Rim instability by solvent-induced dewetting.

We study the condition of the occurrence of the rim instability in the solvent-induced dewetting process. Our experimental results show that the film thickness not only greatly influences the occurrence of the rim instability, but also influences the wavelength λ as characterized by the undulation of the deformed contact line. The molecular weight of polymer does not almost influence the occurrence of the rim instability and the wavelength λ. The wavelength λ is proportional to the width of the rim in the rim instability region. The receding contact angle θ of polymer solutions on substrates in the dewetting process is an important factor to influence the rim instability in the solvent-induced dewetting. [ABSTRACT FROM AUTHOR]