Condensed Low-Volatile Alcohol Droplet-Directed Uniform Pore Formation on Polystyrene Films

摘要

In this work, various polystyrene (PS) films with uniform pores (0.18-1.26 m in size) are prepared through spin-casting polymer solutions consisting of PS, dichloromethane (CH2Cl2), and different low-volatile alcohols (propylene glycol, diglycol, triglycol, polyethylene glycol-200, -400, and -600). It is proposed that the formation of these uniform pores is directed by the condensed low-volatile alcohol droplets formed during the solvent evaporation; relevant evidences are provided. Five different indexes are defined to help reveal the mechanisms of the effects of PS content and alcohol property on the aggregation tendency of the alcohol molecules and on the growth of the alcohol droplets, and thus on the pore size.