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以丙酮、 异丙醇和苯为溶剂在超临界状态下对煤直接液化残渣进行萃取, 应用溶度参数分析了超临界萃取环境中溶剂和萃取原料的变化; 基于Hansen拓展方法建立了关联Hansen溶度参数和萃取收率的理论方程. 结果表明, 临界温度较高. 以色散力溶度参数为主的苯的萃取收率明显高于其它2种溶剂; 液化残渣中可萃出组分的理想溶解度随温度的升高而增大, 该效应也是超临界溶剂萃取重质组分时萃取收率提高的重要原因; 萃取收率与Hansen溶度参数之间的回归模型与实验结果具有较好的一致性, 证明Hansen溶度参数理论和Hansen拓展方法适用于描述煤直接液化残渣的超临界萃取过程.  相似文献   

3.
Dispersions of single-walled carbon nanotubes in various solvents and aqueous surfactant emulsions were investigated to correlate the degree of dispersion state with Hansen solubility parameters (deltat2=deltad2+deltap2+deltah2). It was found that the nanotubes were dispersed or suspended very well in the solvents with certain dispersive component (deltad) values. They were precipitated in the solvents with high polar component (deltap) values or hydrogen-bonding component (deltah) values. The solvents in the dispersed group occupied a certain region in a 3-dimensional space of three components. The surfactants with a lipophilic group equal to and longer than decyl, containing 9 methylene groups and 1 methyl group, contributed to the dispersion of nanotubes in water. The surfactants in the dispersed group had a lower limit in the dispersive component (deltad) of the Hansen parameter.  相似文献   

4.
Solubility parameters are certain measurable quantities that are observed to influence the ability of a solvent to fully dissolve a polymer. Current theory partitions the intermolecular forces between dispersion, polar, and hydrogen bonding interactions, thereby generating a three‐dimensional solubility parameter space. The Hansen solubility parameters of a polymer are taken to be the center of a sphere obtained from the best fit of the coordinates of good solvents in the parameter space. Investigations of several polymers (lignin, polyethersulfone, and bitumen) show that the convex hull of all known good solvents in the three‐dimensional parameter space also gives a meaningful interpretation of the solubility region. Several methods for computing the convex solubility parameters of a polymer from the convex solubility region are described. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1089–1097  相似文献   

5.
本文研究了聚甲基丙烯酸三丁基锡酯(PTBTM)和聚甲基丙烯酸三甲基锡酯(PTMTM)在约六十种溶剂中的溶解性能。测定了它们在不同性质溶剂中的特性粘数,订定了PTBTM和PTMTM的溶度参数。并就有机锡聚合物中锡原子上的取代基对其溶解性能的影响进行了讨论。  相似文献   

6.
The influence of various physical and chemical factors on the swelling of polystyrene and PEG based resins in greener organic solvents has been systematically investigated. In general, chemical factors: the nature of the functionality/linker and the degree of loading were found to have a far larger influence on the swelling of the resins than physical parameters such as bead size. The results are interpreted in terms of Hansen solubility parameters for the solvents and there is evidence that some solvents interact with the polymeric core of a resin whilst others interact with the functionality. The results are extended to a study of the changes in resin swelling observed during both deprotection and chain elongation reactions during solid phase peptide synthesis.  相似文献   

7.
An investigation on the effect of sulfonic group on solubility parameters and solubility behavior of poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) is presented. Sulfonated PPO (SPPO) was prepared using chlorosulfonic acid as a sulfonating agent. The structure of SPPO was confirmed by FT‐IR, and the ion exchange capacity (IEC) of SPPO was accurately determined by conductometric titration and 1H‐NMR. The three‐dimensional solubility parameters of SPPO defined by Hansen were estimated by group contribution, and this approach was used to obtain the three coordinates of a solubility parameter in terms of: a dispersion part δd, a polar part δp and a hydrogen bonding part δh. The theoretical predications of solubility behavior were characterized using “soluble sphere” in three‐dimensional space. The estimated results were in accordance with the solubility experiments in different solvents. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

8.
Some organic compounds gelate particular solvents by forming a network of anisotropic fibres. We show that Hansen solubility parameters can be used to predict the range of solvents that are likely to be gelled by any given gelator.  相似文献   

9.
The sorbent–eluent systems combined from eight polymeric sorbents and seven solvents as eluents were used for the extraction of phenol and its oxidation products from water samples. The individual interactions between sorbents, eluents and analytes were characterized by Hansen solubility parameters. Principal components analysis (PCA) was used for revealing the dominant interactions (dispersive, polar, and hydrogen bonding type) in sorbent–analyte–eluent systems. The importance of solubility parameters was also determined by a novel procedure based on sum of ranking differences (SRD). Although PCA and ranking by SRD are based on different principles and calculations, they have provided very similar results. The recovery in a given system has been predicted from the magnitudes of mutual interactions (sorbent–analyte, sorbent–eluent, analyte–eluent) by multiple linear regression.  相似文献   

10.
The phase behavior of some rodlike block molecules has been reviewed with reference to the polarity of constituent segments. It was found that the ability of the mesophase formation is connected with differences in polar character between the flexible chains and rigid cores. Thus the polar poly(oxyethylene) group connected with the polar rigid core reduces mesophase stability but is advantageous when put together with some apolar building blocks. An attempt at quantitative estimation of the incompatibilities of different parts of molecules by means of Hansen solubility parameters delta and Flory interaction parameters chi has also been made. On the basis of chi parameters the Gibbs free energies of mixing of these segments were calculated. The changes of Gibbs free energy reflecting the compatibility of segments and their tendency to the phase separation and the volume fraction of mesogenic rigid core reflecting their ability to arrangement in one direction appear to be crucial in terms of type of the mesophase formation.  相似文献   

11.
应用溶解度参数理论筛选柴油萃取脱蜡的溶剂   总被引:6,自引:0,他引:6  
采用基团贡献法分别计算了酮类、氯代烃类、酯类、醇类和醚类溶剂的色散溶解度参数(δd)、极性溶解度参数(δp)和氢键溶解度参数(δh),并分析了柴油组分中正构烷烃和芳烃的三维溶解度参数的特点。研究了溶剂溶解度参数与其萃取柴油脱蜡效果的关系。结果表明,除了醇类溶剂之外,在参数贡献图中距离正构烷烃距离越远的溶剂,正构烷烃得率越大,萃取效果越好;色散力贡献比大于2/3的溶剂萃取时蜡膏的含油量明显低于色散力贡献比小于2/3的溶剂。  相似文献   

12.
用基团贡献法估算聚砜、聚醚砜及其磺化产物的溶度参   总被引:4,自引:0,他引:4  
采用基团贡献法对聚醚砜、聚聚砜及其不同磺化度磺化产物的溶度参数分量δd、δp和δh进行了估算,提出了计算其任意磺化度产物的溶度参数的通式,同时补充了砜基和1,2,4-三取代苯基的基团贡献值Fdi,Fpi和Ehi并提出了计算聚合物溶度参数极性分量(δp)的数学模型,估算得到的结果与文献中的实验结果相吻合。  相似文献   

13.
The solubility behavior of pimozide in individual solvents ranging from nonpolar to highly polar was studied. For understanding the solute-solvent interactions, the partial solubility parameters concept was utilized. Solutions containing excess drug were shaken in a water bath for 72 hours at 25 °C. After the solutions attained equilibrium, they were filtered and analyzed for drug content. A multiple regression method, using extended Hansen’s partial solubility parameters, was applied to verify the solubilities of pimozide in pure polar and nonpolar solvents and to predict its solubility in untested solvents. The three-parameter approach and the Flory-Huggins size correction term ‘B’ give predictions of solubilities with correlations up to 97%. The four-parameter approach involving proton-donor and proton-acceptor parameters was also used in fitting the solubility data. The correlations are appreciable (94%). Further, the ‘B’ term coupled with four-parameter approach was examined in order to improve the data representation, and resulted in a 1% improvement (98%) in the correlation when compared to the Flory-Huggins size-correction method. The solubility parameter obtained by this method is 10.43 H which is closer to the values obtained by theoretical methods, such as Fedors’ and Hoy’s. The resulting partial solubility parameters are δ 2d =8.85 H, δ 2p =2.17 H, δ 2a =3.15 H, and δ 2b =4.08 H, which give insights into the interaction capability of pimozide and are consistent with its chemical structure. Pimozide is a Lewis base as its δ 2b >δ 2a . The total solubility parameter of pimozide is assigned at 10.43 H. This work demonstrates for the first time the validity of the four-parameter approach coupled with the Flory-Huggins size-correction term and therefore the result is interesting.  相似文献   

14.
The partial solubility parameters: An equation-of-state approach   总被引:3,自引:0,他引:3  
The division of the well-known solubility parameter into its dispersion, polar, and hydrogen-bonding components has significantly upgraded its capacity and usefulness in the screening and selection of the appropriate solvents in Industry and in Laboratory. This work presents a new statistical thermodynamic approach for the estimation of these partial components over a broad range of temperature and pressure. Key to this approach is the development of explicit expressions for the contribution of dispersion, dipolar, and hydrogen-bonding interactions to the potential energy of the fluid. The approach is applicable to ordinary solvents, to supercritical fluids, as well as to high polymers. Information on various thermodynamic properties of fluids is used in order to estimate the three solubility parameter components. Extensive tables with the key parameters are presented. On the other hand, available information on these separate components is exploited in order to extract information for the thermodynamic behaviour of the fluids over an extended range of external conditions.  相似文献   

15.
Wang Q  Chen Y  Liu R  Shi Y  Zhang Z  Tang J 《色谱》2011,29(11):1118-1121
采用反相气相色谱(IGC)技术测定了高密度聚乙烯(HDPE)在303.15~343.15 K温度范围内的溶解度参数(δ2)及相关指标。以正己烷(n-C6)、正庚烷(n-C7)、正辛烷(n-C8)、正壬烷(n-C9)、三氯甲烷(CHCl3)及乙酸乙酯(EtAc)作为探针分子溶剂,经计算获得了探针溶剂的比保留体积(V0g)、摩尔吸收焓(ΔHS1)、无限稀释摩尔混合焓(ΔH∞l)、摩尔蒸发焓(ΔHv)、无限稀释活度系数(Ω∞1)以及探针溶剂与HDPE的Flory-Huggins相互作用参数(χ∞1,2)等指标。结果表明,上述6种探针溶剂在测定温度范围内均为HDPE的不良溶剂。此外,还推导出了HDPE在室温(298.15 K)下的溶解度参数δ2为19.00 (J/cm3)0.5。  相似文献   

16.
The solubility behavior of poly(vinylidene fluoride) (PVDF) in about 50 liquids was investigated. The results were input to a computer program to obtain a three-dimensional representation of the polymer solubility region in the Hansen space; the values of dispersion, hydrogen bonding, and polar components of the total solubility parameter δt,P were evaluated. The latter was also estimated from limiting viscosity number data in the eight solvents found. Both experimental methods gave δt,P values in very good agreement. Comparisons among our findings, the literature, and calculated results are discussed.  相似文献   

17.
Elastomer swelling and Hansen solubility parameters   总被引:4,自引:0,他引:4  
The prediction of how much an elastomer swells in contact with a given solvent is important in many industrial processes. In this article, Hansen solubility parameters (HSP) of two EPDM elastomers and one FKM elastomer were determined before vulcanisation by correlating solubility in those solvents that fully dissolved the polymers. These values were then used to generate plots of solvent swelling after the same elastomers were vulcanised. HSP correlations were also established for the same vulcanised elastomers at different levels of swelling. This makes its possible to predict the swelling of the elastomers studied in contact with many untested solvents.  相似文献   

18.
The swelling of resins (Merrifield and HypoGel 200) in mixtures of two solvents was generally found not to vary linearly with the relative amount of each solvent in the mixture. Hansen solubility parameter (HSP) space could be used to define high, medium and low swelling regions for each resin. The variation of resin swelling with binary solvent composition could then be explained based on the HSP parameters of the two solvents and the way in which the line connecting the points corresponding to the two pure solvents bisected the swelling region for the resin. The applicability of the methodology was demonstrated by showing that an appropriate mixture of two green solvents was more effective for solid-phase peptide synthesis on Merrifield resin than use of either individual solvent and could completely replace the use of traditional polar aprotic and chlorinated solvents for this application. It was also shown that the high resin swelling area of Merrifield resin can be used to predict mixtures of green solvents that will dissolve linear, unfunctionalised polystyrene.  相似文献   

19.
The solubility of dehydroabietic acid in (−)-α-pinene, p-cymene, (−)-β-caryophyllene, (−)-α-pinene + p-cymene, (−)-β-caryophyllene + p-cymene and (−)-α-pinene + (−)-β-caryophyllene were determined using the laser monitoring method at atmospheric pressure. The solubility of dehydroabietic acid was positively correlated with temperature from 295.15 to 339.46 K. (−)-α-pinene, p-cymene, and (−)-β-caryophyllene were found to be suitable for the solubilization of dehydroabietic acid. In addition, the non-random two liquid (NRTL), universal quasi-chemical (UNIQUAC), modified Apelblat, modified Wilson, modified Wilson–van’t Hoff, and λh models were applied to correlate the determined solubility data. The modified Apelblat model gave the minor deviation for dehydroabietic acid in monosolvents, while the λh equation showed the best result in the binary solvents. A comparative analysis of compatibility between solutes and solvents was carried out using Hansen solubility parameters. The thermodynamic functions of ΔsolH0, ΔsolS0, ΔsolG0 were calculated according to the van’t Hoff equation, indicating that the dissolution was an entropy-driven heat absorption process. The Conductor-like Screening Model for Real Solvents (COSMO-RS) combined with an experimental value was applied to predict the reasonable solubility data of dehydroabietic acid in the selected solvents systems. The interaction energy of the dehydroabietic acid with the solvent was analyzed by COSMO-RS.  相似文献   

20.
Hansen solubility parameters (HSPs) were established by Hansen in 1967 and predict miscibility between different material systems. So far, HSP theory works across polymers, crystalline bulk solids and nanomaterials and can be used to identify single solvents or, more likely, blends of solvents that deliver not only the initial solubility but also control it during reaction processes. This minireview summarizes the recent progress on HSP theory to optimize dispersion, exfoliation, synthesis, and device fabrication of inorganic nanomaterials. First, we briefly introduce HSP theory and determination of HSPs. Then, we discuss in detail the utilization of HSPs for inorganic nanomaterials, focusing on carbon nanomaterials, two-dimensional non-graphene nanomaterials, and metal oxide nanoparticles. Finally, challenges and perspectives of HSP theory in inorganic nanomaterials are reviewed.  相似文献   

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