Epoxidized natural rubber/acid functionalized carbon nanotubes composites for enhanced thermo-mechanical and oxygen barrier performance

Herein, acid functionalized carbon nanotubes (FCNTs) reinforced epoxidized natural rubber (ENR 25) composites with 25% epoxidation are studied with particular reference to the effect of FCNTs on microstructural development along with their effect on thermo-mechanical and gas barrier properties. Excellent improvement in tensile strength, that is, 128% and 118%, was observed with the addition 1 and 2 wt% of FCNTs, respectively, without compromising the elongation at break. A 76% improvement in oxygen impermeability was found for 2 wt% of FCNTs. Chemical interactions among FCNTs and ENR 25 altered the composite morphology and led to good dispersion, both of which contribute to the excellent thermo-mechanical and gas barrier properties of the composites. The distribution of the filler inside ENR 25 has been characterized with scanning electron microscopy, which unveiled segregated FCNTs. The obtained experimental gas permeability values were correlated with the well-known Bharadwaj model. The fabricated functional composites could find applications in automobiles, packaging, and other demanding engineering sectors.