Effect of interfacial reaction and morphology on rheological properties of reactive bilayer

Abstract

We investigated the effect of interfacial reaction and morphology on the rheological properties of a reactive bilayer polymer system consisting of end-functionalized polystyrene with carboxylic acid (PS-mCOOH) and poly(methyl methacrylate-ran-glycidylmethacrylate) (PMMA-GMA). We found that the complex viscosity (\eta*\) of the reactive bilayer was unusually higher than the predicted value from the inverse relationship which holds for nonreactive bilayer, even though the interfacial roughness generated from PMMA-graft-PS copolymers formed in situ from the reaction near the interface was much smaller than the thicknesses of two plates of PS-mCOOH and PMMA-GMA. This indicates that in addition to the effect of the improved mechanical strength or interfacial mixing between chains by the presence of graft copolymers located near the interface, the roughness of the interface greatly influences \eta*\ of the reactive bilayer.