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1.
Ester-adduct derivatives of rosin were synthesized by reacting rosin maleic anhydride (RMA) or rosin acrylic acid (RAA) adducts with polyethylene glycol 600 (PEG600), 1000 (PEG1000) or 2000 (PEG2000) and at elevated temperature. These derivatives were evaluated for acid number, FTIR spectroscopy, molecular weight (Mw) and polydispersity. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin) and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed.  相似文献   

2.
Water-soluble surfactants based on rosin acids were synthesized from condensed rosin acid-formaldehyde. This was completed by esterification of series of rosin acid formaldehyde resins with poly(ethylene glycol) having different molecular weights to produce series of rosin esters. The structure of the produced resins was determined by infrared and 1HNMR analysis. The molecular weight of the produced surfactants was determined by gel permeation chromatography (GPC) technique. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed. The dispersion efficiency of the prepared surfactants as petroleum oil spill dispersants was determined and correlated with the surface activity, concentrations of the prepared surfactants and type of petroleum crude oil.  相似文献   

3.
This work aims to measure the adsorption and micellization parameters of new water soluble nonionic amphiphilic block and graft copolymers based on hydrophilic poly (ethylene glycol) (PEG) and hydrophobic poly (propylene oxide) (PPO) at ambient temperature and normal atmospheric pressure. The chemical composition and molecular weights of the prepared copolymers were determined from 1H NMR analyses. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration, the area per molecule at interface and the effectiveness of surface tension reduction were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption and micellization process were calculated and are discussed.  相似文献   

4.
Recycling of PET waste was carried out in presence of diethanolamine and manganese acetate as catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol, PEG, which have different molecular weights 400, 1,000, and 4,000 to produce nonionic polymeric surfactants having different hydrophilic‐hydrophobic balance (HLB). The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. From the adsorption isotherm, some thermodynamic data for the adsorption process are calculated and discussed.  相似文献   

5.
Water soluble nonionic surfactants based on Schiff base monomers were prepared by their etherification with β,` β- dichlorodiethylether and PEG 400 in presence of NaOH. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The prepared nonionic surfactants were evaluated as demulsifiers for synthetic water in crude-oil emulsions that were pronounced at different ratios of crude oil: water at 45°C and 60°C. The experimental results showed that the dehydration rate of the prepared demulsifiers reached 90% and 100% at some concentrations.  相似文献   

6.
Novel polymerizable surface-active monomers were synthesized by successive treatment of polyoxyethylene 4-nonyl-2-prpylene-phenyl ether ammonium sulfate with maleic anhydride in the presence of hydroquinone at temperature of 180°C. The molecular structures of the polymerizable surfactants were confirmed by 1H and 13C NMR spectroscopy. The surface tension isotherms on the air-water solution interface were obtained. The critical micelle concentrations (cmc) as well as the surface tension at the cmc were determined for these substances. The micellization and adsorption of the prepared anionic surfactants have been investigated by surface tension, and cloud point measurements. Surface parameters such as surface excess concentration (Γ max), the area per molecule at interface (A min) and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants.   相似文献   

7.
Poly (ethylene terephthalate), PET, waste was recycled to oligomers in the presence of triethanolamine and manganese acetate as a catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol having different molecular weights 400, 1000, and 4000 to produce nonionic polymeric surfactants having different hydrophile‐hydrophobe balances (HLB). The surface tension, critical micelle concentration (CMC) and surface activities were determined at different temperatures. Surface parameters such as, surface excess concentration Γmax, the area per molecule at interface Amin and the effectiveness of surface tension reduction (ΠCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process are calculated and discussed.  相似文献   

8.
Water soluble nonionic amphiphilic block copolymers based on hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(propylene glycol) (PPG) were prepared. Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymers, PEG-PPG-PEG, were prepared in the normal condition. The chemical composition and molecular weights of the prepared copolymers were determined from 1H NMR and GPC techniques. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The prepared nonionic surfactants were evaluated as demulsifiers for water in crude-oil emulsions that were pronounced at different ratios of crude oil: water at 318 K and 333 K. The experimental results showed that the dehydration rate of the prepared demulsifiers reached 100% based on demulsifier chemical compositions and concentrations.  相似文献   

9.
Three series of nonionic N-alkylaldonamides, N-alkyl-N-methylgluconamides (Cn-MGA, Cn: n-C(10)H(21), n-C(12)H(25), n-C(14)H(29), n-C(16)H(33), and n-C(18)H(37)), N-alkyl-N-methyllactobionamides (Cn-MLA, alkyl as above-mentioned), and N-oleyl-N-methylglucon/lactobionamide, were synthesized in the reaction of an appropriate N-alkyl-N-methylamine with delta-D-glucolactone and lactobionic acid, respectively. Krafft temperatures of aqueous solutions and surface properties of these surfactants at 20 degrees C, i.e., surface excess concentration, Gamma(cmc), surface area demand per molecule, A(min), efficiency in surface tension reduction, pC(20), effectiveness in surface tension reduction, Pi(cmc), critical micelle concentration, CMC, and CMC/C(20) parameter as well as standard free energies of adsorption, DeltaG degrees (ads), and of micellization, DeltaG degrees (mic), were determined. It was shown that introduction of the methyl group to the amide nitrogen increased the solubility of the surfactants, which was confirmed by their Krafft temperatures. Lactobionamides are more water soluble than gluconamides. On the other hand, the Cn-MGA surfactants are more surface active than the respective Cn-MLA ones. This observation is based on the determined adsorption and micellization parameters. The presence of one double bond in a hydrocarbon chain as in oleyl-amides increases their hydrophilic character compared with that of saturated C18 derivatives. No distinct differences were observed between the A(min) values obtained for both series studied, although they differ markedly in the size of the hydrophilic groups. Copyright 2001 Academic Press.  相似文献   

10.
Hydrophobically modified polyacrylamide (PAAm) was prepared by grafting PAAm with block copolymer of poly(ethylene oxide) and poly(propylene oxide), PEO‐PPO‐PEO, by melt method in the presence of benzoyl peroxide as initiator. The chemical structure of the graft copolymer was determined by FTIR and 1HNMR analyses. The surface tension, critical micelle concentration, and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (ΠCMC) were determined at different temperatures from the adsorption isotherms of the prepared surfactants. The prepared surfactant was tested as emulsifier for water with xylene, cyclohexane, or petroleum crude oil synthetic emulsions. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

11.
The chemical structure of newly synthesized cationic surfactants based on Schiff base was confirmed using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and mass spectroscopy. The synthesized surfactants were used in the synthesis of silver nanoparticles by a simple one-step method. The silver nanoparticle (AgNPs) formation was confirmed using transmission electron microscopy (TEM), electron diffraction (SAED), dynamic light scattering (DLS), and energy dispersive X-ray spectroscopy (EDX). The structure of the surfactant played an important role in the synthesis process. Increasing the hydrophobic chain length, the stability, and the amount of surfactant increased the quantity of AgNPs formed. The surface activity of the synthesized cationic surfactants was determined using surface tension measurements at three different temperatures. The synthesized surfactants showed a high tendency toward adsorption and micellization. Increasing the hydrophobic chain length of the synthesized surfactant increased its adsorption. Screening the synthesized cationic surfactants and their nano-form against bacteria and fungi showed that they are highly effective. The silver nanoparticles enhanced the biological activity of the synthesized cationic surfactants.  相似文献   

12.
The amphiphilic character of cellulosic copolymers offers the opportunity to employ their derivatives as novel bio-friendly stable amphiphilic agents. It can be speculated that the synthesized nanobiostructures with hydrophilic and hydrophobic segments will have micellar features. Our investigations, for the first time, demonstrate that the amphiphilic nature of the synthesized macromolecules based on hydrophobic cellulose triacetate (CTA) and hydroxyl terminated oligomeric species of CTA (HCTA) by using hydrophilic polyethylene glycol (PEG) with Mn 600 and 2000 D as CTA-g-PEG, 600; CTA-g-PEG, 2000; HCTA-b-PEG, 600; and HCTA-b-PEG, 2000. The characteristic features of the copolymers were determined by XRD, differential scanning calorimeter, 1H NMR, FTIR, GPC, dynamic light scattering measurements, and transmission electron microscopy. In addition, their critical micelle concentrations were evaluated. The obtained results indicated that the hydrophobic blocks make a significant influence on the micellar characteristics of the surfactants. A comparison of the micellar behavior of a hydrophobic species, like pyrene, incorporated in the synthesized systems indicated that the incorporation content of the surfactants is influenced by the hydrophobic and hydrophilic chain lengths. Therefore, it is possible to design the diversity of the surfactants based on various hydrophilic/lipophilic balance.  相似文献   

13.
The synthesis of surfactants derivatives of new two series of cationic gemini surfactants containing ethane or benzene as a spacer are described. The prepared compounds were analyzed using standard tools of analysis, elemental analysis, FTIR measurements, and H1 NMR spectra. The influence of dimerization and of the spacer group were examined in order to establish structure-property relationships. The critical micelle concentration (CMC) of each series has been determined using equilibrium surface tension measurements. Furthermore, air/water interface parameter including effectiveness (Πcmc), efficiency (P20), maximum surface excess (τmax), and minimum surface area (Amin) have been also derived using Gibbs adsorption equation at 25°C. Standard free energies of micelleization were calculated and biological activities were examined. The results revealed that the dimeric surfactants have a good effect on the biological activities.  相似文献   

14.
去氢枞酸蔗糖酯的溶剂法合成   总被引:22,自引:4,他引:18  
松香主要成分是二萜树脂酸(C29H29COOH,含量约为90%),可用作表面活性剂的合成原料。将松香树脂酸与蔗糖进行酯化反应,即可合成松香-蔗糖基非离子表面活性剂。目前关于高级脂肪酸蔗糖酯和松香基表面活性剂的研究有许多报道,但有关松香蔗糖酯的研究报道极少,工艺极不成熟,且都使用未经改性的松香,结构中仍保留两个易氧化的双键,不利于长时间储存和使用。从歧化松香中分离提纯去氢枞酸,  相似文献   

15.
Six new surfactant blends were prepared by mixing one Schiff base non ionic surfactant prepared by etherification of Schiff base monomer with β` β-dichlorodiethylether and PEG 400 in presence of NaOH with six water-soluble Schiff base nonionic surfactants prepared in the same way but etherified with PEG 2000. The mixing process was based on the high dehydration rates given by the PEG 400 Schiff base surfactant compared to the other PEG 2000 surfactants. The experimental results of this study indicate that the demulsification rates of these blends are higher than those of the PEG 400 surfactant. Demulsification process was carried out on an emulsion of w/o ratio 50:50 and studied at 60°C at two different concentrations of the demulsifiers (200 and 240 ppm). The dehydration rates of the six prepared blends reached 100%. The total dehydration time varied from 50 minutes up to 2 hours.  相似文献   

16.
N-hydroxyethyl-3-alkyloxypyridinium amphiphiles have been synthesized and characterized by various spectroscopic techniques. Self-assembling properties of these amphiphiles have been studied by surface tension, conductivity, and fluorescence measurements. Basic micellization parameters like critical micelle concentration (cmc), surface tension at the cmc (γ cmc), adsorption efficiency (pC20), effectiveness of surface tension reduction (Π cmc), maximum surface excess concentration (Γ max) and minimum surface area/molecule (A min), and Gibbs free energy of the micellization (ΔG0 mic) have also been determined. The micellization of these 3-alkyloxypyridinium halides in aqueous phase have been found to be exothermic and entropy-driven as assessed by conductivity measurements at different temperatures. Thermal degradation of these surfactants has also been assessed by thermal gravimetric analysis under nitrogen atmosphere. Further, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay of these surfactants on C6 glioma cells show them to be less toxic than conventional cationic surfactants.  相似文献   

17.
Two series of cationic dimeric (gemini) surfactants are prepared with respect to key surfactants properties, such as surface activity and solubilization. The influence of both the dimerization and the spacer group is examined in order to establish structure-property relationships. The surface tension and critical micelle concentration can be markedly reduced compared to the monomeric surfactants in the pure state. The critical micelle concentration (cmc) of each series has been determined using equilibrium surface tension measurements. Furthermore, air/water interface parameters including effectiveness (πcmc), efficiency (PC20), maximum surface excess (Γ max ), and minimum surface area (A min ) have been also derived using Gibb's adsorption equation at 25°C. Standard free energies of micellization and adsorption were calculated. Solubilization behaviors of the synthesized surfactants were measured towards paraffin oil as solubilized material using light transmission technique.  相似文献   

18.
Novel surface-active monomers were synthesized by successive treatment of tert-butylperoxy-6-hydroxyhexanoate with maleic anhydride, 1,3-propane sultone and triethylamine or with maleic anhydride and poly(ethylene glycol) methyl ether. The surface-active properties of monomers were studied. The critical micelle concentrations (cmc) as well as the surface tension at the cmc were determined for obtained monomers. The synthesized compounds were shown to be suitable reactive surfactants for obtaining styrene latexes.  相似文献   

19.
研究了以丙烯酸改性松香为原料合成新型丙烯酸改性松香双季胺盐型阳离子表面活性剂的工艺,测定了它们的理化性质和表面性能,诸如含水量、含N量、阳离子活性物含量、Krafft点、表面张力、乳化力、泡沫力及泡沫稳定性等,表明它们具有良好的表面活性,并对其进行了红外光谱表征。  相似文献   

20.
N-Methylethylolamides have been synthesized on the basis of vegetable oils (corn, coconut, canola, olive, cotton-seed, and palm) and modified with orthophosphoric acid. The structure of the synthesized N-methylethylolamides and their phosphate derivatives has been identified by IR and NMR spectroscopies. Surface activity of the N-methylethylolamides and their derivatives at the water–air border has been determined and their colloidal-chemical parameters (maximum surface excess concentration and minimum area per molecule at the aqueous solution–air interface, surface pressure at the critical micellization concentration (CMC), standard thermodynamic parameters of adsorption and micellization) have been calculated. The character of influence of the surfactants structure on their colloidal-chemical parameter has been clarified. The petroleum-collecting and petroleum-dispersing capacities of the synthesized surfactants have been studied on the surface of the water of various mineralization degrees.  相似文献   

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