Surface and thermodynamic parameters of mixed N-dodecyl N-trimethylsilane ammonium chloride with isooctyl phenol ethoxylate

Isooctyl phenol ethoxylate was mixed with N-dodecyl-N-trimethylsilane ammonium chloride and N-hexadecyl-N-trimethylsilane ammonium chloride, respectively. The surface tensions of aqueous solutions of cationic-nonionic mixtures were measured as a function of nonionic concentration at 35°C with constant cationic concentration. By using the Hutchinson method, the surface excess concentrations, surface mole fractions, and interaction parameters of binary surfactant mixtures were calculated. A synergistic effect for reducing surface tension was observed for adsorption at the surface at low concentrations of N-dodecyl-N-trimethylsilane ammonium chloride.     

Corrosion inhibition by N‐(alkyloxycarbonylmethyl)‐N‐triethanol ammonium chloride with respect to the surface and thermodynamic properties

N‐[(octyloxycarbonylmethyl)‐ N‐triethanol ammonium chloride] (C₈ ), N ‐[(dodecyl‐oxycarbonylmethyl)‐ N‐triethanol ammonium chloride] (C₁₂ ) and N ‐[(hexadecyloxycarbonylmethyl)‐N ‐triethanol ammonium chloride] (C₁₆ ) were synthesized. Surface tension was measured in aqueous solution for different concentrations at 28, 38 and 48°C. Various surface properties of the synthesized surfactants were evaluated, particularly critical micelle concentration (CMC), efficiency (Π_CMC) as well as maximum surface excess (Γ_max) and minimum surface area (A_min). Micellization and adsorption in both liquid/air and liquid/solid interfaces thermodynamics were investigated. These products have pronounced surface activity and satisfactory corrosion inhibition of C‐steel in hydrochloric acid at 28, 38 and 48°C. © 1999 Society of Chemical Industry     

Synthesis and Characterization of a Novel Series of Cationic Fumaric Polymerizable Emulsifiers

A series of novel cationic fumaric polymerizable emulsifiers (named as F series emulsifiers) were synthesized. The chemical structures of these emulsifiers were confirmed by ¹H NMR and MS and their minimal inhibitory concentrations to Escherichia coli were determined. Antibacterial tests of latex films showed that [2-(N-benzyl-N,N-dimethylamino)ethyl]dodecyl fumaric ammonium bromide, [2-(N-benzyl-N,N-dimethylamino)ethyl]decyl fumaric ammonium chloride and [2-(N-benzyl-N,N-dimethylamino)ethyl]dodecyl fumaric ammonium chloride can possibly be used as a polymerizable bactericides.     

Synthesis and Properties of Three N-Alkyl Bis-Quaternary Ammonium Salt Surfactants

Three N-alkyl bis-quaternary ammonium salt surfactants were synthesized by using epichlorohydrin, trimethylamine hydrochloride, and N,N-dimethylalkyl amine as raw materials in a two-step manner. The products were characterized by ¹H NMR and MS, confirming the successful synthesis of 2-Hydroxy-N¹,N¹,N³,N³-tetramethyl-N³-dodecylpropane-1,3-diammonium chloride (HPDDC), 2-Hydroxy-N¹,N¹,N³,N³-tetramethyl-N³-tetradecylpropane-1,3-diammonium chloride (HPTDC), and 2-Hydroxy-N¹, N¹, N³, N³-tetramethyl-N³-hexadecylpropane-1,3-diammonium chloride (HPHDC). Moreover, the influence of carbon chain length on surface-active properties, foaming properties, and paraffin liquid emulsion stability was investigated. Results indicated that critical micelle concentrations (cmc) decreased with increasing carbon chain length from 12 to 16, and the cmc and γ_cmc were lower than those of Dodecyl trimethyl ammonium chloride (DTAC). The products exhibited better foam properties and worse emulsifying performance than those of DTAC. The Krafft points of all products were determined to be below 0 °C. Moreover, the products also demonstrated outstanding antibacterial properties.     

Synthesis and Properties of Organosilicon Quaternary Salts Surfactants

Diethyl-benzyl-[3-methyldimethoxyl)]silpropyl ammonium chloride (DEBSAC) was synthesized from N,N-diethyl-aminopropyl-methyldimethoxysilane (DEAPMDES) and benzyl chloride. Diethyl-2,3-epoxypropyl-[3-methyldimethoxyl)] silpropyl ammonium chloride (DEEPSAC) was synthesized from DEAPMDES and epoxy chloropropane. Trimethyl-[3-methyldimethoxyl)] silpropyl ammonium chloride (TMSAC) was synthesized from trimethylamine and γ-chloropropylmethyldimethoxysilane (CPMDMS). The products were characterized by ¹H NMR, ¹³C NMR, and IR. The surface tension measurements showed that the organosilicon quaternary salts exhibit a lower surface tension and a lower critical micelle concentration (CMC) than the hydrocarbon counterparts. The plate count method experiments illustrated that DEEPSAC has a better degree of antibacterial activity against Escherichia coli than DEBSAC. The solubilizing effects of the organosilicon quaternary salts on organosilicone were studied by pseudo-ternary phase diagrams of synthesized products/cosurfactant(n-butanol)/water/octamethylcyclotetrasiloxane. The solubilizing activities decreased in the order of TMSAC > DEBSAC > DEEPSAC.     

Antibacterial materials: structure–bioactivity relationship of epoxy–amine resins containing quaternary ammonium compounds covalently attached

Bifunctional aminoalkyldimethylpropylammonium salts (N‐(3‐aminopropyl)‐N,N‐dimethylpentylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyloctylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyldecylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyldodecylammonium chloride) are synthesized and their structure‐dependent antibacterial effect against Gram‐negative Escherichia coli and Gram‐positive Lactococcus lactis is investigated. To this end, resins prepared from bisphenol A diglycidyl ether (2,2‐bis[4‐(glycidyloxy)phenyl]propane) and diethylenetriamine (2,2′‐diaminodiethylamine) as matrix and the bifunctional aminoalkyldimethylpropylammonium salts in a ratio of 6 mol% compared to epoxy components are used. A dependence of antibacterial effect on alkyl chain length of the quaternary ammonium compounds is observed for both species. Furthermore, resins with N‐(3‐aminopropyl)‐N,N‐dimethyldecylammonium chloride in varying concentrations up to 16 mol% for both organisms show a concentration‐dependent antibacterial effect of the quaternary ammonium salt. The antibacterial materials are characterized by differential scanning calorimetry, infrared spectroscopy and rheological studies. © 2013 Society of Chemical Industry     

3-Chloro-2-hydroxypropyl Dimethyl Dehydroabietyl Ammonium Chloride: Synthesis,Characterization, and Physicochemical Properties

3‐Chloro‐2‐hydroxypropyl dimethyl dehydroabietyl ammonium chloride (CHPDMDHA) was synthesized from dehydroabietylamine (DHA) and epichlorodrin. The synthesis was done in three steps. First, DHA was transformed into N,N‐dimethyl dehydroabietyl amine (DMDHA) through Eschweiler‐Clarke Reaction. Second, the DMDHA was reacted with hydrochloric acid and translated into DMDHA hydrochloride. Third, the CHPDMDHA was obtained after the DMDHA hydrochloride had reacted with epichlorodrin and recrystallized using a solvent composed of ethyl acetate and ethanol. The critical micelle concentrations (CMC) of CHPDMDHA at 25 °C was found to be 2.56 × 10^?4 mol L^?1, and its surface tension at the CMC (γ_CMC) was determined to be 27.4 mN m^?1; these data suggest that the surface activities of CHPDMDHA are better than those of benzalkonium chloride (BC), so that CHPDMDHA could be used as a good alternative to BC.     

Vinylester resin‐clay hybrids using various intercalating agents

Vinylester resin‐clay hybrids were prepared by the mixing different types of organically‐modified montmorillonite (OMMT) with vinylester resin (VER) prepolymer, followed by thermal polymerization. VER prepolymer was synthesized from the reaction of diglycidylether of bisphenol‐A (DGEBA) with acrylic acid. Various types of organic ammonium salts have been used as intercalating agents for montmorillonite, including N,N‐dimethyl‐N‐(4‐vinylbenzyl)stearyl ammonium chloride (VSA), N‐allyl‐N,N‐dimethyl‐stearyl ammonium chloride (ASA) and N,N‐dimethyl‐stearyl ammonium chloride (SA). The dispersion of OMMT into VER matrix was studied by XRD, which indicates the dependence of the morphology mainly on the OMMT content. UV–vis spectra of the hybrids were used to give a quantitative value of the effect of OMMT content on the transparency of VER/OMMT hybrid films. Also, the Vickers test has been performed to study the effect of OMMT content on the surface hardness of the hybrid films. In addition, the thermal properties of the hybrids have been characterized by measuring the softening points and thermogravimetric analyses of the hybrids in comparison with the pure resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and Characterization of Cationic Surfactants Based on N‐Hexamethylenetetramine as Active Microfouling Agents

Four cationic surfactants of quaternary hexammonium silane chloride based on hexamethylenetetramine and alkyl chloride were synthesized. The chemical structures of the prepared cationic surfactants were elucidated using Fourier transform infrared (FT‐IR) spectroscopy and mass spectrometry analysis. The surface and thermodynamic properties of the prepared surfactants were also studied. The performance of these cationic surfactants as microfouling agents against two strains of Gram‐negative bacteria, namely, Pseudomonas aeruginosa and Escherichia coli, and two strains of Gram‐positive bacteria, namely, Staphylococcus aureus and Bacillus subtilis, were evaluated as antimicrobial agents. The results showed that the maximum antimicrobial activity was detected for N‐hexamethylenetetramine‐N‐ethyl silane ammonium trichloride (Ah). The maximum and minimum antimicrobial activities were 73 and 60 % against S. aureus and E. coli, respectively, at a concentration of 5 mg/l, pH 7, and 37 °C.     

A Systematic Study of Mixed Surfactant Solutions of a Cationic Ester-Bonded Dimeric Surfactant with Cationic, Anionic and Nonionic Monomeric Surfactants in Aqueous Media

A novel cationic biodegradable dimeric (gemini) surfactant, ethane-1,2-diyl bis(N,N-dimethyl-N-hexadecylammoniumacetoxy) dichloride (16-E2-16), containing an ester-linked spacer was synthesized. Its pure and mixed micellization properties with monomeric surfactants cetyl trimethyl ammonium chloride, cetyl pyridinium chloride, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, cetyl alcohol ethoxylate (20EO) and tert-octylphenol ethoxylate (9.5EO) were investigated by surface tension measurements at 30 °C. The critical micelle concentration (CMC) of 16-E2-16 is well below that of cetyl trimethyl ammonium chloride containing the same number of carbon atoms in the hydrophobic tail per polar head. At different mole fractions of the gemini surfactant, the CMCs of the gemini-conventional binary mixtures were determined and were found to be less than the ideal CMC values in all the cases indicating synergistic interactions. Aggregation number and Stern–Volmer constant, obtained by the fluorescence quenching technique, also support the synergistic behavior of the surfactant systems.     

Cationic starch iodophores

Cross‐linked cationic starches N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch chloride (CQS chloride), N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch iodide (CQS iodide), and N‐(2‐hydroxyl)propyl‐3‐trimethyl ammonium starch iodide–iodine (CQS triiodide) with the degree of substitution (DS) according to cationic groups from 0.04 to 0.62, as well as cross‐linked starch–iodine complexes were synthesized and tested as potential antibacterial agents. Cationic starch iodine derivatives were obtained during ion exchange reaction between CQS chloride and iodide or iodide–iodine anions in aqueous solutions. CQS_DS≤0.3 chloride can form several types of iodine complexes, such as the blue amylose–iodine inclusion complex and ionic CQS⁺I^?·(I₂)_m complex (m ≥ 1). The antibacterial activity of modified starches–iodine samples against different pathogenic bacterial cultures and contaminated water microorganisms was evaluated. CQS chloride and CQS iodide were found to be bacteriostatic. A strong antibacterial activity was characteristic of CQS triiodides in which molecular iodine is present in both ionic and inclusion complexes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis and Interfacial Activity of Novel Heterogemini Sulfobetaines in Aqueous Solution

Three new heterogemini sulfobetaines and their chloride salts were synthesised. The interfacial activities of the obtained chlorides in aqueous solution were studied by equilibrium and dynamic surface tension measurements. The critical micelle concentration, surface excess concentration, minimum area per surfactant molecule and standard Gibbs energy of adsorption as well as micelle lifetime and diffusion coefficient were determined. The adsorption properties and micelle lifetime of these compounds significantly depend on the length of alkyl chain. The critical micelle concentration decreases with increasing chain length of the compounds considered. The values of the diffusion coefficient of N‐alkyl‐N‐methyl‐N‐(3‐sulfopropyl)‐6‐(N‐alkyl‐N‐methylamino)hexylammonium chloride tend to decrease as the concentration is increased.     

Imidazolium,Pyridinium and Dimethyl-Ethylbenzyl Ammonium Derived Compounds as Mixed Corrosion Inhibitors in Acidic Medium

Seven cationic surfactants: 1-methyl-3-tetradecyl imidazolium bromide, 1-methyl-3-hexadecyl imidazolium bromide, N,N-tetradecyl pyridinium bromide, N,N-hexadecyl pyridinium bromide, N,N-dimethyl-N-ethylbenzyl ammonium bromide, N,N-dimethyl-N-ethylbenzyl ammonium laurate and N,N-dimethyl-N-ethylbenzyl ammonium acetate, were investigated at different doses (10, 25, 50, 100, and 200 ppm) as corrosion inhibitors for steel grade API 5L X52 in hydrochloric acid 2 M using a weight loss technique, impedance and polarization resistance methods. The corrosion inhibition of steel grade API 5L X52 of the cationic surfactants was attributed to their molecular structure (heterocyclic ring, hydrophobic chain length and counterion) that enhances adsorption onto steel surface. The best protective efficiency of the film was higher than 90% (N,N-Dimethyl-N-ethylbenzyl ammonium acetate). It is important to know how organic inhibitor films grown on the metallic surface in order to achieve superior corrosion inhibition, hence experimental findings were described by Langmuir adsorption isotherm. The Electrochemical Impedance Spectroscopy spectrums were fitted by means of the Voigt model.     

The accelerating effect of a small cationic quaternary ammonium compound and the adsorption kinetics in the dyeing of silk with reactive dyes

In order to develop an eco‐friendly method for silk reactive dyeing that uses a lower accelerant dosage to achieve a higher dye fixation, hexyl dimethyl octyl ammonium chloride was synthesised as an accelerant for the dyeing of silk with reactive dyes. The accelerating effect, corresponding adsorption kinetics, and interaction mechanisms among hexyl dimethyl octyl ammonium chloride, reactive dyes, and silk were investigated. At hexyl dimethyl octyl ammonium chloride concentrations of 10.8–14.4 mm , the dye fixations for three reactive dyes were much higher than those achieved with sodium sulfate, even though the required dosages of hexyl dimethyl octyl ammonium chloride were 30–40 times lower than those of sodium sulfate. The wash fastness, rub fastness, light fastness, K/S, and colour difference values after dyeing with hexyl dimethyl octyl ammonium chloride were similar to those obtained using sodium sulfate, and silk can be dyed uniformly. The adsorption kinetics followed a second‐order kinetic model. The activation energies of surface adsorption for the three reactive dyes were lower than those of sodium sulfate. The high fixation of reactive dyestuffs and the low required dosage of hexyl dimethyl octyl ammonium chloride demonstrate that the use of this new accelerant provides a novel, highly efficient method for silk dyeing. A possible acceleration mechanism of hexyl dimethyl octyl ammonium chloride for reactive dyes adsorbed on the surface of silk was proposed, based on a series of activation parameters of the adsorption process.     

Investigations on the growth ofRhodococcus rubra in relation to the formation of stable biological foams

The growth characteristics of a foam-forming species,Rhodococcus rubra were studied on different substrates. The basic medium contained Czapek (3.34%), yeast extract (0.2%), potassium dihydrogen phosphate (0.12%), dipotassium hydrogen phosphate (0.25%) and ammonium chloride (0.1%). This was supplemented with varying concentrations of glucose (0–2%). The same basic medium was also used to examine the growth ofR. rubra in combination with varying concentration of n-hexadecane (0.0–0.5%) as a source of energy while varying the concentration of ammonium chloride in the range 1–3 gl ⁻¹. Studies based on determining the biomass concentration, the surface activity related to the cell suspensions and measuring the variations in broth pH revealed that glucose encouraged the growth ofR. rubra, compared to the control. However, increasing the glucose concentration from 0.1 to 2.0% had no further effect on growth. The surface activity of the cell suspensions increased with increasing glucose concentration. Results similar to glucose were exhibited by the addition of n-hexadecane, suggesting same degree of growth among different concentrations with higher surface activity increasing with increase in substrate concentration. Results have also shown that the pH of all the culture broths decreased as the ammonium chloride concentration increased, suggesting that there was a production of hydrogen ions during the course of its metabolism.     

Preparation of dialkoxyphosphinothioylthioacetamide insecticides

Dialkoxyphosphinothioylthioacetamides may be prepared conveniently in good yields and high purity from the reaction between dialkoxyphosphinothioylthioacetic acetic anhydrides and the appropriate amine. The necessary mixed anhydrides were readily prepared under very mild conditions by allowing keten to react with a dialkoxyphosphinothioylthioacetic acid in acetone. The method was applied to the preparation of both dimethoxy- and diethoxyphosphinothioylthioacetic anhydrides. The former was then interacted with methylamine to yield N-methyl dimethoxyphosphinothioylthioacetamide (dimethoate) or with morpholine to yield N-(dimethoxyphosphinothioylthioacetyl) morpholine. The diethoxy compound was converted to diethoxyphosphinothioylthioacetamide with ammonia. An alternative approach via the acid halides was examined. For this purpose dimethoxyphosphinothioylthioacetyl chloride and diethoxyphosphinothioylthioacetyl chloride and fluoride were prepared. They could not be obtained pure. The alkaline hydrolysis rates of dimethoxy- and diethoxyphosphinothioylthioacetic acids were determined and the acid dissociation constant of the latter compound was obtained by two methods.     

Phase transition in swollen gels 29. Temperature dependences of swelling and mechanical behaviour of poly(N-vinylcaprolactam-co-1-vinyl-2-pyrrolidone) gels in water

Summary Ionized networks of statistical copolymers of N-vinylcaprolactam (VCL), 1-vinyl-2-pyrrolidone (VP) (mole ratios of VCL/VP = 1/0, 0.9/0.1, 0.8/0.2, 0.7/0.3 and 0.5/0.5), an ionic comonomer, N,N-diallyl-(N,N-dimethyl)ammonium chloride (mole fractions 0, 0.005, 0.01 and 0.02) and a crosslinker, 1,1'-divinyl-3,3'-(ethane-1,1-diyl)di(2-pyrrolidone) (mole fractions 0.016, 0.024, 0.032 and 0.048) were prepared by radiation polymerization in water/ethanol mixture (H₂O/EtOH = 0.5/0.5 by vol). Their swelling and mechanical behaviour was investigated in water at various temperatures. For all copolymers, a continuous transition was found from the expanded (at low temperatures) to collapsed (at high temperatures) state; the transition temperature T _tr increases with increasing contents of VP and the ammonium salt in gels. The shift of T _tr to higher temperatures is caused by hydrophilicity of network chains increasing with increasing VP contents. The decrease in swelling with increasing temperature is accompanied by an increase in equilibrium modulus, so that mechanical behaviour is predominantly determined by swelling. Received: 31 October 2000/Revised version: 18 December 2000/Accepted: 18 December 2000     

Sorption properties of polymers based on N‐substituted maleimides

Physicochemical and functional properties of 2,2‐diallyl‐1,1,3,3‐tetraethylguanidinium chloride copolymers with N‐(n‐carboxyphenyl)maleimide, of N‐vinylpyrrolidone with N‐(n‐carboxyphenyl)maleimide, and of N‐vinylpyrrolidone with N‐phenylmaleimide have been investigated. Specific surface area and porosity of the copolymers under investigation have been determined by using the low‐temperature adsorption method. Electron microscope investigations in surfaces of the polymers have evinced that all of them have a spongy microstructure, the N‐vinylpyrrolidone copolymer with N‐(n‐carboxyphenyl)maleimide being the most homogeneous of these. Sorption capacity of the copolymers toward Re(VII) ions has been investigated. The process is described by the Langmuir isotherm. The pH is the most important parameter for sorption process of Re(VII). In the conjoint presence of Re(VII) and Mo(VI) in a solution of acid and ammoniac mediums, rhenium can be separated from molybdenum by using the sorbents under investigation at pH > 4.5 or at hydrochloric acid concentrations 0.1 mol L^?1 and more. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Salt Effect on the Solution Properties of Cationic Gemini/Conventional Surfactants in the Presence of the Nonionic Polymer Hydroxypropylmethyl Cellulose

In this article, we report the salt effect on interaction of a water-soluble polymer hydroxypropylmethyl cellulose (HPMC) with the cationic Gemini surfactant (ethane-1, 2-diyl bis(N,N-dimethyl-N-hexadecylammoniumacetoxy) dichloride, 16-E2-16), and also its monomeric counterpart cetyltrimethylammonium chloride (CTAC) using the tensiometric method. Surface tension of the amphiphiles diminished in the presence of the polymer as well as salts; eventually, the polymer gets saturated with the surfactant and there is no further change of surface tension of the solution. Interaction between the polymer and surfactant starts at the critical aggregation concentration (CAC) that is stronger for 16-E2-16 than CTAC. CAC and critical micelle concentration (CMC) values of the surfactant-polymer binary mixtures at various concentrations of the polymer were determined. CAC as well as CMC of 16-E2-16 are considerably lower than CTAC. The inorganic salts (KCl and KBr) have a considerable influence on the polymer–surfactant interaction.     

Micellar and Surface Properties of Some Monomeric Surfactants and a Gemini Cationic Surfactant

The physicochemical and interfacial properties of the monomeric surfactants cetyltrimethyl ammonium bromide (CTAB), cetyltriphenyl phosphonium bromide (CTPB), tetradecyl triphenyl phosphonium bromide (TTPB), cetyldiethylethanol ammonium bromide (CDEEAB), cetyltrimethyl ammonium chloride (CTACl), tetradecyltrimethyl ammonium bromide (TTAB), and a gemini surfactant (C₁₆-3-C_16, 2Br⁻) at different pH (3.1, 7.0, and 7.75) have been investigated by conductivity and surface tension measurements at 300 K. The critical micellar concentration (CMC), degree of micellar ionization (α), surface excess concentration (Г_max), minimum surface area per molecule of surfactant (A _min), Gibbs free energy of micellization (∆G _m⁰), surface pressure at the CMC (π _CMC), and the Gibbs energy of adsorption (∆G _ads⁰) of the monomeric surfactants have also been determined. The CMC, α and Г_max, increase with increasing pH whereas A _min decreases.