abstract
The preparation and characterization of biocomposite materials with improved properties based on poly(lactic acid) (PLA) and bacterial cellulose, and, for comparative purposes, vegetal cellulose fibers, both in their pristine form or after acetylation, is reported. The composite materials were obtained through the simple and green mechanical compounding of a PLA matrix and bacterial cellulose nanofibrils (or vegetable fibers), and were characterized by TGA, DSC, tensile assays, DMA, SEM and water uptake. The bionanocomposites obtained from PLA and acetylated bacterial cellulose were particularly interesting, given the considerable improvement in thermal and mechanical properties, as evidenced by the significant increase in both elastic and Young moduli, and in the tensile strength (increments of about 100, 40 and 25%, respectively) at very low nanofiller loadings (up to 6%). These nanocomposites also showed low hygroscopicity and considerable transparency, features reported here for the first time.
keywords
MICROFIBRILLATED CELLULOSE; THERMAL-PROPERTIES; POLYLACTIC ACID; COMPOSITES; FIBERS; NANOCOMPOSITES; SUBSTITUTION; BIOPOLYMER; MORPHOLOGY; WHISKERS
subject category
Chemistry; Science & Technology - Other Topics
authors
Tome, LC; Pinto, RJB; Trovatti, E; Freire, CSR; Silvestre, AJD; Neto, CP; Gandini, A
our authors
Alessandro Gandini
Researcher
Armando Jorge Domingues Silvestre
Full professor
Carlos Pascoal Neto
Raiz Director
Carmen Sofia da Rocha Freire Barros
Coordinating Researcher
Liliana C. Tomé
PhD Student
Ricardo Pinto
Researcheracknowledgements
FCT (Fundacao para a Ciencia e Tecnologia) is acknowledged for L. C. T. (Research grant PTDC/QUI/68472/2006) and for E. T. (Postdoctoral research grant SFRH/BPD/63250/2009), and for L. C. T. financial support under the scope of the Convenio FCT-CAPES 2009. The authors thank the FCT for funding within the scope of the