Search Results (329)

Surfactants can be utilized to improve oil recovery by changing the performance of reservoirs in rock pores. Kerogen is the primary organic matter in shale; however, high temperatures will affect the overall performance of this surfactant, resulting in a decrease in its activity or even failure. The effect of surfactants on kerogen pyrolysis has rarely been researched. Therefore, this study synthesized a polymeric surfactant (PS) with high temperature resistance and investigated its effect on kerogen pyrolysis under the friction of drill bits or pipes via molecular dynamics. The infrared spectra and thermogravimetric and molecular weight curves of the PS were researched, along with its surface tension, contact angle, and oil saturation measurements. The results showed that PS had a low molecular weight, with an MW value of 124,634, and good thermal stability, with a main degradation temperature of more than 300 °C. It could drop the surface tension of water to less than 25 mN·m⁻¹ at 25–150 °C, and the use of slats enhanced its surface activity. The PS also changed the contact angles from 127.96° to 57.59° on the surface of shale cores and reversed to a water-wet state. Additionally, PS reduced the saturated oil content of the shale core by half and promoted oil desorption, indicating a good cleaning effect on the shale oil reservoir. The kerogen molecules gradually broke down into smaller molecules and produced the final products, including methane and shale oil. The main reaction area in the system was the interface between kerogen and the surfactant, and the small molecules produced on the interface diffused to both ends. The kinetics of the reaction were controlled by two processes, namely, the step-by-step cleavage process of macromolecules and the side chain cleavage to produce smaller molecules in advance. PS could not only desorb oil in the core but also promote the pyrolysis of kerogen, suggesting that it has good potential for application in shale oil exploration and development. Full article

Hydrogel particles, renowned for their high water content and biocompatibility in drug delivery and tissue engineering, typically rely on complex, costly microfluidic systems to reach sub 5 µm dimensions. We present a vortex-based inverse-emulsion polymerization strategy in which UV crosslinking of polyethylene glycol diacrylate (PEGDA) dispersed in n-hexadecane and squalene yields tunable micro- and nanogels while delineating the parameters that govern particle size and uniformity. Systematic variation in surfactant concentration, vessel volume, continuous phase viscosity, vortex speed and duration, oil-to-polymer ratio, polymer molecular weight, and pulsed vortexing revealed that increases in surfactant level, vortex intensity/duration, vessel volume, and oil-to-polymer ratio each reduced mean diameter and PDI, whereas higher polymer molecular weight and continuous phase viscosity broadened the size distribution. We further investigated how these same parameters can be tuned to shift particle populations between nano- and microscale regimes. Under optimized conditions, microhydrogels achieved a coefficient of variation of 0.26 and a PDI of 0.07, with excellent reproducibility, and nanogels measured 161 nm (PDI = 0.05). This rapid, cost-effective method enables precise and scalable control over hydrogel dimensions using only standard laboratory equipment, without specialized training. Full article

Polymeric nanoparticles based on poly(ethyl cyanoacrylate) (PECA) and poly(ε-caprolactone) (PCL) were synthesized via semicontinuous microemulsion polymerization for potential biomedical applications. A systematic evaluation of four surfactants (Tween 80, Alkonat L70, Genapol LRO, and Brij-20) was carried out to determine their effects on micelle formation and particle size. Brij-20 enabled the formation of nanoparticles under 100 nm, with optimal conditions identified at 4% surfactant concentration and pH 1.75. The polymerization process included acid-catalyzed ring-opening of ε-caprolactone, followed by the semicontinuous addition of ethyl-2-cyanoacrylate under an inert atmosphere. Copolymerization was confirmed through FT-IR spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and differential scanning calorimetry, revealing a glass transition temperature (T_g) of 110.9 °C, indicating PECA as the dominant phase. Thermogravimetric analysis showed two decomposition events corresponding to each polymer. Transmission electron microscope analysis revealed nanoparticles averaging 51.74 nm in diameter. These findings demonstrate the feasibility of producing PECA-PCL nanoparticles with controlled size and composition, suitable for drug delivery and other biomedical uses. Full article

The removal of per- and polyfluoroalkyl substances (PFAS) from global aquatic environments is an emerging issue. However, little attention has been paid to addressing accumulated PFAS through their removal. This study demonstrates the encapsulation of perfluoroalkyl carboxylic acids (PFCAs) within polymer microspheres that dissolve in supercritical carbon dioxide (scCO₂). PFCAs were effectively captured by a hindered amine-supported monomer, 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TPMA), in methanol (MeOH) through a simple acid-base reaction. The PFCA-loaded TPMA underwent dispersion polymerization in MeOH in the presence of poly(N-vinylpyrrolidone) (PVP) as a surfactant, producing microspheres with high monomer conversions. The microsphere size depended on the molecular weight and concentration of PVP, as well as the perfluoroalkyl chain length of the PFCAs. X-ray photoelectron spectroscopy (XPS) revealed that the perfluoroalkyl chains migrated from the interior to the surface of the microspheres when exposed to air. These surface perfluoroalkyl chains facilitated dissolution of the microspheres in scCO₂, with cloud points observed under relatively mild conditions. These findings suggest the potential for managing PFCA-encapsulated microspheres in the scCO₂ phase deep underground via CO₂ sequestration. Full article

Breast cancer remains a leading cause of cancer-related morbidity and mortality among women worldwide. Its treatment is complicated by molecular heterogeneity and the frequent development of multidrug resistance (MDR). Conventional drug delivery approaches are often limited by poor aqueous solubility, rapid systemic clearance, non-specific biodistribution, and off-target toxicity. This review will critically explore the possibility of surfactant-based drug delivery systems (DDSs) in addressing the constraints of standard breast cancer treatments. It focuses on the mechanisms by which surfactants promote solubility, facilitate cellular uptake, and overcome drug resistance, while also analyzing current therapeutic success and future directions. A thorough review of preclinical and clinical investigations was undertaken, focusing on important surfactant-based DDSs such as polymeric micelles, nanoemulsions, liposomes, and self-emulsifying systems (SEDDSs). Mechanistic insights into surfactant functions, such as membrane permeabilization and efflux pump inhibition, were studied alongside delivery systems incorporating ligands and co-loaded medicines. Pluronic^® micelles, TPGS-based systems, biosurfactant-stabilized nanoparticles, and lipid-based carrier surfactant platforms improve medication solubility, stability, and delivery. Genexol^® are examples of formulations demonstrating effective use and FDA translational potential. These systems now incorporate stimuli-responsive release mechanisms—such as pH, temperature, redox, immuno- and photodynamic treatment—artificial intelligence treatment design, and tailored treatment advancement, and responsive tailoring. Surfactant-enabled DDSs can improve breast cancer care. Innovative approaches for personalized oncology treatment are countered by the enduring challenges of toxicity, regulatory hurdles, and diminished scalability. Full article

Polymer flooding is one of the critical methods for enhancing oil recovery (EOR) in domestic and international oilfields. Since the large-scale implementation of industrial polymer flooding in Daqing Oilfield in 1996, the overall recovery rate has increased by over 10%. With the advancement of chemical flooding technologies, conventional polymer flooding can no longer meet the practical demands of oilfield development. This study focuses on functional polymers, such as salt-resistant polymers and polymeric surfactants, tailored for Class II and III reservoirs in Daqing Oilfield. A series of experiments, including emulsification experiments, hydrodynamic characteristic size-reservoir compatibility comparison experiments, polymer retention experiments in porous media, and core flooding experiments, were conducted to investigate the differences between functional polymers and conventional polymers in terms of intrinsic properties and application performance. Comparative analyses of molecular chemical structures and micro-aggregation morphologies between functional polymers (branched polymers and polymeric surfactants) and conventional polymers revealed structural composition disparities and distinct viscosity-enhancing properties. From the perspective of aqueous solution viscosity enhancement mechanisms, functional polymers exhibit a three-stage viscosity-enhancing mechanism: bulk viscosity, associative viscosity, and emulsion-induced viscosity enhancement. The hydrodynamic characteristic sizes of polymers were analyzed to evaluate their compatibility with reservoir pore structures, and the seepage resistance mechanisms of both polymeric surfactants and salt-resistant polymers were identified. Core flooding experiments conclusively demonstrated the superior practical performance of functional polymers over conventional polymers. The application of functional polymers in polymer flooding can effectively enhance oil recovery. Full article

In the field of water-based inks, the use of alkali-soluble resins (ASRs) as polymeric surfactants for synthesizing polyacrylate latexes has become a mainstream method. This study first designed and prepared crosslinkable ASRs with a diacetone acrylamide (DAAM) crosslinking monomer via emulsion polymerization. These ASRs were then employed as surfactants to synthesize self-crosslinking polyacrylate latexes through an in situ one-pot method, systematically investigating the influence of crosslinkable ASRs on the properties of the corresponding polyacrylate latexes. The research revealed that all prepared polyacrylate latexes exhibited a core–shell structure. With increasing DAAM content in the ASRs, the latex particle size gradually increased while the particle size distribution narrowed. All latexes demonstrated excellent stability, with absolute ζ-potential values exceeding 30 mV. The introduction of DAAM into ASRs significantly increased the glass transition temperature in the high-temperature region of the corresponding latex films, with the tensile strength reaching a maximum of 7.96 MPa. Moderate crosslinking in ASRs substantially improved the water resistance of latex films. Crosslinking degree tests indicated that latex films prepared through either single shell-layer crosslinking or single core-layer crosslinking showed relatively low crosslinking degrees, while only the dual core–shell crosslinking strategy could effectively enhance the film crosslinking degree. However, excessively crosslinked shell layers significantly hindered the crosslinking reaction of DAAM in the core layer, leading to reduced overall film crosslinking. Additionally, incorporating a certain number of DAAM crosslinking groups in ASRs was found to improve the adhesion of corresponding water-based inks on PE and BOPP substrates, with adhesion on BOPP substrates reaching up to 100%. Full article

The tomato leaf miner Phthorimaea (syn. Tuta) absoluta (Lepidoptera: Gelechiidae) is invasive in many agricultural regions. Its larvae feed inside leaf mines and tomato fruits, causing yield losses. Repeated sprays of insecticides disrupt agri-ecosystems. Conducting three open-field tomato experiments, we assessed whether formulations of entomopathogenic nematodes could improve the efficacy of these promising biocontrol agents or whether other nature-based agents such as pyrethrin or spinosad would be the better option(s), as compared to a standard insecticide. Steinernema carpocapsae formulated in an alkyl polyglycoside polymeric surfactant, in canola oil, or mixed in both reduced 37 to 68% of pest larvae within two weeks post-treatment, followed by the botanical pyrethrin (48%). Neither spinosad nor lambda cyhalothrin achieved sufficient control. Increasing the frequency of treatments to every two weeks moderately increased efficacy. Positively, the nematodes can, if properly formulated and applied, still be recovered alive from leaf surfaces up to two hours after spraying, indicating that they have time to enter the leaf mines. A small proportion can even be still extracted alive from the leaf mines one week later. Despite these promising results, further research is needed to improve the efficacy of nature-based management options for use against this pest, with the aim of ultimately reducing reliance on chemical insecticides and minimizing the impact on agri-ecosystems. Full article

Continuous human population growth, industrialization, and technical progress have increased the demand for a new design and synthesis of chemical compounds. Developing eco-friendly chemical compounds has been a priority for fostering a sustainable and healthy environment, which is directly linked to human well-being. In this context, green chemistry and circular economy principles have been applied to generate valuable new chemicals, such as surfactants, with high market value. Surfactants play a crucial role in various products for both domestic and industrial applications, leading to their large-scale production a diverse array of chemical structures. However, the advantages of their use must be balanced against their negative environmental impact as pollutants. Thus, there is an increasing demand for the development of new eco-friendly surfactants. Additionally, life cycle assessment (LCA) studies of new surfactants are essential for evaluating their environmental impact, enhancing energy efficiency and facilitating the transition toward sustainable energy resources. In this work, we present the chemical synthesis of oligomeric and polymeric thiophene-based surfactants with potential applications in biosensors, organic transistors, and various other fields. The newly synthesized oligomeric and polymeric thiophene-based surfactants demonstrated medium-to-high biodegradation potential and showed no significant ecotoxicological effects on bacterial communities. However, the LCA of their synthesis revealed a negative impact on the environment and human health, particularly concerning polymeric thiophene-based surfactants. The LCA identified specific chemical steps that could be optimized to develop a new generation of eco-friendly surfactants. Full article

The development of eco-friendly surfactants is pivotal for enhanced oil recovery (EOR). In this study, a novel lignin-derived zwitterionic surfactant (DMS) was synthesized through a two-step chemical process involving esterification and free radical polymerization, utilizing renewable alkali lignin, maleic anhydride, dimethylamino propyl methacrylamide (DMAPMA), and sulfobetaine methacrylate (SBMA) as precursors. Comprehensive characterization via ¹H NMR, FTIR, and XPS validated the successful integration of amphiphilic functionalities. Hydrophilic–lipophilic balance (HLB) analysis showed a strong tendency to form stable oil-in-water (O/W) emulsions. The experimental results showed a remarkable 91.6% viscosity reduction in Xinjiang heavy crude oil emulsions at an optimum dosage of 1000 mg/L. Notably, DMS retained an 84.8% viscosity reduction efficiency under hypersaline conditions (total dissolved solids, TDS = 200,460 mg/L), demonstrating exceptional salt tolerance. Mechanistic insights derived from zeta potential measurements and molecular dynamics simulations revealed dual functionalities: interfacial modification by DMS-induced O/W phase inversion and electrostatic repulsion (zeta potential: −30.89 mV) stabilized the emulsion while disrupting π–π interactions between asphaltenes and resins, thereby mitigating macromolecular aggregation in the oil phase. As a green, bio-based viscosity suppressor, DMS exhibits significant potential for heavy oil recovery in high-salinity reservoirs, addressing the persistent challenge of salinity-induced inefficacy in conventional chemical solutions and offering a sustainable pathway for enhanced oil recovery. Full article

Background/Objectives: Cutaneous melanoma is a potent neoplasm whose advancement is linked to catecholamine-induced angiogenesis through β-adrenergic receptors. Propranolol (PROP), a non-selective β-blocker, holds potential in oncology, but its systemic side effects restrict its viability. This study aims to nanoencapsulate PROP in Eudragit RL^®100 polymeric nanocapsules for topical melanoma treatment. Methods: Nanocapsules were created through interfacial deposition of preformed polymer and characterized in terms of particle size, zeta potential, pH, drug content, and encapsulation efficiency. In vitro evaluations include release profile, antioxidant activity, bioadhesiveness, hemolysis, cytotoxicity, and antitumor effect on melanoma cells. Additionally, migration assays were conducted. Results: The nanocapsules displayed an acidic pH, an average size of 151 nm, and a positive zeta potential. An encapsulation efficiency of 81% was achieved, even with the hydrochloride form of the drug. The release profile exhibited sustained release of PROP, showcasing enhanced antioxidant activity in the nanoencapsulated form. The formulations also exhibited significant bioadhesion with mucin and an in vitro hemolysis rate over 50%, attributed to the cationic polymer and surfactants present. Moreover, in the cell viability assays, the NC-PROP formulations significantly reduced melanoma cell viability. In the migration assay, both the nanocapsules with and without the drug significantly inhibited cell migration, supporting the potential therapeutic benefits of these formulations. Conclusions: The nanoencapsulation of PROP in Eudragit RL^®100 presents a viable strategy for topical treatment of cutaneous melanoma, enhancing release duration and reducing systemic effects. The assessments indicated distinct physical properties and substantial therapeutic potential. Full article

In this study, polymerized silicone surfactants were modified with polyether and tertiary amine groups with the aim of improving the surface performance. Various PSiEO/(PO)-OH(CH₃) surfactants were synthesized and their structures and performance were characterized through ¹H NMR, FTIR spectroscopy, static surface tension, dynamic surface tension, zeta potential, and dynamic light scattering measurements. Subsequently, the modified silicones were incorporated as surfactants in aqueous solutions with different pH values. The surfactants with different hydrophobic/hydrophilic groups and end-capping groups exhibited different surface performances over a wide pH range. Thermodynamic parameters indicated that the micellization and adsorption of these surfactants were endothermic and spontaneous processes driven by entropy. The processes were hindered by increasing the solution pH and modification with hydrophobic groups. The aggregation behavior was significantly different under acidic, neutral, and basic aqueous conditions. Full article

A group of CuAl catalysts were synthesized with a Cu/Al molar ratio of 1:1 using different preparation methods: coprecipitation, surfactant assisted coprecipitation, polymeric precursor, and self-combustion and then screened for the selective dehydration of glycerol to acetol. The catalysts were employed in glycerol conversion at the same temperature (227 °C) in two different laboratory-scale systems, the first one at atmospheric pressure (gas phase) and the second one in a pressurized system at 34 absolute bar (liquid phase). The preparation method of the CuAl catalysts influenced the carbon yield to liquids and acetol selectivity. However, the reaction phase had a greater influence than the preparation method of the catalyst. In the gas phase, the carbon yield to liquids reached values above 40% and the carbon selectivity to acetol was higher than 90%. The highest acetol yield, 462.6 mg_acetol/g_glycerol, was obtained with the CuAl catalyst prepared by the surfactant-assisted coprecipitation method. This study provides a new perspective on catalyst design by highlighting the crucial role of preparation techniques in determining CuAl catalyst performance in the liquid and gas phases. Full article

Although polyethylene glycol (PEG)-based surfactants are widely used in various industries due to their wide range of hydrophile–lipophile balance (HLB) values, their possible by-product, 1,4-dioxane, has been listed as a reasonably anticipated human carcinogen, which may limit their applications in fields closely related to the human body. Polyglycerol fatty acid esters (PGFEs), a class of surfactants based on polyglycerol (another polyether), also have a wide range of HLB values that can be adjust by varying the degree of polymerization of the polyglycerol, the length of the fatty acid carbon chain, or the degree of esterification, but do not have the risks caused by 1,4-dioxane. In addition, all the raw materials (glycerol and fatty acids) required for the preparation of PGFEs can be obtained via hydrolysis of renewable vegetable oils. Therefore, PGFEs, as new eco-friendly and biodegradable non-ionic surfactants, have been proposed as potential green alternatives to PEG-based non-ionic surfactants. This review summarizes the properties of PGFEs specifically including their HLB, surface properties, phase behaviors, stabilizing effect on foams and emulsions, and stability, and highlights their potential applications in food, cosmetics, and pharmaceuticals observed in the last decade. Full article

In this investigation, electrochemical deposition procedures were reported to synthesize a novel composite polymer, 3-methylpyrrole-dodecyl sulfate sodium/3,4-ethylenedioxythiophene (3MPY-SDS/EDOT) coatings, on OL 37 samples for anticorrosion protection. The anionic surfactant dodecyl sulfate sodium used in deposition can have a relevant action on the protective capacity. These coatings were considered by cyclic voltammetry (CV), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM) methods. The protective attributes of OL 37 coated with P3MPY-SDS/PEDOT have been examined by potentiostatic and potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) procedures in 0.5 M H₂SO₄. The corrosion rate of the P3MPY-SDS/PEDOT-coated OL 37 sample was found to be approximately nine times lower than that of the uncoated sample. The protective layers of these composites demonstrate an effectiveness of over 90%. The optimal efficiency is obtained by electrochemical deposition of P3MPY-SDS/PEDOT, performed at applied potentials of 1.0 V, 1.2 V, and 1.4 V, with current densities of 3 mA/cm² and 5 mA/cm² and a molar ratio of 5:3 at 20 min. The influence of electrochemical polymerization parameters—applied potential, current density, scan rate, cycle number, and monomer ratio—on the protective behavior of P3MPY-SDS/PEDOT layers was analyzed, identifying optimal synthesis conditions. Corrosion examinations confirmed that P3MPY-SDS/PEDOT coatings provide effective protection for OL 37 in a corrosive environment. Full article