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1.
碳氢/碳氟表面活性剂复配体系溶致液晶的研究   总被引:1,自引:0,他引:1  
以全氟辛酸钠-十六烷基三甲基溴化铵/正丁醇/水体系为研究对象,通过其相图的测定确立了液晶区.其液晶区域面积大于十六烷基三甲基溴化铵/正丁醇/水体系的液晶区.摄制了该体系液晶区系列样品的纹理照片,用小角X光衍射法测定了液晶各种组分变化时的层间距,并结合2HNMR谱图和纹理照片的对照和分析,从分子水平上研究了液晶的微观结构.  相似文献   

2.
AEO-9体系溶致液晶性能及其组成方程   总被引:8,自引:0,他引:8  
以非离子表面活性剂十二烷基醇聚氧乙烯醚(AEO-9)/正丁醇/正辛烷/水组成的四元体系为研究对象,绘制了拟三元相图。在液晶区选取样品点,拍摄纹理照片,并结合^2HNMR谱图确定了液晶类型其中主要是状液晶。利用小角X射线衍射测定了层状液晶的层间距d,得到层间距d和液晶含水量的关系。根据层状液晶结构的特点,推导出层状液晶组成方程,并对本体系进行了验证。结果表明,根据议程计算出的液晶区域的开头和位置与实验测得的相图中液晶的开头和位置基本相同,为实际应用提供了依据。  相似文献   

3.
在非水三元体系(卵磷脂,乙二醇,甲醇)中能得到溶致液晶,其中溶剂必须经过严格的脱水处理,本文使用偏振光显微镜确定溶致液晶的相图,获得一些典型照片,用低角度X射线衍射仪测定其几何参数,结果表明所得液晶为层状液晶,并对在该体系中,由于甲醇浓度的改变而引起了卵磷脂分子的平均截面积、液晶层间距和其渗透率变化规律作了理论探讨和分析。  相似文献   

4.
溶致液晶体系研究及其在三次采油中的应用   总被引:8,自引:0,他引:8  
研究了石油磺酸盐/正戊醇/水的三元体系和石油磺酸盐/癸烷/正戊醇/水的拟三元体系相图中的液晶区域,揭示了不同组分对液晶区域大小的影响以及液晶的流变性和液晶的结构.在三次采油中,用六角状溶致液晶体系代替三元复合驱体系进行化学驱油,虽然驱油效率更高,但需要进一步降低液晶驱油体系的成本.  相似文献   

5.
溶致液晶体研究及其在三次采油中的应用   总被引:4,自引:0,他引:4  
研究了石同磺酸盐/正戊醇/水的三元体系和石油磺酸盐/癸烷/正戊醇/水的拟三元体系相图中的液晶区域,揭示了不同组分对液晶区域大小的影响以及液晶的流变性和液晶的结构,在三次采油中,用六角状溶致液晶体系代替三元复合驱体系进行化学驱油,虽然驱油效率更高,但需进一步降低液晶驱油体系的成本。  相似文献   

6.
在前期建立的溶剂、聚肽、柔性高分子三元体系的理论模型上, 引入外场作用的自由能, 推导了液晶相与非液晶相中各物质的化学位, 研究了外场作用下的聚肽三元体系的相行为. 结果表明外场的作用可使液晶相与非液晶相的两相区域变小, 两相区向低浓度方向移动, 同时柔性高分子可进入液晶相. 此外还研究了外场作用下聚肽的分子链构象、链长和温度等对体系相行为的影响, 并对理论计算与实验结果进行了比较.  相似文献   

7.
泊洛沙姆F127和丹皮酚对GMO液晶相变的影响   总被引:1,自引:0,他引:1  
李超  高缘  张建军  朱家壁  吴莲花 《化学学报》2011,69(13):1503-1508
对GMO/H2O, GMO/F-127/H2O和GMO/paeonol/H2O三种体系的液晶特性进行了考察, 结合粘度及偏光纹理绘制相图, 运用“drying”方法的原理鉴别了反相胶束和立方相液晶, 并采用临界堆积参数p值理论探讨水溶性和脂溶性物质引起液晶相变的机理. 结果表明水溶性泊洛沙姆F127可使层状液晶区域变宽, 立方相液晶区域变窄|脂溶性丹皮酚可使层状液晶和立方相液晶区域变窄, 反相六角相液晶变宽. 本研究通过对单油酸甘油酯(GMO)液晶特征的研究, 为其作为载体的应用提供了理论基础.  相似文献   

8.
以对羟基苯甲酸、对苯二甲酸和对苯二酚为共聚单体,经乙酰化和熔融缩聚两步法合成三元热致液晶共聚酯。引入长链脂肪族化合物1,8-辛二酸作为改性单体,按不同比例代替对苯二甲酸,制备了一系列含柔性链段的新型四元热致液晶共聚酯。通过傅里叶红外光谱(FT-IR)和核磁共振碳谱(13C-NMR)对共聚酯结构进行表征,采用差示扫描量热(DSC)和热失重分析(TGA)表征其热性能,采用偏光显微镜(POM)和X射线衍射(XRD)分析其液晶性能。研究表明,三元液晶共聚酯熔点达407℃,热稳定性优异。随着1,8-辛二酸含量增加,四元共聚酯熔点显著降至214℃,热稳定性较好,最大热分解温度达到428℃。该系列共聚酯显示了典型的向列型液晶织态结构。1,8-辛二酸的引入显著改善了液晶共聚酯的可加工性。  相似文献   

9.
苯酐催化剂表面SEM图象的计算机纹理解析法   总被引:4,自引:0,他引:4  
自Haralick提出计算机纹理分析的统计模型以来,纹理分析技术在遥感图象的识别与分类及细胞显微图象等医用照片的自动诊断上都获得了很好的效果,近年来,它的研究发展很快,并不断地开拓着新的应用领域,本文将这一手段引入表面催化的研究中,以催化剂表面的SEM图象为对象,利用计算机模式识别理论和方法,对催化剂的宏观或亚宏观形貌进行纹理解析,抽取各种表面纹理特征,并将这些特征值与催化剂表面的理化参数相关联,研究了催化剂表面的形成、变迁及其规律。  相似文献   

10.
测定了十二烷基磺酸钠/正戊醇/水体系的相平衡,在相图中的液晶区选取样品点,采用2H NMR和差示扫描量热方法,并结合其液晶纹理,研究了该体系液晶相的结构特点。结果表明,在一定温度下,整个液晶区均为层状液晶,其相结构不随水含量和醇含量的变化而变化。在组成固定的情况下,该体系液晶的相结构随温度的升高而发生变化。  相似文献   

11.
The phase behavior and structure of sucrose ester/water/oil systems in the presence of long-chain cosurfactant (monolaurin) and small amounts of ionic surfactants was investigated by phase study and small angle X-ray scattering. In a water/sucrose ester/monolaurin/decane system at 27 degrees C, instead of a three-phase microemulsion, lamellar liquid crystals are formed in the dilute region. Unlike other systems in the presence of alcohol as cosurfactant, the HLB composition does not change with dilution, since monolaurin adsorbs almost completely in the interface. The addition of small amounts of ionic surfactant, regardless of the counterion, increases the solubilization of water in W/O microemulsions. The solubilization on oil in O/W microemulsions is not much affected, but structuring is induced and a viscous isotropic phase is formed. At high ionic surfactant concentrations, the single-phase microemulsion disappears and liquid crystals are favored.  相似文献   

12.
A biocompatible surfactant-n-dodecylammonium α-glutamate (GDA) with biodegradable and biocompatible properties was synthesized, and the phase behavior and the structural properties of GDA/n-pentanol/water system was studied by small-angle X-ray diffraction, electron spin resonance, and freeze-fracture transmission electron microscopy (FF-TEM). In the ternary phase diagram of GDA/n-pentanol/water system, there exist three isotropic regions—O/W, bicontinuous, and W/O structures, and two anisotropic regions—hexagonal liquid crystal (HEX), and lamellar liquid crystal (LLC) regions. UV irradiation causes the decrease in the interlayer space, d, of lamellar liquid crystal and in the radius, r, of column aggregates of hexagonal liquid crystal, but it has little effect on the structure of O/W and W/O microemulsions.  相似文献   

13.
The ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF4) forms nonaqueous microemulsions with p-xylene, with the aid of the nonionic surfactant TX-100. The phase behavior of the ternary system is investigated, and three microregions of the microemulsions-ionic liquid-in-oil (IL/O), bicontinuous, and oil-in-ionic liquid (O/IL)-are identified by conductivity measurements, according to percolation theory. On the basis of a phase diagram, a series of IL/O microemulsions are chosen and characterized by dynamic light scattering (DLS). The size of aggregates increases on increasing the amount of added polar component (bmimBF(4)), which is a similar phenomenon to that observed for typical water-in-oil (W/O) microemulsions, suggesting the formation of IL/O microemulsions. The microstructural characteristics of the microemulsions are investigated by FTIR and 1H NMR spectroscopy. The results indicate that the interaction between the electronegative oxygen atoms of the oxyethylene (OE) units in TX-100 and the electropositive imidazolium ring may be the driving force for the solubilization of bmimBF4 into the core of the TX-100 aggregates. In addition, the micropolarity of the microemulsions is investigated by using methyl orange (MO) as a UV/Vis spectroscopic probe. A relatively constant polarity of the microemulsion droplets is obtained in the IL microemulsion. Finally, a plausible structure for the IL/O microemulsion is presented.  相似文献   

14.
Photoisomerization of trans-stilbene (TS) was investigated in sodium dodecyl sulfate (SDS)/benzyl alcohol (BA)/H(2)O systems in order to establish the relationship between the reaction yields and the compositions and structures of molecular organized assemblies. The results show that, in SDS/BA/H(2)O systems with the structures of oil in water microemulsions, bicontinuous microemulsions, and hexagonal liquid crystals, the reaction yields are much larger than those in benzyl alcohol, both with and without the photosensitizer 9,10-anthracenedicarbonitrile. However, SDS/BA/H(2)O water in oil microemulsion and lamellar liquid crystal can obviously catalyze the photoisomerization of TS only when the photosensitizer is not present. The yield is increased with the increase in H(2)O content or with the decrease in BA content.  相似文献   

15.
The phase conditions in a system of water, hexadecane, sodium dodecyl sulphate, and di-ethylene glycol dodecyl ether showed theW/O microemulsions to be obtained first after destabilization of a liquid crystalline phase by addition of the hexadecane. The original lamellar liquid crystalline phase was moved towards higher surfactant/cosurfactant ratios and a new phase with inverse amphiphile cylinders in a hexagonal packing appeared.  相似文献   

16.
Triton X-100/C10H21OH/H2O体系微乳液与溶致液晶   总被引:1,自引:0,他引:1  
关于离子型表面活性剂生成的微乳液与溶致液晶已有不少研究,非离子型表面活性剂生成的微乳液与港致液晶的应用正在引起人们的重视,但由于药物提纯的困难,对其物理化学性质的研究还不多见.本文以非离子表面活性剂TritonX-100/C10H21OH/H2O体系为例,研究了非离子型表面活性剂微乳液和溶致液晶的生成及其结构特性.1实验部分试剂ThitonX-100(Aldrich公司,分析纯)正癸醇(分析纯)、水为一次蒸馏水微乳液区域和层状液晶区域的确定方法及小角x射线衍射测定方法同文献,实验温度20±0.1℃.2结果与讨论2·IThtonX-100、CIOH…  相似文献   

17.
Ionic liquid based microemulsions were characterized by absorption solvatochromic shifts, (1)H NMR and kinetic measurements in order to investigate the properties of the ionic liquid within the restricted geometry provided by microemulsions and the interactions of the ionic liquid with the interface. Experimental results show a significant difference between the interfaces of normal water and the new ionic liquid microemulsions. Absorption solvatochromic shift experiments and kinetic studies on the aminolysis of 4-nitrophenyl laurate by n-decylamine show that the polarity at the interface of the ionic liquid in oil microemulsions (IL/O) is higher than at the interface of water in oil microemulsions (W/O) despite the fact that the polarity of [bmim][BF(4)(-)] is lower than the polarity of water. (1)H NMR experiments showed that an increase in the ionic liquid content of the microemulsion led to an increase in the interaction between [bmim][BF(4)(-)] and TX-100. The reason for the higher polarity of the microemulsions with the ionic liquid can be explained in terms of the incorporation of higher levels of the ionic liquid at the interface of the microemulsions, as compared to water in the traditional systems.  相似文献   

18.
微乳液结构的研究   总被引:6,自引:1,他引:6  
测定了十二烷基磺酸钠/正丁醇/20%苯乙烯/水体系的相平衡,用冷冻刻蚀、ESR、FT-IR研究了上述体系微乳液的结构,研究表明,苯乙烯含量恒定时,随着体系中水含量增加,电导确定的双连续结构的微乳液经历着从油包水到以连续再到水包油变化,FT-IR测定表明,W/O微乳兴较O/W微乳液的OH伸缩振动和弯曲振动频率有显著减小,说明W/O微乳兴中氢键缔合要比O/W强得多。ESR测定表明O/W微乳液的旋转相关  相似文献   

19.
本文系统研究了四-(4-苯基磺酸基)卟啉(TPPS)在由聚乙二醇辛基苯基醚(TX-100)构筑的反相微乳液内相中的聚集行为。通过改变反相微乳水相液滴的pH值、粒径及TPPS的浓度,发现在反相乳液内相中TPPS的表观pKa明显小于在水溶液中的pKa(4.9),并且,TPPS的表观pKa随着水相液滴粒径的减小而降低;当水相液滴的pH > pKa时,TPPS以去质子化单体H2TPPS4-形式存在,而当pH < pKa时,TPPS以质子化单体H4TPPS2-和J-聚集两种形式存在,并且TPPS浓度的增大,促进了H4TPPS2-向J-聚集转变;在pH值不变的条件下,随着水相液滴粒径的增大,TPPS的存在状态由H2TPPS4-向H4TPPS2-转变,并形成J-聚集。  相似文献   

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