The study of interactions between surfactant and salt in aqueous solutions has attracted significant interest in recent years because of their widespread applications and relatively complex behavior.This work reports ...The study of interactions between surfactant and salt in aqueous solutions has attracted significant interest in recent years because of their widespread applications and relatively complex behavior.This work reports the systematic study of surface phenomenon and self-aggregation behavior of cationic surfactant cetyltrimethyl ammonium bromide(CTAB)with ammonium nitrate(NH_(4)NO_(3))salt.Surface and thermodynamic properties of cationic surfactant CTAB with NH_(4)NO_(3)were investigated at different temperatures using different techniques such as conductometry and surface tensiometery.The surface tension measurement was carried out to find out the critical micelle concentration,free energy of adsorption,free energy of micellization,minimum area per molecule,and surface excess concentration.The study reveals that the process of micellization is spontaneous and exothermic in nature.Conductance measurement was carried out to determine critical micelle concentration,degree of ionization and degree of counter ion binding.Addition of NH_(4)NO_(3)to the surfactant solutions increase the values of degree of ionization and degree of counter ion binding,although it lowers the values of critical micelle concentration showing that the process of micellization is more favorable and spontaneous.The study is very helpful to develop better understanding about interaction between electrolyte and surfactant,which are used in many applications and in different processes(e.g.,pharmaceutical,industrial foaming,drug solubilization,oil recovery,and medium for metal nanoparticle formation).展开更多
A tri-quaternary ammonium salt cationic surfactant was synthesized.Its structure was confirmed by using Fourier-transform infrared spectroscopy,^(1)H nuclear magnetic resonance spectroscopy,and X-ray photoelectron spe...A tri-quaternary ammonium salt cationic surfactant was synthesized.Its structure was confirmed by using Fourier-transform infrared spectroscopy,^(1)H nuclear magnetic resonance spectroscopy,and X-ray photoelectron spectroscopy analyses.Three model surfaces,including Au-CH_(3),Au-OH and Au-COOH,were fabricated.Adsorptions of surfactant on the three model surfaces and subsequent plasma proteins adsorption were investigated by quartz crystal microbalance with dissipation(QCM-D).The mass of surfactant on the Au-COOH surface was the largest,followed by that on the Au-CH_(3)surface,and that on the Au-OH surface.These results suggested that the main driving force of surfactant immobilization was electrostatic interaction followed by hydrophobic interaction.Based on the results obtained,we concluded that the protein mass adsorbed on Au-CH_(3)-S,Au-OH-S,and Au-COOH-S surfaces depended on the protein size and orientation.The mass and thickness of S on the Au-COOH surface is the largest and the protein adsorption capacity of Au-COOH-S surface is inferior to that of Au-CH_(3)-S.The Au-COOH-S surface could inhibit lysozyme adsorption,maintain the adsorption balance of bovine serum albumin,and induce fibrinogen-binding protein adsorption.展开更多
A series of monomeric pyridi-quaternary ammonium salt surfactants were prepared with pyridine as raw material.The surface activity of these compounds was determined.At the same time acting with four bacterial strains,...A series of monomeric pyridi-quaternary ammonium salt surfactants were prepared with pyridine as raw material.The surface activity of these compounds was determined.At the same time acting with four bacterial strains,bactericidal ability was studied by the bactericidal rate,MIC and MBC.The results indicate that they have surface activity and bactericidal ability at some certain extent.展开更多
采用二甲基长链烷基叔胺、环氧氯丙烷为主要原料,在盐酸水溶液条件下,"一锅法"合成系列1,3-二(烷基二甲基氯化铵)异丙醇双子季铵盐〔m-3(OH)-m(m=C_8、C_(10)、C_(12)、C_(14)、C_(16)、C_(18))〕;以熔点检测m-3(OH)-m型双子...采用二甲基长链烷基叔胺、环氧氯丙烷为主要原料,在盐酸水溶液条件下,"一锅法"合成系列1,3-二(烷基二甲基氯化铵)异丙醇双子季铵盐〔m-3(OH)-m(m=C_8、C_(10)、C_(12)、C_(14)、C_(16)、C_(18))〕;以熔点检测m-3(OH)-m型双子季铵盐纯度;以C12-3(OH)-C12为例,采用FTIR、1HNMR对其结构进行表征;分别测定不同浓度下各化合物表面张力,0.1%(质量分数)水溶液下的起泡能力、乳化能力。结果表明,随着m的变化,各化合物表面活性、起泡能力及乳化能力均呈现规律性变化;按照m=C_8、C_(10)、C_(12)、C_(14)、C_(16)、C_(18)的顺序,化合物CMC分别为0.09、0.075、0.03、0.024、0.026、0.14 mmol/L,γCMC分别为54.01、32.56、25.74、29.41、30.51、30.28 m N/m;起泡能力和起泡稳定性分别在m=C_(10)及m=C_(12)表现出较好效果;乳化能力在m=C14时效果较好。展开更多
文摘The study of interactions between surfactant and salt in aqueous solutions has attracted significant interest in recent years because of their widespread applications and relatively complex behavior.This work reports the systematic study of surface phenomenon and self-aggregation behavior of cationic surfactant cetyltrimethyl ammonium bromide(CTAB)with ammonium nitrate(NH_(4)NO_(3))salt.Surface and thermodynamic properties of cationic surfactant CTAB with NH_(4)NO_(3)were investigated at different temperatures using different techniques such as conductometry and surface tensiometery.The surface tension measurement was carried out to find out the critical micelle concentration,free energy of adsorption,free energy of micellization,minimum area per molecule,and surface excess concentration.The study reveals that the process of micellization is spontaneous and exothermic in nature.Conductance measurement was carried out to determine critical micelle concentration,degree of ionization and degree of counter ion binding.Addition of NH_(4)NO_(3)to the surfactant solutions increase the values of degree of ionization and degree of counter ion binding,although it lowers the values of critical micelle concentration showing that the process of micellization is more favorable and spontaneous.The study is very helpful to develop better understanding about interaction between electrolyte and surfactant,which are used in many applications and in different processes(e.g.,pharmaceutical,industrial foaming,drug solubilization,oil recovery,and medium for metal nanoparticle formation).
基金the National Natural Science Fundamental Committee of China and HI-Tech Research and the Development Program(863,No.2006AA02Z291)of China.
文摘A tri-quaternary ammonium salt cationic surfactant was synthesized.Its structure was confirmed by using Fourier-transform infrared spectroscopy,^(1)H nuclear magnetic resonance spectroscopy,and X-ray photoelectron spectroscopy analyses.Three model surfaces,including Au-CH_(3),Au-OH and Au-COOH,were fabricated.Adsorptions of surfactant on the three model surfaces and subsequent plasma proteins adsorption were investigated by quartz crystal microbalance with dissipation(QCM-D).The mass of surfactant on the Au-COOH surface was the largest,followed by that on the Au-CH_(3)surface,and that on the Au-OH surface.These results suggested that the main driving force of surfactant immobilization was electrostatic interaction followed by hydrophobic interaction.Based on the results obtained,we concluded that the protein mass adsorbed on Au-CH_(3)-S,Au-OH-S,and Au-COOH-S surfaces depended on the protein size and orientation.The mass and thickness of S on the Au-COOH surface is the largest and the protein adsorption capacity of Au-COOH-S surface is inferior to that of Au-CH_(3)-S.The Au-COOH-S surface could inhibit lysozyme adsorption,maintain the adsorption balance of bovine serum albumin,and induce fibrinogen-binding protein adsorption.
文摘A series of monomeric pyridi-quaternary ammonium salt surfactants were prepared with pyridine as raw material.The surface activity of these compounds was determined.At the same time acting with four bacterial strains,bactericidal ability was studied by the bactericidal rate,MIC and MBC.The results indicate that they have surface activity and bactericidal ability at some certain extent.
文摘采用二甲基长链烷基叔胺、环氧氯丙烷为主要原料,在盐酸水溶液条件下,"一锅法"合成系列1,3-二(烷基二甲基氯化铵)异丙醇双子季铵盐〔m-3(OH)-m(m=C_8、C_(10)、C_(12)、C_(14)、C_(16)、C_(18))〕;以熔点检测m-3(OH)-m型双子季铵盐纯度;以C12-3(OH)-C12为例,采用FTIR、1HNMR对其结构进行表征;分别测定不同浓度下各化合物表面张力,0.1%(质量分数)水溶液下的起泡能力、乳化能力。结果表明,随着m的变化,各化合物表面活性、起泡能力及乳化能力均呈现规律性变化;按照m=C_8、C_(10)、C_(12)、C_(14)、C_(16)、C_(18)的顺序,化合物CMC分别为0.09、0.075、0.03、0.024、0.026、0.14 mmol/L,γCMC分别为54.01、32.56、25.74、29.41、30.51、30.28 m N/m;起泡能力和起泡稳定性分别在m=C_(10)及m=C_(12)表现出较好效果;乳化能力在m=C14时效果较好。
