Branching of interfacial cracks of carbon nanotube layers at the air-water interface⋆.

We study the surfactant-induced fracture of carbon nanotube layers at the air-water interface. The interfacial cracks exhibit branched morphologies. The propagation velocity V of the cracks follows a power law as [Formula: see text] , which is independent of the surface coverage of the layers as well as the surfactant concentration. However, the crack morphology changes from lightning-like to flower-like with the increasing of SDS concentration. A higher surfactant concentration does not accelerate the crack propagation velocity, whereas it significantly enhances the crack areas due to the stronger interfacial compression effect. Our results may shed light on the understanding of branching dynamics of interfacial cracks for 2-dimensional viscoelastic systems.