Solvents Kauri-Butanol value

AROMATIC HYDROCARBON SOLVENTS Kauri Butanol Value cc. Aniltne F POHU AlMOtule Viscosity CpS A 26 C Flash Point TagCC. F Explotive Umtis %byVot.lnAlr Composition % By Volume Solu- Param- elers... 

The first attempts at predicting solubility were largely empirical. Paint technologists employed various approaches. In one approach kauri-butanol values were equal to the minimum volume of test solvent that produced turbidity when added to a standard solution of kauri-copal resin in 1-butanol. The aniline point is the lowest temperature where equal volumes of aniline and the test solvent are completely miscible. Both tests are measures of the relative aromaticity of the test solvent. 

Prior to the introduction of the solubility parameter (solpar) concept, paint chemists used Kauri butanol values, mixed aniline points, and heptane numbers to predict the solubility of resins in aliphatic solvents. These parameters have been replaced, to a large extent, by solpars, but heptane numbers are still used, and these empirical parameters can be converted to solpar values. 

KAURI-BUTANOL VALUE. A measure of the aromatic content and hence the solvent power of a hydrocarbon liquid Kauri gum is readily soluble in butanol but insoluble in hydrocarbons. The kb value is Ihe measure of the volume of solvent required to produce turbidity in a standard solution containing kauri gum dissolved in butanol. Naphtha fractions have a kb value of about 30. and toluene about 105. 

In particular, methyl soyate (the biodiesel formed from soybean oil and methanol) is finding industrial applications including cleaning and degreasing technologies (Table 5.5). In industry, solvents are needed to dissolve a material for its removal or transport and then are often evaporated to restore the original material. Therefore, two important parameters are solvent power and evaporation rate. One way to measure solvent power is the kauri-butanol value (KBV), which is a measure of the solubility of kauri gum in the solvent. A high... 

Tetrafluoroethane is a hydrofluorocarbon (HFC) or hydro-fluoroalkane (HFA) aerosol propellant (contains hydrogen, fluorine, and carbon) as contrasted to a CFC (chlorine, fluorine, and carbon). The lack of chlorine in the molecule and the presence of hydrogen reduces the ozone depletion activity to practically zero. Hence tetrafluoroethane can be considered as an alternative to CFCs in the formulation of metered-dose inhalers (MDIs). It has replaced CFC-12 as a refrigerant since it has essentially the same vapor pressure. Its very low Kauri-butanol value and solubility parameter indicate that it is not a good solvent for the commonly used surfactants for MDIs. Sorbitan trioleate, sorbitan sesquioleate, oleic acid, and soya lecithin show limited solubility in tetrafluoroethane and the amount of surfactant that actually dissolves may not be sufficient to keep a drug readily dispersed. 

The major incompatibility of tetrafluoroethane is its lack of miscibility with water. Since it has a very low Kauri-butanol value, tetrafluoroethane is considered to be a very poor solvent for most drugs used in MDI formulations. It also shows a low solubility for some of the commonly used MDI surfactants. 

A particularly common test for ranking hydrocarbon solvent strength is the kauri-butanol test. The kauri-butanol value (KB) of a solvent represents the maximum amount of the solvent that can be added to a stock solution of kauri resin (a fossil copal) in butyl alcohol without causing cloudiness. Because kauri resin is readily soluble in butyl alcohol but not in hydrocarbon solvents, the resin solution will tolerate only a certain amount of dilution. Stronger solvents such as toluene can be added in a greater amount (and thus have a higher KB value) than weaker solvents like hexane. 

The kauri-butanol value (ASTM D-1133) is the number of milliliters of the solvent, at 15°C (TT F), required to produce a defined degree of turbidity when added to 20 g of a standard solution of gum kauri resin in n-butyl alcohol. The kauri-butanol value of naphtha is used to determine relative solvent power. 

Solvent properties Solubility parameter Kauri butanol value ... 

Table 4.5 Kauri-Butanol values for several cleaning solvents ...

Kauri-Butanol values for some solvents and cleaners are listed and compared in Table 4.5. Values for other cleaners may be found in Table 4.2. 

Standard test method for Kauri-Butanol value of hydrocarbon solvents, ASTM D1133-02, Book of Standards, Vol. 6.04. 

CHLORINATED SOLVENTS Vapor Press. a 20 C mm Hg Evaporation Rate Kauri Butanol Value ce. Freeze Point c ... 

Simpler methods are also used. In the paint industry, Kauri butanol values are determined by establishing the tolerance of a standard solution of Kauri resin in n-butanol to the addition of diluents. This method is applicable to hydrocarbons (both aromatic and aliphatic) and CFCs. Figure 2.3.20 shows that there is a good correlation between the Kauri butanol number and the Hildebrand solubility parameter. The Kauri butanol number can be as high as 1000 (amyl ester of lactic acid) or 500 (Freon solvent M-162). 

Solvent strength Solvent strength is used to establish required solvent concentration to form a clear solution and to estimate the diluting capabilities of pre-designed system. T wo determined quantities are used for the purpose Kauri butanol value and aniline point. 

Kauri-butanol value, KB is used for evaluation of dissolving ability of hydrocarbon solvents. It is obtained by titration of a standard Kauri resin solution (20 wt% in 1 -butanol) with the solvent until a cloud point is reached (for example, when it becomes impossible to read a text through the solution). The amount of the solvent used for titration is taken as KB value. The relationship between KB and solubility parameter, 5, fits the following empirical dependence ... 

Table 4.5. Kauri-Butanol Values for Several Cleaning Solvents...

Kauri-butanol value Volume in ml at 25°C (77°F) of a solvent, corrected to a defined standard, required to produce a defined degree of turbidity when added to 20 g of a standard solution of kauri resin in normal butyl alcohol. For kauri-butanol values of 69 and above, the standard is toluene and has an assigned value of 105. For kauri-butanol values below 60, the standard is a blend of 75% n-heptane and 25% toluene and has an assigned value of 40. Abbreviation is KB value. Paint pigment, drying oils, polymers, resins, naval stores, cellulosics esters, and ink vehicles, vol 3. American Society for Testing and Material, Conshohocken, PA, 2001. Fhck EW (1991) Industrial synthetic resins handbook. Williams Andrews Publishing/Noyes, New York. 

See kauri-butanol value, aniline point, and solubility parameter. Also called solvent power. 

Standard Test Method for Kauri-Butanol Value of Hydrocarbon Solvents,... 

The Kauri-butanol value, used to rate solvency of hydrocarbon solvents, is defined in ASTM Method D 1133 as the volume in milliliters of the hydrocarbon solvent at 25 °C that is required to produce a defined degree of turbidity when titrated into a specified quantity of a standard clear solution of kauri resin in n-butyl alcohol. Kauri-butanol values range from approximately 20 for the weakest hydrocarbon solvents to more than 100 for stronger aromatic solvents. The test is limited to hydrocarbon solvents and is not applicable to oxygenated solvents. As Kauri resin (a natural resin) is no longer easily available, the test has not maintained its acceptance in the industry. Aniline point (or mixed aniline point), another measure of solvency of hydrocarbon solvents, is more accepted. The ani-... 

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