Poly(4,4'-oxydiphenylene-oxydiphthalimide) (POO) was thermally treated at 773 K for 1, 15 and 60 minutes under argon atmosphere resulting in free-standing films with intermingled characteristics between polymer and carbon-rich derivatives. Degradative thermal analysis performed by pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS) revealed CO 2 among the major products of thermal decomposition which according to electron paramagnetic resonance (EPR) passed through a radical process. X-ray diffraction (XRD) revealed thermal treated samples with semicrystalline organization that was attributed to the development of lamellae structure. Moreover, Atomic force microscopy (AFM) showed an increase in the roughness of the samples that acquired pronounced roughcast-like surface. Hence, there was an enhancement of mechanical strength and dielectric permittivity. From the data collected a mechanism of thermal decomposition was proposed.

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The dielectric, pyroelectric and ferroelectric properties of bilayered BaTiO3/BaTi0.8Zr0.2O3 ceramics are described and correlated with their microstructure. Different sintering times are employed to change the microstructure and promote interdiffusion between the layers. The effects of constrained sintering on both compositions are analyzed and their properties are compared to that of single phase BaTiO3 and BaTi0.8Zr0.2O3 ceramics. The results show that, at sintering times until 2 hours, the bilayer properties are predominantly affected by the presence of residual stresses. Only after 4 hours sintering, the properties are predominantly affected by interdiffusion between the layers.