masterThesis
Obtenção e caracterização físico-química de blendas poliméricas, baseadas em POE e PMMA, dopadas com dióxido de titânio
Fecha
2013-05-28Registro en:
LIMA, Elias Januário de. Obtenção e caracterização físico-química de blendas
poliméricas, baseadas em POE e PMMA, dopadas com dióxido
de titânio. 2013. 107 f. Dissertação (Mestrado em Físico-Química; Química) - Universidade Federal do Rio Grande do Norte, Natal, 2013.
Autor
Lima, Elias Januário de
Resumen
The study of polymer blends has been an alternative method in the search field of new
materials for obtaining materials with improved properties. In this work blends of
poly(methyl methacrylate) (PMMA) and poly(ethylene oxide) (PEO) doped with titanium
dioxide (TiO2) were studied. The PEO is a polymer semicrystalline structure varying between,
70 and 84% crystallinity, while the PMMA exhibits behavior amorphous in their structure.
The use of TiO2 is related to corrosion-resistant of titanium as well as good heat transfer and
other characteristics. The study of these polymer blends doped TiO2 gives the properties
junction organic (polymer) and inorganic (oxide) which leads to modification of the
properties of the resultant material. The blends were doped TiO2 (POE/PMMA/TiO2) in
different proportions of the PMMA with the PEO and TiO2 fixed. The ratios were: 90/10/0,1;
85/15/0, 1; 80/20/0,1, 75/25/0,1 and 70/30/0,1. The resulting material was obtained in powder
form and being characterized by Fourier Transformed Infrared (FTIR) Spectroscopy,
Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Thermogravimetric
Analysis (TGA) and Electrochemical Impedance Spectroscopy (EIS). The infrared spectra
(IR) for the blends in different ratios showed a band at 1744 cm-1, characteristic of the C=O
stretching, which increases in intensity with increasing PMMA composition, while in the
spectrum of pure PEO this band is absent. This may suggest that the interaction is occurring
between the polymers. In the micrographs of the blends also observed change in their surfaces
with variation of the composition of PMMA, contributing to the change of the electrical
properties of the material. The EIS data showed that the material exhibited conductivity of the
order of 10-6 S.cm-1. The blend in the ratio B2(85/15/0, 1) showed better conductivity, σ =
1.56 x 10-6 S.cm-1. It was observed that the diffusion coefficient for the blends, B5(70/30/0, 1)
was the largest, 1.07 x 10-6 m2.s-1. The XRD data showing that, with the variation in the
composition of the PMMA blend crystallinity of the material is decreased reaching a
minimum B3(80/20/0,1), and then increases again. Thermal analysis suggests that blends
made from the material obtained can be applied at room temperature