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1.
马来酸酐双酯型表面活性单体的合成和性质   总被引:18,自引:2,他引:18  
表面性单体(也称为可聚合表面活性剂),既具有表面活性又可以与聚合单体发生聚合反应,可以改善聚合物乳液的稳定性,提高乳液成膜后的耐水性,其中以马来酸酐为反应基团的表面活性单体,由于其不易发生均聚反应而具有特殊的意义,首先以马来酸酐和十二醇为原料制备马来酸酐单十二醇酯,然后与环氧丙基三甲基氯化胺反应合成了3种新型的马来酸酐双酯型阳离子表面活性单体,产品的结构用红外光谱,核磁共振氢谱以及元素分析进行了表征,该产品能显著降低水的表面张力(22mN.m^-1,26mN.m^-1),并具有较低的临界胶束浓度(0.2mmol.L^-1-0.6mmol.L^-1)。  相似文献   

2.
Poly(ethylene terephthalate) waste was recycled to oligomers in the presence of diethanolamine and manganese acetate as a catalyst. The oligomers produced were reacted with stearic acid and poly(ethylene glycol) with different number average molecular weights of 400, 1000 and 4000 g mol?1 to produce nonionic polymeric surfactants having different hydrophile–hydrophobe balances. 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. Copyright © 2007 Society of Chemical Industry  相似文献   

3.
3种燕尾形双子表面活性剂的合成及其表面活性   总被引:1,自引:1,他引:0  
赵永  刘峥  云亮  谢元健 《化工学报》2016,67(4):1424-1432
设计合成了3种基于五苯基苯骨架结构的苝二酰亚胺衍生物n-PDI(n 2,3,4)双子表面活性剂,利用红外光谱仪、核磁共振氢谱仪、热重分析仪,对所合成的3种目标产物结构进行表征与确认,它们的分解温度均在200℃以上。研究了3种双子表面活性剂表面活性参数和热力学参数,结果表明双子表面活性剂分子在水溶液中形成胶束和在气-液界面处的吸附过程是自发的;且双子表面活性剂分子形成胶束的过程易于进行;随温度的升高ΔGmic?、ΔHmic?、ΔSmic?均减小,表明ΔHmic?对ΔGmic?的贡献有增大趋势,ΔSmic?对ΔGmic?的贡献有下降趋势,即胶束化过程为熵驱动力在减小而焓驱动力在增大的过程。由SEM测试表明双子表面活性剂能有效吸附在锌电极表面,对其具有缓蚀作用。  相似文献   

4.
The thermodynamic properties of some low molecular weight ethoxylated alkylphenol formaldehyde polymeric surfactants have been investigated. Surface tension as a function of concentration of the surfactants in aqueous solutions was measured at 28, 38, 48 and 58°C, using the spinning drop technique. From these measurements, the minimum area per molecule at the aqueous solution/air interface (Amin) was determined. The thermodynamic parameters of micellization (ΔGmic, ΔHmic, ΔSmic) and of adsorption (ΔGad, ΔHad, ΔSad) for these polymeric nonionics were calculated. Micellization is more sensitive to ethylene oxide chain length while adsorption is more dependent on the length of the alkyl chain.  相似文献   

5.
The chemical structure of the prepared cationic surfactants which formed through condensation reaction between dimethylaminopropylamine (DMAPA) and butyraldehyde then quaternized by three fatty alkyl bromide was confirmed by FTIR, 1HNMR and mass spectroscopy. The chemical structure of prepared compounds has an effect on surface properties. By increasing the hydrophobic chain length, the values of CMC and Гmax decrease while Amin value was increased. The Thermodynamic parameters showed that adsorption and micellization processes are spontaneous. It is clear that the prepared cationic surfactants tend to adsorb at surface, then it aggregate to form micelle. The prepared surfactants showed good biological activity against Gram-positive and negative bacteria and fungi. The prepared cationic surfactant showed aggressive effect on the sulfate reducing bacteria growth.  相似文献   

6.
A series of noncyclic acetal-linked cleavable surfactants were simply prepared by condensation of aldehydes with poly(ethylene glycol) monomethyl ethers. All of the products were characterized by1H nuclear magnetic resonance. Their hydrophile-lipophile balance, surface tension, cloud point, critical micelle concentration, and foam height were determined. Hydrolysis kinetic studies, followed by gas chromatography, showed that they had higher hydrolytic reactivity in acidic solution than cyclic acetal-linked cleavable surfactants.  相似文献   

7.
ABSTRACT

The adsorption and micellization processes of 3-alkyloxy aniline namely [3-decyloxy aniline (C10M), 3-dodecyloxy aniline (C12M) and 3-cetyloxy aniline (C16M)] and their polymers [C10P, C12P and C16P] have been investigated using surface tension (γ) measurements at different temperatures. The synthesized monomers and polymers have been characterized by IR and elemental analysis. The surface and thermodynamic parameters of these monomeric and polymeric surfactants are investigated. The results show that the critical micelle concentration (CMC) of the polymeric surfactants is lower than that of monomers. The CMC values decreases as the hydrophobic chain lengthens for both monomeric and polymeric surfactants. The surface parameters show the ability of monomeric and polymeric surfactants to adsorb at the air/water interface and decrease the surface tension. The thermodynamic parameters reveal that the micellization process is spontaneous for all investigated surfactants. The specific conductance measurements show that the specific conductance increases with increasing chain length of the substituted alkyl groups, the synthesized polymeric surfactants have higher values of specific conductance than the corresponding monomers and the specific conductance increases with rising solution temperature.  相似文献   

8.
High-performance surfactants have been developed for the preparation of water-in-oil high internal phase emulsions (HIPE), particularly for the preparation of polymerized HIPE foams. High-efficiency surfactants with poly(butylene oxide)/poly(ethylene oxide) (BO/EO) block copolymer backbones have been developed that can stabilize an HIPE through polymerization at concentrations as low as 0.006 wt% based on total emulsion weight. Polymerizable versions have been developed that bind into the polymeric foam backbone. BO/EO block copolymer surfactants also allow preparation of polymerized HIPE foams without salt in the aqueous phase. HIPE with the BO/EO surfactants have been prepared at room temperature and polymerized at temperatures exceeding 90°C. By minimizing the required amount of surfactant, allowing the surfactant to react during HIPE polymerizations, eliminating the need for salt, and stabilizing over a broad range of temperatures, BO/EO block copolymer surfactants have demonstrated their place as high-performance HIPE surfactants.  相似文献   

9.
Fiber formation from atactic polystyrene (aPS) and alternating poly(styrene‐maleic anhydride) (PSMA) synthesized by free radical polymerization (AIBN, 90°C, 4 h) were investigated by electrospinning from various solutions. aPS was soluble in dimethylformamide (DMF), tetrahydrofuran (THF), toluene, styrene, and benzene, whereas PSMA was soluble in acetone, DMF, THF, dimethylsulfoxide (DMSO), ethyl acetate, and methanol. aPS fibers could be electrospun from 15 to 20% DMF and 20% THF solutions, but not from styrene nor toluene. PSMA, on the other hand, could be efficiently electrospun into fibers from DMF and DMSO at 20 and 25%, respectively. Few PSMA fibers were, however, produced from acetone, THF, or ethyl acetate solutions. Results showed that solvent properties and polymer–solvent miscibility strongly influenced the fiber formation from electrospinning. The addition of solvents, such as THF, generally improved the fiber uniformity and reduced fiber sizes for both polymers. The nonsolvents, however, had opposing effects on the two polymers, i.e., significantly reducing PSMA fiber diameters to 200 to 300 nm, creating larger and irregularly shaped aPS fibers. The ability to incorporate the styrene monomer and divinylbenzene crosslinker in aPS fibers as well as to hydrolyze PSMA fibers with diluted NaOH solutions demonstrated potential for post‐electrospinning reactions and modification of these ultrafine fibers for reactive support materials. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

10.
The polyanionic polymer poly(maleic acid-alt-2-cyclohexyl-1,3-dioxepin-5-ene), poly(MA-CDA), was developed as an immunomodulator. It was found that the cell affinity of poly(MA-CDA) could be significantly enhanced by hydrophobic chemical modification. This paper deals with the biological activities of poly(MA-CDA) and hydrophobically modified poly(MA-CDA), including immunostimulating activity, antitumour activity and antiviral activity. © 1998 SCI.  相似文献   

11.
The adsorption behavior of synthesized anionic surfactants with the chemical structure RO-Ph-N=N-Ph-SO3Na, where R is an octyl, dodecyl, or cetyl group, was analyzed by using a modified version of the Frumkin adsorption isotherm. The values of thermodynamic parameters (including free energy of micellization, ΔG mic, and of adsorption, ΔG ads) at the solution/air interface and the solid/liquid interface were calculated, and the relation between the adsorption of the surfactants at these interfaces was investigated. Studies of the surface properties of these synthetic surfactants showed that the length of the hydrocarbon chain of these surfactants plays a major role in determining their surface and thermodynamic properties and that there is a good relationship between the effectiveness of adsorption of the surfactant and its efficiency as a collector.  相似文献   

12.
For improved surface properties, nonwoven fabrics of polypropylene and poly(ethylene terephthalate) were treated with several kinds of surfactants, including anionic, cationic, and nonionic types. The adsorption isotherms of the anionic, cationic, and nonionic surfactants on the nonwoven fabrics were different. The adsorption isotherm of the cationic surfactant (dodecyl dimethylbenzyl/ammonium chloride) exhibited a maximum. The adsorption isotherm of the anionic surfactant (sodium dodecylbenzene sulfonate) was in the shape of the fifth Brunauer adsorption isotherm, and that of the nonionic surfactant (alkylphenol/ethylene oxide condensate) was similar to the fourth Brunauer adsorption isotherm. The time of the adsorption equilibrium was constant for the same types of adsorbate and adsorbent, and it was not related to the initial concentration. The specific surface resistance of the nonwoven fabrics decreased substantially after the adsorption of ionic surfactants. The nonwoven fabrics with the surfactants were characterized with scanning electron microscopy and X‐ray photoelectron spectroscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3210–3215, 2003  相似文献   

13.
综述了近二十年来聚合表面活性剂的合成及主要应用,详细阐述了国内外对低聚表面活性剂在合成、界面吸附和溶液聚集行为方面的研究进展.已有的研究结果表明,中低分子质量的线性聚合表面活性剂不但具有很高的界面活性,可以使原油/水的界面张力达到超低,而且兼具一定的黏度,在三次采油上将具有很大的应用前景.  相似文献   

14.
Several equation models were investigated to find the relationship between temperature (T). number of ethylene oxide (EO) units (n) or the hydrophile-lipophile balance (HLB) and the surface and thermodynamic properties of some ethoxylated alkylphenol-formaldehyde polymeric nonionic surfactants. These properties include critical micelle concentration (CMC), free energy of micellization (ΔGmic), surface tension at CMC (7CMC), effectiveness (γCMC) and efficiency (pC20) of surfactant to reduce the surface tension of water. The values of the ratio CMC/C2(π = 20) were also considered. The linear multiple regression technique was employed to determine the parameters of the equations and to choose the best forms with the highest values of R2 and F-ratio which reflect the goodness and the reliability of the fit.  相似文献   

15.
Nonionic surfactants having polydisperse polyoxyethylene chains and highly fluorinated hydrophobes were synthesized via a complex reaction route and their adsorption at water/air interfaces studied. They exhibit high surface activity and decrease both effectively and efficiently the surface tension of their aqueous solutions. The effect of the length of the polyoxyethylene chain upon surfactant surface activity is relatively low. Lower values of surface tension, below 30 mN m?1, are obtained for surfactants having a low degree of ethoxylation. Surfactants having two terminal highly fluorinated hydrophobes are less surface active than analogues with one terminal hydrophobe.  相似文献   

16.
In this study, esterification reaction between four different fatty alcohols (octyl, dodecyl, hexdecyl and octadecyl alcohol) and phosphoric acid was performed. The produced compound was reacted with polyethylene glycol-400. Then, the reaction product was quenched using sodium hydroxide to form the desired anionic gemini surfactants. The chemical structures of the synthesized surfactants were recognized by FT-IR and 1H NMR spectroscopy. The synthesized surfactants showed higher surface activity. The emulsion stability measurements showed the applicability of these surfactants as emulsifying agents. The foaming power measurements showed the synthesized surfactants have low ability to foam formation. The thermodynamic parameters showed their tendency toward adsorption at the interfaces and also micellization in the bulk of their solutions. The studied surfactants were evaluated as antimicrobial agents against pathogenic bacteria using inhibition zone diameters. The synthesized surfactants showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative as well as fungi. The promising inhibition efficiency of these compounds against the pathogenic bacteria facilitates them to be applicable in the petroleum field as new categories of biocides.  相似文献   

17.
The properties of poly(ethylene terephthalate) (PET) and polypropylene (PP) blends and PET/maleic anhydride-grafted PP (MAgPP) reactive blends were investigated. Two blend systems were immiscible based on tan δ measured by dynamic mechanical analyzer (DMA). In case of PET/MAgPP blends, the reaction of ester groups of PET and MA sites on MAgPP occurred during melt mixing at 280°C for 30 min. The reaction was confirmed by a new peak between the glass transition temperatures of PET-rich and MAgPP-rich phase on tan δ curves, as well as from the rheological properties. From the morphology, the improvement of the dispersibility in PET/MAgPP reactive blends was observed. The modulus of PET/MAgPP blends was higher than that of PET/PP blends, and the strength of PET/MAgPP blends showed the good adhesion compared with the PET/PP blends. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 389–395, 1998  相似文献   

18.
A non-fouling (protein resistant) polymer surface was achieved using an argon glow discharge treatment of a polyethylene surface which had been precoated with various poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) (PEO-PPO-PEO) tri-block copolymer surfactants. The surfactant is first deposited on the polymer surface via a solvent swelling and evaporation method. Then the coated surfactant is immobilized on the substrate surface by an inert gas discharge treatment. ESCA and water contact angle () measurements on treated and solvent washed surfaces show significant increases in both surface O/C ratios and surface water wettability (0 < 30°) compared to LDPE control surfaces, revealing the presence of PEO on the treated surfaces. A great reduction of fibrinogen adsorption on the modified surfaces is also observed for the highest PEO content surfactants. This simple surface modification process may have wide applicability to obtain wettable polymer surfaces in general, and non-fouling biomaterial surfaces in specific.  相似文献   

19.
Three cationic surfactants were prepared. A condensation reaction between dimethylaminopropylamine (DMAPA) and benzaldehyde was performed. The produced Schiff base was quaternization with three fatty alkyl bromide with different carbon chain length separately to form the desired cationic surfactants. The chemical structure of synthesized cationic surfactants was confirmed by FTIR, 1H NMR and mass spectroscopy. It was found that the chemical structure of prepared compounds has an effect on surface properties, where increasing the hydrophobic chain length decrease the values of CMC, Гmax while Amin value was increased. The thermodynamic parameters showed that adsorption and micellization processes are spontaneous. It is clear that the prepared cationic surfactants at first tend to adsorb at surface, then it aggregate to form micelle. The prepared surfactants showed good biological activity against gram positive and negative bacteria and fungi in the following order of II (C12) > I (C10) > III (C16). The serial dilution method was used to evaluate the inhibiting effect of these compounds on the sulfate reducing bacteria growth.  相似文献   

20.
An improved suspension polymerization method for preparation of the magnetic poly(methyl acrylate) microspheres (mPMA‐DVB) was investigated. Through subsequent reaction with methyl acrylate (MA) and ethylenediamine (EDA), the magnetic poly(methyl acrylate) microspheres with dendron surface was obtained, and the magnetic poly(methyl acrylate) microspheres with dendron surface reacted with carbon bisulfide and sodium hydroxide to create sodium dithiocarbamate. Following, the resultant magnetic microspheres with dendron surface modification were used to adsorb Au(III) from aqueous solution. The result showed that the capacity of amino groups on the surface of the mPMA microspheres increased from 1.67 mmol/g for the magnetic polymer microspheres with G0 dendron to 4.35 mmol/g with G3 dendron, and the adsorption capacity rose from 0.1981 g/g with G0 dendron to 0.7853 g/g with G3 dendron. The effects of solution pH, the adsorption temperature, the adsorption time, and the initial concentration of Au(III) on the adsorption of Au(III) were studied, the optimum pH for Au(III) adsorption was found at pH = 1, the adsorption capacity achieved the maximum in 60 min, and the adsorption process was endothermic reaction and conformed to pseudo‐second‐order kinetic models. Furthermore, the adsorption process was in accordance with the Langmuir model. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

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