Grafting of poly(epsilon-caprolactone) (PCL) and poly(lactide) (PLA) chains on poly(vinyl alcohol) backbone (PVA degree of hydrolysis 99%) was investigated using MgH2 environmental catalyst and melt-grown ring-opening polymerization (ROP) of epsilon-caprolactone (CL) and L-lactide (LA), that avoiding undesirable toxic catalyst and solvent. The ability of MgH2 as catalyst as well as yield of reaction were discussed according to various PVA/CL/MgH2 and PVA/LA/MgH2 ratio. PVA-g-PCL and PVA-g-PLA were characterized by H-1- and C-13-NMR, DSC, SEC, IR. For graft copolymers easily soluble in tetrahydrofuran (THF) or chloroform, wettability and surface energy of cast film varied in relation with the length and number of hydrophobic chains. Aqueous solution of micelle-like particles was realized by dissolution in THF then addition of water. Critical micelle concentration (CMC) decreased with hydrophobic chains. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 1188-1197, 2009