A Green Route for the Preparation of Aliphatic Polyesters via Lipase-catalyzed Prepolymerization and Low-temperature Postpolymerization Stamatina N. Vouyiouka,* Evangelos Topakas, Adamantia Katsini, Constantine D. Papaspyrides, Paul Christakopoulos 1. Introduction The utilization of fossil fuels in the manufacture of plastics accounts for about 7% of worldwide oil and gas. Never- theless, it seems clear that although biodegradability can help reduce plastic waste, from a ‘‘green house’’ perspective, biobased sustainable materials, the so-called bioplastics, are currently considered the way to go and may be the only alternative in the future as fossil resources become exhausted. Aliphatic polyesters derived from hydroxy acids, e.g., poly(lactic acid) (PLA), as well as from diacids and diols, e.g., poly(butylene succinate) (PBS), comprise the most promising biodegradable materials. PLA, already commercially available (e.g., NatureWorks), is produced from renewable resources such as corn or sugar beets, it presents mechanical strength, transparency, compostabil- ity, and biocompatibility, while its high glass transition point, low crystallization rate, and ductility comprise its Full Paper S. N. Vouyiouka, A. Katsini, C. D. Papaspyrides Laboratory of Polymer Technology, School of Chemical Engineering, National Technical University of Athens, Zographou, Athens 15780, Greece E-mail: mvuyiuka@central.ntua.gr E. Topakas, P. Christakopoulos Laboratory of Biotechnology, BIOtechMASS Unit, School of Chemical Engineering, National Technical University of Athens, Zographou, Athens 15780, Greece Lipase-catalyzed polycondensation of two biobased diacids, 1,12-dodecanedioic acid and 1,14-tetradecanedioic acid, with 1,8-octanediol was achieved using immobilized Lipase B from Candida antarctica. The procedure resulted in partially renewable prepolymers, while poly(octylene adipate) from petroleum- based adipic acid was also synthesized for comparison reasons, revealing a dependence of the enzymatic polymeri- zation degree on monomer composition. The prepolymers were further sub- mitted to bulk postpolymerization at temperatures in the vicinity of their melting point under flowing nitrogen. The intrinsic viscosity increase was found up to 12%, with no significant impact on the polyesters thermal prop- erties. ß 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim wileyonlinelibrary.com Macromol. Mater. Eng. 2012, DOI: 10.1002/mame.201200188 1 Early View Publication; these are NOT the final page numbers, use DOI for citation !! R