Energy dissipation behaviors of a dispersed viscoelastic microsphere system

Abstract

Abstract Dispersed viscoelastic microsphere systems have preliminarily been applied in oil fields with gratifying successes. In this paper, a type of viscoelastic microsphere system with an average particle size of 100.6 μm was synthesized by employing the inverse suspension polymerization. The synthesized viscoelastic microspheres could swell 25.42 times due to the three-dimension structure. The rheological properties of dispersed viscoelastic microsphere system were researched by dynamic strain amplitude scanning measurements and the energy dissipation behaviors were investigated through mathematical method. The results showed that the dispersed system exhibited “shear-thickening” behavior when the strain was greater than the critical strain at different fixed angular frequency. The area enclosed by LISSAJOUS curves or normalized LISSAJOUS curves increased with the increasing of the strain at fixed angular frequency. The relationship between the dissipated energy ( E d ) and strain amplitude ( γ max ) is: E d = K ( γ max ) α . And the relationship between the dissipated energy exponent ( α ) and the fixed angular frequency( ω ) is: α ∝ ω 0.131±0.009 . Therefore, as the strain increases, the clusters grow up gradually and block the flow of the system, which results in “shear-thickening” and the demand of additional energy.