The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and consti...The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and constitutive equation for the novel viscoelastic micelle systems were investigated.The results show that the micelle systems possess viscoelasticity,thixotropy,and shear thinning property.Some micelle systems possess hysteresis loops showing both viscoelasticity and thixotropy.It is proved that the flow curves are characterized by the co-rotational Jeffreys constitutive equation correctly.展开更多
Non-aqueous emulsions have a wide range of applications in cosmetics,drug-controlled release,and the preparation of functional nanoparticles.However,due to the weaker polarity of non-aqueous solvents,these emulsions o...Non-aqueous emulsions have a wide range of applications in cosmetics,drug-controlled release,and the preparation of functional nanoparticles.However,due to the weaker polarity of non-aqueous solvents,these emulsions often exhibit inferior stability compared to their aqueous counterparts.In this experiment,the properties of quaternary ammonium surfactants in glycerol were investigated through surface tension measurements,to further enhance the stability of n-decane/glycerol emulsions,hydrophilic nanoparticles SiO_(2) were modified in situ using double tailed quaternary ammonium surfactants Di-C_(12)DAB and Di-C_(16)DAB.Stable n-decane/glycerol Pickering emulsions were successfully prepared.These emulsions were stable at 45℃for over six months,and no significant changes in droplet size occurred.The minimum droplet size of the emulsion was only 2-3μm.Contact angle measurements showed that the wettability of the silica surface was tremendously affected by the concentration and the alkyl chain length of the double-tailed surfactants.In the presence of Di-C_(12)DAB,the contact angle of glycerol on the silica surface increased monotonically with the surfactant concentration.This explains the phenomenon that the Pickering emulsions containing Di-C_(12)DAB and silica particles were stable within the contact angle range of 80°-120°.Comparatively,the contact angle of the glycerol on the silica surface in the presence of Di-C_(16)DAB first increased with surfactant concentrations and then decreased,reaching a maximum at 0.6 mmol/L.It can be concluded that Di-C_(12)DAB formed monolayers at the surface of silica particles within all investigated concentrations.On the contrary,Di-C_(16)DAB formed monolayers at concentrations below 0.6 mmol/L and formed double layers at concentrations above 0.6 mmol/L,leading to a non-monotonic change in the contact angle with respect to concentration.Using these stable non-aqueous Pickering emulsions as templates,polymer microspheres with a particle size of 2-3μm were successfully prepared with high yield.This work is helpful to expand the potential applications of non-aqueous emulsions in the encapsulation of drug,controlled release,material preparation,and cosmetic formulations.展开更多
In order to explore the mechanism of improving the surface wettability of low-energy polytetrafluoroethylene(PTFE)by new extended surfactants,five kinds of extended anionic surfactants with different numbers of oxypro...In order to explore the mechanism of improving the surface wettability of low-energy polytetrafluoroethylene(PTFE)by new extended surfactants,five kinds of extended anionic surfactants with different numbers of oxypropylene(PO)and oxyethylene(EO),octadecyl-(PO)_(m)-(EO)_(n)-sodium carboxylate(C_(18)PO_(m)EO_(n)C,m=5,10,15,n=5,10,15),were studied.The surface tension and contact angle of C_(18)PO_(m)EO_(n)C solution with different concentrations were measured,and the adhesion tension,PTFE-water interfacial tension,and adhesion work were calculated.It was found that the extended surfactant molecules adsorb on the surface of the solution and the PTFE-liquid interface simultaneously when the concentration is lower than the critical micelle concentration(cmc),and there was a linear relationship between surface tension and adhesion tension.The adsorption amount of C_(18)PO_(m)EO_(n)C at the PTFE-water interface was significantly lower than that on the surface of the solution.As the concentration increases above cmc,semi-micelle aggregates on the surface of PTFE are formed by C_(18)PO_(m)EO_(n)C molecules through hydrophobic interaction,and the hydrophilic group faces the solution to modify the surface of PTFE with high efficiency.展开更多
Fluorosurfactants play a crucial role in ensuring the stability and uniformity of droplet microreactors,which significantly broaden their applications in chemical and biological research.This review covers structure d...Fluorosurfactants play a crucial role in ensuring the stability and uniformity of droplet microreactors,which significantly broaden their applications in chemical and biological research.This review covers structure diversity and functional versatility of fluorosurfactants.Fluorosurfactants can be divided into two basic types according to their structure,linear and dendritic types,which both provides individual advantages.Linear fluorosurfactants are easily synthesized and commercially available,whereas dendritic fluorosurfactants have a branched structure that greatly reduces molecular cross-talk between droplets.Based on the application point of view,fluorosurfactants can be further classified into two categories:reactive and responsive fluorosurfactants.The hydrophilic head of reactive fluorosurfactants contains a reactive functional group,making them very useful in other applications,such as microcapsule preparation or protein crystallization.In contrast,responsive fluorosurfactants would change their properties with respect to external stimuli,such as temperature or light,making them perfect candidates for the on-demand control of droplet behavior.Development of these new classes of fluorosurfactants has expanded the capabilities and applications of droplet microreactors that enables interdisciplinary challenges to be solved.展开更多
The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar...The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar structures based on traditional analytical techniques.We developed a high-throughput method for distinguishing various surfactants based on the adaptive emission profile as fingerprints(AEPF).The fluorescence response of the sensor was based on the interaction between surfactants and 1,3-diacetylpyrene(o-DAP)probe.The interaction affected the reversible conversion of free molecules and two aggregates in the solution,thereby changing the relative abundance and the fluorescence intensity ratio of two aggregates emitting different fluorescence.The o-DAP sensor can distinguish four types of surfactants(16 surfactants),especially surfactants of the same type with similar structures.The o-DAP sensor sensitively determined the critical micelle concentration(CMC)of 16 surfactants based on the interaction between o-DAP and surfactants.Additionally,the o-DAP sensor can detect and distinguish artificial vesicles made from different surfactants.展开更多
This paper summarizes the mechanisms and environmental effects of interactions between microplastics and surfactants: surfactants adsorb onto microplastics surfaces through hydrophobic interactions and electrostatic f...This paper summarizes the mechanisms and environmental effects of interactions between microplastics and surfactants: surfactants adsorb onto microplastics surfaces through hydrophobic interactions and electrostatic forces, changing their surface properties and transport behavior. In addition, microplastics act as carriers influencing surfactant distribution. Environmental factors (pH, ionic strength, etc. ) significantly regulate this process. Current research still has limitations in areas such as desorption kinetics and combined pollution effects, necessitating in-depth studies under environmentally relevant conditions to provide a basis for risk assessment.展开更多
Surfactants play a critical role in enhanced oil recovery(EOR) applications;however,their performance is often compromised in harsh reservoir conditions,such as high temperature and high salinity,due to precipitation ...Surfactants play a critical role in enhanced oil recovery(EOR) applications;however,their performance is often compromised in harsh reservoir conditions,such as high temperature and high salinity,due to precipitation caused by interactions with multivalent metal ions.Chelating agents were introduced into oilfields for various purposes due to their ability to sequester metal ions.In this work,we conducted a comprehensive investigation about chelating agent-surfactant(CS) flooding for carbonate reservoirs,as an alternative to the well-established alkaline surfactant(AS) flooding used in sandstone.The tested surfactants include sodium dodecyl sulfate(anionic)(SDS),dodecyltrimethylammonium bromide(cationic)(DTAB),Triton X100(nonionic),and a locally synthesized zwitterionic surfactant.The tested chelating agents include diethylenetriaminepentaacetic acid(DTPA),ethylenediaminetetraacetic acid,and glutamic acid N,N-diacetic acid.pH and temperature,as dominant factors in chelating agent solubility and brine stability,were modified to test chelating agent solutions of different concentrations and their mixtures with surfactants.Interfacial tension reduction by chelating agents alone,surfactants alone,and their mixtures were measured.Wettability alteration brought by chelating agents and surfactants on carbonate rock surfaces was evaluated using the static contact angle method.Based on the obtained results,chelating agents can be applied as low-cost additives for surfactant stabilization in high salinity conditions.The addition of chelating agents significantly improved the stability of SDS and DTAB in salt solutions and seawater.At a relatively low concentration(0.25 wt%),DTPA was able to stabilize DTAB of 1.00 wt% in seawater at high temperature(90℃).DTPA,among the tested three chelating agents,exhibited a stronger stabilization effect on surfactants of different ion types.When chelating agents are to be applied in brine,an optimal applicable pH range of 5-9 is recommended so not to induce solubility issue of chelating agents or stability issues of metal ions.In this range,IFT reduction is more significant at high pH,while wettability alteration is more significant at low pH.The combination of a cationic surfactant with a chelating agent forms a low adsorption wettability modifier which can change strongly oil-wet rock to water-wet conditions,thus significantly increasing the residual oil recovery from oil-wet carbonate formations.Zwitterionic and nonionic surfactants are also applicable to combine with a chelating agent for EOR purposes.Anionic surfactant SDS,however,showed a growing inhibition on the wettability alteration effect induced by EDTA as the concentration of SDS increased.展开更多
The effects of different kinds of cosurfactants on the properties of the crystalline amino acid cleanser based on potassium cocoyl-glycine were studied by analyzing the foam properties,high-temperature stability and c...The effects of different kinds of cosurfactants on the properties of the crystalline amino acid cleanser based on potassium cocoyl-glycine were studied by analyzing the foam properties,high-temperature stability and crystallization temperature.The results showed that PEG-80 sorbitan laurate makes the composite foaming system slower and less,but the foam stability and high-temperature stability are better.The addition of lauryl hydroxysultaine can make the foaming speed faster and the foam volume larger,and this material can improve the crystallization of potassium cocoyl-glycine,so that the high-temperature stability of the composite system is better.The addition of anionic surfactant like sodium methyl cocoyl taurate or sodium lauroyl glutamate is helpful for foam fineness and foam stability,but may have a negative effect on high-temperature stability.The addition of lauryl glucoside is disadvantage on foam stability and high-temperature stability,so it is not suitable for this system.Cosurfactants can be selected on demand when developing the related products.展开更多
Background:Traditional synthetic surfactants used in shampoos,such as sodium lauryl sulfate(SLS),raise significant environmental and dermatological concerns due to their poor biodegradability,high irritation potential...Background:Traditional synthetic surfactants used in shampoos,such as sodium lauryl sulfate(SLS),raise significant environmental and dermatological concerns due to their poor biodegradability,high irritation potential,and petrochemical origin.In contrast,biosurfactants offer eco-friendly,skin-compatible alternatives that align with green chemistry principles and support sustainable personal care.Objective:This review aims to critically evaluate the functional,environmental,and dermatological performance of microbial biosurfactants,particularly rhamnolipids and sophorolipids,as sustainable alternatives to synthetic surfactants in shampoo formulations.Methods:A comprehensive analysis of published research was conducted to assess biosurfactant properties,production methods,comparative cleansing and foaming efficacy,biodegradability,skin compatibility,and formulation challenges.The review includes physicochemical data,in vitro and in vivo performance metrics,and case examples from commercial products.Results:Rhamnolipids and sophorolipids demonstrated sebum removal efficiencies of 85–95%,foam volume retention above 75%,and biodegradability rates of 60–95%within 7–14 days.They exhibited lower irritation indices(<1.0)and caused≤10%protein loss in skin models,in contrast to SLS,which caused up to 40%protein denaturation.However,biosurfactant integration is challenged by higher costs($20–40/kg),pH sensitivity,and limited consumer familiarity.Formulation strategies such as hybrid surfactant systems,pH buffering,and synergistic blends were reviewed to overcome these barriers.Conclusion:Biosurfactants offer a promising path toward microbiome-friendly,sustainable shampoos without compromising cleansing or sensory performance.To enable broader adoption,efforts must focus on improving fermentation efficiency,optimizing formulation stability,and educating consumers.Strategic positioning of biosurfactants based on their unique functional profiles can help meet evolving demands for eco-conscious and dermatologically gentle hair care.展开更多
By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permea...By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency.展开更多
During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via revers...During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via reverse microemulsion polymerization using acrylamide,2-methyl-2-acrylamidopropane sulfonic acid,and stearyl methacrylate as monomers,with N,N-methylenebisacrylamide as the crosslinker.The microspheres were then combined with sodium alkyl alcohol polyoxyethylene ether carboxylate to enhance emulsion stability and expand the swept volume of surfactant.A stable reverse microemulsion system was prepared using the maximum water solubilization rate as the indicator,and microspheres were synthesized based on this system.The ability of the microspheres to enhance emulsion stability was systematically evaluated.The plugging performance and enhanced oil recovery(EOR)efficiency of the microsphere/surfactant composite system were assessed through core seepage and oil displacement experiments.The experimental results demonstrated that microspheres were successfully prepared in a water-in-oil reverse microemulsion system with a solubilization rate of 42%.The emulsion stability was evaluated under an oil-to-water ratio of 7:3,a temperature of 80℃,and a salinity of 44,592 mg/L,by manually shaking the test tube five times.It was observed that the complete phase separation time of the emulsion increased from 10 to 120 min after the addition of microspheres.Under different permeability conditions(100×10^(-3),300×10^(-3),500×10^(-3)μm^(2)),the recovery efficiency of the composite system increased by 4.5%,8.3%,and 4.8%,respectively,compared to a single surfactant system.The microspheres developed in this study enhanced emulsion stability and increased the swept volume of surfactant within the formation,significantly boosting its oil recovery efficiency.展开更多
As one promising CO_(2)capture,utilization and storage(CCUS)technology,miscible CO_(2)-enhanced oil recovery(CO_(2)-EOR)significantly outperforms immiscible flooding in enhancing oil production and storing CO_(2).Howe...As one promising CO_(2)capture,utilization and storage(CCUS)technology,miscible CO_(2)-enhanced oil recovery(CO_(2)-EOR)significantly outperforms immiscible flooding in enhancing oil production and storing CO_(2).However,achieving CO_(2)miscible flooding is often hindered by the high minimum miscibility pressure of CO_(2)-oil system in many reservoirs.To address this issue,this study focuses on the mechanisms for enhancing CO_(2)-oil miscibility using different types of surfactants and their blends with ethanol.The effects of fatty alcohol polyoxyethylene ethers(EO),fatty alcohol polyoxypropylene ethers(PO),tributyl citrate(TC),and glyceryl triacetate(GT)on the CO_(2)-oil miscibility pressure are quantitatively analyzed,as well as their synergy with ethanol.Results demonstrated that all tested surfactant additives reduce the CO_(2)-oil miscibility pressu re.For ethe r-based surfactant additives,an increase in the degree of polymerization(CO_(2)-philic groups)weakens the effectiveness to reduce miscibility pressure.Oxygen atoms in the functional group contribute more significantly to miscibility enhancement than carbon atoms.Among ester surfactants,GT achieved the best reduction effect of miscibility pressure(11.82%at 3.0 wt%),attributed to its symmetrical short side-chain structure and ester groups.Furthermore,ethanol exhibited a significant improvement for surfactants in enhancing miscibility.Notably,the reduction of CO_(2)-oil miscibility pressure increases to 27.9%by 3.0 wt%GT blended with 5.0 wt%ethanol.These findings demonstrate that blending surfactants with ethanol is a feasible and effective strategy to facilitate miscible CO_(2)flooding.This study provides valuable insights and practical guidance for the field implementation of miscible CO_(2)-EOR.展开更多
This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycy...This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.展开更多
Gemini quaternary ammonium salt surfactants, butane-a, co-bis(dimethyl dodeculammonium bromide) (BDDA) ethane-a, fl-bis(dimethyl dodeculammonium bromide) (EDDA) were adopted to comparatively study the flotatio...Gemini quaternary ammonium salt surfactants, butane-a, co-bis(dimethyl dodeculammonium bromide) (BDDA) ethane-a, fl-bis(dimethyl dodeculammonium bromide) (EDDA) were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory (DFT) at B3LYP/6-31G (d) level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.展开更多
[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were ...[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were studied as well as their distribution in water and soil. Effects of rationing on desorption of PCBs were also analyzed. [Result]The potential of single surfactant to enhance the desorption of PCBs from soil in order was Tween 80 SDBS HTAB. Three surfactants were largely adsorbed on soil and the sorption followed HTABTween 80SDBS. The desorption of PCBs increased significantly and linearly with the increase of aqueous micelle concentration of surfactants. [Conclusion]Enhancing effect of three surfactants on PCBs desorption were obtained,which will provide theoretical basis for further analyzing.展开更多
Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer a...Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer and X-ray powder diffraction (XRD). The results indicate that the type, dosage and relative molecular mass of surfactants significantly impact the purity, dispersion property, particle size, size distribution and morphology of the products. The nonionic surfactants poly ethylene glycol (PEG) and polyethylene glycol sorbitan monostearate (Tween) showed better dispersing ability in the reaction system than the others. The optimal mass ratios of surfactant to Ni are 100 mg/g and 150 mg/g for PEG-600 and Tween-40, respectively. The products obtained in the optimal conditions have ideal morphology and narrow size distribution. Moreover, study on the relative molecular mass effect revealed that with the increase of the relative molecular mass of Tween, the morphology of nickel powders changed from sphere to spiny ball.展开更多
Surfactants are widely used in the purification and research of structure and function of the protein complexes in photosynthetic membrane. To elucidate the mechanism of interaction between surfactants and photosystem...Surfactants are widely used in the purification and research of structure and function of the protein complexes in photosynthetic membrane. To elucidate the mechanism of interaction between surfactants and photosystem Ⅰ (PSⅠ), effects of two typical surfactants, Triton X_100 and sodium dodecyl sulfate (SDS) on PSⅠ, were studied at different concentrations. The results were: SDS led to the reduction of apparent absorption intensity and blue shift of absorption peaks; while Triton X_100 led to the decrease of apparent absorption intensity in red region and blue shift of the peak, but to the increase of apparent absorption intensity in blue region. The fourth derivative spectra show that the longwavelength (669 nm and 683 nm) absorbing chlorophyll a was affected greatly and their relative changes of absorbance were axially symmetrical. The presence of surfactant could make the long wavelength fluorescence emission decrease greatly and a new fluorescence peak appeared around 680 nm, it was obvious that the surfactant interceded the transfer of excitation energy from antenna pigments to reaction center. The surfactants might affect the microenvironment of proteins, even the structure of PSⅠ protein subunits and hence changed the binding status of pigments with protein subunits, or the pigments might be released from the subunits. All of these might affect the absorption and the transfer of excitation energy.展开更多
In order to solve the problem of poor interpretability of support vector re- gression (SVR) applied in quantitative structure-property relationship (QSPR), a com- plete set of explanatory system for SVR was establ...In order to solve the problem of poor interpretability of support vector re- gression (SVR) applied in quantitative structure-property relationship (QSPR), a com- plete set of explanatory system for SVR was established based on F-test, The nov- el explanatory system includes significance tests of model and single-descriptor im- portance, single-descriptor effect and sensitivity analysis, and significance tests of interaction between two descriptors, etc. The results of example indicated that the explanatory results of the new system were consistent well with those of stepwise linear regression model and quadratic polynomial stepwise regression model. The explanatory SVR model will play an important role in regression analysis such as QSPR.展开更多
A series of heterogemini imidazolium surfactants with two-methylene spacer groups ([Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n) have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effect...A series of heterogemini imidazolium surfactants with two-methylene spacer groups ([Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n) have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effects of various reaction parameters, including stoichiometry, reaction temperature and time, were investigated. In addition, the surface activity study about heterogemini imidazolium surfactants was carried out and the influences of dissymmetric degree on the surface properties were also discussed.展开更多
The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In...The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In this redox system, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and arabic gum were served as surfactants. The results showed that reducing agents and surfactants both act as the capping agent adhering to the certain facets of silver seeds to block this surface to grow. The relative intensity of reducing agents also takes an active part in influencing the growth rate and direction of silver seeds. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl?, Br? and I?into the aqueous and have some effects on the morphology of the nanoplates.展开更多
基金Project(20276016) supported by the National Natural Science Foundation of China
文摘The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and constitutive equation for the novel viscoelastic micelle systems were investigated.The results show that the micelle systems possess viscoelasticity,thixotropy,and shear thinning property.Some micelle systems possess hysteresis loops showing both viscoelasticity and thixotropy.It is proved that the flow curves are characterized by the co-rotational Jeffreys constitutive equation correctly.
文摘Non-aqueous emulsions have a wide range of applications in cosmetics,drug-controlled release,and the preparation of functional nanoparticles.However,due to the weaker polarity of non-aqueous solvents,these emulsions often exhibit inferior stability compared to their aqueous counterparts.In this experiment,the properties of quaternary ammonium surfactants in glycerol were investigated through surface tension measurements,to further enhance the stability of n-decane/glycerol emulsions,hydrophilic nanoparticles SiO_(2) were modified in situ using double tailed quaternary ammonium surfactants Di-C_(12)DAB and Di-C_(16)DAB.Stable n-decane/glycerol Pickering emulsions were successfully prepared.These emulsions were stable at 45℃for over six months,and no significant changes in droplet size occurred.The minimum droplet size of the emulsion was only 2-3μm.Contact angle measurements showed that the wettability of the silica surface was tremendously affected by the concentration and the alkyl chain length of the double-tailed surfactants.In the presence of Di-C_(12)DAB,the contact angle of glycerol on the silica surface increased monotonically with the surfactant concentration.This explains the phenomenon that the Pickering emulsions containing Di-C_(12)DAB and silica particles were stable within the contact angle range of 80°-120°.Comparatively,the contact angle of the glycerol on the silica surface in the presence of Di-C_(16)DAB first increased with surfactant concentrations and then decreased,reaching a maximum at 0.6 mmol/L.It can be concluded that Di-C_(12)DAB formed monolayers at the surface of silica particles within all investigated concentrations.On the contrary,Di-C_(16)DAB formed monolayers at concentrations below 0.6 mmol/L and formed double layers at concentrations above 0.6 mmol/L,leading to a non-monotonic change in the contact angle with respect to concentration.Using these stable non-aqueous Pickering emulsions as templates,polymer microspheres with a particle size of 2-3μm were successfully prepared with high yield.This work is helpful to expand the potential applications of non-aqueous emulsions in the encapsulation of drug,controlled release,material preparation,and cosmetic formulations.
文摘In order to explore the mechanism of improving the surface wettability of low-energy polytetrafluoroethylene(PTFE)by new extended surfactants,five kinds of extended anionic surfactants with different numbers of oxypropylene(PO)and oxyethylene(EO),octadecyl-(PO)_(m)-(EO)_(n)-sodium carboxylate(C_(18)PO_(m)EO_(n)C,m=5,10,15,n=5,10,15),were studied.The surface tension and contact angle of C_(18)PO_(m)EO_(n)C solution with different concentrations were measured,and the adhesion tension,PTFE-water interfacial tension,and adhesion work were calculated.It was found that the extended surfactant molecules adsorb on the surface of the solution and the PTFE-liquid interface simultaneously when the concentration is lower than the critical micelle concentration(cmc),and there was a linear relationship between surface tension and adhesion tension.The adsorption amount of C_(18)PO_(m)EO_(n)C at the PTFE-water interface was significantly lower than that on the surface of the solution.As the concentration increases above cmc,semi-micelle aggregates on the surface of PTFE are formed by C_(18)PO_(m)EO_(n)C molecules through hydrophobic interaction,and the hydrophilic group faces the solution to modify the surface of PTFE with high efficiency.
基金support of the National Key Research and Development Program of China(2021YFC2104300)the National Natural Science Foundation of China(T2322011,22308146,22278214)the support of the State Key Laboratory of Materials-Oriented Chemical Engineering(SKL-MCE-22A06,KL20-02).
文摘Fluorosurfactants play a crucial role in ensuring the stability and uniformity of droplet microreactors,which significantly broaden their applications in chemical and biological research.This review covers structure diversity and functional versatility of fluorosurfactants.Fluorosurfactants can be divided into two basic types according to their structure,linear and dendritic types,which both provides individual advantages.Linear fluorosurfactants are easily synthesized and commercially available,whereas dendritic fluorosurfactants have a branched structure that greatly reduces molecular cross-talk between droplets.Based on the application point of view,fluorosurfactants can be further classified into two categories:reactive and responsive fluorosurfactants.The hydrophilic head of reactive fluorosurfactants contains a reactive functional group,making them very useful in other applications,such as microcapsule preparation or protein crystallization.In contrast,responsive fluorosurfactants would change their properties with respect to external stimuli,such as temperature or light,making them perfect candidates for the on-demand control of droplet behavior.Development of these new classes of fluorosurfactants has expanded the capabilities and applications of droplet microreactors that enables interdisciplinary challenges to be solved.
基金supported by the National Natural Science Foundation of China(Nos.22225806,22078314,22278394,22378385)Dalian Institute of Chemical Physics(Nos.DICPI202142,DICPI202436).
文摘The overuse of surfactants has made them well-known environmental pollutants.So far,it is still a challenge to simultaneously distinguish cationic,anionic,zwitterionic,nonionic surfactants and surfactants with similar structures based on traditional analytical techniques.We developed a high-throughput method for distinguishing various surfactants based on the adaptive emission profile as fingerprints(AEPF).The fluorescence response of the sensor was based on the interaction between surfactants and 1,3-diacetylpyrene(o-DAP)probe.The interaction affected the reversible conversion of free molecules and two aggregates in the solution,thereby changing the relative abundance and the fluorescence intensity ratio of two aggregates emitting different fluorescence.The o-DAP sensor can distinguish four types of surfactants(16 surfactants),especially surfactants of the same type with similar structures.The o-DAP sensor sensitively determined the critical micelle concentration(CMC)of 16 surfactants based on the interaction between o-DAP and surfactants.Additionally,the o-DAP sensor can detect and distinguish artificial vesicles made from different surfactants.
基金Supported by Zhaoqing University Innovation and Entrepreneurship Training Program for College Students (X202410580130).
文摘This paper summarizes the mechanisms and environmental effects of interactions between microplastics and surfactants: surfactants adsorb onto microplastics surfaces through hydrophobic interactions and electrostatic forces, changing their surface properties and transport behavior. In addition, microplastics act as carriers influencing surfactant distribution. Environmental factors (pH, ionic strength, etc. ) significantly regulate this process. Current research still has limitations in areas such as desorption kinetics and combined pollution effects, necessitating in-depth studies under environmentally relevant conditions to provide a basis for risk assessment.
基金supported by the College of Petroleum Engineering&Geoscience (CPG) at King Fahd University of Petroleum and Minerals (KFUPM)。
文摘Surfactants play a critical role in enhanced oil recovery(EOR) applications;however,their performance is often compromised in harsh reservoir conditions,such as high temperature and high salinity,due to precipitation caused by interactions with multivalent metal ions.Chelating agents were introduced into oilfields for various purposes due to their ability to sequester metal ions.In this work,we conducted a comprehensive investigation about chelating agent-surfactant(CS) flooding for carbonate reservoirs,as an alternative to the well-established alkaline surfactant(AS) flooding used in sandstone.The tested surfactants include sodium dodecyl sulfate(anionic)(SDS),dodecyltrimethylammonium bromide(cationic)(DTAB),Triton X100(nonionic),and a locally synthesized zwitterionic surfactant.The tested chelating agents include diethylenetriaminepentaacetic acid(DTPA),ethylenediaminetetraacetic acid,and glutamic acid N,N-diacetic acid.pH and temperature,as dominant factors in chelating agent solubility and brine stability,were modified to test chelating agent solutions of different concentrations and their mixtures with surfactants.Interfacial tension reduction by chelating agents alone,surfactants alone,and their mixtures were measured.Wettability alteration brought by chelating agents and surfactants on carbonate rock surfaces was evaluated using the static contact angle method.Based on the obtained results,chelating agents can be applied as low-cost additives for surfactant stabilization in high salinity conditions.The addition of chelating agents significantly improved the stability of SDS and DTAB in salt solutions and seawater.At a relatively low concentration(0.25 wt%),DTPA was able to stabilize DTAB of 1.00 wt% in seawater at high temperature(90℃).DTPA,among the tested three chelating agents,exhibited a stronger stabilization effect on surfactants of different ion types.When chelating agents are to be applied in brine,an optimal applicable pH range of 5-9 is recommended so not to induce solubility issue of chelating agents or stability issues of metal ions.In this range,IFT reduction is more significant at high pH,while wettability alteration is more significant at low pH.The combination of a cationic surfactant with a chelating agent forms a low adsorption wettability modifier which can change strongly oil-wet rock to water-wet conditions,thus significantly increasing the residual oil recovery from oil-wet carbonate formations.Zwitterionic and nonionic surfactants are also applicable to combine with a chelating agent for EOR purposes.Anionic surfactant SDS,however,showed a growing inhibition on the wettability alteration effect induced by EDTA as the concentration of SDS increased.
文摘The effects of different kinds of cosurfactants on the properties of the crystalline amino acid cleanser based on potassium cocoyl-glycine were studied by analyzing the foam properties,high-temperature stability and crystallization temperature.The results showed that PEG-80 sorbitan laurate makes the composite foaming system slower and less,but the foam stability and high-temperature stability are better.The addition of lauryl hydroxysultaine can make the foaming speed faster and the foam volume larger,and this material can improve the crystallization of potassium cocoyl-glycine,so that the high-temperature stability of the composite system is better.The addition of anionic surfactant like sodium methyl cocoyl taurate or sodium lauroyl glutamate is helpful for foam fineness and foam stability,but may have a negative effect on high-temperature stability.The addition of lauryl glucoside is disadvantage on foam stability and high-temperature stability,so it is not suitable for this system.Cosurfactants can be selected on demand when developing the related products.
文摘Background:Traditional synthetic surfactants used in shampoos,such as sodium lauryl sulfate(SLS),raise significant environmental and dermatological concerns due to their poor biodegradability,high irritation potential,and petrochemical origin.In contrast,biosurfactants offer eco-friendly,skin-compatible alternatives that align with green chemistry principles and support sustainable personal care.Objective:This review aims to critically evaluate the functional,environmental,and dermatological performance of microbial biosurfactants,particularly rhamnolipids and sophorolipids,as sustainable alternatives to synthetic surfactants in shampoo formulations.Methods:A comprehensive analysis of published research was conducted to assess biosurfactant properties,production methods,comparative cleansing and foaming efficacy,biodegradability,skin compatibility,and formulation challenges.The review includes physicochemical data,in vitro and in vivo performance metrics,and case examples from commercial products.Results:Rhamnolipids and sophorolipids demonstrated sebum removal efficiencies of 85–95%,foam volume retention above 75%,and biodegradability rates of 60–95%within 7–14 days.They exhibited lower irritation indices(<1.0)and caused≤10%protein loss in skin models,in contrast to SLS,which caused up to 40%protein denaturation.However,biosurfactant integration is challenged by higher costs($20–40/kg),pH sensitivity,and limited consumer familiarity.Formulation strategies such as hybrid surfactant systems,pH buffering,and synergistic blends were reviewed to overcome these barriers.Conclusion:Biosurfactants offer a promising path toward microbiome-friendly,sustainable shampoos without compromising cleansing or sensory performance.To enable broader adoption,efforts must focus on improving fermentation efficiency,optimizing formulation stability,and educating consumers.Strategic positioning of biosurfactants based on their unique functional profiles can help meet evolving demands for eco-conscious and dermatologically gentle hair care.
文摘By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency.
基金supported by the Natural Science Foundation of Shandong Province(ZR2021ME007)the National Natural Science Foundation in China(51574267)the Key Projects of China National Key Research and Development Plan(2019YFA0708703)。
文摘During oil displacement,surfactants often encounter challenges such as emulsion instability and channeling,which can compromise their efficiency.To address these issues,polymer microspheres were synthesized via reverse microemulsion polymerization using acrylamide,2-methyl-2-acrylamidopropane sulfonic acid,and stearyl methacrylate as monomers,with N,N-methylenebisacrylamide as the crosslinker.The microspheres were then combined with sodium alkyl alcohol polyoxyethylene ether carboxylate to enhance emulsion stability and expand the swept volume of surfactant.A stable reverse microemulsion system was prepared using the maximum water solubilization rate as the indicator,and microspheres were synthesized based on this system.The ability of the microspheres to enhance emulsion stability was systematically evaluated.The plugging performance and enhanced oil recovery(EOR)efficiency of the microsphere/surfactant composite system were assessed through core seepage and oil displacement experiments.The experimental results demonstrated that microspheres were successfully prepared in a water-in-oil reverse microemulsion system with a solubilization rate of 42%.The emulsion stability was evaluated under an oil-to-water ratio of 7:3,a temperature of 80℃,and a salinity of 44,592 mg/L,by manually shaking the test tube five times.It was observed that the complete phase separation time of the emulsion increased from 10 to 120 min after the addition of microspheres.Under different permeability conditions(100×10^(-3),300×10^(-3),500×10^(-3)μm^(2)),the recovery efficiency of the composite system increased by 4.5%,8.3%,and 4.8%,respectively,compared to a single surfactant system.The microspheres developed in this study enhanced emulsion stability and increased the swept volume of surfactant within the formation,significantly boosting its oil recovery efficiency.
基金supported by the National Natural Science Foundation of China(52374063,52204065 and 52304098)the Shandong Provincial Natural Science Foundation(ZR2023ME049)+2 种基金the Fundamental Research Funds for the Central Universities(25CX07004A)State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering(SDGZK2429)Shenzhen Science and Technology Program(JCYJ20220818095605012)。
文摘As one promising CO_(2)capture,utilization and storage(CCUS)technology,miscible CO_(2)-enhanced oil recovery(CO_(2)-EOR)significantly outperforms immiscible flooding in enhancing oil production and storing CO_(2).However,achieving CO_(2)miscible flooding is often hindered by the high minimum miscibility pressure of CO_(2)-oil system in many reservoirs.To address this issue,this study focuses on the mechanisms for enhancing CO_(2)-oil miscibility using different types of surfactants and their blends with ethanol.The effects of fatty alcohol polyoxyethylene ethers(EO),fatty alcohol polyoxypropylene ethers(PO),tributyl citrate(TC),and glyceryl triacetate(GT)on the CO_(2)-oil miscibility pressure are quantitatively analyzed,as well as their synergy with ethanol.Results demonstrated that all tested surfactant additives reduce the CO_(2)-oil miscibility pressu re.For ethe r-based surfactant additives,an increase in the degree of polymerization(CO_(2)-philic groups)weakens the effectiveness to reduce miscibility pressure.Oxygen atoms in the functional group contribute more significantly to miscibility enhancement than carbon atoms.Among ester surfactants,GT achieved the best reduction effect of miscibility pressure(11.82%at 3.0 wt%),attributed to its symmetrical short side-chain structure and ester groups.Furthermore,ethanol exhibited a significant improvement for surfactants in enhancing miscibility.Notably,the reduction of CO_(2)-oil miscibility pressure increases to 27.9%by 3.0 wt%GT blended with 5.0 wt%ethanol.These findings demonstrate that blending surfactants with ethanol is a feasible and effective strategy to facilitate miscible CO_(2)flooding.This study provides valuable insights and practical guidance for the field implementation of miscible CO_(2)-EOR.
基金the Department of Science and Technology(DST),Govt.of India for providing funds under the FIST program and PURSE grant vide No.SR/PURSE/2020/31 to the department of Chemistry,University of Kashmir.
文摘This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.
基金Project(2013AA064102)supported by the High-tech Research and Development Program of ChinaProject(51004114)supported by the National Natural Science Foundation of China+1 种基金Project(2007B52)supported by the Foundation for the Author of National Excellent Doctoral Dissertation of ChinaProject(NCEP-08-0568)supported by the Program for New Century Excellent Talents in Chinese University
文摘Gemini quaternary ammonium salt surfactants, butane-a, co-bis(dimethyl dodeculammonium bromide) (BDDA) ethane-a, fl-bis(dimethyl dodeculammonium bromide) (EDDA) were adopted to comparatively study the flotation behaviors of kaolinite, pyrophyllite and illite. It was found that three silicate minerals all exhibited good floatability with Gemini cationic surfactants as collectors over a wide pH range, while BDDA showed a stronger collecting power than EDDA. FTIR spectra and zeta potential analysis indicated that the mechanism of adsorption of Gemini collector molecules on three silicate minerals surfaces was almost identical for the electronic attraction and hydrogen bonds effect. The theoretically obtained results of density functional theory (DFT) at B3LYP/6-31G (d) level demonstrated the stronger collecting power of BDDA presented in the floatation test and zeta potential measurement.
基金Supported by the National Natural Science Fund (20947003)~~
文摘[Objective]The aim of this paper was to provide theoretical basis for study on enhancement of surfactants to desorption of PCBs from soil. [Method]The desorption effects of surfactants SDBs,Tween 80,HTAB on PCBs were studied as well as their distribution in water and soil. Effects of rationing on desorption of PCBs were also analyzed. [Result]The potential of single surfactant to enhance the desorption of PCBs from soil in order was Tween 80 SDBS HTAB. Three surfactants were largely adsorbed on soil and the sorption followed HTABTween 80SDBS. The desorption of PCBs increased significantly and linearly with the increase of aqueous micelle concentration of surfactants. [Conclusion]Enhancing effect of three surfactants on PCBs desorption were obtained,which will provide theoretical basis for further analyzing.
基金Projects(51074096,51274130)supported by the National Natural Science Foundation of China
文摘Fine face-centered cubic (FCC) nickel powders were synthesized by liquid phase reduction with different surfactants. The products were investigated by scanning electron microscopy (SEM), laser particle size analyzer and X-ray powder diffraction (XRD). The results indicate that the type, dosage and relative molecular mass of surfactants significantly impact the purity, dispersion property, particle size, size distribution and morphology of the products. The nonionic surfactants poly ethylene glycol (PEG) and polyethylene glycol sorbitan monostearate (Tween) showed better dispersing ability in the reaction system than the others. The optimal mass ratios of surfactant to Ni are 100 mg/g and 150 mg/g for PEG-600 and Tween-40, respectively. The products obtained in the optimal conditions have ideal morphology and narrow size distribution. Moreover, study on the relative molecular mass effect revealed that with the increase of the relative molecular mass of Tween, the morphology of nickel powders changed from sphere to spiny ball.
文摘Surfactants are widely used in the purification and research of structure and function of the protein complexes in photosynthetic membrane. To elucidate the mechanism of interaction between surfactants and photosystem Ⅰ (PSⅠ), effects of two typical surfactants, Triton X_100 and sodium dodecyl sulfate (SDS) on PSⅠ, were studied at different concentrations. The results were: SDS led to the reduction of apparent absorption intensity and blue shift of absorption peaks; while Triton X_100 led to the decrease of apparent absorption intensity in red region and blue shift of the peak, but to the increase of apparent absorption intensity in blue region. The fourth derivative spectra show that the longwavelength (669 nm and 683 nm) absorbing chlorophyll a was affected greatly and their relative changes of absorbance were axially symmetrical. The presence of surfactant could make the long wavelength fluorescence emission decrease greatly and a new fluorescence peak appeared around 680 nm, it was obvious that the surfactant interceded the transfer of excitation energy from antenna pigments to reaction center. The surfactants might affect the microenvironment of proteins, even the structure of PSⅠ protein subunits and hence changed the binding status of pigments with protein subunits, or the pigments might be released from the subunits. All of these might affect the absorption and the transfer of excitation energy.
基金Supported by Industrialization Cultivation Projects in Colleges and Universities of Hunan Province(13CY030)Natural Science Foundation of Hunan Province(12JJ6026)Colleges and Universities Open Innovation Platform Fund of Hunan Province(14K053,15K066)~~
文摘In order to solve the problem of poor interpretability of support vector re- gression (SVR) applied in quantitative structure-property relationship (QSPR), a com- plete set of explanatory system for SVR was established based on F-test, The nov- el explanatory system includes significance tests of model and single-descriptor im- portance, single-descriptor effect and sensitivity analysis, and significance tests of interaction between two descriptors, etc. The results of example indicated that the explanatory results of the new system were consistent well with those of stepwise linear regression model and quadratic polynomial stepwise regression model. The explanatory SVR model will play an important role in regression analysis such as QSPR.
文摘A series of heterogemini imidazolium surfactants with two-methylene spacer groups ([Cm- 2-Cnim]Br2, m, n=8, 10, 12, 14, 16; m≠n) have been synthesized and characterized by 1H NMR and ESI-MS spectroscopy. The effects of various reaction parameters, including stoichiometry, reaction temperature and time, were investigated. In addition, the surface activity study about heterogemini imidazolium surfactants was carried out and the influences of dissymmetric degree on the surface properties were also discussed.
基金Project(51373097)supported by The National Natural Science Foundation of China
文摘The effect of reducing agents and surfactants on controlling the silver nanoplates was studied. Two reducing agents, trisodium citrate dehydrate (TSC) and potassium tartrate, were used to reduce the AgNO3 solution. In this redox system, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate (SDS) and arabic gum were served as surfactants. The results showed that reducing agents and surfactants both act as the capping agent adhering to the certain facets of silver seeds to block this surface to grow. The relative intensity of reducing agents also takes an active part in influencing the growth rate and direction of silver seeds. It was also found that halides can accelerate the speed of Ostwald ripening by adding Cl?, Br? and I?into the aqueous and have some effects on the morphology of the nanoplates.