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10
Highly Toughened Polylactide-Based Materials through
Melt-Blending Techniques
Jérémy Odent, Jean-Marie Raquez, and Philippe Dubois

10.1
Introduction

10.1.1
Polylactide as a Bio-based Alternative

Driven by environmental awareness and fossil resources rarefaction, a lot of
attention has been paid to biopolymers as an “environmentally friendly” alter-
native to the current petroleum-based materials. Generally, biopolymers are
designed as biodegradable and/or bio-based; this includes biodegradable poly-
mers from renewable resources, biodegradable polymers from fossil resources,
nonbiodegradable polymers from renewable resources, and biodegradable
polymers industrially obtained from petroleum resources. Accordingly, a classifi-
cation of biopolymers over these four main categories has been proposed on the
basis of their origin and production method [1] (Figure 10.1). Only the first three
categories are obtained from renewable resources, which are natural polymers
from agro-resources (i.e., polysaccharides, starches), polymers obtained from
microbial production (i.e., polyhydroxyalkanoates), and polymers chemically
synthesized from bio-derived monomers (i.e., polylactides (PLAs)). Finally, we
can have the fourth classification of biodegradable polymers industrially obtained
from petroleum resources (i.e., polycaprolactone). Recently, it has been reported
that polycaprolactone can be potentially produced from renewable resources.
According to the standard specifications (ASTM D6400, ASTM D6868, ASTM
D7081, or EN 13432), biodegradability is defined as the capability of a material to
undergo decomposition into carbon dioxide, methane, water, inorganic compounds,
and biomass, in which the predominant mechanisms are the hydrolysis and the
enzymatic action of microorganisms [2]. Compostability and biodegradation are
the two main tests assessing the biodegradability of polymers as a function of
disposal conditions [3]. More precisely, compostability represents the biodegrad-
ability of a material buried in a compost medium where moisture, temperature,
and aerobic environment are controlled, while biodegradation is the degradation

Biodegradable Polyesters, First Edition. Edited by Stoyko Fakirov.
© 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2015 by Wiley-VCH Verlag GmbH & Co. KGaA.