AbstractFlow curves (shear stress versus shear rate) were obtained for poly‐(ethyl acrylate) containing up to 40 of gel particles over a range of shear rates from 3 × 10−3to 7 × 103sec.−1with a specially designed biconical rheometer and a standard Instron capillary viscometer. Crosslink density of the gels was varied by emulsion‐polymerizing ethyl acrylate with 3, 10, and 30 triethyleneglycol dimethacrylate. Particle sizes were varied by adjusting the concentration of emulsifying agent and by seeding techniques. Samples for study were prepared by blending and co‐precipitating the linear and gel latices. The addition of gel always increases the shear stress at a given shear rate. However, this effect is greatest at the lowest shear rates. The flow properties of the gelcontaining materials are related quantitatively to those of the linear material through a new parameter, the rate of viscous energy dissipation, and by two material constants. These are a yield stress and a pseudo zero‐shear viscosity, both of these being functions of the amount, crosslink density, and particle size of
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