SILVA, T. R. G.; http://lattes.cnpq.br/6717107569018110; SILVA, Taciana Regina de Gouveia.
Resumen:
The polymers derived from petroleum have caused environmental impacts due
to improper disposal. An alternative to this problem is the use of biodegradable
polymers or blends production from these polymers. In this work, blends of poly
(lactic acid) - PLA, poly (-caprolactone) - PCL, were prepared with three
different copolymers: EMA, E-GMA and EMA-GMA are copolymers the
ethylene-methyl acrylate, ethylene-glycidyl methacrylate and terpolymer
ethylene-methyl acrylate-glycidyl methacrylate respectively. The compositions
used in the blends were as follows: PLA/PCL (90/10) PLA/PCL (80/20) PLA/
Copolymer (90/10) and PLA/PCL/Copolymer (80/10/10). These were prepared
by melting in an extruder twin screw co-rotating and then injection molded in the
form of specimens tensile, impact and HDT. All compositions were
characterized by: mechanical tensile and impact , heat distortion temperature -
HDT, differential scanning calorimetry - DSC, X-ray diffraction - XRD, dynamic
mechanical thermal analysis – DMTA, spectroscopy in the infrared region by
transform Fourier - FTIR, scanning electron microscopy - SEM, torque
rheometer, rheological testing and capillary rheometer. The mechanical
properties showed reduced values of modulus and tensile strength and an
increase in elongation and impact resistance for all compositions when
compared with pure PLA, especially for compositions containing copolymer
EMA-GMA. The HDT showed no significant changes for the different
compositions compared with pure PLA. The thermal and thermomechanical
behavior was evaluated by DSC and DMTA and it was possible to observe the
thermal transition of the blends. XRD was possible to observe the crystalline
phases of the blends of PLA. The morphology of the fracture surface was
observed by SEM illustrated that significant changes as a function of
composition. The torque rheometer results showed no significant change in the
behavior of PLA, while the rheological test results illustrate the increase in
storage modulus in all compositions. From the test capillary rheometer was seen that there was a reduction in the apparent viscosity and shear stress at
high shear rates for all compositions.