In this work, the use of homogenous media composed of the ionic liquid [C4MIM] [PF6) in combination with miscible compressed 1,1,1,2-tetrafluoroethane (R134a), above the critical points of the mixture, at 338.15 and 363.15 K and pressure of 30,000 kPa, lead to the successful enzyme-mediated syntheses of linear and hyperbranched poly-L-lactides. The attained polymer molecular weights were higher than those in previous reports using compressed fluids, even in the supercritical state, or individual ionic liquid media. The maximum attained M-n for linear PLLA in this work was 28,000 g/mol, and that for hyperbranched was 11,200 g/mol which were up to 3-fold higher than those obtained with the ionic liquid medium, and this is attributed to favored reaction media characteristics in this critical/miscible system. Additionally, non-enzymatic propagation side mechanisms were minimized or eliminated with the addition of the green compressed R134a. (C) 2015 Elsevier B.V. All rights reserved.