Miscibility enhancement of polystyrene and poly(alkylene oxide) blends using specific intermolecular interactions
Acid–base interactions were used to enhance the miscibility of blends of polystyrene and oligomeric poly(alkylene oxide). The polystyrene was modified by sulfonation of less than 5% of the styrene rings. The poly(alkylene oxides) were low molar mass polyethylene oxide chains (M = 900 and 6000) that were end capped with propyl amine groups. Blends of the poly(alkylene oxide) diamines with polystyrene were immiscible. Blends with the sulfonated polystyrenes were miscible due to proton transfer from the sulfonic acid groups to the basic amino groups of the functionalized poly(alkylene oxide). This was confirmed by FTIR. DSC and dynamic mechanical analyses were used to verify the one- or two-phase nature of the blends.