CAVALCANTI, F. B.; http://lattes.cnpq.br/5762956202188573; CAVALCANTI, Felipe Barbosa.
Resumo:
The development of polymer blends from biodegradable polymers is a proposal
that has been growing in the search for products less harmful to the environment
after their disposal. The present work deals with the manufacture and
characterization of blends and composites using two synthetic biodegradable
polymers (Poly (butylene adipate co-terephthalate) - PBAT and Poly-ε-
caprolactone - PCL) and babassu mesocarp as a filler. The systems were
processed in internal mixer, granulated and extruded as flat films. Rheological,
mechanical, thermal, biodegradation and gas permeability properties of these
systems were determined and their fracture surfaces characterized by Optical
(MO) and Scanning Electron Microscopy (SEM). Based on the experimental data,
PBAT75/25PCL blends were chosen for the production of PBAT/PCL composites
with babassu contents of up to 5% by weight. Results indicate that degradation
of the blends during processing as well as their biodegradation increases with
PCL content and with the addition of the babassu fibers. They also show that
both, the incorporation of PCL and of babassu fibers, make the systems more
rigid, with variable effects in maximum stress. Analyzes by MEV and MO show
fiber aggregates and poor fiber / matrix adhesion as well as the presence of which
appears to be some micropores or bubbles in the composites. Thermal analysis
shows changes in crystallization and melting temperatures of the blends and the
composites and that the degree of crystallinity in the blends increases with PCL
content up to 25%, while that of the composites shows a reduction compared
with that of the reference blend. Gas permeability decreases with the
incorporation of babassu fiber. Babassu mesocarp incorporation led to decreased
permeability and increased biodegradation without significantly affecting the
mechanical properties of the PBAT/PCL (75/25) blend.