Poly(o-methoxyaniline) Modified by the Biphasic Ceramic System Na2Ti3O7/ Na2Ti6O13

We probed the structural modifications and electronic behavior of composites obtained from the admixture of a biphasic titanate ceramic system (Na2Ti3O7/Na2Ti6O13) with a poly(o-methoxyaniline, POMA) matrix. The composites were obtained by the addition of Na2Ti3O7/Na2Ti6O13to a POMA matrix in mass concentrations from 0 to 35%. The sodium titanates were synthesized by means of sonochemistry, while the polymer was obtained by conventional chemical polymerization. The structural analysis carried by XRD, FTIR and UV-Vis indicated mostly the presence of POMA, though the titanates could be identified in the composites with higher concentration. The XRD diffractograms showed narrow reflections that could be correlated to the Na2Ti6O13 phase and hydrogen titanates, whose presence indicates a process of partial substitution of H+ for Na+ ions. While the thermal degradation of the polymeric chains starts near 150 °C, the thermogravimetric and differential thermogravimetric (TG/dTG) analysis revealed that the presence of sodium titanates enhances the thermal stability of the composites. Finally, the addition of the biphasic ceramic to the composite increases the electrical resistivity drastically, from ≈ 102 Ω cm in the pure POMA to ≈ 104 Ω cm in the 35% composite.