Wednesday, 28 June 2006 - 11:30 AM Federal Room B (Capital Hilton) 118
Carbon nanotube composites from soy-based resins
Ian M. McAninch and Richard P. Wool. University of Delaware, Newark, DE
Carbon nanotubes (CNTs) with their impressive mechanical properties are ideal reinforcement material. Acrylated epoxidized soy oil (AESO), a bio-based resin, has been previously shown to have favorable interactions with carbon nanotubes. CNTs mixed into AESO, both with and without styrene as a co-monomer, using mechanical shear mixing resulted in composites with modest mechanical property improvements. By itself, methyl methacrylate (MMA) appears to be a better dispersing agent for CNTs than styrene, so MMA was used as an alternative co-monomer. CNTs were dispersed via sonication in MMA, which was then mixed with AESO. CNTs were also mechanically mixed with a MMA/AESO resin. The resulting composites showed little dependence on the mixing method. Overall, the greatest improvements in mechanical properties, as measured by dynamic mechanical analysis, were seen when the resin's viscosity was kept high, either by having no co-monomer or by curing at a lower temperature. All samples showed increased properties in the rubbery modulus, with increases ranging from 20-70%. The dispersion of CNTs in the composites was investigated using SEM and optical microscopy. Some micron-sized aggregates were seen in all samples though the fewest were seen in the AESO-only composites, the ones with the highest bio-based content. The most were seen in the AESO/styrene composites.