1973 年 22 巻 236 号 p. 421-423
Dynamic and steady-flow properties of disperse systems of styrene-divinylbenzene copolymer particles in polystyrene solution have been measured in wide ranges of frequency and shear rate by means of a cone-plate type rheometer.
The disperse systems show Newtonian flow at extremely low shear rates. This fact indicates that the systems have no yield stress, though they appear to have the yield stress when one gives attention only to the behavior at higher shear rates. At extremely low frequencies, the disperse systems show linear viscoelasticity regardless of the magnitude of strain amplitudes, and G' and G" are proportional, respectively, to ωω2 and ω. In this region, |η*| coincides well with Newtonian viscosity, but the empirical law proposed by Cox and Merz does not hold at higher frequencies and shear rates.