Measurement of melt rheology under Biaxial and planar elongations and rheological properties of ethylene-Methacrylic ionomer melts

Abstract

To obtain reproducible, reliable data, the effects of experimental conditions on biaxial and planar elongational viscosities were investigated. It was clarified that a constant area method was preferable rather than a constant volume method. It was concluded that the effects of the viscosity of silicone oil as lubricant were negligible when the constant area method was employed. On the other hand, the effects of ion aggregates on zero shear viscosities η0 for ethylene-co-methacrylic ionomer melts were investigated. Rapid increasing of η0 for Zn ionomers was observed at high neutralization degrees, however, the rapid increase was not observed at all range of the degree neutralization in the case of Na ionomers. The formation of ion aggregates affects on damping functions in both cases of Na and Zn ionomers. This degree of neutralization well corresponds to the onset of strong strain dependence of h(γ) and increasing η0 for EMAA-Zn. © 2009 The Society of Rheology, Japan.