Various Types Of Surfactants Research Articles

Thermal insulation and fire protection plaster for FRP systems incorporating aerogel nanoparticles and phyllosilicates

Fiber Reinforced Polymers (FRP) Systems are the most advanced systems in structural repair and strengthening field for their minimal time of application, limited space needed, and high durability. However, FRP systems still have a major drawback that limits their utilization in many projects, namely low fire-resistance. A novel material that was introduced lately with a substantial thermal performance is Aerogel, which has been widely utilized in other fields. This study attempted to develop fire-protective plaster incorporating nano silica-aerogel particles and phyllosilicates. During the experimental process, different surfactants were assessed as wetting agents, and their impact on both cement and mineral matrices. Finally, the selected plaster was evaluated under fire conditions. The results reveal that aerogel incorporation in mineral (gypsum) matrix was successfully achieved using various types of surfactants. The mechanical and thermal performance of the developed plasters were promising, with a fire-rating performance reaching 82 minutes for FRP system.

Effects of Surfactants on the Aggregation of 6,6'-Disubstituted Thiacarbocyanine Dyes in Aqueous Solutions

The aggregation properties of a number of 6,6'-substituted thiacarbocyanine dyes were studied by spectral-fluorescent methods: T-304, T-306, T-307, T-336 and, for comparison, thiacarbocyanine Cyan 2, which has no substituents in the 6,6'-positions, in aqueous buffer solutions and in the presence of various types of surfactants. The method of moments was used to characterize the absorption spectra (band positions, width, shape). Substituents in the 6,6'-positions significantly increase the ability of dyes T-304, T-306, T-307, T-336 to aggregation (dimerization, as well as to the formation of disordered aggregates with broad low-intensity absorption spectra). The introduction of surfactants leads to rearrangement of the spectra associated with the complex nature of the equilibria between monomers and aggregates of various structures (including surfactant molecules, if present), in particular, with a decrease in the contribution of disordered aggregates. However, the decomposition of dimeric aggregates of 6,6'-substituted cyanines is observed only at very high surfactant concentrations (~20 CMC and higher, where CMC is the critical micelle concentration). At the same time, the passing of surfactant concentrations through CMC does not significantly affect the spectral-fluorescent properties of the dyes, which is probably due to rather strong interactions of the dyes with individual surfactant molecules and premicellar associates of surfactants.

Bottle test technique for separating water-in-sunflower oil emulsion under an application of electric field stabilised by surfactant and hydrolysed polyacrylamide

The efficacy of separating water-in-oil emulsions depends on the stability of the emulsion, which is influenced by the interaction of the polymer and surfactant at the oil–water interface. We examined the role of hydrolysed polyacrylamide and surfactants on the stability of water-in-oil emulsions. The effects were investigated by implementing bottle tests (BT) and electrocoalescence bottle tests (EBT) using various types of surfactants over a wide range of concentrations. For a high volume fraction (10% v/v) of emulsion, the BT study showed 80% of separation in a short duration. At a small volume fraction (2% v/v), efficient separation was achieved by applying an electric field. These studies were further extended to a hybrid mode of operation, combining 1 kV/cm, non-uniform DC electrical fields at a temperature of 60 °C, to achieve maximum separation efficiency of up to 91% within 10 min for deionised water when the volume fraction of water in the emulsion was 2%. Under the same conditions, we observed an impressive 88% separation for surfactant and polymer-stabilised emulsions. HPAM does not affect interfacial tension due to its lack of amphiphilic character. However, it significantly increases the viscosity of the dispersed phase by forming a network that restricts coalescence, thereby affecting the separation rate. Surfactants enhance stability by reducing interfacial tension (IFT) and forming a protective layer around the droplet. The findings provide valuable insights for optimising separation processes using the synergy of the heating and electric fields. The study successfully and efficiently separates oil and water, even when dealing with challenging emulsions containing polymers and surfactants, by combining heating and electrical methods.

Organoclays Based on Bentonite and Various Types of Surfactants as Heavy Metal Remediants

The rapid industrial development of civilization has led to the need for the development of new materials to clean up chemically contaminated wastewater and soils. Organoclays, based on smectite minerals and various types of surfactants, are one of the most effective sorbents for adsorbing organic and inorganic pollutants. Organoclays are clay minerals that have been modified by the intercalation or grafting of organic molecules. The main mechanism of interaction between organic substances and organoclays involves the adsorption of the substances onto the surface of the clay mineral, which has an expanded structural cell. Various types of surfactants can be used to synthesize organoclays, including cationic, anionic, and amphoteric surfactants. Each type of surfactant has different properties that affect the clay’s ability to sorb. Cationic forms of trace elements, such as heavy metals, can also be adsorbed by organoclays. Data on the adsorption of these substances by organoclays are provided, along with information on how to synthesize them using various surfactants. This review also discusses the main mechanisms of interaction between these substances and clays and the various methods used to create organoclays. It is clear that the adsorption of heavy metals by organoclays is not influenced by their structure or properties, as they belong to the category of surfactant, but rather by their overall chemical structure and characteristics. The wide variety of surfactant types leads to different effects on the adsorption properties of trace elements.

A universal method for determining the detergent effect of surfactants

Surfactants are indispensable in industrial applications today due to their wetting, emulsifying, dispersing, cleansing, and detergent properties. The use of surfactants extends from the cosmetic industry to the petroleum industry and beyond.Their characteristics and effectiveness can be assessed through various standardized tests, and based on these methods, their applications can be determined. However, there is a lack of a universally applicable testing method for one crucial and complex property: the detergent effect.The detergent effect refers to the removal of unwanted contaminants from a solid surface. However, cleaning is not solely attributed to the surfactant but to the appropriate combination of various factors, whose synergistic effect reduces surface contamination. The most significant factors influencing detergent effect include the characteristics and nature of the contaminants, properties of the cleaning solution (surfactant concentration and composition, water hardness, enzymes, etc.), temperature, washing time, and hydrodynamic conditions. Additionally, the presence of electrolytes, pH of the cleaning solution, and detergent foaming properties may also play important roles.Our goal was to develop a detergent effect testing methodology that is not specific to any particular application domain but offers a straightforward and easy-to-implement solution for comparing the detergent effect of various types of surfactants.•The study presents a method for determining detergent effect of surfactants.•The method is universal and suitable for the evaluation of any type of surfactant.•The method is low-cost and easy to perform.

Влияние различных типов поверхностно-активных веществ на эмиссию газов и микробиоту жидкой фракции навозных стоков

Various surfactants are widely used in modern industrial animal husbandry. As part of detergents and pharmacological veterinary preparations, surfactants inevitably fall into manure effluents (ME), resulting in a change in the properties of ME. The study of the effect of various types of surfactants on the gas release and microbiota of the liquid fraction (LF) of ME was carried out on the example of surfactants with different biocidal activity: sodium laureth sulfate – anionactive surfactant (AS), lauryldimethylamine oxide – nonionic surfactant (NS) and benzalkonium chloride – cationic surfactant (CS). The studies were conducted under laboratory conditions. The total observation time since the introduction of additives in the LF (0,01 g per 1 liter) was 14 days. The obtained data shows changes in the dynamics of greenhouse gases (CH4 and CO2) and odor-forming substances (H2S, NH3, RSH) emission, as well as in the composition of the microbiota of biofilms and bacterioplankton, under the influence of surfactants. The dynamics of the CH4 emission differ from those of other gases. The use of CS leads to a gradual increase in CH4 emission a week after application. This may be due to increased permeability of the cytoplasmic membranes of methanogenic archaea with increased chemical resistance. The application of various types of surfactants into the LF has different effects on the dynamics of the odor-forming substances emission, and the active emission period of mercaptans becomes longer. The highest level of ethyl mercaptan was observed in the option with NS. There was no significant difference in the effect of low concentrations of various surfactants on the microbiota of LF, however the AS has a more pronounced bacteriostatic effect on set of indicators. The most tolerant to the effects of all types of surfactants were Clostridia, which dominates the microbiota biofilms and bacterioplankton. Fungi were the second most abundant in biofilms of the LF.

Permeability of Dimethyl Phthalate Through Human Skin Models – Health Risk Assessment

AbstractDimethyl phthalate (DMP) is used widely in cosmetics and personal care products as a solvent, skin penetrant, moisturizer and softener as well as an anti-cracking agent. Dermal absorption is one of the major exposure routes for lower molecular weight phthalates such as DMP and assessing their dermal permeability is important for evaluating the impact and toxicity of such compounds in humans. The aim of this study was to evaluate DMP permeability through different human skin models (Strat-M® synthetic membrane, in vitro reconstructed human epidermis and human dermatomed skin) using solutions containing various types of surfactants, as a simulation of the types of mixtures occurring in cosmetics and personal care products, in order to ascertain the impact that surfactants can have on skin permeability. The results have shown that human skin is the least permeable of the used skin models, and that surfactants (in particular cationic and non-ionic) lead to a significant increase of DMP permeability through all skin models. The performed risk assessment however shows that, for all tested models, the margin of safety was not exceeded.

The effect of surfactant type and concentration on the pore structure of alumina aerogels

Alumina aerogels are excellent materials for thermal insulators used at high temperatures due to the good thermal stability of aluminum oxide. In this study, alumina aerogels treated with various types of surfactants (non-ionic (Triton X-100), cationic (cetyltrimethylammonium bromide), or anionic (sodium dodecyl sulfate)). The effect of the surfactant depended on the charge-charge interactions between it and the cationic inorganic species in the aluminum precursor. As determined by using small-angle scattering and pore volume change measurements, these interactions induced a change in the pore structure that could be controlled by controlling the concentration of the surfactant. The hindrance effect due to the ionic interference was more pronounced at a higher surfactant concentration than at a lower one. Thus, the concentration of surfactant plays an important role in determining the pore structure of the alumina aerogel.

Surfactants-surface active agents behind sustainable living

Abstract Surfactants are surface active agents. They are mainly chemicals, when added to water will reduce the surface tension of water and thus increases wettability on the given surface. Surfactants normally carry hydrophilic and hydrophobic ends among which hydrophilic end connects to water layer. The hydrophobic part connects between aqueous phase and the given hydrophobic surface through the hydrophobic end. However, these surfactants act as emulsifying agents or foaming agents. Further the chemistry behind the action of surfactants is introduced for the readers. Surfactants can be classified based on origin, charge on heads, solubility of water etc. and is specified in this paper. Also synthesis of various types of surfactants is carefully incorporated in the chapter. The chapters dwells in detail the various sustainability related applications of surfactants which is relevant for sustainable living in the society.

Effect of surfactant type on the magnetic and morphological properties of NiFeO4 / reduced graphene oxide composites

A systematic study of the effect of various types of surfactants (polyethylene glycol, Trinon X-100 and cetyltrimethylammonium bromide) and subsequent annealing on the magnetic ordering and morphology of the nickel ferrite / reduced graphene oxide composite materials has been carried out. Hydrazine hydrate has been used both as an agent to initiate precipitation and as a reducing agent to remove oxygen functionality from the surface of graphene oxide particles. To characterize the material, Mössbauer spectroscopy and nitrogen absorption porosimetry have been used. The obtained result suggests a new way for one-pot synthesis of NiFe2O4/rGO composite materials with controlled magnetic ordering and porous structure.

Role of surface‐active materials (amphiphiles and surfactants) in the formation of nanocolloidal dispersions, and their applications

AbstractAmphiphiles and surfactants are surface‐active molecules with special properties at interfaces, and they can undergo different modes of self‐association forming colloidal entities in solution. They can also stabilize other colloidal dispersions including nanoparticles, and help the formation and protection of nanodispersions resulting from chemical reactions. In this study, we have discussed the formation, properties, and applications of such nanocolloid‐like species formed in solution by different methods with special stress on various types of surfactants. Nanoparticles show the difference in melting point, electrochemical properties, conductance, etc., from their corresponding bulk material. Classical thermodynamics is used to explain this property. The basics of such processes, their types, morphology, stability, and usefulness have been presented and discussed. The types of assemblies that arise from the self‐associations of the amphiphiles, and surfactants under different conditions (i.e., micelles, reverse micelles, vesicles, liposomes, niosomes, etc.) have been also presented. Examples of their types, morphologies, transformations, and applications in relation to the stability, and functions of nanodispersions or nanocolloids are exemplified with multiple illustrations from earlier as well as recent research. The use of biosurfactants and block copolymers is also discussed. The stabilization of nanoparticles by “capping” has been discussed in some detail. A short account of the hydrothermal and solvothermal processes of synthesis of nanomaterials using amphiphiles as templates has been also presented. The multiple applications of amphiphile‐mediated nanoscience have been briefly presented and discussed.

Dual-emission samarium macrocycle as a lab-on-a-molecule enables high-throughput discrimination of anionic sulfonate surfactants

Nowadays, it is still a huge challenge to efficiently discriminate of analogous anionic sulfonate surfactants, which are noxious xenobiotics related to many safety concerns of environment and life. Recently, great advances in orthogonal detection have shown the great advantages of principal component analysis (PCA) to construct a comprehensive statistical method for sensing signals in recognizing more analytes with similar structures. Inspired by sensor arrays, we propose a new ‘one-element-two-channel’ protocol upon a dual-emission samarium macrocycle Sm-2o as the lab-on-a-molecule, containing two isolated emissions of macrocycle (443 nm) and Sm(III) (643 nm) emitters as two fluorescence channels. Herein, these targeted surfactants instruct original fluorescences of Sm-2o to generate diverse sensing signals which can finally convert into unique fingerprint patterns and distinguish four anionic surfactants (SDS, SDSO, SCI and AOS) from other ten ones, even their proportional concentrations. Significantly, this high-throughput discrimination is realized by different receptor-analyte interactions and the structure transformation of Sm-2o in diverse microenvironments formed in various types of surfactants. Furthermore, these sensing systems also show satisfactory discrimination and semiquantitation performances for mixtures of anionic surfactants, especially the SDS and SDBS, in real water sample, revealing the practicability of our lab-on-a-molecule probe. On the basis of the PCA method, this work provides a vital reference for the design and application of multianalyte chemosensors.

КОМПЛЕКСООБРАЗОВАНИЕ ЭРИОХРОМЦИАНИНА R С ИОНАМИ АЛЮМИНИЯ И ЖЕЛЕЗА (III) В ПРИСУТСТВИИ ПАВ

The effect of various types of surfactants on the complexation of aluminum and iron (III) ions with eriochromecyanine R have been studied. According to the light absorption spectra of the dye and complexes with metal ions without surfactants and in the presence of catamine AB, oxyphos B, and syntanol DS-10 at various pH and the concentration of surfactants determined the optimal conditions for complexation have been determined. Oxyphos B has a negative effect on the spectrophotometric characteristics of the complexes. Syntanol DS-10 has practically no effect. The presence of catamine AB causes a bathochromic shift in the maximum of light absorption of the complex, increases the contrast of the photometric reaction and the value of the extinction coefficient. The composition of the complexes in the absence and in the presence of catamine AB has been determined by saturation and isomolar series methods. The presence of catamine AB increases the molar ratio of metal: reagent in the complex from 1: 2 to 1: 3. By Babko's method, conditional stability constants of the complexes have been determined, calibration curves have been constructed, and molar light absorption coefficients have been calculated.

Amphipathic environments for determining the structure of membrane proteins by single-particle electron cryo-microscopy.

Over the past decade, the structural biology of membrane proteins (MPs) has taken a new turn thanks to epoch-making technical progress in single-particle electron cryo-microscopy (cryo-EM) as well as to improvements in sample preparation. The present analysis provides an overview of the extent and modes of usage of the various types of surfactants for cryo-EM studies. Digitonin, dodecylmaltoside, protein-based nanodiscs, lauryl maltoside-neopentyl glycol, glyco-diosgenin, and amphipols (APols) are the most popular surfactants at the vitrification step. Surfactant exchange is frequently used between MP purification and grid preparation, requiring extensive optimization each time the study of a new MP is undertaken. The variety of both the surfactants and experimental approaches used over the past few years bears witness to the need to continue developing innovative surfactants and optimizing conditions for sample preparation. The possibilities offered by novel APols for EM applications are discussed.

ВЛИЯНИЕ ПОВЕРХНОСТНО-АКТИВНЫХ ВЕЩЕСТВ НА СПЕКТРОФОТОМЕТРИЧЕСКИЕ ХАРАКТЕРИСТИКИ КОМПЛЕКСОВ СКАНДИЯ С ЭРИОХРОМЦИАНИНОМ R

The effect of various types of surfactants on the complexation of scandium ions with eriochromecyanine R. The optimal conditions were determined from the light absorption spectra of the dye and complexes with metal ions without surfactants and in the presence of catamine AB, oxyphos B and syntanol DS-10 at various pH values and surfactant concentrations complexation. The presence of catamine AB causes a bathochromic shift in the maximum of light absorption of the complex, increases the contrast of the photometric reaction and the value of the extinction coefficient. The composition of the complexes in the absence and in the presence of catamine AB was determined by saturation and iso- molar series methods. It also increases the molar ratio of Sc : eriochromecyanine R in the complex from 1:2 to 1:3. The conditional stability constants of the complexes were determined by Babko's method, calibration curves were constructed, and the coefficients of molar light absorption were calculated. Oxyphos B has a negative effect on the spectrophotometric characteristics of the complexes. Syntanol DS-10 has practically no effect.

Screening the baseline fish bioconcentration factor of various types of surfactants using phospholipid binding data.

Fish bioconcentration factors (BCFs) are commonly used in chemical hazard and risk assessment. For neutral organic chemicals BCFs are positively correlated with the octanol-water partition ratio (KOW), but KOW is not a reliable parameter for surfactants. Membrane lipid-water distribution ratios (DMLW) can be accurately measured for all kinds of surfactants, using phospholipid-based sorbents. This study first demonstrates that DMLW values for ionic surfactants are more than 100 000 times higher than the partition ratio to fish-oil, representing neutral storage lipid. A non-ionic alcohol ethoxylate surfactant showed almost equal affinity for both lipid types. Accordingly, a baseline screening BCF value for surfactants (BCFbaseline) can be approximated for ionic surfactants by multiplying DMLW by the phospholipid fraction in tissue, and for non-ionic surfactants by multiplying DMLW by the total lipid fraction. We measured DMLW values for surfactant structures, including linear and branched alkylbenzenesulfonates, an alkylsulfoacetate and an alkylethersulfate, bis(2-ethylhexyl)-surfactants (e.g., docusate), zwitterionic alkylbetaines and alkylamine-oxides, and a polyprotic diamine. Together with sixty previously published DMLW values for surfactants, structure-activity relationships were derived to elucidate the influence of surfactant specific molecular features on DMLW. For 23 surfactant types, we established the alkyl chain length at which BCFbaseline would exceed the EU REACH bioaccumulation (B) threshold of 2000 L kg-1, and would therefore require higher tier assessments to further refine the BCF estimate. Finally, the derived BCFbaseline are compared with measured literature in vivo BCF data where available, suggesting that refinements, most notably reliable estimates of biotransformation rates, are needed for most surfactant types.

Toxicity Evaluation of Household Detergents and Surfactants Using Zebrafish

There are concerns regarding the toxicity of household detergents to humans and aquatic organisms. There are various types of surfactants, which are the main components of detergents, and each detergent product has a different formulation. Therefore, high-throughput technologies capable of analyzing a large number of samples rapidly and accurately are required for research on detergent toxicity. In this study, image analysis techniques were used to quantify the locomotor activities from captured images using larval zebrafish (Danio rerio). When the 135-min time-lapse imaging was completed, the damage to the body of the animals was examined using a microscope. Additionally, we determined the animal survival and LC50. Nonionic decyl glucoside (APG-C10), one of the alkyl polyglucosides (APGs), exhibited the lowest toxicity, whereas linear alcohol ethoxylate (LA-9) exhibited the highest toxicity. AOS (α-olefin sulfonate), LAS (linear alkylbenzene sulfonate), and APG-600 showed moderate toxicity between LA-9 and APG-C10. Commercial detergents exhibited various degrees of toxicity, and there was a linear relationship (R2 = 0.776) between locomotor activity and survival percentage of animals.

Experimental studies of the removal properties of liquid and solid foaming surfactants

Using the laboratory model of a well, foaming and removal properties of liquid and solid surfactants (savenol, light and dark stinol, Sofir M2, TEAS and Nadra) are studied. The authors determine experimentally the height of the level of the foam in the glass column at the end of the foam-forming process and the duration of re-moving half volume of liquid out of the foam. Using height and duration values, the authors determine the multi-plicity and stability of the foam. Based on the results of experiments on the laboratory model of the well, a graph-ical dependence of the multiplicity and stability of the foam on the mass concentration of surfactants in fresh and salt water, in mineralized water with the addition of hydrocarbon condensate for various temperatures is con-structed. Based on the results of experimental studies, the influence of the concentration of surfactants in a foam-ing liquid, the salinity of water, hydrocarbon condensate and temperature on the foaming ability of liquid and solid surfactants for the removal of liquid from watered gas and gas condensate wells is analyzed. The authors determine the optimal values of the concentrations of foaming surfactants in aqueous solutions. Above these val-ues the multiplicity and stability of the foam varies slightly. It has been established that the outflow properties of the solid Nadra surfactant are the best in saline water and in solutions with hydrocarbon condensate, in contrast to the investigated liquid surfactants. Based on experimental studies, the patterns of foaming of aqueous surfac-tant solutions with modeling bottomhole temperature (from 20 to 80 °) are established. The authors recommend the use of various types of surfactants under different operating conditions of wells with a high fluid content in the well production. Foaming surfactants are supplied to the bottom of the well in the form of aqueous solutions and samples of solid surfactants. As a result, the foamed formation fluid brings to the surface not only the liquid phase, but also the solid particles that accumulate at the bottom due to corrosion of the pipe metal, the destruction of cement stone and rock of the bottomhole formation zone.

A new approach to dispersing and stabilizing graphene in aqueous nanofluids of enhanced efficiency of energy-systems

Owing to its severe hydrophobicity, graphene (G) as on dispersed in a fluid usually deposits therein after a short interval of time. Understanding the G-behavior and the factors affecting its deposition could pave a way for creating a substantially stable nanofluid (NF). In this work, a novel method of stabilizing a G-NF is described with selective examples. The results can be extended to develop the science and technology of G-NFs in general. Electrohydrodynamic forces are used as a controlling factor in the presence of magnetic nanoparticles (MNPs). Contrary to common chemical methods employed for preparing G-NFs, which depend on establishing bonds between the components, the physical method introduced in this article could be used as a novel approach not only to dispersing G in a fluid carrier but also to resolve the common problems originating from utilizing such chemical methods as increasing thermal resistance through adding various types of surfactants. The effects of various factors on the stability of the G-NFs are described. By increasing 50%, 100% and 170% of G, the G sitting rate increased by 43%, 82%, and 109%, respectively. With the addition of one, two and three layers to a G-monolayer, the G sitting rate grew by 77%, 153%, and 263%, respectively. Further, the G-behavior in the presence of MNPs and varied intensive electric fields were studied to optimize an electric field that could stabilize a single-layer G sheet in aqueous NFs. Adding MNPs promptly stabilizes a water/ethylene glycol/G NF in an applied electric field of 0.05 V/Å.

Influence of surfactants on the interaction of copper oxide nanoparticles with vital proteins

Abstract Herein, we report the biochemical interaction between copper-oxide nanoparticles (CuO NPs) and vital biomolecules viz., deoxyribonucleic acid (DNA) and vital proteins such as bovine serum albumin (BSA), human serum albumin (HSA) and collagen in presence of various types of surfactants (non-ionic, cationic and anionic surfactants). Bare CuO NPs are synthesized by wet chemical method and were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), UV–vis spectroscopy and Energy Dispersive X-ray Spectroscopy (EDAX) studies. The interaction study of CuO NPs-protein was done using dynamic light scattering studies, fluorescence spectroscopy, UV–vis spectroscopy, circular dichroism technique and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The spectroscopic evaluation clarifies various features of binding through the molecular interactions of CuO NPs and serum proteins along with surfactants. Gel electrophoresis was used to study NPs-DNA interactions in the presence and absence of surfactants. Nanoparticle-protein binding was found to be strongest in CTAB, SDS and Tween 80 based systems. Tween 80 surfactant was also found to provide continual biocompatibility to CuO NPs. The study gives detail information about the effect of different surfactant coatings on CuO nanoparticle surfaces along with their effects on vital biomolecules. The findings will thus be very helpful in designing stable CuO NP formulations for biomedical applications.