D-lactic acid structure and physicochemical properties

The scientific name of lactic acid α-hydroxy acid, formula C2H5OCOOH, is a naturally occurring calcium lactate, is widely present in the human body, animals, plants and microbes.
Lactic acid is the smallest natural chiral molecules carboxyl group in α-carbon atom is an asymmetric carbon atom, with L (+) and D (-)-isomers. L-lactic acid is D-type, D-lactic acid is L-type, L-lactic acid and D-lactic acid is the ratio of the racemic mixture of DL-type. D-lactic acid and L-lactic acid in addition to the optically active, the other physical properties are the same as [2], but the physical properties of DL-type vary with them, and in its melting point and heat of fusion than a single D-or L-configuration of low.
D-lactic acid with a magnessium lactate typical chemical properties of a weak acid solution, the concentration of more than 50% portion is formed when milk anhydride, the reaction of alcohols with some alkyd resin, the heating conditions can be intermolecular esterification , to form lactic acid lactylate (C6H10O5), heating may be further diluted and hydrolyzed to D-lactic acid. Role of zinc oxide in the dehydrating agent, the removal of two molecules of two
molecules of D-lactic acid in water, to form a cyclic dimer from poly D-lactide (C6H8O4, DLA). Sufficiently dehydrated D-lactic acid polymer can be formed. The more concentrated the acid esterification stronger the trend itself, thus lactic acid and lactic acid is typically a mixture of lactide.