The ABC of pattern evolution in self-destruction of thin polymer films

Abstract

We present the first real time observation of the pattern evolution in self-destruction of thin polymer films based on experiments with polydimethylsiloxane films sandwiched between silicon wafers and aqueous surfactant solutions. Four distinct stages of pattern evolution have been identified: (A)amplification of surface fluctuations, (B)breakup of the film and formation of holes, (C)growth and coalescence of holes and, (D)droplet formation and ripening. Only one of these stages, A, is unique to self-destruction of thin films as stages B, C and D are also present in nucleation induced dewetting of the film. As similar looking undulating patterns characterize stages A and C, it becomes imperative to have a full temporal evolution of the pattern to identify different stages and the likely mechanism of film breakup.