(810d) The Structure and Rheology of Carbon Nanotubes Adsorbed At An Air-Water Interface

Ma, A., University of Connecticut
Vora, S., University of Connecticut
Guo, Y., University of Connecticut
Patanwala, H., University of Connecticut

Particles of appropriate size and wetability adsorb strongly at gas-liquid and liquid-liquid interfaces and lower the interfacial energy. The ability of particles to stabilize foams and emulsions was well documented by Ramsden and Pickering more than a century ago. The effect of particle shape has, however, remained largely unexplored and unexploited. We hypothesize that the particle shape matters and that rod-like particles will increase the number of particle-particle contacts, leading to the formation of a stronger layer at the interface relative to spheres. To examine this hypothesize, we have chosen carbon nanotubes (CNTs) as a model system given their high aspect ratio (>1000). In this presentation, we will report our recent findings on the microstructure and interfacial rheology of a CNT-decorated interface. The latter is directly related to the mechanical integrity and stability of the interface. Our findings indicate that CNTs adsorb strongly at the air-water interface, leading to a significant increase in surface pressure. The highly compressible nature of an interface also enables the creation of two-dimensional CNT “liquid crystals” by compressing a CNT-decorated interface.