CESARIO, L. V.; http://lattes.cnpq.br/4708265017487456; CESARIO, Luanna Vilela.
Résumé:
Biodegradable plastics are a new class of polymers which have been extensively
explored in order to minimize environmental problems and meet industrial
requirements. One of the most promising biodegradable polymers for use in
packaging is poly (butylene adipate-co-terephthalate) (PBAT) which, however, needs
to be previously aged of photo-oxidized in order to loose mass at fast rates when
composted. In the present study cobalt and magnesium stearates were added to a
biodegradable PBAT matrix in order to evaluate the effect of these additives on the
mechanical and thermal properties, gas permeability and degradation of films made
with these systems. PBAT / stearate systems were processed in an internal mixer,
ground up and extruded as flat films. The tensile, thermal and morphological
properties of the films before the degradation tests (biodegradation and hydrolytic
degradation) were evaluated. The results show that the incorporation of the additives
to the PBAT initiates degradation of the polymer matrix during processing, and
accelerates crystallization. The mechanical properties of the films decreased with the
addition of the stearates in the polymer matrix. Finally, degradation studies
(biodegradation and hydrolytic degradation) confirm that cobalt stearate was more
effective in accelerating degradation of PBAT than magnesium stearate.