Lauryl Sulfate Surfactant Research Articles

Sodium Lauryl Sulphate Enhanced Solar Energy Conversion by Photogalvanic Effect of Rhodamine B‐Fructose in Artificial Light

AbstractThe present study has been done to improve the solar power and storage capacity of the Rhodamine B‐Fructose system with small Pt electrode by use of Sodium Lauryl Sulphate surfactant in the artificial light. With additional scope for reduction of the cost, the present study has shown greatly enhanced performance in terms of electrical parameters like power 336.05 μW, short‐circuit current 1150 μA, and conversion efficiency ∼11.28 %.

Preparation of an Injectable Macroporous α-TCP Cement

One of the most important characteristics of calcium phosphate cements is their resorbability when implanted in the body. However, the in vivo resorption rate is slow due to the lack of intrinsic open porosity. In this study, macroporous structures were obtained by mixing alpha-tricalcium phosphate (α-TCP) cement with a foamed liquid phase containing different concentrations of sodium hydrogen phosphate and non-ionic (Lutensol) or anionic (Sodium Lauryl Sulfate) surfactant. The cement paste was prepared by hand mixing in a system of two syringes connected by a polyvinyl chloride (PVC) valve, an environmentally friendly method. Solutions with Lutensol (L110) showed greater foamability than solutions with Sodium Lauryl Sulfate (SLS). Scanning Electron Microscopy characterization helped verify that the prepared samples showed a macroporous interconnected structure, and X-ray diffraction analysis evidenced the transformation of α-TCP into calcium deficient hydroxyapatite (CDHA). This study suggests that the calcium phosphate cement samples foamed with Lutensol may be further evaluated as suitable materials for bone filling.

Graphene Sheets with Modified Surface by Sodium Lauryl Sulfate Surfactant for Biomedical Applications

This work describes synthesis of graphene sheets with modified surface by sodium lauryl sulfate (SLS) surfactant using one-pot solvothermal reaction method. Effect of sodium lauryl sulfate surfactant amount on surface modification level of graphene sheets was investigated. Ether (-S-OR- at 762 cm-1 - 863 cm-1), thiocarbonyl (=C=S at 1050 cm-1 - 1176 cm-1) and sulfoxide (S-O, Vs and Vas at 1030 cm-1 - 1450 cm-1) functional groups released from sodium lauryl sulfate (SLS) surfactant during solvothermal reaction and attached on the surface of graphene sheets were detected by (attenuated total reflectance-fast Fourier infrared) ATR-FTIR spectroscopy. (Atomic force microscope) AFM observations revealed apparent surface of graphene sheets modified by surfactant molecules with an average multiple profile of graphene nanosheets ≈ 4.8 nm high. This synthesis way of surface modified graphene sheets can be considered as easy, one-step and cheap method for manufacturing of novel biosurface with graphene, as reinforcement for biopolymer coatings such as ultra-high molecular weight polypropylene (UHMWPE), metallic biomaterials (Ti and Ti alloys) and bioceramics as hydroxyapatite (HA).

Physical Changes by Mixture of Sodium Lauryl Sulfate and Non-ionic Surfactant

Physical Changes by Mixture of Sodium Lauryl Sulfate and Non-ionic Surfactant

Role of dual dopants in highly ordered crystalline polyaniline nanospheres: Electrode materials in supercapacitors

ABSTRACTAniline is oxidized by ammonium persulfate oxidant with a weak organic acid, 1,3‐(6,7)‐napthalene trisulfonic acid (NTSA), via an aqueous polymerization pathway to polyaniline (PANI) salt. The effects of the sodium lauryl sulfate surfactant, mineral acid [sulfuric acid (H2SO4)], and a combination of surfactant with mineral acid in the aniline polymerization reaction are also carried. These salts were designated as PANI–NTSA–dodecyl hydrogen sulfate (DHS), PANI–NTSA–H2SO4, and PANI–NTSA–DHS–H2SO4, respectively. Interestingly, PANI–NTSA–DHS showed a highly ordered crystalline sample with a nanosphere morphology. These PANIs were used as electrode materials in supercapacitor applications. Among the four salts, the PANI–NTSA–DHS–H2SO4 material showed higher values of specific capacitance (520 F/g), energy (26 W h/kg), and power densities (200 W/kg) at 0.3 A/g. Moreover, 77% of the original capacitance was retained after 2000 galvanostatic charge–discharge cycles with a Coulombic efficiency of 98–100%. PANI–NTSA–DHS–H2SO4 was obtained in excellent yield with an excellent conductivity (6.8 S/cm) and a thermal stability up to 235°C. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42510.

Study of enhanced photogalvanic effect of Naphthol Green B in natural sunlight

The photogalvanic cells based on Naphthol Green B sensitizer-Fructose reductant-Sodium Lauryl Sulphate surfactant has been studied in natural sunlight. The cell has been found workable in natural sunlight with greatly enhanced optimum cell performance. The 1159.2 μW power, 4500 μA short-circuit current, 1070 mV open-circuit potential, 14.49% efficiency and 240 min storage capacity (as half change time) has been observed in optimum cell fabrication conditions.

Aqueous, interfacial, and electrochemical polymerization pathways of aniline with thiophene: Nano size materials for supercapacitor

ABSTRACTAniline was mixed with thiophene and oxidized by ammonium persulfate in the presence of sulfuric acid via an aqueous polymerization pathway (PAT‐AP). Aqueous polymerization was also carried by sodium lauryl sulfate surfactant, and also by interfacial and electrochemical polymerization pathways. Polymers prepared were characterized by physical, spectral, and electrochemical methods. Nanofibers (30–60 nm diameter) was obtained in the case of aqueous polymerization pathway, whereas interfacial (40–60 nm) and electrochemical polymerization pathways show particulate (500–600 nm) morphology. Polymer samples were used as electrode materials in supercapacitor. Among the four different pathways, PAT‐AP nanofibers show higher capacitance of 614 F g−1 at 1 mV s−1. The values of specific capacitance, energy, and power densities of PAT‐AP were found to be 400 F g−1, 20 W h kg−1 and 1200 W kg−1, respectively, at a current density of 2 A g−1. The retention capacitance is 78% after completion of 1000 cycles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42013.

Surfactant and natural sunlight enhanced Photogalvanic effect of Sudan I dye

Photogalvanic cells (PG) have been extensively studied for solar power and storage at low intensity artificial sunlight. But, PG can be practically significant and applicable in daily life only when they are validated at natural sunlight intensity. Therefore, the present study of photogalvanics of Sudan I-Fructose with efficiency enhancer chemical such as Sodium Lauryl Sulfate (SLS) surfactant in alkaline medium has been used to observe their workable feasibility in natural sunlight with investigation for optimal fabrication parameters. The cell has been found workable in natural sunlight with greatly enhanced optimum cell performance compared to that for reported similar cells. The observed optimum cell performance in terms of maximum power, short-circuit current, open-circuit potential, conversion efficiency and storage capacity (as half change time) is of the order of 1081.1μW, 4200μA, 1048mV, 13.5%, and 31min, respectively.

Synthesis of highly crystalline polyaniline with the use of (Cyclohexylamino)-1-propanesulfonic acid for supercapacitor

Polyaniline (PANI) salt was prepared with 3-(Cyclohexylamino)-1-propanesulfonic acid (CAPS) as a novel dopant by aqueous polymerization pathway. Effects of sodium lauryl sulfate surfactant, mineral acid (H2SO4), and a combination of surfactant with mineral acid during the polymerization reaction were also determined. PANI-CAPS showed semicrystalline with flake-like morphology. The use of the sodium lauryl sulfate along with CAPS resulted in the formation of highly crystalline nanospheres with flake-like morphology. In order to find out the effect of surfactant, sodium lauryl sulfate was used in the reaction. The combination of sodium lauryl sulfate, CAPS, and H2SO4 brings about an extended nanosphere morphology. These polyaniline salts were used as electrode materials in the supercapacitor application, in a symmetric two-electrode cell configuration. The values of specific capacitance, energy, and power densities of PANI-CAPS-DHS-H2SO4 material at 2 mA cm−2 were 495 F g−1, 90 kJ kg−1, and 120 J Kg−1 s−1, respectively. Moreover, 85 % of the original capacitance was retained after 3,000 galvanostatic charge–discharge cycles with a coulombic efficiency of 96–99 %. The value of phase angle is close to 90 at low frequencies, indicating a good capacitive behavior.

Single Step In Situ Synthesis and Optical Properties of Polyaniline/ZnO Nanocomposites

Polyaniline/ZnO nanocomposites were prepared by in situ oxidative polymerization of aniline monomer in the presence of different weight percentages of ZnO nanostructures. The steric stabilizer added to prevent the agglomeration of nanostructures in the polymer matrix was found to affect the final properties of the nanocomposite. ZnO nanostructures of various morphologies and sizes were prepared in the absence and presence of sodium lauryl sulphate (SLS) surfactant under different reaction conditions like in the presence of microwave radiation (microwave oven), under pressure (autoclave), under vacuum (vacuum oven), and at room temperature (ambient condition). The conductivity of these synthesized nanocomposites was evaluated using two-probe method and the effect of concentration of ZnO nanostructures on conductivity was observed. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-visible (UV-VIS) spectroscopy techniques were used to characterize nanocomposites. The optical energy band gap of the nanocomposites was calculated from absorption spectra and ranged between 1.5 and 3.21 eV. The reported values depicted the blue shift in nanocomposites as compared to the band gap energies of synthesized ZnO nanostructures. The present work focuses on the one-step synthesis and potential use of PANI/ZnO nanocomposite in molecular electronics as well as in optical devices.

Use of conventional surfactant media as surrogates for FaSSIF in simulating in vivo dissolution of BCS class II drugs

The usefulness of selected conventional surfactant media to enhance dissolution of BCS class II drugs similarly to fasted state simulated intestinal fluid (FaSSIF) and to predict the absorption of drugs in vivo was evaluated. Dissolution behavior of danazol (Danol®), spironolactone (Spiridon®) and N74 (phase I compound) was compared between FaSSIF, containing physiological levels of sodium taurocholate (STC) and lecithin, and dissolution media containing various concentrations of anionic surfactant, sodium lauryl sulfate (SLS) or non-ionic surfactant, polysorbate (Tween) 80. Although these media differed largely in their solubilization ability, micelle size, diffusivity and surface tension, similar dissolution enhancing levels were achieved between FaSSIF and drug-specific concentrations of conventional surfactants. The dissolution enhancement was shown, however, to be important only for danazol and N74, molecules that are characterized by high hydrophobicity. An in vivo pharmacokinetic dog study was carried out with N74. Comparison of observed plasma profiles with simulated profiles obtained using compartmental absorption and transit model (CAT) indicated that 0.1% SLS medium was the best to predict in vivo plasma profiles and pharmacokinetic parameters ( C max and AUC). This study demonstrates the potential of substituting FaSSIF with more simple and cost-effective conventional surfactant media. Use of in vivo prognostic amounts of synthetic surfactants in dissolution testing could largely assist in industrial drug development as well as in quality control purposes.

Inverted emulsion polymerization route to polyaniline-3D nanofiber network using sulfonated-p-cresol as novel dopant

Sulfonated-p-cresol (SPC) was used as novel dopant for the first time in the synthesis of polyaniline in 3D nanofiber networks (PANI-3D). Polyaniline in 3D nanofiber network was prepared using organic solvent soluble benzoyl peroxide as oxidizing agent in presence of SPC and sodium lauryl sulfate (SLS) surfactant via inverted emulsion polymerization pathway. The influence of synthesis conditions such as the concentration of the reactants, stirring/static condition, and temperature etc., on the properties and formation of polyaniline nanofiber network were investigated. Polyaniline in 3D nanofiber network with 40–160 nm (diameter), high yield (134 wt % with respect to aniline used), and reasonably good conductivity (0.1 S/cm) was obtained in 24 h time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Effect of surfactant on voltammetric behaviour of ornidazole

The objective of the present work is to develop a voltammetric method for the determination of ornidazole in pharmaceutical formulations and it also deals with the beneficial use of surfactants in the catalysis of electrode reactions. The proposed method is rapid and sensitive for the qualitative and quantitative analysis of ornidazole in solubilized systems. The voltammetric behaviour of ornidazole has been studied in different surfactant media viz., anionic, cationic, non-ionic surfactants over the pH range 2.5 to 12.0 in phosphate buffer (0.2 M). Addition of non-ionic surfactant (Tween 20) to the ornidazole containing electrolyte enhanced the reduction current signal while the anionic surfactant sodium lauryl sulphate and cationic surfactant cetyltrimethylammonium bromide showed a small enhancement in peak current. The mechanism of reduction has been postulated on the basis of controlled potential electrolysis, coulometry and spectral analysis. The reduction process is irreversible and was diffusion controlled. Analytical method with adequate precise and accuracy was developed for the determination of ornidazole with linear concentration range 4.0 × 10 −3 to 4.0 × 10 −6 mol L −1. The lower limit of quantification (LOQ) and the lower limit of detection (LOD) were found to be 1.2 × 10 −6 and 3.6 × 10 −7 mol L −1 respectively. The analysis of ornidazole in its pharmaceutical formulation exhibited the mean recovery of 98% for the reduction peak.

Effect of Surfactant Concentration and Operating Temperature on the Drop Size Distribution of Silicon Oil Water Dispersion

The effect of sodium lauryl sulphate (SLES) surfactant and the operating temperature on the drop size distribution of a 350 cSt Dow Corning 200 series oil water dispersion was successfully studied. The dispersion was prepared in a standard 6 litres mixing tank at different impeller speeds. A measurement of the SLES critical micelle concentration (CMC) at 25°C was carried out. The interfacial tension of silicon oil water under various SLES concentration at a temperature range of 25 to 80°C was accomplished. Results showed that the interfacial tension of the silicon oil water decreased as the operating temperature increased and as the surfactant concentration increased. When the operating temperature was increased at the highest SLES concentration tested, a decrease of d 32 was observed. This was attributed to the possibility of hydration of the surfactant at high temperature. Same behavior was observed when measuring the drop size distribution at constant temperature but different SLES concentration. It was found that the mean drop size decreases with mixing time. Different slopes of the change of the median drop size with time were obtained for different SLES concentration. For the same concentration, the slope changes after 1 hour. The degree change of the slope is due to the change of interfacial area of the oil water as mixing time elapsed and the depletion of the surfactant concentration.

Stability in Styrene/HD Miniemulsions Containing a RAFT Agent

Styrene miniemulsions stabilized by sodium lauryl sulfate surfactant and hexadecane costabilizer were prepared and polymerized with the RAFT (reversible addition fragmentation chain transfer) agent cumyl dithiobenzoate. The instability noted by others in controlled radical miniemulsion polymerizations via RAFT was seen in these reactions as well and was investigated to determine the nature of this instability. Clues were found in the phase-separated emulsions and latexes as they evolved during polymerizations. Methods of improving the stability provided additional information along with some control studies excluding the RAFT agent. Instability was attributed to an initial Ostwald ripening leading to large micron-size droplets with a relatively low concentration of the RAFT agent and hexadecane, which separated as an oil layer upon centrifugation. At the other end, the Ostwald ripening created small droplets containing high concentrations of the RAFT agent, and these coagulated to form droplets significan...

Thermal stability and structure of electroactive polyaniline–fluoroboric acid–dodecylhydrogensulfate salt

Oxidation of aniline by emulsion polymerization pathway using benzoyl peroxide oxidant in the presence of fluoroboric acid and sodium lauryl sulfate surfactant leads to incorporation of both acid group as well as surfactant group onto the polyaniline chain as dopants i.e. formation of polyaniline–fluoroboric acid–dodecylhydrogensulfate salt (PANI–HBF 4–DHS). Amount of dopants such as fluoroboric acid (HBF 4), dodecylhydrogensulfate (DHS) and water present in the PANI–HBF 4–DHS was found out for the first time. Electrochemical activity and rheological stability of the polymer were determined. Thermal stability of PANI–HBF 4–DHS was determined by subjecting the polyaniline salt in macroscale at four different temperatures (100, 150, 200 and 250 °C). Structure, composition and thermal stability of polyaniline salt were determined by chemical analysis, conductivity, IR, UV/vis, XRD spectral measurements from the heat treated samples. Polyaniline salt contains 8.3 wt% water, 22.4 wt% HBF 4 and 15.4 wt% DHS at ambient temperature. Upon vacuum, polyaniline salt loses 4.7 wt% water and on heating the sample at 100 °C it loses the remaining 3.6 wt% water. On further heating polyaniline salt loses its dopants and at 250 °C it loses both the dopants almost completely. Polyaniline salt on heating undergoes cross-linking even at 100 °C and however, conductivity (3 × 10 −2 S/cm) of polyaniline salt was found to remain almost the same up to 150 °C.

Synthesis of Polypyrrole Using Benzoyl Peroxide as a Novel Oxidizing Agent

AbstractSummary: Benzoyl peroxide is used as an oxidizing agent for the first time in the synthesis of conducting polypyrrole. Synthesis of polypyrrole is commonly performed by chemical oxidative polymerization using water‐soluble oxidizing agents. In this work, polypyrrole was prepared using organic solvent‐soluble benzoyl peroxide as an oxidizing agent in the presence of p‐toluenesulfonic acid (p‐TSA) and sodium lauryl sulfate (SLS) surfactant via the inverted‐emulsion‐polymerization technique. During polymerization, SLS is converted to dodecyl hydrogensulfate (DHS) and incorporated on to polypyrrole along with p‐TSA dopant, indicating SLS is acting as emulsifier as well as dopant. The influence of synthesis conditions such as the duration of the reaction, the temperature, the concentration of the reactants, etc., on the properties of polypyrrole was investigated to determine the optimum conditions for the synthesis of polypyrrole salt. Polypyrrole was obtained in a reaction time of 1 h with high yield (154 wt.‐% with respect to pyrrole used) and good conductivity (2 S · cm−1). The conductivity of polypyrrole‐salt was found to be nearly the same even after seven months of storage at ambient temperature (1.7 S · cm−1). magnified image

Effects of surfactants on the microstructure and some intrinsic properties of porous building ceramics fabricated by gelcasting

Porous building ceramics were fabricated by gelcasting and the effects of surfactants on their microstructure and some intrinsic properties such as sound absorption and thermal conductivity were investigated. Preliminary tests on solubility in water, foaming capacity and foam stability of different surfactants were carried out to evaluate their foaming ability. Porous ceramic fabricated using an anionic ammonium lauryl sulphate surfactant with large foaming ability showed lower density, higher open and total porosities, and broad pore size distribution. Total porosities of three porous ceramics fabricated using different surfactants were found to be similar to that of the corresponding air volume fractions of the three foamed slurries. Sound absorption and thermal conductivity of the porous ceramics as construction tile were further characterized. Porous ceramic with higher porosity presented a higher value of sound absorption coefficients and lower thermal conductivity.

Synthesis of SiO2/Polystyrene Nanocomposite Particles via Miniemulsion Polymerization

The SiO(2)/polystyrene nanocomposite particles were synthesized through miniemulsion polymerization by using sodium lauryl sulfate surfactant (SLS), hexadecane costabilizer in the presence of silica particles coated with methacryloxy(propyl)trimethoxysilane. Core-shell or other interesting morphology composite particles were obtained depending on the size of the silica particles and the surfactant concentration employed. By adjusting these parameters, it was possible to control the size and morphology of the composite particles.

Benzoyl peroxide oxidation route to polyaniline salt and its use as catalyst in the esterification reaction

Aniline was oxidized to polyaniline salt using benzoyl peroxide as an oxidizing agent in the presence of sulfuric acid and sodium lauryl sulfate surfactant. The polymer sample was characterized using infrared, X-ray diffraction, particle size, resistance and density measurements. Polyaniline salt was used as catalyst for the esterification reaction of carboxylic acids with methanol. The process is being reported for the first time. Preparation of catalyst, recovery and reusability of the catalyst are found to be good.