Influence of modified graphite flakes on the physical, thermo-mechanical and barrier properties of butyl rubber

Abstract The effects of expanded graphite (EG)/carbon black (CB) hybrid nanofillers on the physical, mechanical, thermo-mechanical, electrical and barrier properties of butyl rubber (IIR) vulcanizates have been widely investigated in the present study. Chemical treatment followed by a thermal exfoliation of natural graphite flakes have been done to synthesize EG. EG was further modified by treating it with mixed acid that resulted in an increase in the number of polar groups on its surface which indeed improves interfacial adhesion between the EG and rubber matrix as well as facilitates the curing reaction. The presence of different functional groups on the surface of modified EG (MEG) is confirmed by fourier transforms infrared spectroscopic (FT-IR) analysis. Significant increase in the d-spacing of MEG was observed from the wide angle X-ray diffraction analysis. The morphology of the IIR based hybrid nanocomposites have been investigated by high resolution transmission electron microscopy (HR-TEM). EG and MEG loaded IIR based nanocomposites with and without CB show an increase in the mechanical, thermo-mechanical, electrical, thermal and barrier properties compared to the neat polymer.