FABRICATION AND CHARACTERIZATION OF ELECTROSPUN POLYLACTIC ACID FILMS REINFORCED WITH CHILEAN BAMBOO CELLULOSE NANOFIBERS

Films with uniform fibers composed of polylactic acid (PLA) reinforced with cellulose nanofibers (CNF), with loadings of 1%, 3% and 5%, have been fabricated by electrospinning. The CNF were obtained from Kraft pulp of Chusquea quila, by mechanical high shear treatment in a microfluidizer. For the reinforcement treatment, the CNF were acetylated before preparing the PLA electrospun solution. The obtained CNF were observed using atomic force microscopy (AFM) and analyzed after acetylation using FT-IR spectroscopy to confirm their modification. Morphology studies on the films were conducted using scanning electron microscopy (SEM). The films were tested via tearing tests according to ASTM D1938 (2014). Besides, the films were subjected to photodegradation experiments according to ASTM D4329 (2013) and to mechanical testing to analyze the influence of photodegradation on their mechanical properties. The addition of 1% CNF was translated into an important increase in tear strength, which in some cases reached a 37% increase. After the photodegradation test, the films lost up to 46% of their original tensile strength.