The role of interface in gas barrier properties of styrene butadiene rubber-reduced graphene oxide composites

Abstract

The important role of interfacial effects, compared to the tortuosity effect, in permeation of nitrogen gas through styrene butadiene rubber-reduced graphene oxide (rGO) composites is presented by varying in-situ reduction of GO particles in SBR latex. Particles were initially synthesized, chemically reduced, and characterized as guidelines for the in-situ reduction in the latex compounding method. The latex mixing method provided a mean to minimize the difference in the state of dispersion and intercalation of particles in the samples, as revealed by field-emission scanning electron microscope and X-ray diffraction. However, in-situ chemical reduction of GO in the latex offered a simple method to manipulate the filler-rubber interfacial behavior in the composites, as revealed by the differential scanning calorimeter and bound rubber. Gas barrier performance of the samples showed that interfacial effects are as important as tortuosity effects and need to be considered seriously in rubber composites. Shortcomings of analytical models, exclusively based on the tortuous path, was discussed. A significant improvement of 92% in the permeability of nitrogen by 4 phr loading of rGO60 (reduced at 60 °C) was achieved.