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1.
A novel series of glycerol-based double- or triple-chain surfactants with two sulfonate, two sulfate or two carboxylate groups was conveniently prepared by reactions of 1-O-alkylglycerol diglycidyl ethers with long-chain fatty alcohols, and followed by reactions with propanesultone, chlorosulfonic acid or bromoacetic acid, respectively. The sulfate and carboxylate types of compounds have higher water solubilities than the corresponding sulfonate type of compound bearing the same lipophilic group. The triple-chain surfactants show excellent surface-active properties, such as micelle forming and ability to lower surface tension, compared not only with the corresponding single-chain anionic surfactants, but also with the corresponding double-chain surfactants. The effect of the difference in head groups of these compounds on surface-active properties is described. Foaming properties, wetting ability and lime-soap dispersing requirement are also discussed.  相似文献   

2.
A series ofbis-quaternary ammonium salts was easily prepared by the reaction of a long-chaintert-alkylamine with epichlorohydrin, and their surface-active properties were measured. The prepared amphipathic compounds had good water solubility and showed characteristic surface-active properties, particularly, extremely excellent foaming ability and foam stability for some specific compounds, such as the compound with a dodecyl and a tetradecyl group as the lipophilic chains. Their critical micelle concentration, which decreased with increased alkyl chainlength, is two orders of magnitude lower compared with the conventionalmono-quaternary ammonium salts. In comparison with surface-active properties ofbis-quaternary ammonium salts, prepared from various organic dichlorides, there are little differences based on the kind of connecting group in the surface-active properties except for foaming.  相似文献   

3.
Bis(sulfonate) types of amphipathic compounds with three long- chain alkyl groups were prepared by the reaction ofN- (long- chain acyl)diethanolamine diglycidyl ethers with long- chain fatty alcohols, followed by the reaction with propanesultone. The diglycidyl ethers were easily obtained from the correspondingN- acyldiethanolamines and epichlorohydrin in the presence of a phasetransfer catalyst. The same types of compounds with two longchain alkyl groups were also prepared from Nacetyldiethanolamine according to similar procedures. All these new double- or triple- chain surfactants were soluble in water and showed much better micelle forming and ability to lower surface tension than general types of single- chain surfactants with one sulfonate group. The critical micelle concentration (CMC) and γCMC values of the triple- chain compounds were still much smaller than those of the corresponding double- chain compounds with two common alkyl groups. The efficiency of adsorption at the water/air interface (pC20) of these surfactants was very high. Their foaming properties, wetting ability toward a felt chip, and lime- soap dispersing ability were measured. To whom correspondence should be addressed at Department of Applied Chemistry, Faculty of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka 565, Japan.  相似文献   

4.
New compounds bearing two dihydrogen phosphate groups and two long- chain alkyl groups (octyl or decyl) were prepared in good yields by the reaction of 1,ω-bis(alkyloxymethyl)- oligo (ethylene glycol)s with polyphosphoric acid. Amphipathic di- or tetrasodium phosphates were obtained by neutralization of the free acids with sodium hydroxide, and their surface- active properties in water were measured. Almost all these di- or tetrasodium phosphates showed good water solubility. Their abilities to form micelles and to lower surface tension were fairly good as compared with general monoalkyl phosphates consisting of one longer alkyl chain and one hydrophilic group. The foaming property of aqueous solutions of the tetrasodium salts was different from that of the disodium salts. The former showed very low foaming ability.  相似文献   

5.
Amphipathic compounds having two phosphate groups and two long‐chain alkyl groups were prepared by a two‐step process: (a) preparation of monoalkyl phosphate from pyrophosphoric acid and dodecanol, (b) preparation of bis‐phosphoric acid from monoalkyl phosphate, (CH3)4NOH and 1,6‐dibromo hexane by using acetonitrile as solvent. The experimental results showed that a 5 : 10 : 2.5 molar ratio of reactants (alkyl phosphate/(CH3)4NOH/1,6‐dibromo hexane) and 3 h duration was the optimum for the reaction. The structure of the synthesized product was verified by analytical methods, viz. FT‐IR and 1H‐NMR. The surface‐active and performance properties like foaming, wetting and anionic content of the disodium salt of bis‐phosphoric acid were also evaluated. The synthesized anionic gemini surfactants possessed maximum anionic content, i.e. 73.4%, and showed better water solubility, foaming and wetting ability than conventional monoalkyl phosphates.  相似文献   

6.
Synthesis and characterization of the new polymeric ion exchangers with thiol and sulfonyl hydroxide groups are presented. These new sorbents were also compared with polymeric microspheres possessing methylenethiol groups on the surface presented previously. The polymeric cation ion exchangers in the form of microspheres were obtained by the suspension-emulsion polymerization tetrafunctional monomer: 2,3-(2-hydroxy-3-methacryloyloxypropoxy)naphthalene (2,3-NAF.DM) with styrene (St). Next, multistage modification introducing sulfur-containing group (thiol or sulfonyl hydroxide or methylenethiol) on the surface of polymeric matrices was made. In order to obtain sulfonyl hydroxide derivatives the matrices were performed as follows: the parent microspheres were treated by H2SO4 (Method I) or with the addition of oleum (Method II). The thiol groups were introduced in a two-stage reaction. In the first stage chlorosulfonation of parent microspheres in the presence of chlorosulfonic acid was carried out. Finally, the reduction of modified microspheres by using SnCl2·2H2O was conducted. The sulfur group content (elemental analysis, scanning electron microscope EDX SEM), thermal properties (thermogravimetric analysis), porous structure as well as the swelling characteristics of the functional beads were examined. The surface texture was also visualized by the AFM method.  相似文献   

7.
Novel cationic gemini surfactants, 1,3-bis[(acyloxyalkyl)dimethylammonio]-2-hydroxypropane dichloride, which possess hydrolyzable oxycarbonyl moieties in the lipophilic portions, were prepared. These surfactants showed much better micelle-forming ability, ability to lower surface tension, foaming ability, and foam stability than corresponding single-chain surfactants. Their surface properties were largely influenced by changing the position of the oxycarbonyl group in the lipophilic moiety. The critical micelle concentration decreased with a decreasing number of methylene units in the linking moiety between the ammonio and the oxycarbonyl groups within the comparison of lipophilic chains of the same length. These cationic gemini surfactants also showed good biodegradability.  相似文献   

8.
Two series of p-sulfobenzyl ammonium inner salts, RN+(CH3)2CH2C6H4SO3 and RCONH(CH2)3N+−(CH3)2CH2C6H4SO3, where R is a straight chain alkyl group, were prepared by sulfonation of the corresponding quaternary ammonium chlorides. Although both series have excellent lime soap dispersion properties, the former series gave optimum detergency at considerably shorter alkyl chain length than the latter serires. The detergency, lime soap dispersion ability, and solubility of these compounds were compared with those of structurally analogous aliphatic sulfobetaines. Structural variations, such as length and nature of the bridge between the cationic and anionic groups, length of the lipophilic chain, and insertion of an amidopropyl group into the lipophilic portion of the molecule, significantly altered the detergency and solubility but not the lime soap dispersing ability of the amphoterics.  相似文献   

9.
Our groups previously reported that conjugation at 3′-end with ursodeoxycholic acid (UDCA) significantly enhanced in vitro exon skipping properties of ASO 51 oligonucleotide targeting the human DMD exon 51. In this study, we designed a series of lipophilic conjugates of ASO 51, to explore the influence of the lipophilic moiety on exon skipping efficiency. To this end, three bile acids and two fatty acids have been derivatized and/or modified and conjugated to ASO 51 by automatized solid phase synthesis. We measured the melting temperature (Tm) of lipophilic conjugates to evaluate their ability to form a stable duplex with the target RNA. The exon skipping efficiency has been evaluated in myogenic cell lines first in presence of a transfection agent, then in gymnotic conditions on a selection of conjugated ASO 51. In the case of 5′-UDC-ASO 51, we also evaluated the influence of PS content on exon skipping efficiency; we found that it performed better exon skipping with full PS linkages. The more efficient compounds in terms of exon skipping were found to be 5′-UDC- and 5′,3′-bis-UDC-ASO 51.  相似文献   

10.
Surface active amphoteric derivatives were prepared from alkylbenzenesulfonyl chlorides. Industrial detergent alkylates, as well as benzene and pure 1-phenylalkanes whose side chains ranged from C1 to C12, were used as starting materials in this study of chemical structure-physical property relationships. The alkylbenzenes were first converted into the corresponding alkylbenzenesulfonyl chlorides with chlorosulfonic acid, and the sulfonyl chlorides were further treated with N,N-dimethyl-1,3-diaminopropane or N,N-bis-(2-hydroxyethyl)-1,3-diaminopropane. The reaction products were quaternized with propanesultone to produce amphoteric surfactants in high yields. The N,N-dimethyl herivatives of pure phenylalkanes were white crystalline powders, whereas the N,N-bis-(2-hydroxyethyl) derivatives were light , lime soap dispersing requirement, surface tension, wetting ability, and calcium ion stability were determined. The commercial detergent alkylate derivatives showed good detergency by themselves as well as in formulations with soap or with soap and silicate builder. Good lime soap dispersing properties were observed with compounds possessing a side chain of at least 4 carbon atoms. Presented at the AOCS Fall Meeting, Philadelphia, September 1974.  相似文献   

11.
Monodisperse polystyrene (PS) beads 2.5 μm in size were synthesized by dispersion polymerization. The PS beads were chemically modified by three different sulfonating agents, namely, concentrated sulfuric acid, acetyl sulfate, and chlorosulfonic acid. When they were sulfonated using chlorosulfonic acid, the concentration of sulfonic acid (SO3 ) groups on the PS beads increased from 0.5 to 2.25 meq/g as the treatment time was increased from 10 to 360 min at 0 °C. As the reaction temperature was increased, the ion-exchange capacity (IEC) of the sulfonated PS beads increased. However, it can be seen that they lost their spherical shape. The PS surface was modified by the introduction of the SO3 groups to give an IEC of up to 2.28 meq/g, which provides 1.1 × 1010 SO3 groups per bead, without any deformation of their spherical shape.  相似文献   

12.
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin.  相似文献   

13.
Medicinal and aromatic plants are highly prized all over the world. According to local cuisine and pharmacopoeias, they used to be important as dietary supplements, providing bioactive compounds. Herein, we describe lipophilic (fatty acids, tocopherols and carotenoids) and hydrophilic (ascorbic acid, sugars and phenolic compounds) antioxidants, lipid peroxidation inhibition and free radical scavenging activity in aerial parts of two Lamiaceae species (Mentha pulegium and Thymus pulegioides). M. pulegium gave the highest antioxidant properties (EC50<0.56 mg/mL), which is in agreement with its highest content in tocopherols, mainly α‐tocopherol (69.54 mg/100 g), ascorbic acid (7.90 mg/100 g), reducing sugars (7.99 g/100 g) and phenolics. The presence of these lipophilic and hydrophilic antioxidants could explain its use as antiseptic, anti‐inflammatory and as food preservative and special sauce. M. pulegium revealed the highest content of fat, α‐linolenic (ω‐3) and linoleic (ω‐6) fatty acids, while T. pulegioides revealed the highest content of carbohydrates (89.35 g/100 g). This could explain its use to improve the nutrition value of rye flour broth or potato based soups.  相似文献   

14.
The inhibitory potency of the series of inhibitors of the soluble epoxide hydrolase (sEH) based on the selenourea moiety and containing adamantane and aromatic lipophilic groups ranges from 34.3 nM to 1.2 μM. The most active compound 5d possesses aliphatic spacers between the selenourea group and lipophilic fragments. Synthesized compounds were tested against the LPS-induced activation of primary murine macrophages. The most prominent anti-inflammatory activity, defined as a suppression of nitric oxide synthesis by LPS-stimulated macrophages, was demonstrated for compounds 4a and 5b. The cytotoxicity of the obtained substances was studied using human neuroblastoma and fibroblast cell cultures. Using these cell assays, the cytotoxic concentration for 4a was 4.7–18.4 times higher than the effective anti-inflammatory concentration. The genotoxicity and the ability to induce oxidative stress was studied using bacterial lux-biosensors. Substance 4a does not exhibit genotoxic properties, but it can cause oxidative stress at concentrations above 50 µM. Put together, the data showed the efficacy and safety of compound 4a.  相似文献   

15.
This paper reports the synthesis of a series of novel compounds where carboxylic acids have been linked to a phenol through amidomethyl units. For instance, one, two, or three fatty acids have been selectively appended to the phenol in yields above 75%. The fatty acid used was oleic acid, which was subsequently epoxidized. Other functional groups, such as amino acids, can be incorporated in these compounds. Examples of monomers that are suitable for polymerization were also prepared: one acrylamide, one styrene derivative, and two types of AB2 diamino acids, all of which contain oleic units that are sites for epoxidation and crosslinking. Fatty acid aryl ethers were prepared using hydroxy fatty acids. These molecules are intended to serve as augmented analogues of epoxidized vegetable oil. Their amide groups should lead to intermolecular aggregation through hydrogen bonding, and the option to covalently include other functional groups may permit tuning of the macroscopic materials properties of films, coatings, or solids constructed from them.  相似文献   

16.
The sunflower‐like silica core‐polypyrrole (PPy) shell nanocomposites were prepared by using silica sulfuric acid as templates. The silica sulfuric acid was obtained by treating directly the silica nanoparticles with chlorosulfonic acid. The sulfonic groups (? SO3H) on the surface of silica sulfuric acid not only offered the active sites for formation of polypyrrole particles but also acted as dopant agents in PPy. The nanostructures of sunflower‐like silica/PPy nanocomposites and hollow PPy capsules were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The molecular structure and content of PPy were determined by Fourier transform infrared (FTIR) and thermal gravimetric analysis (TGA), respectively. The highest conductivity of nanocomposites is 2.4 S/cm. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

17.
Polypropylene fabrics were modified with 2N‐morpholino ethyl methacrylate by electron beams and grafting. Then, the modified fabrics were quaternized with different alkylating agents, such as benzyl chloride, monochloroacetic acid, chlorosulfonic acid, and chloroethanol. The reaction completion was calculated from the increase in the fabric weight. The modified polypropylene fabrics were characterized by microanalysis and IR spectroscopy. The moisture regain was measured at 20°C and 65% relative humidity. The modified fabrics were sufficiently hydrophilic to adsorb the metal ion Cu2+ from a CuSO4 solution. Their antimicrobial properties were evaluated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2917–2922, 2003  相似文献   

18.
Inhibition of catalytic oxidation of carbon/carbon composites by phosphorus   总被引:1,自引:0,他引:1  
The inhibition effectiveness of thermally deposited phosphorus (P) compounds on the carbon oxidation catalyzed by potassium or calcium acetate has been investigated. The P deposit was formed by impregnating carbon/carbon composite samples with methanol solution of methyl-phosphoric acid or phosphorus oxychloride and heating at ca. 600 °C. An amorphous layer formed by a relatively large amount of P deposit functioned as a barrier for the access of the catalyst to the carbon surface even though it had almost no barrier effect for O2 access. The catalytic effect of calcium was almost completely suppressed by such deposit, but the effect of potassium was only partially suppressed due to the superior wetting ability and mobility of potassium species. Small amounts of P deposit showed similar inhibition effects on non-catalyzed oxidation, while their effects on catalytic oxidation were not as good. Characterization of P-deposited carbon samples by XPS, XRD, SEM and TPD, as well as ab initio MO calculations, suggested that the inhibition effect mainly resulted from the formation of oxygen-containing P groups which may include metaphosphates, C-O-PO3 groups and C-PO3 groups. Those groups are suggested to act as a physical barrier against carbon/catalyst interfacial contact as well as to block the active carbon sites. The presence of bridge oxygen bonded to a carbon site and a P group appears to be a critical factor for maintaining the inhibition effect. Indeed, the loss of such oxygen or connecting bond seems to result in loss of inhibition.  相似文献   

19.
A new method to introduce iminodiacetic acid (IDA) onto polyethersulfone (PES) matrix through chlorosulfonation was described in this work, and the prepared PES‐IDA was used as adsorbent for the removal of metal ions from aqueous solutions. Chlorosulfonic groups ( SO2Cl) were introduced onto PES first, then IDA was grafted onto PES by using the interactions between the chlorosulfonic group and the imino group of IDA. The grafted IDA was characterized by fourier transform infrared measurement, X‐ray photoelectron spectroscopy analysis, and thermogravimetric analysis spectra. The adsorbed amounts by the PES‐IDA for Cu2+ and Ag+ were 3.44 mg/g and 7.09 mg/g, respectively. The PES‐IDA adsorbent may expand the usage of PES in purification fields and could make some potential contributions to the polymer‐based adsorbents. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

20.
Alkylbenzenes, such as industrial detergent alkylates, as well as pure 1-phenylalkanes whose side chain lengths varied C8−C12, were converted into the corresponding alkylbenzenensulfonyl chlorides with chlorosulfonic acid. Surface active sulfonamides were obtained from the reaction of the sulfonyl chlorides with various low mol wt aminosulfonic acids, such as N-methyltaurine, or with aminoalkyl esters of sulfuric acid, such as 2-aminoethyl hydrogen sulfate. The hydrolytic stability of the resulting surface active sulfonamide derivatives was investigated. As expected, the sulfonates were quite resistant to acid or alkaline hydrolysis, while the sulfates were more susceptible to hydrolysis. Hydrolytic stability of the sulfonamides was compared with that of the analogous fatty acid amide sulfactants. All of the compounds were excellent lime soap dispersing agents giving Borhetty-Bergman values of 4–10. The compounds were evaluated for detergency either alone or formulated either with tallow soap or with tallow soap and sodium silicate (Na2O/SiO2 ratio of 1∶1.6) The derivatives of the pure hydrocarbons which gave the best overall detergency were those of 1-phenyldecane and 1-phenyldodecane, whereas those of 1-phenyloctane exhibited poor detergency. This ranking was observed when the compounds were tested alone as well as when formulated. The sulfonamide derivatives of the detergent alkylate type of alkylbenzenes exhibited excellent detergency characteristics and showed substantial potentiation of detergency when mixed with soap or with a soap-sodium silicate blend. The detergency performance of some of these formulated detergents was equal to that of a commercial household detergent used as a control.  相似文献   

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