Self-assembling of fullerene C<Subscript>60</Subscript> into (C<Subscript>60</Subscript>)<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> clasters in aromatic solvents

Self-assembling of fullerene C₆₀ into (C₆₀) _n clusters in aromatic solvents was studied. The role of the π-π interactions and dispersion forces in the (C₆₀) _n cluster formation in these media is demonstrated using the data on the solubility of fullerene C₆₀ in these solvents and their ionization potentials and also spectral characteristics of fullerene C₆₀ in the range of 326–340 nm in different solvents.     

Studies on Systems of Salts and Mixed Solvents. XXVI. Solubility and Solvation Behaviour of Aluminium(III) Chloride in Mixed Aqueous Organic Solvents

Using sections of 25°C solubility isotherms of 14 systems of the type AlCl₃? H₂O-organic solvent the investigations are intended to illustrate the possibility of qualitative interpretation of the solubility data on the basis of empirical solvent parameters. Within the group of solvents according to the Kolthoff classification a largely analogous influence on the solubility of aluminium chloride has been noticed. Similarities result from the typical influence on the solvation state of AlCl₃. The results obtained from the solubility investigations and parageneses of the solid phases correlate with the results of spectroscopic investigations. Solid phases so far not observed are reported.     

Thermodynamic properties of solutions of fullerene C<Subscript>60</Subscript> in mixtures of tetraline with carbon tetrachloride and 1,2-dichlorobenzene

The solubility of fullerene C₆₀ in tetraline-carbon tetrachloride and tetraline-1,2-dichlorobenzene systems in all compositions of the mixed solvent are measured in the temperature range of 298.15–338.15 K. It is found that in a mixture of tetraline with 1,2-dichlorobenzene, the solubility of C₆₀ is considerably higher than in its pure components; in this case, solubility has a maximum in the range of lower temperatures and compositions of the mixture X _trl = 0.3–0.5. It is established that C₆₀ forms crystal solvates with components of the mixed solvents. Enthalpies and temperatures of incongruent melting of the crystal solvates are determined by differential scanning calorimetry.     

Estimation of the Gibbs energy of C60 fullerene solution in organic solvents based on the additive group method

The literature data on the Gibbs energy of C₆₀ fullerene dissolution in organic solvents of different classes are analyzed. The contributions of the functional groups (-CH₃,-CH₂-, >CH-, >C<,-OH,-Ph,-Napht, etc.) of solvent molecules to the Gibbs energy of C₆₀ fullerene solution were calculated based on the additive group model. The effects of different functional groups on the solution process are discussed.     

Study on the Solute–Solvent Interactions Using the Solubility of Asymmetric Metal Complex, CoX2(R-py)2, as a Probe of Interaction

The solubility of some cobalt(II) chloride and bromide complexes of pyridine bases was determined in 10 inert organic solvents. The measured solubilities were analyzed using two different solvent parameters, i.e., Hildebrand's solubility parameter and Richard's E _T(30). These contributions to solubility are interpreted in terms of the asymmetric structure of the probe metal complex.     

Acid–base complexes of polymers

The physical interactions of polymers with neighboring molecules are determined by only two kinds of interactions: London dispersion forces and Lewis acid–base interactions. These two kinds of attractive energies (together with certain steric restrictions) determine solubility, solvent retention, plasticizer action, wettability, adsorption, adhesion, reinforcement, crystallinity, and mechanical properties. The London dispersion force interaction energies of polymers have been quantified by the dispersion force contribution to cohesive energy density (δ²_d) and the dispersion force contribution to surface energy (δ^d). The Lewis acid–base interactions, often referred to as “polar” interactions, can be best quantified by Drago's C_A and E_A constants for acid sites and C_B and E_B constants for basic sites. In this article infrared spectral shifts are featured as a method of determining enthalpies of acid–base interaction, and the C and E constants for polymers, plasticizers, and solvents. Examples are given where acid–base complexation of polymers with solvents dominate solubility and swelling phenomena. Enthalpies of acid–base complexation in polymer blends are determined from spectral shifts.     

Effect of nature of organic solvent on the absorption spectrum of C60 fullerene

Absorption spectrums of C₆₀ fullerene in 10 various organic solvents in the range of 300–620 nm was studied. In all the solvents the C₆₀ fullerene has four absorption maxima in the range under study. When an aromatic solvent has an ionization potential of 8.1 eV or lower a new additional absorption band appears in the absorption spectrum of C₆₀ fullerene, caused by the formation of a charge-transfer complex (CTC) of the solvent and C₆₀ fullerene.     

Thermodynamic properties of fullerene C60 solutions in a mixture of tetrachloromethane and toluene

The solubility of fullerene C₆₀ in the tetrachloromethane-toluene system is measured over the entire range of compositions of the mixed solvent in the temperature range 298.15–338.15 K. An equation is proposed for describing the solubility of C₆₀ as a function of the temperature and the composition of the mixed solvent. The equation is used for calculating the thermodynamic characteristics of solution of the fullerene. It is found that, in the investigated C₆₀-CCl₄/C₆H₅CH₃ system, two types of solid solvates of the fullerene with the solvent are formed. The enthalpies and temperatures of incongruent melting of the crystalline solvates are determined by differential scanning calorimetry. The thermodynamic characteristics of solution and solvation of C₆₀ in CCl₄ and C₆H₅CH₃ are obtained. It is shown that the entropy factor plays a decisive role in the temperature dependence of the Gibbs energy of solvation of the fullerene.     

Solubility characteristics of poly(3‐hexylthiophene)

Solubility data for poly(3‐hexylthiophene) (P3HT) in 29 pure solvents are presented and discussed in detail. Functional solubility parameter (FSP) and convex solubility parameter (CSP) computations are performed and the CSP and FSP results are compared to previously reported Hansen solubility parameters (HSPs) and to the parameters calculated using additive functional group contribution methods. The empirical data reveals experimental solubility parameters with substantial polar (δ_P) and hydrogen‐bonding (δ_H) components, which are not intrinsic to the structure of the P3HT polymer. Despite these apparent irregularities, it is shown that the predictor method based on the solubility function, f, does provide a reliable way to quantitatively evaluate the solubility of P3HT in other solvents in terms of a given set of empirical solubility data. The solubility behavior is further investigated using linear solvation energy relationship (LSER) modeling and COSMO‐RS computations of the activity coefficients of P3HT. The LSER model reveals that (1) the cavity term, δ_T, is the dominant factor governing the solubility behavior of P3HT and (2) the solvent characteristics that dictate the structural order (crystallinity) of P3HT aggregates do not similarly influence the overall solubility behavior of the polymer. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1075–1087     

反气相色谱法表征离子液体1-己基-3-甲基咪唑四氟硼酸盐的热力学参数

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-C₆、n-C₇、n-C₈、n-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.     

Unusual swelling behavior of films of polyvinyl- and polyvinylidene/fluorides in various solvents

The swelling of PVF and PVDF films in various solvents was investigated. It was found that in the swollen state both polymers show little tendency to retain the solvent that leaks out under a mild pressure and evaporates quickly when the specimen is exposed to air. The equilibrium swelling ratios were measured in numerous solvents. From the results it is concluded that the solubility parameters are δ_PVDF = 12.0–12.3, δ_PVF = 12.0–12.1. The unusual swelling behavior is explained by strong polymer–polymer interactions via dipoles which tend to replace polymer–solvent interactions once the sample is withdrawn from the solvent.     

Solvent effects in gel chromatography: the relationship between the distribution coefficients of metal acetylacetonates and solubility parameters of solvents

Distribution coefficients of metal acetylacetonates such as Al(acac)₃, Cr(acac)₃ and Co(acac)₃ etc., and n-alkanes in porous polystyrene gel chromatography with ten organic solvents as eluants were estimated and compared with those obtained by the batch method in two solvent systems. Solubility parameters of the metal acetylacetonates were determined. There is a relationship between the distribution coefficients and solubility parameters of solutes and solvents. Two factors (steric exclusion and partition) play important rôles in each solvent for the separation mechanisms of the present systems. The latter factor was estimated successfully from a regular solutions approximation.     

Solvent effects on the absorption spectra of merocyanine dyes

Solvent effects on the lowest-energy electronic transitions of two merocyanines derived from quinoline have been studied using nine different solvent parameters reported in the literature. Relative merits and deficiencies of different parameters have been assessed. From the correlation results, attempts have been made to propose a solute-solvent interaction mechanism. For an assorted set of 19 solvents, as well as for a set of nine hydroxylic solvents, excellent results are obtained with correlation equation involving E_T(30) and Hilderbrand's solubility parameter _H.     

Studies of the photoexcited states of the fullerenes, C60 and C70

The spectra of C₆₀ and C₇₀ were examined using low-temperature photoluminescence and quasi-elastic light scattering spectroscopy. A detailed vibronic analysis of the lowest triplet and singlet excited states of C₇₀ is obtained. The lowest triplet state is identified as a ³E₁′ state and the vibronic structure consists primarily of Herzberg-Teller active e₂′ modes. The intensity of the electronic origin is comparable to the vibronically induced intensity and is extraordinarily solvent sensitive. The spectrum of monosubstituted C₆₀ is shown to be qualitatively similar to that of C₆₀ in polar or strongly complexing solvents. The principal effect of solvent interaction or substitution is to induce dipole intensity in the orbitally forbidden electronic origins of the luminescent states of C₆₀ and C₇₀. The Rayleigh scattering of fullerene solutions illustrates that solute aggregation occurs easily and that aggregate nucleation is strongly affected by surfaces in contact with the solution.     

Solvent Effect on the Gibbs Energy of Proton Transfer in the 2,6-Dichlorophenol-Triethylamine Complex

Using dipole moment measurements, the Gibbs energy ΔG_PT of proton transfer in the complex of 2,6-dichlorophenol with triethylamine was determined in different solvents. The effect of solvent on ΔG_PT was quantitatively discussed in terms of reaction field models for homogeneous and heterogeneous dielectric media. The specific complex–solvent interactions which, in addition to electrostatic interaction, stabilize the PT polar form of the complex is discussed as a function of the empirical parameters describing the polar and hydrogen-donating (electron-accepting) properties of the solvent.     

Calculation of solubility of solid solutes in mixed non-aqueous solvents within the limits of the theory of molecular association

A method for calculating the solubility of solid substances in mixed non aqueous solvents is proposed based on the theory of molecular association and a simple lattice model (ASL = Associated Solution + Lattice). This method provides the calculation of the solubility of solids in mixed non aqueous solvents using only the molecular association parameters and the value of the interchange energy ω_AB that is derived from the phase equilibrium data in a mixed solvent.     

Catalytic polyaddition of benzene to fullerene and properties of the reaction product

The use of a catalyst based on aluminum trichloride and copper dichloride in the reaction of fullerene with benzene afforded C₆₀Ph₁₉H₁₉. At 400°C, this compound eliminates hydrogen to form C₆₀Ph₁₉. The compounds obtained are characterized by their high solubility in organic solvents, film-forming properties, and photoluminescence at 520 nm. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1219–1221, June, 1997.     

Studies on the Distribution of Phenoxyacetic Acid in Two-Phase Systems: n -Aliphatic Hydrocarbon – Water

Phenoxyacetic acid distribution in two-phase systems n-aliphatic hydrocarbon (C₅–C₈) – water and its dimerization in organic phase were investigated. The values of distribution coefficient (D _HR), distribution constant (K _D), and dimerization constant (K _dim) of acid were obtained. The empirical correlations of these quantities with Hildebrand solubility parameter of organic solvents were established. The influence of pH of the aqueous phase as well as the polarity of the applied organic solvents on phenoxyacetic acid physical chemistry in the two-phase systems was described.