Stability enhancement of polystyrene thin films by adding highly branched aromatic molecules, three-arm polystrene and metal oxide nanoparticles

Abstract

This study investigates the increasing of polymeric thin film stability via adding the highly branched aromatic molecules, three-arm polystyrene and metal oxide nanoparticles. The additive include novel synthesized highly branched aromatic molecules consisting of non-polar side chains and polar cores, three-arm polystyrenes with similar branch chain and surface energy to the polymer matrix, and two metal oxide nanoparticles i.e., titanium dioxide and zinc oxide. Polystyrenes with various molecular weight are used as polymer matrix in this study. The dewetting retardation phenomenon is followed by annealing the films in vacuum oven for different periods of time and examining the film morphology evolutions by using atomic force microscope and optical microscope. Then, dewetting area as a function of annealing time is calculated. It is found that the presence of the highly branched aromatic molecules, three-arm polystyrene and the inorganic nanoparticles considerably increase the stability of the polystyrene thin films. In addition, additive concentration, molecular weight of polymer matrix, and film thickness are found to affect stability of thin films. Mechanisms of dewetting suppression in the polymeric thin film containing these additives are also discussed in this research.