Poly(lactic acid) is a well known polymer for more than 20 years in the biomedical fields applications. Today, according to rising prices of oil and massive consumption of fossil resource, this biodegradable aliphatic polyester is on the way to be a wide used commodity polymer. Moreover PLA is as a "green plastic" because it is synthesized from annually renewable resources. In many ways similar to poly(ethylene terephtalate) such as rigidity, transparency, crystallization kinetics and food

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... ct ability, it fulfills the packaging industry requirements for most of the rigid objects. But for applications like hot food packages, soft films and stretch blow bottles for example some properties of PLA have to be improved like heat deflection temperature (HDT), impact stiffness and gas barrier properties. There are many ways reported in literature today to improve these properties. In order to compare it with other well known polymers, figure 1 represents thermal properties of PLA and these polymers. The aim of the work deals to identify actual weaknesses of commercial grades of PLA. Secondly, to present pertinent ways to improve PLA"s properties have been identified according to chosen process and final properties wished. This study is composed of three main items. In a first time, a bibliographical study is necessary to identify the different ways to improve PLA"s properties used by researchers and industrials in literature. The most significant ways will be describe here. Then PLA compound (PLA with additives or PLA copolymers for examples) will be synthesized in conditions closed to industrial conditions studying crystallisation kinetic and rheological properties. In this step thermal, physico-chemical and mechanical properties of products synthesized will be characterized. At the end of this study the best ways of improving PLA"s behavior will be presented and described