(186b) Multifunctional Elastomer Nanocomposites With Functionalized Graphene Single Sheets

We present the effects of incorporation of completely exfoliated graphene nanoplatelets on the physical properties of rubber nanocomposites. The functionalized graphene sheets (FGS) with very high aspects ratios (100-10000) and specific surface areas (1800 m2/g) are obtained through rapid thermal expansion of graphite oxide. Both thermoset and thermoplastic elastomer-FGS nanocomposites offer better or equal mechanical, electrical and gas barrier properties compared to nanotube, clay and carbon black (CB) filled systems. For example, the tensile tests show that both modulus and strength increases by ~ 400 % in styrene-butadiene rubber (SBR) with 2 wt % FGS loading. WAXS measurements coupled with tensile tests reveal that the incorporation of FGS into natural rubber (NR) significantly shifts the onset of strain-induced crystallization to lower elongations compared to neat and CB filled matrix. The rheological and electrical percolation is achieved at low volume fractions (<1 vol % ) of FGS in various systems due to its high aspect ratio. The gas barrier properties of FGS filled elastomers are studied and the results are compared to the available models. The effects of processing methods (melt vs. solution), surface area of FGS and degree of surface functionality on the filler dispersion and physical properties will be discussed.