LA and GA are usually synthesized by ring-opening polymerization of cyclic monomers.
The block copolymers can be synthesized using various kinds of different catalysts, but also in the absence of catalysts. One of the most widely used catalysts is stannous octoate.
Synthesis of PLGA-PEG block copolymers using stannous octoate. The terminal hydroxyl groups of PEG have been used as the initiating groups to synthesize block copolymers