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Reverse micro-emulsion dyeing technology shows a high dye uptake and fixation rate, and effectively decreases the amount of waste water in the textile industry. However, the influence of surfactants and co-surfactants on micro-emulsifying water in reverse micro-emulsions has not been investigated. In this study, the micro-emulsifying mechanism in silicone media and the influence of nonionic surfactants and co-surfactants on micro-emulsifying water have been investigated. The results show that a large amount of water can be emulsified using alcohol-polyoxyethylene ethers, especially under 3–5 ethylene oxide groups in molecular structure. As co-surfactant, alcohol which contains 4–9 carbon chains could spontaneously form reverse micro-emulsions in silicone media. The effects of solution pH and ionic strength on the amount of emulsified water were also evaluated. The results show that a large amount of water could be emulsified in silicone media at solution pH 2–9. Meanwhile, the amount of emulsified water decreased with increasing ionic strength. Thus, the optimum conditions for water emulsification are low ionic strength and pH between 2 and 9.

The synthesis and properties of ethoxylated castor oil acid methyl esters (ECAME) were investigated. Ethylene oxide (EO) can react directly with the ester group and hydroxyl group of castor oil acid methyl esters in the presence of an alkaline catalyst. ECAME with different average EO adduct numbers were synthesized and, through testing the degree of EO addition, it was found that only a few EO moieties (2–4) inserted into the hydroxyl group. In addition, the physicochemical properties of ECAME were studied. ECAME can be used as nonionic surfactants with good properties.

BACKGROUND Elucidation of droplet dynamic impact and deposit formation on leaf surfaces would assist in modifying application strategies potentially to improve biological control efficiency and minimize pesticide waste. RESULTS The mechanics of the three-dimensional droplet impact and formation process on hydrophilic and hydrophobic leaf surfaces was investigated with a system that independently controlled droplet diameter, impact speed and impact angle. Spray solutions were made with a nonionic surfactant in distilled water. Water-only droplets rebounded or splashed on hydrophobic leaves of Euphorbia pulcherrima and Zea mays, but not on hydrophilic Dracaena deremensis leaves. Droplet spread areas on D. deremensis at 5.0 m s−1 impact speed increased 1.9-fold when the droplet diameter was increased from 175 to 481 µm. Similarly, spread areas of 306 µm water-only droplets increased 2.0-fold when the impact speed was increased from 3.5 to 7.0 m s−1. At surfactant concentrations of 0, 0.25, 0.50 and 0.75% (v/v), percentages of droplets that either splashed or bounced off Z. mays were 56, 37, 2 and 0% respectively. CONCLUSION Microscopic measurements of droplet impact clarified the effectiveness of surfactants in enhancing droplet retention on hydrophobic leaves and also revealed that water droplets did not rebound or splash on hydrophilic leaves. © 2014 Society of Chemical Industry

The effect of Triton X-114 on the physicochemical properties of a single-chain antibody fragment (scFv) has been studied. According to the far UV circular dichroism spectroscopy, the secondary structure of the recombinant antibody was not significantly affected by the presence of Triton. From the antibody tertiary structure analysis, it was found that the surfactant could be located around the tryptophan molecules accessible to the solvent, diminishing the polarity of its environment but maintaining most of the protein structure integrity. However, in certain conditions of high temperature and high concentration of denaturant molecules, the presence of TX could compromise the antibody fragment stability. These results represent a previous step in designing scFv purification protocols and should be considered prior to developing scFv liquid–liquid extraction procedures Fil: Pellegrini Malpiedi, Luciana. Universidade de Sao Paulo; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Quimicos Rosario. Universidad Nacional de Rosario. Facultad de Cs.bioquímicas y Farmaceuticas. Instituto de Procesos Biotecnológicos y Quimicos Rosario; Argentina Fil: Nerli, Bibiana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Quimicos Rosario. Universidad Nacional de Rosario. Facultad de Cs.bioquímicas y Farmaceuticas. Instituto de Procesos Biotecnológicos y Quimicos Rosario; Argentina Fil: Abdalla, Dulcinéia Saes Parra. Universidade de Sao Paulo; Brasil Fil: Pessoa, Adalberto Jr.. Universidade de Sao Paulo; Brasil

Foam and surface tension behaviors of different ionic/nonionic surfactant solutions along with their different combinations have been investigated. Among different surfactants, sodium dodecyl sulfate showed the highest foamability over other surfactants. Mixed surfactant systems were always found to have higher foamability than the individual surfactant. It was also noticeable that nonionic surfactants show good foamability when they combine with anionic and cationic surfactants. In the case of mixed surfactant systems, nonionic/cationic surfactant mixtures showed lower surface tension than nonionic/anionic surfactant mixture due to a synergistic effect.

Formation of a low-fat oil-in-water (O/W) nanoemulsion enriched with vitamin E using the nonionic surfactant Tween 40 is studied by means of a high-pressure homogenizer. The effect of different process variables of the emulsification process, including pressure, temperature, and concentration of the emulsifying agent, is evaluated. The relation between pressure and the obtained mean droplet diameter is derived and described by an equation which can be taken as a basis of any process design. The droplet size can be decreased by increasing the vitamin E concentration. A higher fat content slightly affects the droplet size distribution and the mean droplet diameter of the nanoemulsion, so it is recommended to use preparations of nanoemulsions with low fat contents enriched with vitamin E for dietary supplement.

The structure of biomembranes was imitated by introducing nonionic surfactant polyoxyethylene (23) dodecylether, cholic acid and endogenic thermostable protein complex (14–65 kDa) into the mobile phase. The influence of concentration of these additives on the retention of the model compounds was studied. The competing interaction of cholic acid and endogenic thermostable protein complex in the lipid bilayer model was revealed on the basis of chromatographic data. The values of efficiency of the chromatographic column regarding solutes were increased by addition of endogenic thermostable protein complex to the mobile phase containing Brij-35 and cholic acid. Copyright © 2011 John Wiley & Sons, Ltd.

The synthesis and analytical properties of 4,4′-bis(antipyrinyl-4-diazoamino) biphenyl (BAPDAB) were described for the first time. A catalytic kinetic method for the determination of silver was proposed. In the presence of Triton X-100 as a solubilizing agent and 2,2′-dipyridyl as an activator, silver has a very strong catalytic effect on oxidative decoloration of BAPDAB by persulfate in acetic add medium. The reaction was followed spectrophotometrically by measuring the decrease of absorbance of BAPDAB at 478 nm and 50 °C. The calibration graphs are of good linearity in the range of 8.0 × 10−10–1.0 × 10−6 mol/L by a fixed time method. The limit of detection is down to 5.0 × 10−10 mol/L. The catalytic reaction is pseudo-first-order with respect to silver, which in real samples was determined with satisfactory results.

The interaction of fluorocarbon containing hydrophobically modified polyelectrolyte (FMPAANa) with two kinds of non-ionic surfactants (hydrogenated and fluorinated) in a semidilute (0.5 wt%) aqueous solution had been studied by rheological measurements. Association behavior was found in both systems. The hydrophobic interaction of FMPAANa with fluorinated surfactant (FC171) is much stronger than that with hydrogenated surfactant (NP7.5) at low surfactant concentrations. The interaction is strengthened by surfactants being added for the density of active junctions increased. Whereas distinct phenomena for FC171 and NP7.5 start to be found as the surfactants added over their respective certain concentration. The interaction of polyelectrolyte with fluorinated surfactant increases dramatically while that with hydrogenated surfactant decreases.

One complicated silicic acid system, containing Al 3+ , Mg 2+ , Fe 2+ , and Fe 3+ , is prepared through acidolysis of blast furnace slag. By investigating its gel time concerned with pH value, compared with that of ordinary silicic acid system, it is shown condensation reaction existing and efficiently controlling gelling characteristics of complicated silicic acid system by regulating pH values. The results are validated by FT-IR spectra analysis. With nonionic surfactant employed, the gel time is increased from 11 to 312 h. more suitable to control gel time than anionic surfactant.

Upon dilution by the petroleum reservoir connate water, the anionic commercial surfactant blend often used in enhanced oil recovery by low tension, becomes more lipophilic at the interface because of so-called selective partitioning. Hence, the optimum formulation is not maintained when the injected slug moves through the reservoir. An opposite variation is found for ethoxylated nonionic surfactant systems. As a consequence of these antagonistic influences, the optimum formulation shift produced by dilution may be eliminated by using an appropriate mixture of anionic and nonionic commercial surfactants, so that the two effects exactly cancel out.

Received 1 February 2008; accepted 4 September 2008DOI 10.1002/app.29280Published online 18 November 2008 in Wiley InterScience (www.interscience.wiley.com).ABSTRACT: In this work, polymer films of low densitypolyethylene and ethylene-vinyl acetate copolymers con-taining two types of antifog additives (nonionic surfac-tants) were exposed to two simulated horticulturalgreenhouse environments, reproducing hot and cold cli-mate conditions. The evolution of the antifog effect wasvisually observed and that of the additive concentrationmeasured using Fourier transform infrared spectroscopy(FTIR). All the films studied showed good antifog proper-ties, but in all cases, the duration of the antifog effect waslonger in the hot-climate test. From the FTIR, we can con-clude that the additives studied showed a low migrationrate and, therefore, when the antifog effect is lost, impor-tant quantities of the additive remain in the bulk.

Copolymers of linear low-density polyethylene (LLDPE) grafted with two novel nonionic surfactants, acrylic glycerol monostearate ester (AGMS) and acrylic polyoxyethylenesorbitan monooleate ester (ATWEEN80), containing hydrophilic and hydrophobic groups and 1-olefin double bond were prepared by using a plasticorder at 190°C. To evaluate the grafting degree, two different approaches based on 1H-NMR data were proposed, and FTIR calibration was showed to validate these methods. The rheological response of the molten polymers, determined under dynamic shear flow at small-amplitude oscillations, indicated that crosslinking formation of the chains could be decreased with increasing the monomer concentration. Their thermal behavior was studied by DSC and polarization microscope (PLM): The crystallization temperature (TC) of grafted LLDPE shifted to higher temperature compared with neat LLDPE because the grafted chains acted as nucleating agents. Water and glycerol were used to calculate the surface free energy of grafted LLDPE films. The results indicated that the novel polyoxyethylene surfactant ATWEEN80 could greatly improve the hydrophilicity of LLDPE and the surface free energy varied from 33 mN/m of neat LLDPE to 106 mN/m of the grafted LLDPE film.

Given the huge dependence on dipolar, aprotic solvents such as DMF, DMSO, DMAc, and NMP in nucleophilic aromatic substitution reactions (SNAr), a simple and environmentally friendly alternative is reported. Use of a "benign-by-design" nonionic surfactant, TPGS-750-M, in water enables nitrogen, oxygen, and sulfur nucleophiles to participate in SNAr reactions. Aromatic and heteroaromatic substrates readily participate in this micellar catalysis, which takes place at or near ambient temperatures.

We investigate the behavior of fluorescing single-walled carbon nanotubes (SWCNTs) under dielectrophoretic conditions and demonstrate their collection with fluorescence microscopy. SWCNTs are dispersed in water with the aid of a nonionic surfactant, Triton X-100, and labeled through noncovalent binding with the dye 3,3'-dihexyloxacarbocyanine iodide (diOC(6)). The chromophore's affinity to the SWCNTs is due to pi-stacking interactions. Carbon nanotube (CNT) localization is clearly identified on the fluorescence images, showing that the nanotubes concentrate between the electrodes and align along the electric field lines.

The nonionic surfactant Triton X-100, which self-assembles in water to form micelles, proves to enhance the title reaction remarkably.

An artificial neural network (ANN) model has been developed for tensammetric determination of a series of Brijes (Brij 30, Brij 35, Brij 56, Brij 96) as nonionic surfactants. The tensammetric method is based on the measurement of the capacitive current of the mercury electrode after adsorption of surfactants. All Brijes were analyzed in the concentration range of 1.0–100.0 μg mL−1. The proposed method shows good sensitivity and applicability to the simultaneous determination of mixtures of four Brijes in aqueous solutions.

The foaming properties of anionic surfactant solutions containing a nonionic surfactant, fatty acid N-methyl-ethanolamide (NMEA), were investigated. Foamability, which is the foam-generating power at the initial stage of foaming, was measured by a laboratory-built foam-testing apparatus, and also by the conventional Ross-Miles test NMEA synergistically increased the foamability of anionic surfactant solutions, particularly when small amounts of NMEA were added. Shorter hydrocarbon chain lengths of NMEA, such as N-octanoyl-N-methylethanol (NMEA-08) and N-decanoyl-N-methylethanol (NMEA-10), showed better performance in the laboratory-built foam tester. The results of the Ross-Miles evaluation, however, were completely opposite. Compared with commercial nonionic boosters, such as fatty acid monoethanolamide, fatty acid diethanolamide, and lauramidopropyldimethylbetaine (LPB), NMEA was the most effective for increasing foamability of the solution at the initial stage. The most popular amphoteric foam booster, LPB, did not increase foamability but likely generated the initial foam volume on the Ross-Miles test as a result of foam film stabilization. From these results, a foam-boosting mechanism of NMEA different from that of LPB is suggested.

The phase behaviour at 25 °C of surfactant-oil-water systems containing pine oil and commercial ethoxylated isotridecanols (nonionic surfactants) is reported. All Winsor phase behaviour types were observed, depending on the surfactant average Ethylene Oxide Number and concentration. The technique used was based on the occurrence of the so-called optimum formulation at which a bicontinuous microemulsion phase is in equilibrium with excess water and oil, with an associated minimum in interfacial tension. Optimum formulation was found at a zero value of the hydrophilic- lipophilic deviation (HLD), a numerical expression which takes all formulation variables into account. This HLD relationship was used to determine the Equivalent Alkane Carbon Number (EACN) of pine oil and its major components. # 2003 Society of Chemical Industry

Dissolution in water of pure liquid nonionic surfactants and some of their mixtures was studied in previous research in this laboratory. In the work described here, a hanging drop slide was used to study disintegration behavior in water of corresponding granules consisting of many zeolite particles bound together with a liquid nonionic surfactant. Granules disintegrated below the cloud point of the nonionic surfactant or mixture. Few differences in disintegration time were seen for various systems. However, disintegration did not occur when the neat surfactant developed viscous myelinic figures upon contact with water. Nor was it observed when a dilute aqueous phase coexisted with a surfactant-rich L1 phase or L3 (sponge) phase at equilibrium.

We prepared a new nonionic surfactant, 8, in which the n-dodecyl chain is attached at the C-3 carbon of the D-glucose-based glucopyranose moiety by the linkage Z=−O-(α-PP-O)n with −O-(α-PP-O)n being a commercial poly-(α-propyloxy) oligomeric mixture (with average n=6). This amphiphilic behavior study showed that, when compared to the reference compound 3-O-dodecyl-D-glucopyranose (Z=O), compound 8 exhibits (i) a water solubility that is 100-fold higher, (ii) a hydrophilic-lipophilic balance value increase from 8.5 to 12.6 units, and (iii) a slighly lower critical micelle concentration.

A reverse micellar system in supercritical carbon dioxide has been developed as a dyeing medium. Water-soluble dyes such as reactive dyes and acid dyes could be sufficiently solubilised in the interior of a specially constituted reverse micelle. Protein fabrics, silk and wool, were satisfactorily dyed even in deep shades with conventional acid dyes without any special pretreatment. Cotton cellulose fabric was also dyed with conventional reactive dyes when the electrostatic force of repulsion between dye and cotton was eliminated. Compared to previously proposed supercritical dyeing methods, dyeing of fabrics with this system could be performed at low temperatures and pressures in a short time.

The effect of different alkyl chains of anionic surfactants on properties of binary anionic-nonionic mixed surfactant systems was studied. These systems included ocytldodecyl-, and cetylsulfoacetates mixed with isooctyl phenol nonyl ethoxylate. The critical micelle concentration of mixed surfactants shifted to lower values compared to those of the single anionic surfactants. Effectiveness values increased with decreases in the mole fraction of anionic surfactants. The negative values of interaction parameter (β) increased with increases in the chain length of anionic surfactants.

The feasibility of wool fabrics pretreated with a chitosan/nonionic surfactant mixture and dyed with reactive dyes was studied. The results showed that the presence of the chitosan/surfactant improved the application to wool, which greatly enhanced the color strength when dyed at 50°C but little change was observed when dyed at 80°C. The higher the concentration of chitosan/surfactant added, the greater was the color strength of the dyed wool fabrics. The amounts found to be optimum for dyeing were 0.5% chitosan and 1.0% surfactant. The washing fastness of the dyed wool fabrics was in the range of grades 4–5, the dry rubbing fastness was in the range of grades 4–5, and the wet rubbing fastness was in the range of grades 3–4. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2859–2864, 2001

The foaming properties of bovine serum albumin (BSA), in the absence and presence of Triton X-100 (TX-100), have been investigated using shaking tests. The results showed that increases in the TX-100 bulk concentration rapidly reduced both foam height and foam stability at TX-100 concentrations below about 0.25 mM, but increased foam height and foam stability at TX-100 concentration above 0.3 mM. The interaction between BSA and TX-100 has been studied using fluorescence spectroscopy. The surfactant appeared to bind to BSA with a low molar ratio (about one surfactant molecule per protein molecule) at concentrations below the critical micelle concentration (CMC); the binding became weaker at concentrations above the CMC. It was confirmed that protein-protein or protein-surfactant interactions had significant influence upon foaming properties of mixed protein/surfactant system.

Acohol ethoxylate (AE) is the most widely usednonionic surfactant in householddetergents. Herewe present compound-specific bioconcentration data for AE constituents determined in flow-through experiments. Values of the bioconcentration factor (BCF) and the rate constants of uptake (k1) and elimination (k2) in fathead minnows (Pimephales promelas) ranged between

The decrease in the equilibrium sorption of Pb(II) and nonionic surfactants (oxyethylated alcohols OS-20 and alkylmonoethers ALM-10) in H-form of Purolite C 106 cation exchanger was observed due to their presence in the same solution. The sorption of Pb(II) both in the form of free cations and in the form of Pb(II) bonded with surfactant takes place. The sorption of Pb(II) bonded with OS-20 is higher compared with that of Pb(II) bonded with ALM-10. In the presence of ALM-10 the sorption of Pb(II) free cations prevails. Increasing the acidity from pH 5 to 3, increases the rate of the sorption of surfactant. Due to the presence of surfactant the rate of Pb(II) sorption also increases, while without surfactant it decreases with an increase in acidity.

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.

The tensammetric determination of the total concentration of mixtures of nonionic and anionic surfactants is desribed. By taking advantage of the different accumulation behavior of nonionic and anionic surfactants on the surface of the hanging mercury drop electrode (HMDE), it has been possible to determine the total concentration of nonionic surfactants without contribution from anionic surfactants. After subtraction of nonionic surfactant concentration from total, the concentration of anionic surfactants can be determined indirectly. Detection limits of 10 to 100 μg L−1 for single compounds and 100 μg L−1 for mixtures were calculated. Humic acids, relevant complexing reagents (like EDTA) and different cations do not interfere in the determination when they are present in typical concentrations found in surface waters. The method has been applied to several mixtures of surfactants. The possibility of solid-phase-extraction (SPE) for sample pretreatment has been investigated.

Chitosan application to wool is known to be associated with problems such as its weak binding and uneven distribution. In an attempt to overcome such problems, chitosan was applied from a mixture with a nonionic surfactant. A weak time interaction was observed between chitosan and the surfactant over time, resulting in changes in the conformation of chitosan in solution, which was confirmed by viscosity measurements. The presence of chitosan/surfactant association improved the application to wool, which was assessed by dyeing the treated wool with a reactive dye at 60 degrees C. Since this technique offers the possibility of producing deeper and more vivid colours without increasing the concentration of dye used, dyeing was also carried out at 95 degrees C, closer to practical dyeing conditions. An improvement in the fixation of the reactive dye was observed.

The detergency effect has been examined for a series of technical nonionic surfactants with the use of statistical experimental designs and revealed a plateau in each of the response surfaces obtained. The surfactant concentrations and washing temperatures, needed to reach the edge of each detergency effect plateau, were also determined. These conditions, which define the edge of the plateau, could be well modeled from the physicochemical properties of the surfactants with the use of partial least squares of latent structures. It was also possible to point out the importance of the different physicochemical properties. If an experimental design has been utilized, the detergency effect of a nonionic surfactant can be modeled from multiple linear regression as a function of surfactant concentration, washing time, and washing temperature. We have shown how these regression coefficients can be modeled from the physicochemical properties of the surfactants. Partial least squares of latent structures were used to estimate these models as well. We also demonstrated how these models can be used to predict the regression coefficients of a surfactant not included in the model estimations. The resultant regression coefficients can then be used to predict the detergency effects of this surfactant at different variable settings. The detergency effects thus obtained are in good agreement with measured data acquired under corresponding conditions.

The effects of a nonionic surfactant (C{sub 14-15} AE-7) on survival and growth of juvenile bluegill sunfish and on survival and reproduction of fathead minnows were investigated in the laboratory and in outdoor stream mesocosms. In the laboratory, where the fish were exposed for 10 d, the 96-h LC50 values for bluegill sunfish and fathead minnows were 650 and 770 {micro}g/L, respectively. The no-observed-effect concentration (NOEC) for survival and swimming performance of bluegill sunfish and for survival of fathead minnows was 160 {micro}g/L. The lowest-observed-effect concentration (LOEC) for these toxic responses was 460 {micro}g/L. In the stream mesocosms, where the fish were exposed for 30 d, the NOEC for bluegill sunfish and growth was >330 {micro}g/L. The LOEC for fathead minnow survival was 330 {micro}g/L, and the NOEC was 280 {micro}g/L. Decreased egg laying by fathead minnows was noted in the streams at concentrations of 330 {micro}g/L or greater. Close correspondence between the results of laboratory tests and those obtained under field conditions in the mesocosms indicates that for this surfactant, it may not be necessary to apply ``safety factors`` to extrapolate results from the laboratory to the field.