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1.
The lamellar liquid crystalline phase in the system consisting of sodium oleate (NaOL), oleic acid (OLA), and water was determined. The interlayer spacing (d) of the lamellar liquid crystal was measured through small angle X-ray diffraction, which indicated that oleic acid molecules were solubilized between the end methyl groups at low concentrations, and then were located within the hydrocarbon chain layer with further increase of its concentration. Cross-linking agents were added to the system, which were found being located partly in between the end methyl groups and partly within the hydrocarbon chain layers. The liquid crystal phase of NaOL/OLA/H2O system with the cross-linking agent was polymerized at 60 °C, which turned out to be a mixture of liquid crystals and solids. Interlayer spacing decreased by about 10 Å, indicating a disruption of the ordered structure by the polymerization. The polymerization took place not only within the hydrocarbon layer, but also in between the layers separated by the end methyl groups. The resulting polymer lowered the surface tension of water to below 30 mN/m, with a critical micellization concentration of about O.25g/L.  相似文献   

2.
将十六烷增溶于油酸钠/水体系层状液晶的油层,共聚单体二乙烯基乙二醇增溶于油酸钠/水体系层状液晶的两亲层,将共聚限制在同一两亲层内油酸钠的双键与共聚单体之间进行。得到了具有层状结构,并具有较好表面活性的共聚物。  相似文献   

3.
油酸/三乙醇胺/液体石蜡水体系层状润滑性能   总被引:3,自引:0,他引:3  
采用^2HNMRT和IR,表征了油酸/三乙醇胺/液体石蜡/水体系层状液晶的结构,并以该体系为润滑剂,测定了其在铝合金表面的磨痕宽度和摩擦系数,同时与液体石蜡和商用润滑剂12-羟基硬脂酸锂进行了比较。结果表明,OLA/TEA/LP/H2O体系丑状液晶具有较好的极压性能,对于铝合金材料是一种较好的润滑剂。  相似文献   

4.
5.
赵继宽  陈晓 《化学学报》2007,65(9):803-808
以非离子表面活性剂四氧乙烯基正十二烷基醚与氯铂酸水溶液构建层状溶致液晶, 通过电沉积技术制备了金属铂纳米线. 分别采用偏光显微镜、小角X射线散射对液晶进行结构分析, 通过透射电镜和能量弥散X射线谱分析观测产物形貌并确定其组成. 结果表明, 相对于饱和甘汞电极, 沉积电势在0.05~0.20 V范围内, 金属铂沿表面活性剂双分子层膜生长, 反应前后液晶相的长程周期性结构无明显变化; 在0.10 V沉积电势下, 随反应时间从960 s延长至3840 s, 去除表面活性剂后沉积产物分别为层状纳米粒子、层状纳米线以及长度达十几微米且致密的纳米线. 讨论了层状液晶对沉积产物的结构导向作用.  相似文献   

6.
SDS H2O-C4H9OH体系层状液晶的结构及增溶作用   总被引:5,自引:2,他引:5  
表面活性剂溶液中关于胶束和微乳的形成及性质已有大量研究~[1]. 近年来表面活性剂分子所形成的层状液晶的结构和它的增溶. 渗透、扩散作用的研究引起了广泛的关注~[2,3,4]. 它的性质和结构的研究在实际与理论上皆有很大的意义, 特别是在生物体系中显得十分重要. 本工作利用小角度X射线衍射研究了SDS(sodium dode-cyl sulfate)-H_2O-C_4H_9OH体系层状液晶的结构及增溶C_7H_(16)后对结构的影响, 并对本体系中两亲分子在液晶中的排列和增溶的机制提出相应的看法。  相似文献   

7.
The influence of SDS (a hydrotrope) on the region of stability of a microemulsion of water, sodium dodecyl sulfate (SDS), pentanol (C3OH) and p-xylene was determined. The addition of the hydrotrope united the O/W and W/O regions of the phase diagram enlarging the bicontinuous region by reducing the lamellar liquid crystal one. Hence, the phase behavior and the low angle x-ray measurements show that the stratum corneum coupling action of a hydrotrope is in  相似文献   

8.
The partial phase diagram of the Triton X-100/C10H21OH/H2O system was determined. PbS nanoparticles were synthesized in solvent layer of Triton X-100/C10H21OH/H2O lamellar liquid crystal. The size of PbS nanoparticles was about 8 nm and limited by the thickness of the solvent layer. Lubricities of the mixed system of Triton X-100/C10H21OH/H2O lamellar liquid crystal and PbS nanoparticles were determined. The results showed that the lamellar liquid crystal and the mixed system showed higher load carrying capacity relative to the commercial grease. They are potential lubricants for Al alloy, especially at high load.  相似文献   

9.
Triton X-100体系层状液晶结构及其润滑性能   总被引:1,自引:0,他引:1  
用小角X射线衍射和^2HNMR方法测定TritonX-100/n-C10H21OH/H2O体系层状液晶的结构。用高速环块磨损试验机考察了不同组分含量的层状液晶对铝合金-钢磨擦副润滑性能的影响。结果表明:随着水含量的增加,层次液晶两新双层中分子的有序度降低,润滑效果也降低;随着TritonX-100含量增加,层状液晶两亲双层中分子的有序度增加,其润滑效果提高。  相似文献   

10.
用小角X射线衍射和2HNMR方法测定TritonX 100/n C10H21OH/H2O体系层状液晶的结构.用高速环块磨损验机考察了不同组分含量的层状液晶对铝合金 钢磨擦副润滑性能的影响.结果表明:随着水含量的增加,层液晶两亲双层中分子的有序度降低,润滑效果也降低;随着Tri tonX 100含量增加,层状液晶两亲双层中分子有序度增加,其润滑效果提高.  相似文献   

11.
Order character and lamellar structure of TritonX 100/n C10H21OH/H2O lamellar liquid crystal were investigated. Partial phase diagram of TritonX 100/C10H21OH/H2O was measured at 25℃ by the polarizing microscope, and lamellar structure of the lamellar liquid crystal was verified by the 2H NMR spectra. The ESR spin probe method was used to detect the changes in the lamellar liquid crystal. A stearic acid, 5 doxylstearic acid, was used as the spin probe. The values of hyperfine coupling constant and order parameter of lamellar liquid crystal in the phase diagram were calculated. The values of the hyperfine coupling constant with different composition were almost unchanged. It indicates that the micropolarity of the lamellar liquid crystal is very similar. The order parameter decreases with the increasing water content in lamellar liquid crystal. It can be explained by considering that: First, though the penetration is determined at the given weight ratio of C10H21OH to TritonX 100, the absolute water content penetrated into the amphiphile bilayer increases with the increasing of the water content. Second, the thickness of the solvent also increases, which makes the force between layers weaker. The results also showed that order parameter of lamellar liquid crystal increased with TritonX 100 content, which may be explained from the fact that the water content penetrated into the amphiphile bilayer decreases relatively and the molecules in the amphiphile bilayer are made tighten. The interlayer spacing of lamellar liquid crystal was determined by small angle X ray diffraction. The penetration ratio of water in the lamellar liquid crystal was calculated. It was about 50%.  相似文献   

12.
以烯丙基溴,对羟基苯甲酸和对氰基苯酚为主要原料,通过Williamson和酯化反应合成了一种新型的具有反应活性的液晶基元——对烯丙氧基苯甲酸对氰基苯羟酯(1),产率60.1%,其结构经1H NMR和IR表征。DSC,热台偏光显微镜和X-射线衍射分析表明,1具有液晶性,介晶区间为81℃;在升温及降温过程中呈现出的扇形织构隶属于近晶C晶型,为互变双向性液晶基元。  相似文献   

13.
溶剂性质对层状液晶结构与稳定性的影响   总被引:3,自引:0,他引:3  
郭荣 《高等学校化学学报》1991,12(11):1526-1528
水体系层状液晶虽早有研究,但对非水层状液晶的研究则开始较晚,本文用HNMR和小角X射线衍射等方法,研究了极性有机溶剂甲酰胺代替水后,对SDS/C10OH/溶剂体系层状液晶结构与稳定性的影响。  相似文献   

14.
十二烷基硫酸钠中相微乳液的液晶结构   总被引:1,自引:0,他引:1  
微乳液是指油、水、表面活性剂、助表面活性剂形成的各向同性的、光学透明或半透明的热力学稳定体系.中相微乳液是指富表面活性剂相与过剩水相、过剩油相形成的三相体系.中相微乳液既可增溶水,又可增溶油,且与过剩水相、油相超低的界面张力,因而在强化采油中引起人们...  相似文献   

15.
16.
Regulating the aqueous polymerization of acrylic acid (AA) is a major opportunity for future materials design, requiring the development of scalable, industry‐oriented procedures that afford modest molar mass and dispersity control without long reaction times and environmentally demanding conditions. To address these challenges, this report presents the rapid copolymerization of aqueous mixtures of AA and sodium acrylate using an inexpensive and scalable protocol based on alkyl iodides/sodium iodide as mediators in water. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1414–1419  相似文献   

17.
Unit cell constants were determined from powder X-ray diffraction photographs taken of several anhydrous short-chain sodium alkanoates at room temperature. The temperature dependence of the bilayer spacing in the alkanoates was determined over the range 25-300°C. Overall changes in bilayer spacings between the solid and the neat phase were found to be much smaller than in long-chain alkanoates. A correspondence was noted between the room temperature lateral packing area and the 23Na quadrupole coupling constant in the mesophase. The mcsophase bilayer spacing was consistent with a structural model in which the tilted anion chain rotates on a cone.  相似文献   

18.
The mechanism of copolymerization of vinyl chloride (V) with sulfur dioxide (S) to form a variable composition polysulfone with average V:S molar ratio n ≥ 1 is examined. The copolymerization deviates from Lewis-Mayo behavior above -78°C. Alternative models for propagation involving (1) penultimate and pen-penultimate unit effects, (2) complex participation, and (3) depropagation are considered quantitatively by comparison of calculated and experimental copolymer/comonomer composition relationships and comonomer sequence distributions. Our theoretical modeling of the copolymerization shows that it is difficult to discriminate convincingly between alternative mechanisms. The penultimate and pen-penultimate effect models can account for the copolymer compositions, but not for the dilution effects which were observed provided the diluent is truly inert. The complex participation model can account for experimental behavior from -78 to -18°C by the assumption of addition of SV complexes, but it becomes rapidly less satisfactory at higher temperatures. Depropagation is the only model which can account for the compositions and dilution effects above 0°C. Progressive depropagation, with increasing temperature, of chains ending in the triad sequences ~SVS?, ~VVS?, and ~VSV? can explain the observed behavior over the entire comonomer composition and temperature range, but involvement of comonomer complexes in the propagation reactions is highly likely below 0°C.  相似文献   

19.
丙烯酸与海藻酸钠共聚制备耐盐性高吸水树脂   总被引:22,自引:0,他引:22  
丙烯酸与海藻酸钠共聚制备耐盐性高吸水树脂  相似文献   

20.
The copolymerization of isoprene or butadiene with acrylonitrile in the presence of zinc chloride or ethylaluminum sesquichloride, in the presence or absence of a free radical catalyst, at 30-70°C yields an equimolar, diene-acrylonitrile alternating copolymer containing more than 90% trans-1,4 unsaturation, irrespective of monomer charge. The copolymer results from the homopolymerization of a diene-acrylonitrile…metal halide transoid charge transfer complex. When ZnCl2 is the electron-accepting metal halide and the polymerization is carried out at temperatures of 50°C and higher or to high conversions, the equimolar copolymer is accompanied by a high acrylonitrile polymer, and in the presence of a radical catalyst, by a normal radical copolymer. In the presence of the organoaluminum halide and in the absence of a radical catalyst, the alternating copolymer is the only product, irrespective of monomer charge. However, in the presence of a radical catalyst and at high acrylonitrile monomer charges, e.g., D/AN = 10/90, the alternating copolymer is accompanied by a normal radical copolymer. The formation of equimolar, alternating copolymer at all monomer ratios and in the absence or presence of a radical catalyst indicates that the (D-AN…MX) charge transfer complex readily undergoes homopolymerization and does not copolymerize with free diene or acrylonitrile or with the AN-AN…MX complex.  相似文献   

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