- abietic acid
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/ab"ee et"ik, ab'-/, Chem.a yellow, crystalline, water-insoluble acid, C20H30O2, obtained from the resin of a species of pine: used chiefly in driers, varnishes, and soaps. Also called sylvic acid.[1860-65; < L abiet- (s. of abies) fir + -IC]
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the most abundant of several closely related organic acids that constitute most of rosin, the solid portion of the oleoresin of coniferous trees. Commercial abietic acid is usually a glassy or partly crystalline, yellowish solid that melts at temperatures as low as 85° C (185° F). It belongs to the diterpene group of organic compounds (compounds derived from four isoprene units).Rosin has been used for centuries for caulking ships. It is also rubbed on the bows of musical instruments to make them less slippery. In modern times methods have been developed for improving the properties of the rosin acids, which are soft, tacky, and low-melting and subject to rapid deterioration by oxidation in air. Stability is greatly increased by heat treatment.Rosin acids are converted into ester gum by reaction with controlled amounts of glycerol or other polyhydric alcohols. Ester gum has drying properties and is used in paints, varnishes, and lacquers.* * *
Universalium. 2010.
