Rosin acids, determination

Acid-Insoluble Ash, 748 Acidity Determination by Iodometric Method (Flavor Chemicals), 565 Acid-Modified Starch, 159 Acid Number (Rosins and Related Substances), 832... 

Rosin is a complex mixture, mainly consisting of various isomers of rosin acid. When exposed to air for a long period, rosins are easily discolored by oxidation. High-pressure DSC (HPDSC) can be used to determine oxidative stability of various rosins and rosin products. The measurement method is as follows ... 

A number of factors must be considered in blending elastomer latexes and resin dispersions. A formulator must determine that the emulsifier systems are compatible. Many resin dispersions are prepared with anionic emulsifiers based on rosin acids. The pH of these... 

Most fatty acids are obtained by hydrolysis of oils from various oleochemical sources (animal, marine and plant) and the composition of fatty acids in the oil is determined by its origin and production method. An exception to this is the widely used tall oil fatty acid products, obtained as free fatty acids together with rosin acid from paper pulping. Animal sources, for example lard and tallow, are characterized by high concentrations of saturated fatty acids, while marine sources (fish oils) are characterized by long-chain and unsaturated acids. The fatty acid composition of oils from plant sources varies greatly... 

Studies on the differentiation between alkyd enamels by conventional Py-GC have been carried out. As discussed previously, more structural information about alkyd enamels may be obtained by the THM technique. Polybasic acid, polyhydric alcohol, drying oil composition, oil length, degree of cure, and any rosin modification can be determined. The discrimination between alkyd enamels is therefore improved. For example, the alkyd enamel whose pyrogram is shown in Figure 8.4 gives the THM profile shown in Figure 8.5. 

For the determination of certain amino acids some other enzymes may be applied. For instance, Kumar and Christian [226] used tyrosinase (polyphenol oxidase, E.C.1.14.18.1) for the determination of L-ty-rosine in serum. 

Lodi S, Rosin G (1995) Determination of some organic acids in sugar factory products. J Chromatogr A 706 375-383... 

Spalik conducted a study to determine whether flux or the oxidation of Pb° in the solder caused the decrease in tin concentration observed with flip chip solder joints (C4) that experienced multiple reflows. Differential scanning calorimetry analyses made on 90Pb l0Sn solder samples both before and after heating to about 350°C in the presence of a rosin flux for more than 24 hr showed no detectable change in the tin content. This result was consistent with the requirement that in order for a metal to dissolve in an acid, H2 must be evolved. In other words, the following reaction must occur ... 

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