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1.
Gemini双季铵盐表面活性剂性能优异但生物和化学降解性差,在Gemini双季铵盐表面活性剂结构中引入酯基官能团可以提升产物性能。酯基Gemini双季铵盐表面活性剂含有酯基和双季铵盐基,具有高表面活性、吸附、絮凝、抗盐、湿润、乳化、杀菌防腐和易生物分解等优点,应用前景广阔。本文综述了酯基Gemini双季铵盐表面活性剂的合成路线、性能和石油化工的应用状况,结合发展需求对酯基Gemini双季铵盐表面活性剂的未来发展进行了分析和展望。  相似文献   

2.
双烷链阳离子表面活性剂的合成与定量分析   总被引:21,自引:0,他引:21  
以N,N-二甲基烷基叔胺和α,ω-二溴烷烃为原料,无水乙醇为溶剂合成阳离子型Gemini表面活性剂。反应产物以混合剂乙酸乙酯/乙醇重结晶纯化后,用红外光谱和核磁共振进行结构分析;以溴酚蓝为指示剂、二氯乙烷为分散相的两相化学滴定法测定其含量。结果表明:7种已合成的阳离子型Gemini的活性物含量均在97.5%以上。  相似文献   

3.
分别将Gemini型单体1,3-双(二甲基十四烷基溴化铵)-2-丙烯酰氧基丙烷(14G)或1,3-双(二甲基十六烷基溴化铵)-2-丙烯酰氧基丙烷(16G)与丙烯酰氧乙基三甲基氯化铵(DAC, D)共聚合反应, 合成了新型含Gemini表面活性剂结构单元的两亲性阳离子聚电解质(D14G和D16G). 采用稳态荧光、电导、动态光散射及透射电镜等手段研究了这些聚电解质在水溶液中的聚集行为. 结果表明, 临界聚集浓度(CAC)随着Gemini型表面活性剂单元含量的增加而减小, 同时随着Gemini型表面活性剂单元中疏水碳链长度的增加而降低. 这些聚电解质在水溶液中同时存在分子内和分子间两种类型的聚集体, 而且碳链越长, 形成分子内聚集体的倾向越强. 随着Gemini表面活性剂单元含量的增加, D14G溶液中聚集体的流体动力学半径(Rh)也有所增大, 而D16G溶液中的聚集体的流体动力学半径(Rh) 却略有减小.  相似文献   

4.
本文报道了用碱熔试剂(氢氧化钠-醋酸钠熔融混合物)在封管内进行霍夫曼降解反应,以TAMA和DDMA为对象,研究最佳反应条件,得到高产率的α-烯烃。最佳反应条件为160℃,碱熔试剂为样品量的25倍,反应2小时,为GC测定阳离子表面活性剂亲油基分布提供了可行的分析方法。  相似文献   

5.
梁亚琴  胡志勇  曹端林 《化学通报》2014,77(11):1076-1082
氨基酸基Gemini表面活性剂因具有高表面活性、独特的流变性能和优异的生物相容性等诸多优点受到科研工作者的青睐。本文按照氨基酸类型和亲水基种类对其进行归纳和总结,综述了氨基酸基Gemini表面活性剂的合成、性能和应用研究进展,指出开发简单合成步骤制备新型结构的高光学纯度的氨基酸基Gemini表面活性剂、探讨手性碳原子的立体构型对于其自组装行为的影响是今后的研究重点。  相似文献   

6.
Gemini表面活性剂合成进展   总被引:46,自引:0,他引:46  
系统总结了近百种Gemini表面活性剂的合成路线和方法,并且按照其结构特点分门别类地进行比较和归纳,对今后Gemini表面活性剂的合成发展方向提出了一些看法,这对促进此类新颖表面活性剂的工业化进程将具有指导意义。  相似文献   

7.
三聚氰胺的共振散射光谱分析   总被引:3,自引:1,他引:2  
在pH 3.8的醋酸盐缓冲溶液中,三聚氰胺(MA)可与阴离子表面活性剂十二烷基苯基磺酸钠(SDBS)形成稳定的缔合物微粒.该缔合物微粒体系在472 nm处存在较强的共振散射峰.三聚氰胺浓度在1.0-23.3 mg/L范围内与472 nm处共振散射光强度成线性,检出限为32μg/L MA.研究了共存物质对SDBS共振散射测定三聚氰胺的影响,方法的选择性比较好,应用于合成废水测定,结果满意.  相似文献   

8.
以1,4-环己二醇、氯乙酰氯、长链叔胺(RN(CH_3)_2,R=10、12、14、16)为原料,合成了一系列不同长度烷基链的双酯基型Gemini表面活性剂(分别命名为C10-EG-10、C12-EG-C12、C14-EG-C14、C16-EG-C16),用FTIR、NMR(~1H、~(13)C)对中间体及产物进行了表征,并研究了表面活性剂的表面性能及抑菌能力。结果表明:在298.15K时,采用铂金环法测定了合成的4种不同长度烷基链Gemini表面活性剂的临界胶束浓度,C10-EG-C10、C12-EG-C12、C14-EG-C14、C16-EG-C16的CMC值分别为5.495、1.096、0.186、0.045 mmol·L~(-1),与传统单链季铵盐表面活性剂相比,合成的Gemini表面活性剂具有较低的CMC值。胶束化热力学参数结果表明在形成胶束过程中是自发放热的。对合成的4种表面活性剂进行了乳化性能、起泡性能和抑菌测试,C14-EG-C14表面活性剂具有很好的乳化能力;C16-EG-C16 Gemini表面活性剂具有良好的稳泡能力;C10-EG-C10表面活性剂具有良好的抑菌能力。  相似文献   

9.
丙烯酞胺-烯丙基磺酸钠共聚物(PASA)优良的絮凝性能已在前文[1]中报道.本文主要考察阴离子表面活性剂R12SO3Na对其溶液粘度的影响,并与PAM做了对照.  相似文献   

10.
α,α′-二溴代烷基酮与环状共轭二烯烃(环戊二烯,呋喃)在金属钐粉和磺化亚铜(10%)作用下,高产率地得到[3 4]环加成产物。与开链共轭二烯烃作用没能得到环加成产物,却高产率地得到α,α′-二溴代烷基酮自身偶合产物环戊烯酮衍生物。  相似文献   

11.
通过电化学方法将4,7-二苯基-1,10-邻菲罗啉二磺酸黄盐(DPS)的Cu(Ⅱ)络阴离子掺入聚吡咯(PPy)薄膜内,制成PPy/(DPS)2CuH2O2传感器,该传感器对H2O2的电还原过程有明显催化作用,催伦电流和H2O2浓度在5.0×10^-6~1.0×10^-3mol/L,范围内呈良好性关系,用于模拟样品中H2O2的测定。  相似文献   

12.
靛蓝二磺酸钠褪色分光光度法测定水中臭氧   总被引:1,自引:0,他引:1  
在pH 2.0的磷酸-磷酸氢二钠缓冲溶液中,臭氧可使靛蓝二磺酸钠溶液褪色,且褪色程度与臭氧含量呈线性关系,据此提出了测定水中臭氧的方法。试验结果表明:靛蓝二磺酸钠的最大吸收波长为610 nm,臭氧的质量浓度在0.12~3.0 mg.L-1范围内与吸光度变化值呈线性,表观摩尔吸光率为1.8×104L.mol-1.cm-1。应用此方法测定了水中臭氧的含量,测得相对标准偏差(n=20)在0.6%~2.8%之间。  相似文献   

13.
The water-soluble Cu+chelator bathocuproine disulfonate (BCS) is widely used to quantify Cu+ or detect Cu+ formation in Cu2+-initiated oxidation reactions. The dichlorofluorescin (DCFH) assay is commonly used to monitor free radical reactions, reactive oxygen species (ROS), or reactive nitrogen species (RNS). Upon oxidation the non-fluorescent DCFH is converted into the fluorescent compound dichlorofluorescein (DCF). In the present communication we show that the Cu+ reagent BCS strongly facilitated the oxidation of DCFH in the presence of Cu2+ or Cu+. In contrast, 2,2′-dipyridyl (DP), which is also a Cu+-complexing reagent, but not as well known and therefore not as commonly used as BCS, did not cause any oxidative modification of DCFH in the presence of Cu2+ or Cu+. We therefore recommend that DP should be used instead of BCS to complex Cu+ in reactions which are initiated by Cu2+ and when ROS/RNS are analyzed by the DCFH oxidation assay.  相似文献   

14.
十六烷基二苯醚二磺酸钠表面化学性质及胶团化作用   总被引:3,自引:0,他引:3  
用滴体积法通过表面张力的测定, 系统地研究了十六烷基二苯醚二磺酸钠(C16-MADS)在不同温度(298.0~318.0 K)和不同NaCl浓度(0~0.50 mol•L-1)下的表面活性. 结果表明, 温度升高使C16-MADS溶液的临界胶束浓度(cmc)略有增大, 表面极限吸附量(Γ)降低. cmc随NaCl浓度的增大从1.45×10-4 mol•L-1降至4.10×10-5 mol•L-1, 但最低表面张力(γcmc)基本不受影响. 在298.0 K与303.0 K时, NaCl浓度的增大, Γ增大; 在308.0、313.0与318.0 K时, NaCl浓度的增大, 出现了Γ从2.27 μmol•m-2降低至1.41 μmol•m-2的“反常”现象. 胶团形成自由能(ΔGm0)随温度和NaCl浓度增加负值增大(-63.98~-76.20 kJ•mol-1), 胶团的形成主要是熵驱动过程.  相似文献   

15.
十六烷基二苯醚二磺酸钠分子有序聚集体的研究   总被引:2,自引:0,他引:2  
采用芘为荧光探针、二苯甲酮为猝灭剂,以分子荧光探针法首次测定了由刚性基团联接的特殊双亲水基型阴离子表面活性剂——十六烷基二苯醚二磺酸钠(C16-MADS)的胶束聚集数(Nm),并考察了表面活性剂浓度、无机盐浓度和温度对Nm的影响。结果表明,表面活性剂的浓度必须高于临界胶束浓度(cmc)一个数量级时,才能测定出较为合适的Nm;随着C16-MADS浓度的增大,Nm增大,胶束内核的微极性变小;而温度对Nm的影响极小。与传统的单亲水基阴离子表面活性剂相比,C16-MADS的有序聚集体表现出许多不同之处,如Nm仅为传统的单亲水基阴离子表面活性剂胶束聚集数的一半,无机盐浓度对Nm的影响极小,胶束内核的微极性明显增大。  相似文献   

16.
The three‐dimensional coordination polymer poly[[bis(μ3‐2‐aminoacetato)di‐μ‐aqua‐μ3‐(naphthalene‐1,5‐disulfonato)‐hexasilver(I)] dihydrate], {[Ag6(C10H6O6S2)(C2H4NO2)4(H2O)2]·2H2O}n, based on mixed naphthalene‐1,5‐disulfonate (L1) and 2‐aminoacetate (L2) ligands, contains two AgI centres (Ag1 and Ag4) in general positions, and another two (Ag2 and Ag3) on inversion centres. Ag1 is five‐coordinated by three O atoms from one L1 anion, one L2 anion and one water molecule, one N atom from one L2 anion and one AgI cation in a distorted trigonal–bipyramidal coordination geometry. Ag2 is surrounded by four O atoms from two L2 anions and two water molecules, and two AgI cations in a slightly octahedral coordination geometry. Ag3 is four‐coordinated by two O atoms from two L2 anions and two AgI cations in a slightly distorted square geometry, while Ag4 is also four‐coordinated by two O atoms from one L1 and one L2 ligand, one N atom from another L2 anion, and one AgI cation, exhibiting a distorted tetrahedral coordination geometry. In the crystal structure, there are two one‐dimensional chains nearly perpendicular to one another (interchain angle = 87.0°). The chains are connected by water molecules to give a two‐dimensional layer, and the layers are further bridged by L1 anions to generate a novel three‐dimensional framework. Moreover, hydrogen‐bonding interactions consolidate the network.  相似文献   

17.
In aqueous alkali, Fremy’s salt (potassium nitrosodisulfonate dimer), homolyses nearly exclusively to the monomer radical anion, nitrosodisulfonate (NDS). In this media, NDS almost quantitatively oxidizes benzyl alcohol (PhCH2OH) to benzaldehyde (PhCHO), itself being reduced to hydroxylamine disulfonate (HNDS). The reaction is very nearly first-order in [NDS], [alkanol] and in [OH]. However, with progressive addition of HNDS, decay kinetics of NDS gradually deviates from first-order. Ultimately, with sufficient excess of HNDS, the reaction becomes second-order in [NDS]. The consumption ratio, (ΔPhCH2OH]/Δ[NDS]), is ∼2. PhCD2OH manifests a large primary kinetic isotope effect (kH/kD = 11.6). Substituted benzyl alcohols (RBzCH2OH) with R-groups withdrawing electron density from the O–H bond accelerated the reaction; those with R-groups donating electron density to the O–H bond retarded the reaction. The conversion of 2-propanol to 2-propanone is much slower compared to that of benzyl alcohol to benzaldehyde. An alpha-H atom transfer mechanism seems logical.  相似文献   

18.
A simple, green and efficient protocol for the one‐pot four‐component synthesis of pyrano[2,3‐c ]pyrazole derivatives produced from reaction between aryl aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate in the presence of nano magnetic piperidinium benzene‐1,3‐disulfonate was synthesized in water at 60 °C. The Fe3O4@SiO2 nanoparticle‐supported IL was designed and synthesized. The present process offers advantages such as clean reaction, short reaction time, good to excellent yield, easy purification and easy recoverable catalyst.  相似文献   

19.
1,3-二噁烷环的双磺酸盐表面活性剂的微波合成   总被引:2,自引:0,他引:2  
在微波辐射下, 以磷钨酸为催化剂, N,N-二甲基甲酰胺为溶剂, 将2,2-二羟甲基-1,3-丙二醇与醛缩合合成了单缩醛, 然后与氢化钠和1,3-丙磺内酯反应得到含1,3-二噁烷环的双磺酸盐表面活性剂. 产物经过元素分析、IR和1H NMR表征.  相似文献   

20.
Fu NN  Zhang HS  Ma M  Wang H 《Electrophoresis》2007,28(5):822-829
A novel near-infrared (NIR) cyanine 1-(epsilon-succinimidyl-hexanoate)-1'-methyl-3,3,3',3'-tetramethyl-indocarbocyanine-5,5'-disulfonate potassium (MeCy5-OSu) has been developed in our laboratory. Simultaneous determination of MeCy5-OSu-derivatized polyamines spermine (Spm), spermidine (Spd), cadaverine (Cad), and putrescine (Put) based on the separation by CE combined with diode LIF detection has been accomplished. The highest derivatization efficiency was achieved in 0.2 mol/L borate buffer (pH 8.8) for 20 min at 25 degrees C. Polyamine derivatives were separated within 14 min in the phosphate running buffer (pH 3) containing 50 mmol/L phosphoric acid, 40 mmol/L SDS, and 35% methanol v/v. Linearity of response was obtained in the range of 10-200 nmol/L. The detection limits (S/N = 3) for Spm, Spd, Cad, and Put were 0.8, 1, 3, and 2 nmol/L, respectively. The proposed method has been successfully applied to the analysis of polyamines in erythrocytes of two healthy persons and one cancer patient. Average recoveries for erythrocyte samples were 93.6-106% and coefficients of variation ranged from 1.8 to 5.4%. The analysis of polyamines in erythrocytes can be used for studying the relationship between their changes and the carcinogenesis process involved in erythrocytes.  相似文献   

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