We report the bulk polymerization of ethylglycolide (3,6-diethyl-1,4-dioxane-2,5-dione), isobutylglycolide (3,6-diisobutyl-1,4-dioxane-2,5-dione), and hexylglycolide (3,6-dihexyl-1,4-dioxane-2,5-dione) to high molecular weight polymers. The glycolides were prepared by two routes: the reaction of 2-bromoacyl bromides and alpha-hydroxy acids and the acid-catalyzed oligomerization of 2-hydroxy acids followed by thermal depolymerization of the oligomers in the presence of ZnO. Both methods gave the substituted glycolides as a mixture of diastereomers. The monomers were melt-polymerized using Sn(2-ethylhexanoate)(2), SnO, SnBr2, SnBr4, PbO, and Ph4Sn with alcohol initiators. The polymerization rates depend on the steric bulk of the monomer, and the kinetic data for polymerizations using Sn(2-ethylhexanoate)(2) can be fit to an equilibrium model. High molecular weight poly(ethylglycolide), poly(isobutylglycolide), and poly(hexylglycolide) have T-g＇s of 12, 22, and -37 degrees C, respectively. These polymers are amorphous and decompose to monomer above 300 degrees C.