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1.
改进了Pouchly提出了的Flory-Huggins半经验展开式,详细推导了盯应的三元相图中双结点溶解度曲线(Binodal线)和亚稳均相极限线(Spinodal线)的议程;计算了非溶剂和溶剂的相互作用参数g12,溶剂和醋酸纤维素的相互作用参数g23同时依浓度变化的三元相图。:的Flory-Huggins方程更具有普适性。  相似文献   

2.
田洛阳  陈亚丽  王强 《应用化学》2017,34(7):824-832
在343.15~373.15 K温度范围内,采用反气相色谱法(IGC)测试了18种有机溶剂在离子液体1-丁基-3-甲基咪唑六氟磷酸盐([BMIM]PF6)中的热力学参数。在测试温度范围内计算了有机溶剂与[BMIM]PF6之间的摩尔吸收焓、质量分数活度系数、Flory-Huggins相互作用参数、偏摩尔混合焓和无限稀释活度系数等热力学参数。结果表明,所选的有机溶剂中,正构烷烃、环己烷、四氢呋喃、乙醚和四氯化碳为[BMIM]PF6的不良溶剂。 相比之下,苯、甲苯、间二甲苯、二氯甲烷、丙酮、氯仿、乙酸乙酯、乙酸甲酯、乙醇和甲醇是[BMIM]PF6的良溶剂。  相似文献   

3.
李晓萍  王强  李玲  丁艳萍 《色谱》2015,33(1):58-64
采用反气相色谱法(IGC)表征了离子液体(IL)1-己基-3-甲基咪唑四氟硼酸盐([HMIM]BF4)在343.15~373.15 K温度范围内的热力学参数.使用了一系列不同化学结构的探针分子测定[HMIM]BF4与溶剂之间的相互作用力.根据探针分子的保留时间计算得到探针分子与[HMIM]BF4之间的Flory-Huggins相互作用参数、摩尔吸附焓、无限稀释摩尔混合焓、摩尔蒸发焓、无限稀释活度系数以及[HMIM]BF4的溶解度参数.结果表明,n-C6n-C7n-C8n-C9、乙醚、四氢呋喃、苯、环己烷为[HMIM]BF4的不良溶剂;甲苯、间二甲苯、甲醇、乙醇、二氯甲烷、四氯化碳、氯仿、丙酮、乙酸乙酯、乙酸甲酯为[HMIM]BF4的良溶剂.运用外推法得到了[HMIM]BF4在室温(298.15K)时的溶解度参数为23.70 (J·-3)0.5.实验结果证明反气相色谱法是一种简便准确的获得离子液体热力学参数的方法.获得的热力学参数体现了这种离子液体与探针分子之间的相互作用力.本研究为离子液体的进一步应用提供了参考.  相似文献   

4.
本文以NaCl-CaCl2-SrCl2三元计算相图作为“预知图形”,采用高灵敏度的微型差热分析仪,测定该三元相图是三元低共晶体系,其低共晶点E的组成(百分摩尔)为NaCl41.9%,CaCl240.0%,SrCl218.1%,温度为744K。  相似文献   

5.
本文包括两部分内容:(1)运用三元系的Flory-Huggins公式,测定二苯甲酮与二苯胺的相互作用参数;(2)以联苄为参考溶剂,测定某些芳烃与络合溶剂二苯甲酮的分  相似文献   

6.
黄玲  周效贤  郑国康 《化学学报》1997,55(7):659-664
测量了角鲨烷(B)+邻苯二甲酸二丁酯(C)的溶解度相图, 应用HSFH二元系公式推算得相互作用参数Abc; 用气-液色谱测量了若干正构烷烃、环烷烃用作探测溶质(A)在(B+C)混合溶剂中的无限稀活度系数, 应用HSFH三元系公式推算得相互作用参数Abc, 两者符合热力学一致性。  相似文献   

7.
实验绘制了十二烷基硫酸钠(SDS)/正戊醇(n-C5H10OH)-二甲苯[C6H4(CH3)2]-水[或Zn(NO3)2溶液]四组分微乳液体系在不同温度时的拟三元相图. 测定了电导率随水(或盐溶液)含量变化的规律, 电导的规律与相图吻合. 依据电解质理论探讨了微乳液的微观结构, 研究表明, 温度对油包水(W/O)反相微乳液区域影响不大, 电解质的加入对油包水(W/O)反相微乳液区域影响较大. 通过SDS/正戊醇-二甲苯-H2O及SDS/正戊醇-二甲苯-盐水的拟三元体系的相图观察及实验研究, 选择乳化剂(SDS/正戊醇)与二甲苯质量比为4:6的微乳液作为最佳条件, 制备出了ZnO纳米粒子.  相似文献   

8.
邓丽霜  王强  张正方  唐军 《色谱》2014,32(2):169-173
采用反气相色谱法研究了343.15~373.15 K温度范围内离子液体1-己基-3-甲基咪唑三氟甲磺酸盐([HMIM]OTF)的热力学参数。根据18种探针溶剂的保留时间计算出探针溶剂与[HMIM]OTF之间的摩尔吸附焓、无限稀释的摩尔混合焓、摩尔蒸发焓、质量部分活度系数、Flory-Huggins相互作用参数及[HMIM]OTF的溶解度参数。结果表明,所选溶剂中正构烷烃、四氢呋喃、乙醚、环己烷和苯为[HMIM]OTF的不良溶剂;二氯甲烷、丙酮、氯仿、乙酸乙酯、四氯化碳、乙酸甲酯、甲苯和甲醇为[HMIM]OTF的良溶剂;运用外推法得到了室温(298.15 K)时[HMIM]OTF的溶解度参数为20.74 (J/cm3)0.5。本研究为离子液体的应用及相关工作提供了参考。  相似文献   

9.
利用红外光谱研究了NaNO3和NaClO4在N,N-二甲基甲酰胺(DMF)溶剂中发生离子-溶剂和离子-离子的相互作用, 分析结果表明, DMF的OC-N谱带发生了明显的变化. 定量计算了在Na+浓度为0.22~1.24 mol/kg范围内的溶剂化数为1~4. 对谱图中酰胺基上C-N和CO的特征峰强度随Na+浓度变化的对比, 推测离子溶剂化作用导致DMF的酰胺基内部形成共轭键. 利用量子化学方法进行优化及热力学性质计算, 得到C-N键伸缩振动频率及红外光谱强度变化规律. 优化结构与实验结论相符合. 由NaNO3的ν2谱带及NaClO4的ν1谱带的解析得到溶液中阴离子缔合效应的一般规律, 并通过阴离子缔合特征峰与酰胺基上的N-C-N面外振动峰(865 cm-1)的变化情况, 讨论了溶液中的离子溶剂化作用.  相似文献   

10.
本文根据定标粒子溶液理论计算了KCl、KBr、NaCl、NaBr、CsCl和CsBr在DMSO、DMF、MeOH、(CH3)2CO、MeCN、EtOH和H2O中的溶剂化自由能,涉及的离子-溶剂间静电相互作用能,用“一层连续介质模型”所给出的公式计算,结果与实验符合很好。  相似文献   

11.
A new molecular thermodynamic model is developed for multicomponent Ising lattice based on a generalized nonrandom factor from binary system. Predictions of the nonrandom factor and the internal energy of mixing for ternary and quaternary systems match accurately with simulation results. Predictions of liquid-liquid phase equilibrium for ternary systems are in nearly perfect agreement with simulation results, and substantially improved from Flory-Huggins theory and the lattice-cluster theory. The model also satisfactorily correlates the experimental data of real ternary systems. The concise expression and the accuracy of the new model make it well suited for practical engineering applications.  相似文献   

12.
To elucidate induced smectic A and smectic B phases in binary nematic liquid crystal mixtures, a generalized thermodynamic model has been developed in the framework of a combined Flory-Huggins free energy for isotropic mixing, Maier-Saupe free energy for orientational ordering, McMillan free energy for smectic ordering, Chandrasekhar-Clark free energy for hexagonal ordering, and phase field free energy for crystal solidification. Although nematic constituents have no smectic phase, the complexation between these constituent liquid crystal molecules in their mixture resulted in a more stable ordered phase such as smectic A or B phases. Various phase transitions of crystal-smectic, smectic-nematic, and nematic-isotropic phases have been determined by minimizing the above combined free energies with respect to each order parameter of these mesophases. By changing the strengths of anisotropic interaction and hexagonal interaction parameters, the present model captures the induced smectic A or smectic B phases of the binary nematic mixtures. Of particular importance is the fact that the calculated phase diagrams show remarkable agreement with the experimental phase diagrams of binary nematic liquid crystal mixtures involving induced smectic A or induced smectic B phase.  相似文献   

13.
The influence of copolymer configuration on the phase behavior of various ternary polymer blends containing a crystallizable polyester, a noncrystallizable polyether, and an acrylic random copolymer of different chain configuration was investigated. In these ternary blends, the acrylic random copolymer is typically added to control rheological properties at elevated temperatures. In fact, the acrylic random copolymers composed of various compositions of MMA and nBMA were found to have different miscibility with polyester as well as polyether, leading to substantially different phase behavior of ternary blends. Remarkable temperature dependence was also found. The mean-field Flory-Huggins theory for the free energy of mixing, extended to ternary polymer blends, was adopted for predicting phase diagrams where the exact spinodal and binodal boundaries could be calculated. Phase diagrams of ternary blends, predicted by the Flory-Huggins formulations and related calculations, were in good agreement with experimental phase diagrams. The differences observed in the rheological processes of various ternary blends with different acrylic copolymers were directly related to changes in miscibility, associated phase behavior, and chain configuration.  相似文献   

14.
含无规共聚物共混体系的相容性研究正在成为近年来的研究热点 ,因为相容的驱动力来自共聚物分子内不同单体链段间的排斥性相互作用 [1~ 3] .目前研究这类体系还主要采用过份简化的 F- H平均场理论 ,用旨在克服平均场理论缺陷的 Flory状态方程 ( EOS)理论仅局限于研究二元共聚物共混体系[4~ 8] .与三元共混体系相比 ,用 EOS理论预测含两个无规共聚物三元体系相行为尚需确定共聚物 -共聚物间的二元参数 sj/si,Xij和 Qij.若用 Ax B1- x和 Cy D1- y分别代表共聚物 1和 2 ,则 A,B,C,D代表相应共聚物中的单体单元 ,x,y分别是 1和 2的共…  相似文献   

15.
本文测定了一些溶质在一些二元固定液串联柱、多相柱与均相柱的比保留体积,应用三元体系的Flory-Huggins公式以及两种不同溶剂的Flory-Huggins型相互作用参数数据,揭示了溶质在这些柱中比保留体积异同的热力学原因.  相似文献   

16.
Vapor–liquid equilibrium data for the difluoromethane (R32) + pentafluoroethane (R125) + propane (R290) ternary mixture were measured at 5 isotherms between 263.15 K and 323.15 K. The measurement was carried out using a circulation-type apparatus recently developed, which was validated with binary mixtures. With binary interaction parameters obtained for the three corresponding binary mixtures, VLE modeling and prediction were performed for the ternary mixture using the Peng–Robinson equation of state with the classical mixing rules and MHV1 mixing rules. Hou's group contribution model for VLE of new refrigerant mixtures was further tested with the experimental data for the ternary system. The predicted pressure and vapor phase composition were compared with experimental ones.  相似文献   

17.
18.
We propose a new theoretical scheme for the binary phase diagrams of crystal-liquid crystal mixtures by a combination of a phase field model of solidification, the Flory-Huggins theory for liquid-liquid mixing and Maier-Saupe-McMillan (FH-MSM) model for nematic and smectic liquid crystal orderings. The phase field theory describes the crystal phase transition of anisotropic organic crystal and/or side chain liquid crystalline polymer crystals while the FH-MSM model explains isotropic, nematic and smectic-A phase transitions. Self-consistent calculations reveal several possible phase diagram topologies of the binary crystal-liquid crystal mixtures. The calculated phase diagrams were found to accord well to the reported experimental results.  相似文献   

19.
A truly miscible ternary miscible blend consisting of poly(?‐caprolactone) (PCL), poly(phenyl methacrylate), and poly(benzyl methacrylate) (PBzMA) was discovered. The three‐polymer blend system was completely miscible within the entire composition range at ambient temperature up to about 150 °C, and ternary phase diagrams at increasing temperatures were characterized and interpreted. A ternary‐interaction model based on the modified Flory–Huggins expression was used to describe the phase diagrams with the individual binary interaction strengths. The model fitted well with the experimental‐phase diagram for the ternary blend system at T = 250 °C, where the binary PCL‐PBzMA blend system is on the critical points of phase separation. Interpretation of discrepancy between the model and experimental at other temperatures was handled with an empirical approach. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 747–754, 2002  相似文献   

20.
A method for predicting isobaric binary and ternary vapor—liquid equilibrium data using only isothermal binary heat of mixing data and pure component vapor pressure data is presented. Three binary and two ternary hydrocarbon liquid mixtures were studied. The method consists of evaluating the parameters of the NRTL equation from isothermal heat of mixing data for the constituent binary pairs. These parameters are then used in the multicomponent NRTL equation to compute isobaric vapor—liquid equilibrium data for the ternary mixture. No ternary or higher order interaction terms are needed in the ternary calculations because of the nature of the NRTL equation. NRTL parameters derived from heat of mixing data at one temperature can be used to predict vapor—liquid equilibrium data at other temperatures up to the boiling temperature of the liquid mixture.For the systems studied this method predicted the composition of the vapor phase with a standard deviation ranging from 1–8% for the binary systems and from 4–12% for the ternary systems.  相似文献   

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