When Liquids are Liquids or Maybe Not: Nano Seminar Series

Seminar | December 6 | 2-3 p.m. | 120 Latimer Hall

 Prof. Thomas P. Russell, Univ of Massachusetts / Polymer Science and Engineering

 Berkeley Nanosciences and Nanoengineering Institute

We introduce systems of liquids trapped in non-equilibrium configurations by interfacial assemblies of nanoparticle surfactants (‘NPSs’). These constructs consist of aqueous threads, length ~10-100 cm and diameter ~100 m whose mechanical properties are determined by an interfacial NPS assembly 20 nm thick. The interfacial layer consists of nanoparticles and polymers with complementary functionality, that interact only at the oil-water interface, to generate NPS that are irreversibly bound to the oil-water interface.

The shapes can be extensively deformed and reconfigured while maintaining macroscopic structural integrity, and are stable against coalescence. The films are self-healing, so that any ruptures in the film may rapidly be repaired. Furthermore, the system is compatible with a wealth of different nanoparticles, including metallic nanocrystals, meaning the interface can be readily functionalized.

The liquids retain their fluid characteristics: reagents can be flowed through them continuously, and they can be trivially rendered responsive to external stimuli.

Potential applications as a biphasic reaction medium and as responsive, self-regulating systems whose internal environment can be readily altered will be considered.
Tom Russell is the Conte Distinguished Prof at the Univ of Mass/Amherst and Assoc Editor of Macromolecules. He has held numerous influential roles including the boards of APS, MRS, SSRL, Advanced Materials, AAAS, and been awarded many polymer physics research and teaching honors.