Miceliization and Surface Adsorption of Tetraethylammonium Perfluorooctanesulfonate in Mixed Solvents

The surface tension and cenductivity of tetracthylarnmomum perfluorooctanesulfonate (TEPFOS) solu-tions in mixed solvents were determined The criticsl micelle concentrations (cmc) and surface adsorption of TEPFOS in various solvents (Dimetbylsulfoxlde and DMSO, formamide and FA, and DMSO-H2O and FA H2O mixtures) were calculated from the above experimental date. The results show that the surface activity of TEPFOS is much higher than that of typical hydrocarbon surfactant, sodium dodecylsulfate (SDS); the melecalar interaction (in terms of colubility araneter or surface tension) of solvent is the decisive factor in sffecting the cmc of TEPFOS , in the apretic solvent DMSO, the value of entropy change during micelliza-tion of TEPFOS may beecme subsantially negative; the surfaof adsorption amount of TEPFOS is the largest in H2O, smaller in FA , and the smallest in DMSO.

Solubility of β-cyclodextrin in different mixed solvents

The solubility of β-cyclodextrin （β-CD） in ionic liquid/N, N-dimethyl-acetamide （IL/DMAC） mixed solvent and in LiCI/DMAC mixed solvent was investigated at 323.15 K and 353.15 K. The results showed that the solubility of β-CD in IL/DMAC system increased with increasing temperature, but decreased in LiCI/DMAC system. β-CD had the highest solubility in IL/DMAC system with [Cl]- or [Br]- anions. The solubility of β-CD in LiCl/DMAC system was lower than that in IL/DMAC system with [Cl]- or [Br]- anions but higher than that in IL/DMAC system with weak-coordinated anions （e.g [BF4]- or [PF6]-）. The effects of substituent groups （benzyl and butyl） of cation and the structure of cations on β-cyclodextrin solubility were also investigated.

CONTROLLING THE SURFACE COMPOSITION OF PCBM IN P3HT/PCBM BLEND FILMS BY USING MIXED SOLVENTS WITH DIFFERENT EVAPORATION RATES

The surface composition of poly（3-hexylthiophene-2,5-diyl） and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester （P3HT/PCBM） blend films could be changed by controlling the film formation process via using mixed solvents with different evaporation rates. The second solvent, with a higher boiling point than that of the first solvent and much better solubility for PCBM than P3HT, is chosen to mix with the first solvent with a lower boiling point and good solubility for both PCBM and P3HT. The slow evaporation rate of the second solvent provides enough time for PCBM to diffuse upwards during the solvent evaporation. Thus, the weight ratio of PCBM and P3HT （mpcBM/mp3HT） at surface of the blend films was varied from ca. 0.1 to ca. 0.72, i.e., it increases about seven times by changing from single solvent to mixed solvents. Meanwhile, the mixed solvents were in favor to form P3HT naonofiber network and enhance phase separation of P3HT/PCBM blend films. As a result, the power conversion efficiency of the device from mixed solvents with slow evaporation process was about 1.5 times of the one from single solvents.

Standard potential of the Ag-AgCl electrode and acidity constant of glycine at constant molality of NaCl in glucose-water mixed solvents from 278.15 to 318.15 K

Standard electrode potentials E° of Ag-AgC1 electrode in molality scale and acidity constants of glyeine pK_1° at constant molality of NaCl (1.0 mol·kg^(-1)) in 5 and 15 mass% glucose-water mixed solvents over a range of temperatures from 278.15 to 318.15 K were determined from precise emf measurements.The dependence of acidity constant on temperature is given as a function of the thermodynamic temperature T by an empirical equation, pK_1° =A_1(K/T)-A_2+A_3(T/K).The corresponding thermodynamic quantities of the first dissociation process of glycine were calculated and the effects of both tho solvent and the salt on them were also discussed.

Cation-π Interaction between the Aromatic Organic Counterion and DTAB Micelle in Mixed Solvents

The cation-p interaction between the aromatic organic counterion potassium hydrogen phthalate (KHP) and DTAB micelle in aqueous mixture of EG was investigated, using the techniques of conductivity measurements, UV absorption spectrum and NMR spectrum. The conductivity and UV spectrum studies were with respect to the effect of KHP on DTAB and that of DTAB micelle on KHP, respectively. According to the chemical shift changes of the aromatic ring and the surfactant methylene protons, it can be assumed that KHP penetrated into DTAB micelle with its carboxylic group protruding out of the micellar surface. And the strength of the interaction became weaker with the content of EG in the mixed solvent increasing.

Effect of Mixed Solvent on Fabrication, Morphology and Monodispersity of Microspheres with Hydrophobic Poly(butyl methacrylate) Shells

Monodisperse microspheres （mean diameter 200-300 nm） with polystyrene cores and poly（acrylamide-co-butyl methacrylate） shells were prepared by using a free radical polymerization method. Moreover, the effect of mixed solvent on the preparation, morphology and monodispersity was investigated. The experimental results showed that solubility parameter of butyl methacrylate and solvent affected mainly the molding of monodisperse core-shell microspheres. When the microspheres were fabricated in a sequential synthesis process, addition of hydrophilic and organic solvent including butyl methacrylate led to spherical degree of the particles becoming worse, and the mean diameter of the microspheres decreased and the monodispersity became better with increasing the crosslinker methylenebisacrylamide dosage.

Catalytic Synthesis of Methylene Diphenyl Dicarbamate in AcOH/H_2O Mixed Solvent

In a mixed solvent of acetic acid（AcOH）/water, methylene diphenyl dicarbamate（MDC） was synthesized by the condensation of methyl phenyl carbamate（MPC） and formaldehyde in the presence of an inorganic acid catalyst. Based on the different solubilities to MPC and MDC, the mixed solvent showed higher catalytic performance than pure water. The mixed solvent not only promoted the condensation of MPC but aslo exhibited the advantage of the product separation with the reactants. Under the optimized conditions： a H2SO4 mass fraction of 31%, a reaction temperature of 95 ℃ and reaction time of 3.5 h, the yield of MDC reached 74.3%. In addition, the recycle of the solvent was also investigated.

Thermodynamics of Ion Pair of Magnesium Sulfate in Mixed Solvent

Introduction Magnesium sulfate is an archetypal 2-2 salt that plays a central role in defining the characteristics of higher valent electrolyte solutions and its solution has been widely used to test various theories of strong electrolyte behavior and to develop models of ion association in solution. Up to now, the ion pairs of magnesium sulfate in an aqueous solution have been widely investigated by using different experimental techniques, such as conductometry , cryoscopy potentiometry solubility and Raman spectrometry. However, to our knowledge, no measurement of the standard association constant of the ion pairs, [ MgSO4 ]^0 in a glucosewater mixed solvent is available.

STUDY OF COMPOSITE MEMBRANE OF CELLULOSE ACETATE OR POLYVINYL ALCOHOL BLENDED WITH METHYLMETHACRYLATE-ACRYLIC ACID COPOLYMER FOR PERVAPORATION SEPARATION

In this paper, methylmethacrylate-acrylic acid MMA-AA hydrophilic and hydrophobic copolymers were prepared by copolymerization for preparing membrane materials. The composite membrane of cellulose acetate (CA) blended with MMA-AA hydrophobic copolymer was used for the separation of methanol from pentane-methanol mixture. When the methanol concentration was only 1 wt%, the permeate flux still maintained at 350 g/m(2)h and separation factor was as big as 800. The composite membrane of PVA (polyvinyl alcohol) blended with MMA-AA hydrophilic copolymer was used for the separation of ethanol-water mixture. The permeate flux was increased to 975 g/m(2)h at 74 degrees C and the separation factor reached 3000 at 25 degrees C. The PVA/MMA-AA blended membrane surface modified by ammonia plasma was also investigated for separating ethanol-water mixture. Both permeate flux and separation factor of the membrane was improved. However, there was no obvious difference of plasma treatment time in the interval of 20 similar to 40 min.

The effect of temperature on phase equilibria of polyethylene glycol(PEG8000)-K_(2)SO_(4)-H_(2)O at T=(288.15,298.15,308.15)K

The phase behavior of potassium sulfate(K_(2)SO_(4))in polyethylene glycol with molecular weight 8000(PEG8000)andwater(H_(2)O)mixed solvent at 288.15,298.15,and 308.15 Kwere determined.According to the results,when the temperature are 288.15 and 298.15 K,there is only a solid-liquid phase equilibrium relationship in the system,and the phase diagrams are both divided into three parts which respectively are the regions of unsaturated homogeneous liquid(L),one liquid and one solid K_(2)SO_(4)(L+S)and one liquid and twosolids K_(2)SO_(4) and PEG8000(L+2S).The solubility of K_(2)SO_(4) in PEG8000-H_(2)O mixed solvent decreased with the addition of the PEG8000 in the solution.Comparing the diagrams of 288.15 and 298.15 K,the sizes of regions of(L)and(L+S)increased and that of(L+2S)decreased with the increase of temperature.While at 308.15 K,solid-liquid and liquid-liquid equilibrium coexist,and there are six parts in the complete phase diagram at 308.15 K,adding the areas of one liquid and one solid K_(2)SO_(4)(L+S),two liquids(2 L),two liquids and one solid K_(2)SO_(4)(2 L+S).The equations developed by Merchuk,Hu,and Jayapalwere used to fit the binodal curves data of the systemat 308.15 K,meanwhile,the experimental tie-line data of the system at 308.15 K were correlated by Othmer-Tobias equation and Bancroft equation.

Influence of Molecular Interaction on Crystallization Behavior of Glycine from Mother Liquor

The mother liquor for preparing industrial HCN was investigated, to analyze the side-products’ structure and influence of molecular interactions of side-products with glycine and solvent on the glycine’s crystallization process. The side-products（SPs） were super-branched oligmers with plenty of hydrophilic groups, which could affect the crystallization process by interactions such as hydrogen bond. Alcohol-water mixed solvent with different polyols could be used to weaken the SPs-glycine interaction and strengthen the SPs-water interaction, which help to improve the crystallization efficiency and purity. After optimization, SPs’ mass fraction in glycine could be reduced by 80% and the morphology of crystal particles could also be improved.

Volum etric Properties of Sodium Chlorobenzoatein N,N-Dim ethylform am ide/waterMixtures at 298.15K

Densities of sodium chlorobenzoate( o , m , p ) were measured in solutions up to 80 weight percent dimethylformamide(DMF) at 298 15 K with an oscillating tube densimeter. From these densities, apparent molar volumes of sodium chlorobenzoate in DMF H 2O mixtures were calculated, and partial molar volumes at infinite dilution were evaluated. Substituent and solvent effects on transfer volumes of each isomer from water to DMF H 2O mixed solvents were obtained. The results are explained in terms of solvent structure and solute solvent interaction.

Prediction of Solid-Liquid Equilibrium for KCl in Mixed Water-Ethanol Solutions Using the LIQUAC Model

The LIQUAC model is often used to predict vapor-liquid equilibria, osmotic coefficients, and mean ion activity coefficients for electrolyte systems. This paper describes a thermodynamic method to analyze solid-liquid equilibrium for electrolytes in mixed solvents solutions using the LIQUAC model. The KCI solubilities in mixed water-ethanol solutions are predicted with the LIQUAC model and its original interaction parameters. This method is also used to obtain new K^＋-ethanol interaction parameters in the LIQUAC model from the solubility data. The new interaction parameters accurately predict the vapor-liquid equilibrium data of K^＋ salts （including KCI, KBr, and KCOOCH3） in mixed water-ethanol solutions. The results illustrate the flexibility of the LIQUAC model which can predict not only vapor-liquid equilibrium but also solid-liquid equilibrium in mixed solvent systems.

Influence of Mixed Common Solvent on the Co-assembled Morphology of PS-b-PEO and CdS Quantum Dots

The hybrid structures of polystyrene-b-poly（ethylene oxide） （PS-b-PEO） block copolymer and inorganic nanoparticles with good stability and biocompatibility have potential applications in drug delivery and bioimaging. Spherical co-assemblies of PS120-b-PEO318 and oleylamine-capped CdS quantum dots （QDs） are produced successfully in this work by adding water to a mixed common solvent, such as N,N-dimethylmethanamide （DMF）/chloroform, DMF/tetrahydrofuran （THF）, or DMF/toluene. The energy dispersive X-ray （EDX） spectrum indicates that QDs are located at the interface between the core and shell of the spherical co-assemblies. The co-assembly process during water addition is traced by transmission electron microscopy （TEM） and turbidity measurement. Spherical co-assemblies are formed through budding from bilayers of the block copolymer and QDs. The morphology of the co-assemblies is related to the miscibility of the QD-dispersing solvents with water and the morphology changes from a spherical to a vesicle-like structure with DMF/toluene. Increasing THF content in the mixed solvent causes morphological transitions from spherical co-assemblies to multi-branched cylinders and micelles where QDs are located in the central core. Increasing chloroform content yields vesicle-like structures with protruding rods on the surface. The mechanism of the morphological transitions is also discussed in detail.

The gelation rule of the polyol acetal derivatives in binary solvent mixtures

The gelation properties of polyol acetal derivatives including 2,4-（3,4-dichlorobenzylidene）-D-sorbitol（DCBS）, 1,3：2,4-di（3,4-dichlorobenzylidene）-D-sorbitol（DDCBS） and 1,3：2,5：4,6-tris（3,4-dichlorobenzylidene）-D-mannitol（TDCBM） in 35 single solvents and 39 binary solvent mixtures have been studied. FTIR and XRD results suggest that the self-assembly patterns of the gelator will not change in either the single solvent component or the corresponding solvent mixtures, but the critical gelation concentration（CGC）will be influenced. The results of SEM and rheology showed that the formation of true gels at saturated concentrations. Improving the heating temperature may promote the dissolving of gelators which are even insoluble at the temperature of the solvent boiling point and change the gelation behaviors. FloryHuggins parameter（x） was used to predict the gelation behavior of DCBS in the mixed solvents, and it is shown that the x values for the mixed solvents that can be gelled by DCBS are either greater or smaller than those for the selected good solvents.

The fabrication of hollow magnetite microspheres with a nearly 100% morphological yield and their applications in lithium ion batteries

Hollow Fe3O4（H-Fe3O4） microspheres were fabricated through a facile one-step solvothermal synthesis,which was performed in an ethylene glycol（EG）–diethylene glycol（DEG） mixed solvent using polyethylene glycol（PEG） as the stabilizer. The addition of DEG increased the viscosity of the system,which caused the Fe3O4 primary crystal to aggregate slower and the morphological yield to approach nearly 100%. The as-prepared hollow Fe3O4 microspheres show promise for application in lithium ion battery anodes and showed a reversible specific capacity of 453.3 mAh g^-1 after 50 cycles at 100 mA g^-1.

Analysis of Structure Transition and Compatibility of PTT/PC Blend without Transesterification

Poly（trimethylene terephthalate）/polycarbonate （PTT/PC） blends were prepared by solvent mixing to avoid transesterification during high temperature blending. The influences of compositions on the thermal behavior, crystallization morphology and structure of the blends were studied. FTIR results indicated that there was no CO0 linking to two phenyl groups on each side chain and DSC results supported no transesterification reaction. DSC curves showed that Tc and Tmc increased to maximum range when PC contents were between 7 wt%-15 wt%, however, Tm decreased constantly with the increase of PC contents. It was observed from POM that PTT spherulitic morphology and crystallization kinetics were obviously influenced by the change of PC contents. Structural evolutions during cooling were investigated by SAXS which showed Lc of PTT remained a constant with different PC contents and also fixed during crystallization, nevertheless, it revealed a maximum value of Lnc for sample PTT93. It was concluded that PC chains could be permeated into not only amorphous crystallite structure but also amorphous lamellae structure and 7 wt% PC content was supposed to be the ＂proper＂ penetration amount into PTT lamellae structure which led to a maximum capacity of amorphous lamellar layer. Fringedmicelle crystal model was adopted to illustrate semi-crystalline physical structures of the blend in two kinds of component aggregation states.