Viscosity of organic liquids

Pachaiyappan, V., Ibrahim, S.H., Kuloor, N.R. Simple Correlation for Determining Viscosity of Organic Liquids, Chemical Engineering, May 22, 1967, p. 193. 

Measurements of the viscosity of organic liquids in the presence of an electric field reveal that there is an increase in viscosity in high electric fields that is described by the expression... 

Skubla, P., Prediction of Viscosity of Organic Liquids. Collect. Czech. Chem. Commun., 1985 50, 1907-1916. 

Chatteijee A, Vasant AK (1982) Estimation of viscosity of organic liquids. Chem Ind 11 375-376... 

CORRELATIONS FOR DETERMINING NORMAL BOILING POINT AND KINEMATIC VISCOSITY OF ORGANIC LIQUIDS. 

The viscosity of organic liquids depends on both temperature and pressure molecular motion becomes more difficult as free volume is reduced, and the viscosity increases. To a first approximation, the viscosity of polymer melts can be written ... 

Medani, M. 1 Hasan, M. A. (1977). Viscosity of organic liquids at elevated temperatures and the corresponding vapour pressures. Can. J. Chem. Eng., 55, 203-209. 

There are numerous applications where the development of high viscosity is necessary in a finished product. For example, thickeners, mainly based on poly(acrylic acid), are used to give body to so-called emulsion paints. Emulsion paints are not formulated from true emulsions (Le. stable dispersions of organic liquids in water), but are prepared from latexes, that is, dispersions of polymer in water. Since latexes do not contain soluble polymers, they have a viscosity almost the same as pure water. As such, they would not sustain a pigment dispersion, but would allow it to settle they would also fail to flow out adequately when painted on to a surface. Inclusion of a thickener in the formulation gives a paint in which the pigment does not settle out and which can readily be applied by brush to a surface. 

Hydrogen-bond formation is of importance also for various other properties of substances, such as the solubility of organic liquids in water and other solvents, melting points of substances under water,1 viscosity of liquids,14 second virial coefficient of gases,18 choice of crystal structure, cleavage and hardness of crystals, infrared absorption spectra, and proton magnetic resonance. Some of these are discussed in the following sections of this chapter. 

Pressurized solvent extraction (PSE), also called pressurized fluid extraction (PEE), accelerated solvent extraction (ASE ), pressurized liquid extraction (PEE), or enhanced solvent extraction (ESE), is a solid-liquid extraction that has been developed as an alternative to conventional extractions such as Soxhlet, maceration, percolation, or reflux. It uses organic solvents at high pressure and temperature to increase the efficiency of the extraction process. Increased temperature decreases the viscosity of the liquid solvent, enhances its diffusivity, and accelerates the extraction kinetics. High pressure keeps the solvent in its liquid state and thus facilitates its penetration into the matrix, resulting in increase extraction speed [30]. 

Estimation of Liquid Viscosity of Organic Compounds with a Quantitative Structure-Property Model. 

Ivanciuc, O., Ivanciuc, T, Filip, P.A. and Cabrol-Bass, D. (1999b). Estimation of the Liquid Viscosity of Organic Compounds with a Quantitative Structure-Property Model. J.Chem.Inf.Comput.Sci., 39,515-524. 

Suzuki, T., Ohtaguchi, K. and Koide, K. (1996). Computer-Assisted Approach to Develop a New Prediction Method of Liquid Viscosity of Organic Compounds. Computers Chem.Eng., 20, 161-173. 

Estimation of liquid mixture viscosity without any mixture data is difficult because the viscosity is strongly affected by large molecular size differences and strong cross interactions between the different types of molecules. Viscosity-composition plots for aqueous mixtures can have maxima or minima, and viscosities for these mixtures are particularly difficult to estimate. The UNIFAC-VISCO method described below can be used to predict liquid viscosity of organic mixtures without any mixture data. It is relatively successful even for large differences in molecular size, but it is currently limited in scope by the small number of group contributions available. 

Orrick C, Erbar EJH (1973) Estimation of viscosity for organic liquids. Proposition Report, Oklahoma State University, Stillwater... 

Such a derivation was originally developed and used by Kirchoff [1858] and Rankine [1849] ( ) to express the temperature dependence of vapor pressure. It was also successfully used by Brostow (O to express the temperature dependence of the isothermal compressibility of a wide variety of organic liquids, some metallic liquids and water. By a similar analogy, we have used it to express the viscosity of liquid mold fluxes. 

To sum up, enzymes in ionic liquids could maintain their activity over a much longer period than in molecular organic solvents. This stabilization has been explained on the basis of the interaction of the ionic liquid ions as well as higher viscosity of ionic liquids with respect to conventional organic solvent, which could cause slower migration of protein domains from the active conformation into the inactive one. [33]. 

The choice of suitable surfactants and additional chemicals for the decontamination of source zones largely depends on the type of pollutant and the structure of the soil (mainly on adsorption behaviour and hydraulic conductivity). Adsorbed and solid pollutants or very viscous liquid phases cannot be mobilised. Preformed microemulsions, co-solvents or co-surfactants can be favourably used for such contaminations in order to enhance the solubilisation capacity of surfactants. NAPL with low viscosity can easily be mobilised and also effectively solubilised by microemulsion-forming surfactant systems. Mobilisation is usually much more efficient. It is achieved by reducing the interfacial tension between NAPL and water. Droplets of organic liquids, which are trapped in the pore bodies, can more easily be transported through the pore necks at lower interfacial tension (see Fig. 10.2). The onset of mobilisation is determined by the trapping number, which is dependent on... 

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