Preparation and surface active properties of terminal amide type of alcohol ethoxylates

Three kinds of title amide compounds with different terminal structures (N-unsubstituted amide, N,N-dimethylamide and acylmorpholine) were prepared from alkyl tetra(oxyethylene) monoethers (alkyl: decyl or dodecyl). The cloud points of the N,N-dimethylamides and acylmorpholines were higher than the other corresponding alcohol ethoxylate derivatives previously developed by us, and all these amides inclusive of N-unsubstituted amides had sufficient hydrophilicity. Surface active properties (CMC, γ_CMC and foaming properties) of these amides in pure water and in hard water (1000 ppm of total hardness as CaCO₃) were almost the same and considered excellent as nonionic surfactants. Furthermore, they showed good lime-soap dispersing ability.     

Soap-based detergent formulations: XV. Amino esters of α-sulfo fatty acids

Amphoteric surfactants were prepared either by direct esterification of α-sulfo fatty acids with various alkanolamines or by rearrangement of the corresponding alkanolamides of the α-sulfo fatty acids to the amino esters with the aid of aqueous hydrochloric acid. The α-sulfo fatty acid monoesters of diethanolamine could be prepared only via the rearrangement method. The amino esters in the C₁₆−C₁₈ range possessed limited water solubility whereas α-sulfolaurate esters were soluble at room temperature. The amino esters were found to be stable to acid hydrolysis; however, they were generally not stable to alkali, by which they were either hydrolyzed or rearranged to the corresponding amide. Only the esters of isopropanolamine and diglycolamine were stable to alkali. Surface active properties of the esters were determined. The lime soap dispersant requirements of the compounds were slightly poorer than those of the corresponding amides. The compounds were good cotton detergents by themselves as well as in combination with soap and a silicate builder. The overall surface active properties of the amino esters were greatly inferior to those of the sulfobetaines previously reported. This indicates that an effective amphoteric lime soap dispersant should have its anionic group located at the very end of the molecule and the cationic group somewhat farther away, instead of the reverse. Presented at the AOCS Meeting, Philadelphia, September 1974.     

Surface Properties of an Alcohol Alkoxylate in the Presence of a Cationic Surfactant

Alcohol alkoxylate was prepared via propoxylation of an industrial alcohol ethoxylate. The chemical structure of the prepared compound was confirmed using FT-IR and the physical properties were evaluated by the usual methods according to ASTM. The surface properties of the aqueous solution of alcohol alkoxylate were determined with or without addition of a cationic surfactant in comparison to the corresponding alcohol ethoxylate. The measured parameters were surface tension, CMC, maximum surface excess, minimum surface area and the interaction parameter (β). These data indicate that surface properties changed due to the attractive complex formation in the mixed system.     

Preparation and Surface Activities of Modified Soy Protein–Dextrin Surfactants

A series of polymeric surfactants has been prepared through the reaction of soy protein with polyethoxylated stearyl ethers of various hydrophilic chain lengths. These surfactants exhibited surface activity, evaluated using surface tension, foaming, and wetting power that was superior to that of traditional surfactants containing only one hydrophobic moiety and one hydrophilic head group. Changing the ethoxylate (EO) group length had a significant effect on the surface activity. Increasing the EO group length decreased the critical micelle concentration (CMC) and increased the surface tension at the CMC (γ_CMC). The good surface properties of these polysaccharide/protein‐type surfactants suggest that they could be used as emulsifiers to prepare oil‐in‐water emulsions displaying good stability.     

Effect of Selected Nonionic Surfactants on the Activated Sludge Morphology and Activity in a Batch System

In this study, two nonionic surfactants, one alcohol ethoxylate (AE) and one alkylphenol ethoxylate (APE) were investigated with regard to their influence on the morphology of activated sludge flocs, microbial activity and wastewater treatment efficiency in a laboratory batch system. The experiments were carried out for a range of nonionic surfactants concentrations in wastewater from 5 to 500 mg L⁻¹. Additionally, these results were compared to the data obtained in previous experiments on anionics and performed under the same conditions. Both nonionics tested caused a decrease in the size of activated sludge flocs but they did not affect the shape of the flocs. The circularity index and convexity of flocs remained similar to the control run, containing no surfactant. The presence of nonionic surfactants within the tested concentrations range caused a decrease in biomass activity. In spite of morphological changes of activated sludge flocs and a decrease in microbial activity, only higher concentrations of nonionics in wastewater starting with the level of 50 mg L⁻¹ can induce pinpoint flocs and decrease wastewater treatment efficiency. APE showed a stronger impact on the decrease in floc size and microbial activity than alcohol ethoxylate did. APE was also more difficult to biodegrade than AE. Comparing the efficiency of wastewater treatment (in terms of COD removal) in the presence of nonionic and anionic surfactants at the same concentration of 50 mg L⁻¹, the degree of organic pollutant removal was found to be higher by about 10% for anionics than for nonionics.

Preparation and surface active properties of amphipathic compounds with two sulfate groups and two lipophilic alkyl chains

These compounds with various connecting groups between the two lipophilic groups were prepared by the reaction of glycol diglycidyl ethers with long-chain alcohols, followed by sulfation with chlorosulfonic acid or with a mixture of chlorosulfonic acid and acetic acid. The Krafft point of all these new amphipathic compounds was below 0°C, and they had good water solubility. These compounds were superior in surface active properties to general anionic surfactants with one lipophilic chain and one hydrophilic group, such as sodium dodecylsulfate. The effect of the structure of the connecting group on CMC, γ_CMC, foaming properties and wetting ability was investigated. They also showed excellent lime-soap dispersing ability.     

Potential of Vitamin B6 Dioxime Analogues to Act as Cholinesterase Ligands

Seven pyridoxal dioxime quaternary salts (1–7) were synthesized with the aim of studying their interactions with human acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The synthesis was achieved by the quaternization of pyridoxal monooxime with substituted 2-bromoacetophenone oximes (phenacyl bromide oximes). All compounds, prepared in good yields (43–76%) and characterized by 1D and 2D NMR spectroscopy, were evaluated as reversible inhibitors of cholinesterase and/or reactivators of enzymes inhibited by toxic organophosphorus compounds. Their potency was compared with that of their monooxime analogues and medically approved oxime HI-6. The obtained pyridoxal dioximes were relatively weak inhibitors for both enzymes (K_i = 100–400 µM). The second oxime group in the structure did not improve the binding compared to the monooxime analogues. The same was observed for reactivation of VX-, tabun-, and paraoxon-inhibited AChE and BChE, where no significant efficiency burst was noted. In silico analysis and molecular docking studies connected the kinetic data to the structural features of the tested compound, showing that the low binding affinity and reactivation efficacy may be a consequence of a bulk structure hindering important reactive groups. The tested dioximes were non-toxic to human neuroblastoma cells (SH-SY5Y) and human embryonal kidney cells (HEK293).     

Phase behavior and detergency study of lauryl alcohol ethoxylates with high ethylene oxide content

Nonionic surfactants such as fatty alcohol ethoxylates have been extensively used in many detergent applications, because of their high calcium ion tolerance, low critical micelle concentrations, and mildness. Although ethoxylates containing high ethylene oxide (EO) content (EO>10 moles) score higher than their low-FO counterparts on many of these desired properties, they have not been studied adequately in the context of detergency, primarily because their cloud points (CP) are higher than normal wash temperatures, typically >100°C, and thus cannot be measured. However, once the CP are manipulated appropriately using salting-out electrolytes, these surfactants can offer certain distinct advantages in terms of their molecular and phase structure. We have studied the phase structure and clouding behavior of tetradecyl ethylene-oxide mono dodecyl alcohol (C₁₂EO₁₄), a broad-range ethoxylate, as a function of the concentrations of various electrolytes. We found that, beyond a certain critical concentration, the CP decreases monotonically with increasing salt concentration. For sodium salts of various anions, the CP depression is inversely proportional to the lyotropic number of the anion. Similarly, for chloride salts of various cations, CP depression is inversely proporitional to the lyotropic number of the cation However, the effect of changing anion is stronger than that of changing cation. A micrograph of a water penetration scan at room temperature indicates the presence of isotropic L₁; hexagonal, isotropic L₂; and solid phases with increasing surfactant concentration. As is the case with low-FO nonionics, a maximum in detergency of model oily soils was found to correlate well with the minimum in oil/water interfacial tension when plotted vs. temperature. Ross Miles foam height increases with increasing concentration of salt.     

Die Emulgierung oxidierter Polyäthylen-Wachse mit ionisch - nichtionischen Emulgator-Systemen II

Emulsification of Oxidized Polyethylene Waxes with Ionic-Nonionic Emulsifier Systems II Studies using methods described earlier were extended to emulsification of oxidized polyethylene waxes having varying acid values and molecular weights with nonionic-ionic emulsifier systems. Besides nonylphenolethoxylates C_9/11- and C_13/15-fatty alcohol ethoxylates were also used in the presence of various amines as emulsifiers. The optimum degree of ethoxylation for each emulsifier was determined within each class of ethoxylate as a function of the degree of oxidation of polyethylene waxes. The efficiency of various classes of ethoxylation products and the influence of various amines were compared under different conditions.     

A double label radiotracer approach to detergency studies

The comparative detergency of a series of built detergents of commercial interest has been measured via the use of a doubly labeled multicomponent synthetic soil. Four test fabrics: cotton, nylon, Dacron, and Dacron/cotton were soiled with the seven-component soil, which was in turn almost completely and then individually labeled. The fabrics were washed in a conventional Tergotometer under cold-water and hot-water conditions. Analyses of the fabrics before and after washing were made by liquid scintillation counting. Two sets of experiments were run, the first based on cold-water detergent formulation (heavy-duty liquid), the second based on hot-water detergent formulation (heavy-duty powder). A number of nonionic surfactants were compared with linear alkyl aryl sulfonate in the first set, and two anionics were compared with two nonionics in the second set. Expressing results as total detergency, i.e., amount of soil removed from all four fabrics, it was found that, under cold-water conditions, LAS (average side chain C₁₃) is significantly less effective than the nonionics investigated. The linear primary alcohol (C₁₂-C₁₅ and C₁₄-C₁₅) ethoxylates removed slightly more soil than the ethoxylates of a Ziegler alcohol (C₁₄, C₁₆, C₁₈) and random secondary alcohols (C₁₁-C₁₅). The same tabulation for the heavy-duty powder formulations under hot-water conditions showed LAS to be least effective over-all, sulfated linear primary alcohol somewhat more effective, and ethoxylated linear, primary alcohol slightly more effective still. Redeposition of the various soil components onto unsoiled cotton was found to be slight, ranging from 0.2% to 1.7% of the amount in the wash water. Presented at the AOCS Meeting, Philadelphia, October 1966. US Testing Service, Hoboken, N. J.     

Hydroxy Sulfonated Fatty Acid Esters as Surface Active Agents VI: Ester and Amide Derivative Surfactants

Maleic acid derivatives of hydroxy sulfonated fatty acid esters were prepared by heating the lauric acid salt of 1-chloro-2-hydroxypropane-3-sulfonic acid (NaCHPS) with maleic anhydride under reflux. The surfactants thus obtained exhibited superior foaming and wettability to initial detergents that were prepared from lauric acid. Amide derivatives of lauric surfactants were prepared by reacting sodium salt of lauric acid amide with NaCHPS under reflux, in the presence of cello-solve and xylene. In acidic medium these amide derivatives possess better foaming properties and wettability than the initial detergents.     

Optimization of nonionic surfactants for hard-surface cleaning

The hard-surface cleaning performance of various nonionic homologs was evaluated as a function of carbon chain length, ethylene oxide (EO) content, blending and concentration. Results show carbon chain length to be very important to hard-surface cleaning. Performance significantly increases as carbon-chain length decreases, probably as a result of an increase in solvency properties as carbon chain length is decreased. EO content is also important, particularly if nonionics with longer carbon chain lengths are used. Surfactant concentration (dilution) has little effect on the optimum ethylene oxide content but significantly affects the optimum carbon chain length of the hydrophobe. With 5% homolog solutions, the optimally performing nonionic contains a C6 hydrophobe, but with 0.2% solutions, the optimal carbon chain length is shifted to the C8–C10 range. This is thought to result from a trade-off between the surfactant and solvent properties of the nonionic. Overall results show the optimal nonionic for hard-surface cleaning to consist of a blend of C6, C8 and C10 alcohols ethoxylated to a 50% EO level. Commonly used surfactant systems, e.g., alkylphenol ethoxylates and alkylphenol ethoxylate (APE)-butyl cellosolve (BC) blends, were also examined. Results show that alkylphenol ethoxylates give relatively poor performance compared with lower molecular weight linear nonionics because of the large size of their hydrophobe. Under concentrated use, a synergism does exist between APE and BC, but under dilute conditions, the addition of BC is ineffective. BC does not help the performance of low molecular weight nonionics. Surfactant-soil diffusion studies indicate that surfactant penetration of the soil may be the primary mechanism involved in the hard-surface cleaning of solid soils. Presented May 10, 1983, at the 74th Annual Meeting of the AOCS, Chicago, IL.     

Oximes: Inhibitors of Human Recombinant Acetylcholinesterase. A Structure-Activity Relationship (SAR) Study

Acetylcholinesterase (AChE) reactivators were developed for the treatment of organophosphate intoxication. Standard care involves the use of anticonvulsants (e.g., diazepam), parasympatolytics (e.g., atropine) and oximes that restore AChE activity. However, oximes also bind to the active site of AChE, simultaneously acting as reversible inhibitors. The goal of the present study is to determine how oxime structure influences the inhibition of human recombinant AChE (hrAChE). Therefore, 24 structurally different oximes were tested and the results compared to the previous eel AChE (EeAChE) experiments. Structural factors that were tested included the number of pyridinium rings, the length and structural features of the linker, and the number and position of the oxime group on the pyridinium ring.     

Synergism and Performance Optimization in Liquid Detergents Containing Binary Mixtures of Anionic–Nonionic, and Anionic–Cationic Surfactants

In this paper evaluation of surface active and application properties in liquid detergent formulations containing binary mixtures of anionic–nonionic, and anionic–cationic surfactants is discussed. Surfactants used include: linear alkylbenzene sulfonate (LAS), alcohol ether sulfate (AES-2EO), alcohol ethoxylate (AE-7EO), lauryl dimethyl amine oxide, and alkyl hydroxyethyl dimethyl ammonium chloride (AHDAC). Surface active parameters relating to the effectiveness and efficiency of surface tension reduction were determined from the surface tension data. Non-ideal solution theory was used to determine the degree of interactions between the two surfactants, and the conditions under which a mixture of two surfactants show synergism in surface active properties. Our data indicated that synergism in mixed surfactants increases with the degree of charge difference between the surfactants. In both mixed micelle and mixed monolayer formation, the degree of interactions between the two surfactants in the mixture increased in the following order: LAS/AE < AES-2EO/amine oxide < AES-2EO/AHDAC. This synergistic behavior as presented in this paper leads to unique application properties and improved performance in terms of foam volume, and soil removal which has applications in formulation of dishwashing liquids, and laundry detergents.     

New modified polyesteramide resin for industrial applications

Polyesteramide resins (PEA) combine the properties of both polyester and polyamide resins. These resins may be modified with various polyhydric alcohols to produce resins with modified properties. Hydroxy ethyl fatty acid amide (HEFA) is the main source of polyhydric alcohol used in polyesteramide resins. New modified polyesteramide resins were prepared and evaluated as anticorrosive varnish for industrial applications by partial replacement of hydroxy ethyl fatty acid amide (HEFA) with polyethylene glycol (PEG₄₀₀) without affecting the resin constants. Primer formulations based on these modified resins improve the films properties and show good physicochemical and corrosion inhibiting properties.     

Biodegradability and aquatic toxicity of glycoside surfactants and a nonionic alcohol ethoxylate

The environmental properties of three glycoside surfactants and one alcohol ethoxylate were examined by standardized laboratory methods. All of the surfactants biodegraded extensively in aerobic screening tests and may be assumed to approach 100% removal in aerobic wastewater treatment plants, except in cases of high loadings or otherwise exceptional conditions. Anaerobic biodegradability tests showed that an ethyl glycoside monoester (EGE) and a linear alkyl polyglycoside (APG) were both mineralized (>70%) under methanogenic conditions. In contrast, a branched APG resisted anaerobic degradation, while the alcohol ethoxylate was partially mineralized by anaerobic bacteria. The EGE surfactant was most rapidly mineralized in aerobic and anaerobic biodegradability tests. None of the surfactants inhibited respiration in activated sludge at the highest concentration tested (200 mg/L). Tests with aquatic organisms showed increasing toxicity in the following order: branched APG<EGE<linear APG<alcohol ethoxylate. Negligible aquatic toxicity was observed for the branched APG, while the alcohol ethoxylate was highly toxic to examined organisms. This evaluation demonstrates that considerable variation in biodegradability and toxicity responses can be seen within structurally related glucose-based surfactants.     

New tertiary amine-based surface active polymers

Surface active polymers with molecular weight ranging from 5600 up to 30,000 were synthesized by the oxyethylation of polyoxpropylene glycol adducts of ethylene diamine, which range in molecular weight from 4750 up to 6750. The toxicological properties of some of these new nonionics indicated that they would be nontoxic when used in contact with the skin and scalp. Their typical physical properties such as wetting, emulsifying, foaming and thickening are reported. A variety of cosmetic formulations has been prepared utilizing these new nonionic surface active polymers. This illustrates their versatility when used in products as diverse as a floating bath oil, an antiperspirant gel, a cold cream and a sun screen lotion. Presented at the AOCS Meeting, Chicago, October 1967.     

Influence of hydrophobe type and extent of branching on environmental response factors of nonionic surfactants

A number of ethoxylated nonionic surfactants differing in hydrophobe branching and chainlengths have been evaluated for environmental responses. Screening biodegradation tests show that those nonionics having more than one methyl group per hydrophobe degrade considerably slower than those having less extensive branching. Continuous flow-through activated sludge tests, simulating actual waste treatment, show that the more highly branched nonionics biodegrade more slowly and less extensively than those with less hydrophobe branching. In addition, treated effluents originating from influents containing the more highly branched nonionics tend to be more surface active and more toxic to aquatic species than those originating from influents containing surfactants with less hydrophobe branching. Under conditions simulating plant stress, such as high surfactant concentrations in the influent or low temperature, biodegradation of the highly branched nonionics was considerably less extensive, while biodegradation of the linear nonionics was not affected to any measurable degree compared to more normal operating conditions. Presented at the 81st American Oil Chemists’ Society Annual Meeting, April 22–26, 1990, Baltimore, Maryland.     

Synthesis and Characterization of Sodium Nonylphenol Ethoxylate(10) Sulfoitaconate Esters

Two sodium nonylphenol ethoxylate(10) sulfoitaconate ester surfactants, namely disodium nonylphenol ethoxylate(10) sulfoitaconate monoester (DNE(10)SIM) and sodium nonylphenol ethoxylate(10) sulfoitaconate diester (SNE(10)SID), were synthesized through the esterification and sulfonation reactions with nonylphenol ethoxylate(10) ester, itaconic acid and sodium sulfite as the raw materials. The chemical structures of the prepared surfactants were confirmed by FTIR and ¹H NMR. The surface tension of the synthesized surfactants was measured at 25 °C and the surface active properties were characterized. The DNE(10)SIM had better surface activity. The CMC was 1.77 × 10⁻⁶ mol L⁻¹ and γ_CMC was 35.45 mN m⁻¹. The CMC and γ_CMC for the SNE(10)SID were 5.42 × 10⁻⁵ mol L⁻¹ and 37.67 mN m⁻¹, respectively. Moreover, the emulsification power of SNE(10)SID was better.     

Novel Amide-Based Cationic Surfactants as Efficient Corrosion Inhibitors for Carbon Steel in HCl and H2SO4 media

A variety of surface active compounds were synthesized by the quaternization of some straight chain amide derivatives with triethylamine or pyridine. Their structure FT-IR and ¹H-NMR spectra were recorded. In addition their physical properties and corrosion prevention efficiencies were investigated. All compounds were tested with steel coupons in acidic media by the gravimetric method. As acidic media 1.5 M HCl and 1.5 M H₂SO₄ were used and the corrosion inhibition tests fulfilled at room temperature for 24 h. Almost all prepared cationic surfactants showed efficient inhibition around their critical micelle concentrations. The effects of HCl concentration on corrosion inhibition of some synthesized compounds were also investigated. The corrosion tests were supported by contact angle measurements.