Linear viscoelastic behavior of compatibilized PMMA/PP blends

In this work, the morphology and linear viscoelastic behavior of PMMA/PP blends to which a graft copolymer PP-g-PMMA has been added was studied. The copolymer concentration varied from 1 to 10 wt % relative to the dispersed phase concentration. The rheological data were used to infer the interfacial tension between the blended components. It was observed that PP-g-PMMA was effective as a compatibilizer for PMMA/PP blends. For PP-g-PMMA concentration added below the critical concentration of interface saturation, two rheological behaviors were observed depending on the blend concentration: for 70/30 blend, the storage modulus, at low frequencies, increased as compared to the one of the unmodified blend; for 90/10 blend, it decreased. For 90/10 blend, the relaxation spectrum presented an interfacial relaxation time related to the presence of the compatibilizer (). For PP-g-PMMA concentrations added above the critical concentration of interface saturation, the storage modulus of all blends increased as compared with the one of the unmodified blend. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013