(411d) Mechanical Strength of Janus Colloidal Monolayers

Identifying the key factors that impact the structural and dynamical properties of colloidal monolayers is central to designing particle-laden interfaces with a desired stability. Although the wettability of the particle surface can be tuned to control the inter-particle interactions and flow behavior of a particle-laden interface, homogeneous colloidal particles with a uniform surface wettability are not amphiphilic in nature. Amphiphilic Janus particles are believed to partition strongly to interfaces and form a pliable interfacial skin.  Moreover, the dual nature of a Janus particle can serves as a platform to achieve further functionalities in addition to interface stabilization. Despite the great potential that lies in the interfacial confinement of Janus particles, little information is available on how the introduction of the particle surface anisotropy influences the response of a particle-laden interface to compression and the ensuing collapse mechanism. We have studied the interfacial configuration of Janus particles with intermediate and high degree of amphiphilicity at the air/water interface. Additionally, we have investigated the resulting mechanical strength of the monolayers. Our findings suggest that the type and strength of the interactions between different faces of Janus particles are critical in determining the mechanical properties of the interfacial layer.