Molecular visualization of conformation-triggered flow instability

A new type of flow fingering instability was obsd. in monolayer-thick acrylic graft polymer films as they spread on a solid substrate. Tracing the movement of individual mols. by at. force microscopy enabled us to follow the development of the flow instability on the mol. level and to understand the underlying phys. mechanism. The fingering instability was obsd. to be triggered by conformational changes of brushlike macromols. in response to the pressure gradient driving the flow. [on SciFinder(R)]