DENIS MIHAELA PANAITESCU, ANGELA CASARICA, PAUL OCTAVIAN STANESCU, MICHAELA DOINA IORGA, VIOLETA PURCAR, DOREL FLOREA, CONSTANTIN RADOVICI, ADRIANA NICOLETA FRONE* Comparative Analysis of Bacterial and Microcrystalline Celluloses as Reinforcements for Poly (3-hydroxybutyrate-co-3-hydroxyvalerate)

DENIS MIHAELA PANAITESCU, ANGELA CASARICA, PAUL OCTAVIAN STANESCU, MICHAELA DOINA IORGA, VIOLETA PURCAR, DOREL FLOREA, CONSTANTIN RADOVICI, ADRIANA NICOLETA FRONE* Comparative Analysis of Bacterial and Microcrystalline Celluloses as Reinforcements for Poly (3-hydroxybutyrate-co-3-hydroxyvalerate)

Abstract:
Cellulose and polyhydroxyalkanoates, polymers from renewable resources, have been intensively studied for the last decades and they are the main topic of this paper. Bacterial cellulose pellicles (BC) were synthesized in static culture fermentations and ultrasounds were used to disintegrate them into fibers (us-BC). Microcrystalline cellulose (MCC) and us-BC were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and infrared spectroscopy (ATR-FTIR) with a view toward their use in fully biodegradable and biocompatible polymer composites. Mechanical properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) modified with the two types of celluloses were also investigated. AFM images showed that big aggregates of BC fibers disappeared after ultrasound treatment but small aggregates coexist with separated fibers in us-BC sample. Higher XRD crystallinity and crystallite dimension were obtained for us-BC as compared to MCC. Mechanical tests on poly(3-hydroxybutyrate-co-3-hydroxyvalerate), neat and modified with the two cellulosic fillers, showed that the highest values of tensile strength and modulus were obtained in the case of the composite containing us-BC. Keywords: bacterial cellulose, polyhydroxyalkanoates, XRD, polymer composites, AFM

Issue: 2013 Volume 50, Issue 4

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