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1.
A novel homologous series of 1-N-l-phenylalanine-glycerol ether surfactants was synthesized in satisfactory yields via reaction of epichlorohydrin with aliphatic alcohols with alkyl chains of 10–15 carbon atoms. Structural assignment of the new compounds was made on the basis of elemental analysis and spectroscopic data. Critical micelle concentration (CMC), surface tension at the CMC (γCMC), surfactant concentration required to reduce the surface tension of the solvent by 20 mN/m (pC20), and the interfacial area occupied by the surfactant molecules (Amin) were determined from aqueous surface tension measurements using the Wilhelmy plate technique.  相似文献   

2.
Glactomannan gum was isolated from Gleditsia triacanthos seeds. It was then subjected to polymerization with acrylic acid using potassium persulfate initiation system. Products of the polymerization reactions are referred to as composites. Technical evaluation of the latter as thickening agent in reactive printing using cotton fabric was studied. The use of composite in printing cotton fabric with natural dye was also studied. It was found that the composite pastes are characterized by a non‐Newtonian pseudoplastic behavior, and their apparent viscosity increases on increasing the concentration of acrylic acid. The composite can be diluted by water and its viscosity increases by neutralization. Printing pastes of the composite are very stable for storing, in contrast with those of natural gum which exhibit no stability for storing. It was also found that reactive prints thickened with the composite display relatively higher K/S than those thickened with native gum do. Meanwhile, K/S values of prints thickened with the composite are comparable with the values of those thickened with sodium alginate. Printed fabrics using the composite as a thickener exhibit soft handle, and their overall fastness properties are almost equal to, if not higher than, the properties of those printed using sodium alginate. On the other hand, printing of cotton fabric with a natural dye using the composite as a thickener results in prints with K/S values lower than those obtained using commercial synthetic thickener; but the overall fastness properties are nearly the same. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 931–943, 2006  相似文献   

3.
Synthesis and Characterization of some Alkyl Polyglycosides Surfactants   总被引:1,自引:0,他引:1  
Alkyl polyglycosides (APGs) of different hydrocarbon chain lengths were prepared using an indirect method involving the condensation of fatty alcohol with dextrose. The chemical structures of the prepared compounds were confirmed using different spectroscopic techniques, primarily Fourier transform infrared spectroscopy, nuclear magnetic resonance and mass spectroscopy. The surface properties of the solutions containing different concentrations of the prepared APGs were determined at different temperatures. The results of the spectroscopic analysis demonstrate that these materials were prepared through the correct techniques, producing pure materials. The results of the critical micelle concentration (CMC) determination demonstrate that the surface properties of these compounds depend mainly on the nature of their hydrophobic component.
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4.
A novel homologous series of 1-N-l-tryptophanglycerol-ether surfactants was synthesized and characterized. The precursor compounds, 3-alkyloxy-1-chloropropan-2-ols, were prepared from epichlorohydrin and aliphatic alcohols with alkyl chain lengths of 9–16 carbon atoms. Tryptophan was then attached to the monosubstituted glycerol backbone from its α-amino group through an α-NH-C bond. Structural assignment of the new compounds was made on the basis of elemental analysis and spectroscopic data. Critical micelle concentrations of the new surfactants, as well as the negative logs of the surfactant concentrations required to reduce the surface tension of the solvent by 20 mN/m (pC 20) and the interfacial areas occupied by the surfactant molecules, were calculated from aqueous surface tension measurements using the Wilhelmy plate technique.  相似文献   

5.
Polymerizable epoxy resin (PER) surfactants have been prepared from the reaction of bisphenol A epoxy resin with acrylic acid, followed by the reaction with polyethylene glycol (PEG) with different molecular weights. The reaction procedures were monitored by chemical titrations, infrared spectroscopy, and NMR. The products show typical surface‐active properties as but much higher water solubility than nonpolymerizable nonionic surfactant OP‐10. With the increase of PEG's molecular weight, the HLB value, the water solubility, and the critical micellar concentration (CMC) of the PER surfactants, the cloud point of the PER surfactant solutions, as well as the solubilization capability of the PER surfactants to organic compounds increase under the experimental conditions. The copolymerization under UV radiation indicated that about 75–80 wt % of PER surfactants participated in the copolymerization with epoxy diacrylate (EdA), except for the PER surfactant with the lowest PEG molecular weight of 1 k. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42598.  相似文献   

6.
The chemistry of radiation curable polyurethane dispersions is outlined with an emphasis on the microstructure of the aqueous polymer dispersion and the possible interactions with associative thickeners. The steady-shear flow was studied for two model dispersions prepared from the same unsaturated polyurethane but showing significantly different particle size distributions. A hydrophobically modified ethoxylated urethane (HEUR) associative thickener with a linear structure was incorporated at different amounts to the dispersions with varying particle volume fractions. The steady-state viscosity at 25 and 10 °C was always reached quickly after instant flow rate changes so that no significant thixotropic effects were reported within the experimental timescale. Without thickener, the flow curves of the two model dispersions exhibited a Newtonian behavior except at the highest volume fractions where shear thinning became apparent. The maximum packing values determined from the Krieger–Dougherty relationship were essentially the same for the two systems. In the presence of thickener, the flow curves were characterized by a Newtonian plateau followed by a marked shear thinning region even at low particle volume fractions. This behavior typically suggests the formation of a physical network between polyurethane particles and thickener molecules partly adsorbed onto the polymer surface. The zero-shear viscosity of the two dispersions was compared with respect to: (i) particle volume fraction and (ii) particle surface area at different HEUR concentrations. At a given volume fraction, the particle size affects the viscosity of thickened models. As a corollary, a relationship is found between the particles size and the level of thickener required to reach a target viscosity. This study offers practically relevant data in terms of application conditions and provides a better insight into the thickening protocol.  相似文献   

7.
Ling-Yung Wang 《Polymer》2010,51(1):75-5673
A series of novel side-chain liquid-crystalline polymers (SCLCPs) consisting of laterally attached photoluminescent p-quinquephenyl (QQP) pendants with different flexible terminal- and/or side-alkoxy chains were synthesized via atom transfer radical polymerization (ATRP). Homopolymers (HP1-HP3) and block-copolymers (PSP1-PSP3 and PEOP1-PEOP3), where QQP units were copolymerized with styrene or ethylene oxide monomers, possessed the number average molecular weights (Mn) of 8.7-26.0 × 103 with narrow PDI values of 1.08-1.26. Various characterization techniques of polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were used to investigate their mesomorphic properties, and all homopolymers and block-copolymers exhibited the nematic phase affected by the flexible terminal- and/or side-alkoxy chains of the conjugated rod-like pendants. In addition, the photophysical properties of these polymers were measured by UV-vis and photoluminescence (PL) spectroscopies, which showed blue PL emissions with rather high fluorescence quantum yields in solutions.  相似文献   

8.
In this work, acrylic/acrylate copolymeric surfactants, which can be used in the preparation of pesticide oil‐in‐water emulsions (EW), were synthesized by emulsion polymerization, using potassium persulfate (K2S2O8) as an initiator, dodecyl mercaptan (DDM) as a chain transfer agent at the temperature range of 82–85°C. When the weight ratio of monomers was m(butyl acrylate) : m(methyl methacrylate) : m(acrylic acid) = 4 : 4 : 1.6 and the dosage of DDM was 2% (percentage of monomer mass), the prepared acrylic/acrylate copolymeric surfactants had a number‐average molecular weight of 2.5 × 104 and exhibited good stability for pesticide EW. The carboxylic group distribution studies show that only the surface carboxylic groups make dispersed pesticide oil droplets more stable. The acrylic/acrylate copolymeric surfactants prepared by shot‐monomer had the most surface carboxylic group distribution (46.6%). To obtain greater surface carboxylic group distribution, maleic anhydride (MA) was used to modify the polymer system. Adding 2% MA (percentage of monomer mass) to the polymerization system, the surface carboxylic groups were increased 12% over unmodified acrylic/acrylate copolymeric surfactants. Compared with traditional pesticide EW, the avermectin EW prepared with acrylic/acrylate polymeric surfactant had much better stability. Meanwhile, its pesticide effect was similar to that of a control (1.8% abamectin emulsifiable solution). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

9.
The growing concern for the environment is promoting the use of surfactant products from renewable sources such as fatty alcohol ethoxylates. The high production and use of these products implies the need to develop models that enable predictions of their behaviour in biodegradation processes. The biodegradation tests were carried out according to the OECD 301 E test for ready biodegradability. In this work, kinetic models of general application to surfactant biodegradation are developed, both for substrates that do not support growth and for those that do, considering a residual substrate concentration as not being biodegraded. The models were applied to three commercial non-ionic surfactants, fatty alcohol ethoxylates with different carbon-chain lengths and degrees of ethoxylation, also analysing the initial surfactant concentration.  相似文献   

10.
Polymeric organogels based on vinyl phosphonic acid (VPA) and acrylic monomers such as 2-acrylamido 2-methyl propane sulfunic acid (AMPS) and acrylamide (AM) were prepared. The synthesized poly (AMPS-VPA) organgels can absorb ethanol (12.64–31.2 g/g) and methanol (17.65–32.32 g/g). Poly (AM-VPA) can absorb DMSO (4.05–8.94 g/g). TGA analysis showed that thermal stability of organogels was improved with enhancement of VPA content. This was attributed to presence of phosphorus in the polymer structure. Rheological behavior exhibited that gel strength was decreased with higher VPA content in copolymeric structures.  相似文献   

11.
An inverse, free‐radical emulsion polymerization technique was designed for the preparation of copolymers of acrylamide and sodium acrylate modified with low amounts (<0.5 mol %) of a series of amphiphilic comonomers, the isooctylphenoxy–poly(oxyethylene)(n) methacrylates (1 ≤ n ≤ 12). The products of the reaction were hydrophobically modified water‐soluble polymers (HMWSPs) of high molecular weight encapsulated within water droplets dispersed in an organic medium. Kinetic studies showed that the full‐conversion samples were rather homogeneous in composition because of the specificity of the process. A mechanistic scheme is proposed that accounts for the incorporation level of the amphiphilic comonomer as a function of its hydrophile–lipophile balance and the nature of the redox initiator (hydrophilic or lipophilic). The rheological properties of the HMWSPs in aqueous solutions were investigated as a function of the comonomer content and the nature of the initiator with steady‐flow experiments. The thickening properties were directly correlated to the conditions of synthesis and were optimal when the initiator and the amphiphilic comonomer were located in two distinct phases. A maximum in viscosity was observed for a hydrophobe content of about 0.3 mol %. An examination of the viscosity as a function of the shear rate and time showed that these solutions had all the characteristics of associating polymers. The complex rheological behavior was the result of the balance between interchain and intrachain hydrophobic liaisons and the kinetics of disorganization and reorganization of the network structure. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1418–1430, 2002; DOI 10.1002/app.10337  相似文献   

12.
The corrosion inhibition characteristics of non-ionic surfactants of the TRITON-X series, known as TRITON-X-100 and TRITON-X-405, on stainless steel (SS) type X4Cr13 in sulphuric acid were investigated by potentiodynamic polarisation measurements. It was found that these surfactants act as good inhibitors of the corrosion of stainless steel in 2 mol L−1 H2SO4 solution, but the inhibition efficiency strongly depends on the electrode potential. The polarisation data showed that the non-ionic surfactants used in this study acted as mixed-type inhibitors and adsorb on the stainless steel surface, in agreement with the Flory-Huggins adsorption isotherm. Calculated ΔGads values are −57.79 kJ mol−1 for TRITON-X-100, and −87.5 kJ mol−1 for TRITON-X-405. From the molecular structure it can be supposed that these surfactants adsorb on the metal surface through two lone pairs of electrons on the oxygen atoms of the hydrophilic head group, suggesting a chemisorption mechanism.  相似文献   

13.
A series of new cationic surfactants was prepared by condensation of lactic acid with N,N-dimethyl propylamine, followed successively by acetylation with acid chloride or ester and by quaternization with dimethylsulfate. Each surfactant and its precursors' structural assignments were based on infrared spectra and 1H and 13C nuclear magnetic resonance spectra. Critical micelle concentrations, contact angles, kinetics of drop spreading, and foam capacities were determined.  相似文献   

14.
In the present work, a thermal-UV dual-cure process was performed on acrylate–oxetane systems. A 1:1 molar mixture of difunctional acrylate–oxetane mixture was prepared starting from 2,2-Bis(4-(3-acryloxy-2-hydroxypropoxy)phenyl)propane (BPADA) and 3-ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane (OXT-221, DOX). Following a difunctional oxetane-acrylic monomer (OXAC) was synthesized.  相似文献   

15.
甲基丙烯酸甲酯与丙烯酸正丁酯乳液聚合的研究   总被引:1,自引:0,他引:1  
以甲基丙烯酸甲酯与丙烯酸正丁酯为主要原料,过硫酸铵为引发剂,OP-10、十二烷基硫酸钠(K12)为乳化剂,用乳液聚合法合成了聚丙烯酸酯类共聚乳液,考察了聚合条件对乳液聚合的影响。实验结果表明,在单体、引发剂、水用量一定时,合适的反应条件为乳化剂(OP-10∶K12=1∶1)2%,单体滴加时间以60~90min,80℃反应2h左右。  相似文献   

16.
黄旭娟  刘鹤  王磊  商士斌 《化工进展》2016,35(2):575-580
采用环氧大豆油(ESO)为原料,乙酸乙酯为溶剂,四氯化锡为催化剂,通过环氧大豆油的开环自聚,制备聚合环氧大豆油(PESO);再将PESO在碱性条件下水解,洗涤纯化后得到水解聚合环氧大豆油(HPESO)。通过傅里叶红外光谱(FTIR)、核磁共振氢谱(1H NMR)和凝胶渗透色谱(GPC)对HPESO的结构及分子量分布进行了表征,并对得到的水解聚合环氧大豆油脂肪酸钾盐表面活性剂(HPESO-K)的临界胶束浓度cmc及其表面张力(γcmc)、Krafft点(KP)、液体石蜡/水体系的乳化能力(EP)与抑泡及消泡能力(FP)进行了研究。结果表明:HPESO的数均分子量范围为1056~1156g/mol,重均分子量范围为1255~1374g/mol。在水溶液pH值为9~12条件下,HPESO-K的cmc值为0.13~0.41g/L,γcmc值为25.6~31.2mN/m。在水溶液pH=9条件下测得HPESO-K的Krafft点为37℃,液体石蜡/水体系中分出10mL水的时间为130s,亲水亲油平衡(HLB)值范围为10~11。  相似文献   

17.
A series of cationic cleavable surfactants was prepared by condensation of 2-alkyl-1,3-propanediols with 3-bromopropanal, followed by reaction with triethylamine. Each surfactant is a mixture of two diastereomers, and their precursors’ stereochemical assignments were based on1H nuclear magnetic resonance spectra and melting points. The critical micelle concentrations, Krafft points and destructibility of these surfactants were determined.  相似文献   

18.
采用吊片法和鼓气法分别测定两类表面活性剂——肉豆蔻酰基 β-丙氨酸钾/钠(MAP/MAS)和肉豆蔻酰基牛磺酸钾/钠(MTP/MTS)的表面张力和泡沫性能,并研究添加无机盐和有机铵盐对MAS与MTS泡沫性能的影响.结果表明,两类表面活性剂的临界胶束浓度(CMC)与反离子类型相关,MTP的起泡性弱于MTS但稳泡性高于MTS;除四丁基溴化铵(TBAB)外,盐的添加均可显著提升两种表面活性剂的稳泡性,而对起泡性的影响不明显;添加阳离子对两种表面活性剂的泡沫性能的影响与其亲水基类型相关,MTS/盐体系的离子特异性效应比MAS/盐体系更为显著,其稳泡性在添加K+时达到峰值,而MTS/TBAB的消泡性能最为显著.  相似文献   

19.
Poly acrylic siloxane coatings are generating a lot of interest due to their high durability and superior performance properties in different applications. However, synthesis of high siloxane containing acrylic binder through emulsion polymerization is a challenge. Herein, we present a study on the synthesis and characterization of polystyrene-acrylate/polysiloxane core shell latex systems through regular seeded emulsion polymerization. Hybrid polymers have been characterized for their physical, chemical, thermal and surface properties using different characterizing techniques like FTIR, DSC, DMA, SEM, TEM, DLS and contact angle measurements. Incorporation of polysiloxane in the shell of the polymer particle was found to improve hydrophobicity and mechanical properties. Exterior paints prepared using the hybrid polymers as binders exhibited superior performance properties like weather ability and dirt pick up resistance.  相似文献   

20.
The fluorinated polyacrylate latex were successfully prepared with semi- continuous seeded emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and hexafluorobutyl methacrylate (HFMA) which was initiated with potassium persulfate (KPS) initiator and emulsified with the novel mixed surfactants of sodium lauryl glutamate (SLG) and alkylphenol ethoxylates (OP-10). The structure of the resultant latex was confirmed by Fourier transform infrared spectroscopy (FTIR). The particle size of the latex was measured by Zetatrac dynamic light scattering detector. The film of latex was tested by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and contact angle (CA). The optimum conditions of preparing the novel fluorinated polyacrylate latex are optimized and the results are as follows: the amount of emulsifiers is 4.0%; mass ratio of SLG to OP-10 is 1:1, the amount of the initiator is 0.6%. The mass ratio of MMA to BA is 1:1 and the amount of HFMA is 7.0%. In this case, the conversion is high and the polymerization stability is good. In addition, the water resistance and thermal properties of the latex films were improved significantly in comparison with the film of the latex prepared without the fluorinated monomer.  相似文献   

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