Syntheses and chemical transformations of glycolide and lactide as monomers for biodegradable polymers

Glycolide and lactide function as the commonly used diester monomers for the preparation of high-molecular weight, degradation-prone (co-)polyesters. Both glycolide and lactide-based polymers are widely used in medicine, pharmaceuticals, the food industry, and additive technologies. This review on the diesters, spanning research from 1833-1854 to the present, encompassing their structural peculiarities, physico-chemical properties, and the range of different methods for obtaining them – including reaction mechanisms – from lactic and glycolic acids, their esters, and halogen derivatives. The review also discusses the chemical transformations of lactide and glycolide (apart from ring-opening polymerization) into valuable organic and high-molecular compounds, such as acrylic acid, nitrogen-containing heterocycles, and functional polymers with novel properties.