Bacterial cellulose films with controlled microstructure–mechanical property relationships

Abstract

Bacterial cellulose (BC) films with different porosities have been developed in order to obtain improved mechanical properties. After 13 days of incubation of Gluconobacter xylinum bacteria in static culture, BC pellicles have been set. BC films have been compression molded after water dispersion of BC pellicles and filtration by applying different pressures (10, 50, and 100 MPa) to obtain films with different porosities. Tensile behavior has been analyzed in order to discuss the microstructureproperty relationships. Compression pressure has been found as an important parameter to control the final mechanical properties of BC films where slightly enhanced tensile strength and deformation at break are obtained increasing mold compression pressure, while modulus also increases following a nearly linear dependence upon film porosity. This behavior is related to the higher densification by increasing mold compression pressure that reduces the interfibrillar space, thus increasing the possibility of interfibrillar bonding zones. Network theories have been applied to relate film elastic properties with individual nanofiber properties.

Nanostructured composite materials reinforced with nature-based cellulose nanofibres

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Bacterial Cellulose for Skin Repair Materials

“…Compression pressure has been found to be an important parameter controlling the final mechanical properties of BC films: Slightly enhanced tensile strength and deformation at break were obtained by increasing the molding compression pressure, while the modulus also decreased nearly linearly with increasing film porosity. This behavior was related to higher densification under the increased mold compression pressure which reduced the interfibrillar space, thus increasing the probability of interfibrillar bonding (Retegi et al, 2010).…”

Assessing stiffness of nanofibres in bacterial cellulose hydrogels: Numerical-experimental framework

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