Structural evolution and enhanced thermal stability of composites based on isotactic polypropylene and nitrile-butadiene rubber reinforced with CoO nanoparticles

Nanocomposites based on isotactic polypropylene (PP), nitrile- butadiene rubber (NBR), and a nanofiller containing cobalt oxide nanoparticles stabilized by a low-density polyethylene matrix were obtained by mixing in a melt. The structural and morphological features of the obtained materials were studied using X-ray diffraction and atomic force microscopy (AFM). The thermo-physical properties were evaluated by thermogravimetric analysis, and the mechanical characteristics were evaluated by measuring the tensile strength and elongation at break. It was found that the introduction of a nanofiller at a concentration of 1.0 wt% of the PP/NBR matrix leads to a significant increase in operational performance. The tensile strength increased from 13.76 to 21.69 MPa, and the elongation at break increased from 22% to 40%. The improvement in thermal stability is explained by the formation of a small-spherulite layered structure and increased interphase interactions. According to the AFM data, cobalt oxide nanoparticles act as artificial nucleation centers, acting as effective structural modifiers of the polymer matrix. The results obtained demonstrate the possibility of directional regulation of the supramolecular architecture of composites to create high-strength, thermostable materials with improved morphological characteristics.