ELONGATIONAL FLOW BEHAVIOR OF ABS POLYMER MELTS

Elongational flow behavior of ABS polymer melts with various rubber-particle contents was investigated by using a Meissner-type uniaxial extensional rheometer. The effects of strain rate and rubber particles on the elongational behavior are discussed. A linear viscoelastic behavior was observed at sufficiently low strain rates e. The dependence of linear elongational viscosity tj£ (t)on particle content is weak at short times but becomes stronger with time. Two types of mechanisms which cause the deviation of nonlinear viscosity function 77 (tye) from Tj}: (/) at high strain rates in the short and long time regions were proposed. These deviations are respectively attributed to a volumetric resistance against the radial deformation of the samples because of the existence of particles, and an extension of matrix polymers in an elongational flow field. © 1990, The Society of Rheology. All rights reserved.