No abstract

Graphene oxide (GO), modified with anti-aging agent p-phenylenediamine (PPD), was added into nitrile rubber (NBR) in order to improve the thermo-oxidative stability of NBR. The modification of GO and the transformation of functional groups were characterized by Fourier transform infrared spectroscopy (FTIR), Raman, and X-ray diffraction (XRD). Mechanical performances of NBR composites before and after the thermo-oxidative aging were recorded. The results of dynamic mechanical analysis (DMA) show an increased storage modulus (G’) and a decreased value of area of tan δ peak after introducing modified GO into NBR. It indicates that filler particles show positive interaction with molecular chains. The thermo-oxidative stability of composites was investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Then, the thermo-oxidative aging kinetic parameters were obtained by the Flynn–Wall–Ozawa (FWO) equation. The results of aging tests show that the thermo-oxidative stability of rubber matrix increases obviously after introducing GO–PPD. In addition, mechanical properties (tensile strength and elongation at break) of both before and after aged NBR/GO–PPD composites were superior to that of NBR. This work provides meaningful guidance for achieving multifunction thermo-oxidative aging resistance rubber composites.

Fe3O4 particles were surface coated with a layer of polyvinyl acetate (PVAc), which could improve their compatibility with EVA composite hot melt adhesives and then further induce EVA segments to orientate.

With the idea of improving the mechanical properties of acrylonitrile-butadiene rubber (NBR) for potential industrial application, hybrid nanofillers prepared by hybridizing graphene oxide (GO) with halloysite nanotubes (HNT), were incorporated through mechanical blending to reinforce NBR. Graphene oxide/halloysite nanotubes (GH) hybrid filler demonstrates significant synergetic reinforcement effect in mechanical properties of NBR. The substantial improvement in mechanical properties is attributed to the uniform dispersion of hybrid filler in the matrix and to the strong interaction between the hybrid filler and matrix. Scanning electron microscopy images obtained from the fractured surface of GH-reinforced NBR composites showed more uniform dispersion with less agglomerations and cracks than that of GO and HNT. The strong interaction between the hybrid filler and NBR was confirmed by the increase of glass transition temperature, storage modulus and crosslinking density.