Sodium Dodecyl Benzene Sulfonate Concentration Research Articles

Microstructure transformation of PDMS-E grafted gelatin polymers induced by SDS and SDBS

Inorganic–organic hybrid materials with tunable chemical and physical properties were prepared from mono epoxy terminated polydimethylsiloxane (PDMS) macromonomer and gelatin for improving their flexibility and hydrophobicity. Sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS) were used to enhance the compatibility of two polymers phases. Measurement of grafting density indicated that anionic surfactants played a crucial role in deciding the detailed microstructure of PDMS-E grafted gelatin (PGG) polymers in alkaline solution. The interaction between gelatin and SDS/SDBS was investigated by viscosity and SEM. Viscosity analysis showed a regular increase in SDS system and a steeper change in the case of SDBS. SEM micrographs displayed a series of structural transitions (spherical, spindle, irregular granular and spherical aggregates) with the increase of SDS concentration, but spindle and granular aggregates appeared alternately as varying SDBS concentrations. The results demonstrated that both the electrostatic and hydrophobic interactions between anionic surfactant and gelatin controlled the aggregate structure of gelatin–SDS/SDBS, which affected the compatibility between gelatin and PDMS. Thermal properties of PGG polymers had changed with the modification of polymer microstructure. The results above revealed that microstructure transformation of PGG polymers was determined by the compatibility of two polymers in anionic surfactant aqueous solution and the chemical nature of their monomers.

N-Type Thermoelectric Performance of Functionalized Carbon Nanotube-Filled Polymer Composites

Carbon nanotubes (CNTs) were functionalized with polyethyleneimine (PEI) and made into composites with polyvinyl acetate (PVAc). CNTs were dispersed with different amounts of sodium dodecylbenzenesulfonate (SDBS) prior to the PEI functionalization. The resulting samples exhibit air-stable n-type characteristics with electrical conductivities as great as 1500 S/m and thermopowers as large as −100 µV/K. Electrical conductivity and thermopower were strongly affected by CNT dispersion, improving the properties with better dispersion with high concentrations of SDBS. This improvement is believed to be due to the increase in the number of tubes that are evenly coated with PEI in a better-dispersed sample. Increasing the amount of PEI relative to the other constituents positively affects thermopower but not conductivity. Air exposure reduces both thermopower and conductivity presumably due to oxygen doping (which makes CNTs p-type), but stable values were reached within seven days following sample fabrication.

Optimization of the Experimental Variables Influencing the Corrosion Rate of Aluminum Using Response Surface Methodology

The effects of temperature and sodium dodecyl benzene sulfonate (SDBS) concentration in hydrochloric acid (HCl) solution on aluminum corrosion rate were investigated using the response surface methodology (RSM) with central composite design (CCD). Optimization studies are an essential tool used in the corrosion systems. RSM is a statistical technique frequently used in most studies involving optimization. RSM was used to optimize the corrosion current density (icorr) of aluminum determined using the potentiodynamic polarization method and to evaluate the effects and the interactions of temperature and SDBS concentration. The lowest icorr was found as SDBS concentration at 130 mg/L and temperature at 24°C. This methodology was first applied successfully in optimizing the conditions that are needed to attain the minimum icorr of aluminum under tested conditions in this study.

Effect of sodium dodecyl benzene sulfonate on the absorption spectrum and determination of crystal violet in aqueous solution

Abstract The effect of sodium dodecyl benzene sulfonate (SDBS) on the absorption spectrum of crystal violet (CV) in an aqueous solution was studied by spectrophotometry. The results showed that when the SDBS concentration was lower than the critical micelle concentration (CMC), the absorption spectrum of CV was altered significantly. However, the effect was eliminated when the SDBS concentration was higher than the CMC, and the absorption maximum of the solution gradually reached that of a SDBS-free CV solution. A new method was thus proposed for the determination of the CV concentration in an aqueous solution containing an anionic surfactant. Under the optimal conditions, i.e., a detection wavelength of 584 nm, a SDBS concentration of 4.8 mmol L−1 and a reaction time of 1 h, the linear range of the method was 0.16 × 10−2 mmol L−1–1.6 mmol L−1.

Coaxial electrospinning with sodium dodecylbenzene sulfonate solution for high quality polyacrylonitrile nanofibers

With sodium dodecylbenzene sulfonate (SDBS) solutions in N,N-Dimethylformamide (DMF) as sheath fluids to surround the core polymer solutions, a series of polyacrylonitrile (PAN) nanofibers with fine diameters, narrow diameter distributions, smooth surfaces and uniform structures have been successfully generated. The fiber diameters (D, nm) could be manipulated through adjusting the SDBS concentration in the sheath fluid (C, mgml−1) with a scaling law of D=790C−0.41 (R2=0.9903) within a range of 5–50mgml−1. The mechanism of sheath SDBS solutions on the evaporation of DMF and the solidification of core polymer jets is discussed. The replacement of SDBS solutions for traditional atmosphere in single fluid electrospinning can lend itself to smoothen the electrospinning process through adjusting the core solvent evaporation rate. It is concluded that coaxial electrospinning with an ion surfactant solution comprises a facile process for producing high quality polymer nanofibers.

Assisted activated carbon‐microwave degradation of the sodium dodecyl benzene sulfonate by nano‐ or micro‐Fe3O4 and comparison of their catalytic activity

An improved method of the integration of activated carbon‐microwave (AC/MW) system with magnetic material such as nano‐ or micro‐Fe3O4 is proposed. A series of experiments to study the Fe3O4 assisted AC/MW (Fe3O4/AC/MW) degradation of sodium dodecyl benzene sulfonate (SDBS), as a model organic contaminant, was performed. The catalytic activities of nano‐Fe3O4/AC and micro‐Fe3O4/AC under MW irradiation were also compared. Some influence factors like added amount of Fe3O4, MW irradiation time, initial SDBS concentration, solution acidity, and Fe3O4/AC dose on the degradation were assessed in detail. The results showed that the addition of Fe3O4 significantly promoted the AC/MW degradation and nano‐Fe3O4/AC displayed higher catalytic activity under MW irradiation. By comparison, the nano‐Fe3O4/AC/MW process exhibited many advantages including high degradation rate, short irradiation time, low cost, no residual intermediates, and no secondary pollution in application. Thus, it shows to be a promising technology for the destruction of organic contaminants in wastewater treatment applications. © 2011 American Institute of Chemical Engineers Environ Prog, 32: 181‐186, 2013

Electrochemical determination of atropine at multi-wall carbon nanotube electrode based on the enhancement effect of sodium dodecyl benzene sulfonate

Herein, a new electrochemical method was described for the determination of atropine based on the enhancement effect of an anionic surfactant: sodium dodecyl benzene sulfonate (SDBS). In pH 10.5 tetramethyl ammonium hydroxide as supporting electrolyte and in the presence of 0.4 × 10 −4 M SDBS, atropine yields a well-defined and sensitive oxidation peak at the multi-wall carbon nanotube electrode (MWCNTE). Compared with that in the absence of SDBS, the oxidation peak current of atropine remarkably increases in the presence of SDBS. The experimental parameters, such as supporting electrolyte, concentration of SDBS, and accumulation time, were optimized for atropine determination. The oxidation peak current is proportional to the concentration of atropine over the range from 3.98 ng/ml to 27.23 ng/ml. The detection limit is 0.449 ng/ml after 2 min of accumulation. This new voltammetric method was successfully used to determine atropine in Indian traditional medicine (seeds and leaves of Datura stramonium) with satisfactory recoveries. The developed method was also used for the analysis of atropine in pharmaceutical formulation of ophthalmic solution (eye drop). The relative standard deviations of intraday and interday analyses for atropine were 0.67% and 0.86% respectively ( n = 3) for the accumulation time of 120 s.

Properties of Canola Protein‐based Plastics and Protein Isolates Modified Using SDS and SDBS

AbstractCanola protein isolates were prepared from canola meal flour using alkaline solubilization and acid precipitation. The isolates were treated with sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS) with concentrations between 1 and 5%. Functional property analysis of modified isolates revealed that water absorption and fat absorption increased by up to 115 and 78%, respectively, with increasing SDBS concentrations. Fat absorption of SDS‐modified isolates showed a similar trend to that of SDBS‐modified isolates (86% increase), but water absorption decreased (by 77%) in the 5% SDS treatment. SDS and SDBS treatments reduced the emulsifying activity of protein isolates by 34 and 30%, respectively. The denaturation effect of SDS and SDBS treatments increased the surface hydrophobicity of proteins and resulted in increased tensile strength (by 14 and 41%), tensile modulus (by 31 and 52%), and toughness (by 44 and 64%) of plastic specimens prepared using modified isolates. Only the 3% treatments of SDS and SDBS increased the elongation of plastics (by 22 and 11%, respectively) while other treatments did not show significant differences from the plastics that used non‐modified isolates. The water absorption of plastics increased by 33% with the 5% SDS treatment; the SDBS treatments showed a 9% decrease in water absorption for the 1% treatment but no significant differences at higher concentrations. Denaturation by SDS and SDBS can be employed to alter functional properties of canola protein isolates as well as the mechanical properties of canola protein‐based plastics.

<b>Investigation of 1-alkanols in organised solutions</b>

Conductometric behaviour of 1-alkanols (C5-C10) in organised solutions of sodium dodecylbenzenesulfonate (SDBS) is investigated. Interaction of each alkanol with anionic surfactant is reflected in terms of association constants, Kc. It is observed that self-assembly of SDBS is induced by the alkanol addition. The depression in critical micelle concentration (CMC) of SDBS caused by each alkanol is translated to partition coefficient, Kc by using interaction coefficient. The dimensionless partition coefficient, Kx is utilized to highlight the energy efficiency of the solubilization process. The results indicate that even longer chain alkanols prefer interfacial area for their residence. The relative solubility of each alkanol is enhanced with increasing SDBS concentration. Such basic information could be vital for development of nano-scale assemblies for specific delivery of water soluble drugs.KEY WORDS: SDBS, Alcohols, Partition coefficient, Relative solubility, Conductometry Bull. Chem. Soc. Ethiop. 2011, 25(3), 469-474.

Synthesis, transformation to octahedron‐like crystals, and gas‐sensing property of six‐horned nanospheres of Cu2O

AbstractSingle‐crystal six‐horned nanospheres of Cu2O with a diameter of 760 nm in average were prepared in aqueous solution of CuCl2and NaOH by using ascorbic acid as the reductant in the presence of sodium dodecyl benzenesulfonate (SDBS) at room temperature. The horn grows along the <100> direction, which is consistent with the protuberant direction of an apex of octahedron. The formation process of six‐horned nanospheres included two steps: the formation of Cu2O nanospheres via Ostwald ripening process, and the appearance of horns on the surface of nanospheres under low concentration of SDBS. As increasing the concentration of SDBS, the six‐horned nanospheres could be transformed into octahedron‐like Cu2O. And at the same concentration of SDBS, keeping the volume ratio of water and ethanol in mixed solutions as 1:1, Cu2O octahedra were obtained. Moreover, gas‐sensing property showed that six‐horned nanospheres of Cu2O had higher sensitivity compared with Cu2O nanospheres and Cu2O octahedra to ethanol gas (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Poly-glutamic acid modified carbon nanotube-doped carbon paste electrode for sensitive detection of L-tryptophan

A novel poly-glutamic acid (PGA) film modified carbon paste electrode (CPE) incorporating carbon nanotubes (CNTs) was first prepared for the determination of l-tryptophan ( l-Trp). Scanning electron microscopy and Fourier transform infrared spectroscopy were applied for characterization of the surface morphology of the modified electrodes and cyclic voltammetry was used to investigate the electrochemical properties of the proposed electrode towards the oxidation of l-Trp. Optimization of the experimental parameters was performed with regard to pH, ratio of CNTs, concentration of glutamic acid, electro-polymerization cycles, accumulation time and concentration of sodium dodecylbenzene sulfonate. The linearity between the oxidation peak current and the l-Trp concentration was obtained in the range of 5.0 × 10 − 8 to 1.0 × 10 − 4 M with a detection limit of 1.0 × 10 − 8 M ( S/ N = 3) and the sensitivity was calculated to be 1143.79 μA∙mM − 1 ∙ cm − 2 . In addition, the PGA modified CPE incorporating CNTs displayed high selectivity, good stability and reproducibility, making it suitable for the routine analysis of l-Trp in clinical use.

Degradation of surfactant wastewater under microwave irradiation in the presence of activated carbon assisted with nano-sized TiO2 or nano-sized ZnO

An improved method treating surfactant wastewater by the addition of semiconductor material such as nano-sized TiO2 or ZnO to activated carbon (AC) with microwave (MW) irradiation was proposed so as to assist efficient degradation of organic pollutants. A series of degradation experiments of sodium dodecyl benzene sulfonate (SDBS) were carried out under MW irradiation in the presence of AC/TiO2 or AC/ZnO. The influences of catalyst dose, irradiation time, initial SDBS concentration and solution acidity on the degradation were assessed in detail. The results showed that the addition of TiO2 or ZnO obviously promoted the degradation and AC/TiO2 system displayed higher catalytic activity under MW irradiation. Thus the method of MW irradiation with AC/TiO2 or AC/ZnO revealed many advantages of rapid degradation rate, short irradiation time, low cost, no residual intermediates and no secondary pollution in applications.

Synthesis of mono-dispersed m-BiVO4 octahedral nano-crystals with enhanced visible light photocatalytic properties

Mono-dispersed monoclinic bismuth vanadate (m-BiVO4) octahedral single crystals were synthesized by a simple hydrothermal route in the presence of sodium dodecyl benzene sulfonate (SDBS). Electron microscope observation revealed that the synthesized m-BiVO4 octahedral single crystals were grown with preferentially facets {120} and {021}. The size of these single crystalline octahedra could be facially adjusted in a broad range from 5 μm to less than 200 nm. The influences of additive SDBS, reaction time and acid concentration were studied to understand the formation process, and hence a typical super-saturation process combined Oswald ripening process was proposed. Furthermore, these octahedral single crystals exhibited excellent photocatalytic performance determined by the degradation of rhodamine B (RhB) under visible light irradiation.

2,2,6,6-Tetramethylpiperidine-1-oxyl-mediated living mini-emulsion polymerization of styrene under ambient pressure in a semi-batch process: effect of ascorbic acid

2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-mediated living mini-emulsion polymerization of styrene with feeding of an ascorbic acid aqueous solution throughout the polymerization was performed at 90 °C under ambient pressure. The concentrations of sodium dodecylbenzenesulfonate (SDBS) and ascorbic acid were varied to study the shell polymerization mechanism of latex particles and evolution of growing chains. Interactions between SDBS and ascorbic acid and incompatibility between ascorbic acid and styrene were evident from UV-visible analyses. High hydrophilicity of ascorbic acid in the aqueous phase was proved using a gravimetric method. Accordingly, the formation of a surface barrier on particles was proposed because of the interactions between SDBS and ascorbic acid. For higher SDBS concentration, the surface barrier on the particles was denser. Therefore, the polymerization rate decreased with increasing SDBS concentration. However, the polymerization rate increased with increasing ascorbic acid concentration. This was due to a higher consumption rate of TEMPO by ascorbic acid. Free TEMPO tended to reside in surface zones of the particles because of the surface activity between the aqueous and oil phases. The surface zones were thus the main loci where TEMPO was consumed by ascorbic acid. The estimated number-average molecular weight (Mn) of growing chains increased in a linear fashion with conversion. This indicated that the growing chains were produced via living mini-emulsion polymerization. For these growing chains, the estimated Mn and final polydispersity increased with increasing SDBS concentration. This was caused by a decrease in TEMPO concentration in the surface zones of particles with increasing SDBS concentration. The ‘livingness’ of polystyrene was identified by conducting bulk polymerization of chain extension. Based on the results obtained, a shell polymerization mechanism of latex particles was proposed, and living mini-emulsion polymerization was limited to the surface zones of particles. Copyright © 2010 Society of Chemical Industry

Determination of anionic surfactant in surface water by resonance light-scattering technology

A sensitive and rapid method, without any extraction procedure, for the determination of the anionic surfactant expressed in the terms of sodium dodecyl benzene sulfonate (SDBS) by the resonance light scattering (RLS) technique is described in this paper. In the pH value 3.0 Britton-Robinson (BR) buffer, Victoria blue B (VBB) reacted with SDBS and produced large particles which resulted in the remarkable enhancement of the RLS intensity of VBB. The enhanced RLS intensity of the assay system was proportional to the concentration of SDBS in the range of 0.08–3.0 mg L–1 and the correlation coefficient was r = 0.9996. The detection limit was 0.013 mg L–1. This method was applied to determine the anionic surfactant in the surface water samples and satisfactory results were obtained. The reaction mechanism was also studied and the interaction between VBB and SDBS was mainly governed by electrostatic effect and the π–π stacking effect.

Influence of sodium dodecylbenzene sulfonate on the structure and properties of carbon aerogels

This letter describes the effects that the surfactant, sodium dodecylbenzene sulfonate (SDBS), has on the structure and electrical properties of monolithic carbon aerogels (CA). Using organic sol–gel chemistry, a series of novel CA materials prepared with different concentrations of SDBS were characterized to evaluate the influence the surfactant had on the network structure of the resultant material. Addition of the SDBS surfactant to the sol–gel reaction mixture was shown to generate CA structures that had different pore sizes, higher densities and improved electrical conductivity than those prepared without the surfactant. These results are discussed in comparison with relevant sol–gel literature and theory.

Aggregation behavior of a water‐soluble terpolymer with vinyl biphenyl characterized by a fluorescent probe

AbstractA terpolymer (PAAP) of acrylamide, sodium 2‐acrylamido‐2‐methylpropane sulfonate, and vinyl biphenyl as a hydrophobic monomer was synthesized to obtain a polymeric oil‐flooding agent with low molecular weight and application in oil reservoirs with medium to low permeability. The intermolecular self‐assembling mechanisms in the PAAP solutions were investigated with a pyrene fluorescence probe as functions of the polymer concentration, surfactant, and temperature. The hydrophobically associating morphologies of PAAP in an unsalted solution were observed with scanning electron microscopy. The results show that the high solution viscosity of PAAP was due to the strong intermolecular hydrophobic associations of the biphenyl groups, and the critical association concentration was 0.05 g/dL for the unsalted and brine PAAP solutions. The nonpolarity and association degree in the hydrophobic microdomains were greatly influenced by the polymer concentration. With the addition of the optimum sodium dodecyl benzene sulfonate concentration, the interpolymer hydrophobic associations were strengthened remarkably via the connection of the surfactant with biphenyl groups from different polymer chains. The number and sizes of the aggregates increased in the range of 20–50°C. These results demonstrate that the thickening effect of the PAAP polymer in the aqueous solution was due to intermolecular associations of the biphenyl groups. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Influence of pH and SDBS on the Stability and Thermal Conductivity of Nanofluids

Aiming at the dispersion of nanoparticles which are regarded as the guide of heat transfer enhancement, we investigated the heat transfer enhancement of two water-based nanofluids, namely, water−Al2O3 and water−Cu mixtures. The absorbency, ζ potential, and thermal conductivity of the nanofluids were measured under different pH values and different sodium dodecylbenzene sulfonate (SDBS) dispersant concentrations. The results showed that the stability and thermal conductivity of nanofluids were highly dependent on pH values and SDBS concentrations of nanosuspensions; an optimal pH value and optimal SDBS concentration can result in the highest stability and thermal conductivity of the nanofluids. Therefore, the combined treatment with both the pH and the chemical surfactant concentration was recommended to improve the stability and thermal conductivity for practical applications of nanofluid.

Preparation of Silver Nanoplates in SDBS System

Silver nanoplates were prepared in the solution of sodium dodecyl benzene sulfonate (SDBS) and polyvinyl pyrrolidone (PVP) via reducing silver nitrate with hydrazine hydrate. X-ray diffraction (XRD) and Scanning electron microscope (SEM) were applied to identify phase and observe microstructure. The surface tension analysis showed that in SDBS + PVP system, the γ-C curve acted as dual-platform and the corresponding concentration turning points were C1 (0.8g/L) and C2 (6.0g/L) respectively. XRD analysis confirmed that the reduction product was element silver. SEM observation revealed that nano-plates silver were obtained when the SDBS concentration was between C1 and C2, otherwise spherical-shaped nanoparticles were synthesized.

Surfactant Effects on the Affinity of Plant Cuticles with Organic Pollutants

To precisely predict organics accumulation and crop safety, the affinity of fruit cuticles for naphthalene and 1-naphthol was investigated with the presence of three surfactants below and above the critical micelle concentration (CMC), including anionic sodium dodecylbenzene sulfonate (SDBS), cationic cetyltrimethylammonium bromide (CTMAB), and nonionic polyoxyethylene (20) sorbitan monolaurate (Tween 20). Tomato and apple cuticles with distinct compositions were selected. With increasing SDBS concentrations, apparent sorption coefficients (K(d)*) of 1-naphthol by both cuticles first increased a bit and then decreased slightly. The K(d)* of naphthalene by tomato cuticle is sensitive to SDBS concentration with a sharp increase and then decrease, whereas SDBS has little effect on naphthalene K(d)* by apple cuticle. For CTMAB with lower CMC, the naphthalene K(d)* decreased more quickly. Tween 20 seems to be ineffective on naphthalene sorption by both cuticles. Nevertheless, the intrinsic sorption coefficients (K(d)) were almost promoted by the coexisting surfactants, resulting from the cuticle-sorbed surfactant's plasticizing effect.