmol/L范围内CMC随NaCl的量增大而降低;乙醇的加入量随体积比从0%~2.5%增大时,CMC增大,并分析了SDS的CMC发生变化的原因。