(15) There are three steps to typically synthesize lactide: (i) removal of free water from aqueous lactic acid to form concentrated lactic acid; (ii) formation of lactic acid oligomers (<5000 g/mol) at temperatures of 120 °C to 140 °C and pressure 3 kPa; and (iii) an intramolecular esterification process (called “ ...

How do you make lactide?

Lactide is prepared by a two-step process: first, the lactic acid is converted into oligo(lactic acid) by a polycondensation reaction; second, the oligo(lactic acid) is thermally depolymerized to form the cyclic lactide via an unzipping mechanism.

How do you synthesize polylactic acid?

Now, the synthesis of PLA polymers can be performed by direct polycondensation of lactic acid as well as by ring-opening polymerization of lactide (LA), a cyclic dimer of lactic acid.