Microbial Bio-polyesters: Crystallinity and Mechanical Properties
Pp. 436-490 (55)
Maria Cristina Righetti, Andrea Lazzeri and Patrizia Cinelli
Crystalline structure and morphology of the solid state of thermoplastic
semi-crystalline polymers strongly affect their properties and performances. This is
particularly evident on mechanical properties of poly[(R)-3-hydroxybutyrate] (PHB),
and its copolymers, blends, composites, and nanocomposites. The organization and the
morphology of the crystals and the interconnection between the crystalline and the
amorphous regions can influence and govern the mechanical properties of PHB based
The presence of a rigid amorphous fraction, which produces a stiffening of the
amorphous segments at the crystal/amorphous interface, can contribute to the
progressive change of the mechanical properties in PHB based materials.
Properties of PHB based materials may be tuned and controlled by blending with other
polymers, by addition of properly selected plasticizers, nucleating agents, as well as by
addition of fillers and nanofillers.
In the present Chapter the influence of the morphology and the crystalline content on
the mechanical properties of PHB based materials is analyzed and discussed.
Blends, Composites, Crystallinity, Mechanical properties, Mobile amorphous
fraction, Morphology, Polyhydroxyalkanoates (PHA), Poly[(R)-3-hydroxybutyrate]
(PHB), Polymer processing, Polymers, Rigid amorphous fraction.
Department of Civil and Industrial Engineering, Largo Lucio Lazzarino 1, 56112, Pisa, Italy.