1,4-Dioxane-2,5-dione, 3,6-dimethyl-, (3S,6S)-, polymer with oxirane, monomethyl ether, diblock Ethylene glycol-L-lactide diblock copolymer Ethylene oxide-L-lactide diblock copolymer monomethyl ether L-Lactide-ethylene oxide diblock copolymer methyl ether L-Lactide-oxirane diblock copolymer methyl ether L-Lactide-oxirane diblock copolymer monomethyl ether L-Lactide-polyethylene glycol monomethyl ether copolymer