Interplay of polymer matrix and nanosized redox dopant with regard to thermo-oxidative and pyrolytic stability: CeO2 nanoparticles in a milieu of aromatic polyimides

Publication date: March 2020Source: Materials Today Communications, Volume 22Author(s): Alexandra L. Nikolaeva, Iosif V. Gofman, Alexander V. Yakimansky, Elena M. Ivan’kova, Natalia S. Gulii, Maria A. Teplonogova, Olga S. Ivanova, Alexander E. Baranchikov, Vladimir K. IvanovAbstractA series of polyimide/CeO2 nanocomposite films were fabricated based on three polymer matrices. The prepared films were characterized by scanning electron microscopy (SEM), thermomechanical analysis (TMA), and also simultaneous thermogravimetric (TGA) and differential thermal analysis (DTA), the latter two having been performed both in air and in inert (argon) atmosphere. Ceria nanoparticles were shown to be well dispersed in the PI matrix. TGA analysis revealed that the effect of ceria nanoparticles on thermal and thermo-oxidative stability of the nanocomposites depends strongly on the chemical nature of the polyimide. Thus, thermal properties of a nanocomposite based on the polyimide containing SO2-groups in the elementary unit of the polymer chain were found to be substantially enhanced upon incorporation of the nanoparticles in the matrix. In contrast, the polyimide with no sulfonic groups had a decreased thermo-oxidative stability being doped with CeO2 nanoparticles. The possible mechanism of polymer matrix – ceria nanoparticles interactions determining the nanocomposite thermal stability change is discussed.
Source: Materials Today Communications - Category: Materials Science Source Type: research

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