| Abstract: | Binder is the major factor of influencing rheological properties. This paper has systematically studied coating respectively contained oxidized starch, carboxylated styrene_butadiene latex and polyvinyl alcohol(PVA) with different addition. The results show that coatings all appear to be shear_thinning when shear rate is not high(<10 3/s), and they can be described by modified Power_Law Equation. The power index is a shear_rate function, which represents the dependence of fluid flow kind on shear rate. The experiment results also show that consistency coefficient K of the system with PVA binder is the largest, the one with oxidized starch is large, and the one with carboxylated SBR is the smallest. When binders are mixed with oxidized starch, carboxylated SBR, CMC and PVA to prepare coating, the systems are shear_thinning, and their apparent viscosity and shear rate relation can be expressed by a power function which the power index is a function of shear rate. Under the same conditions, the coating apparent viscosity with CMC is the largest, that with PVA is larger, and that with carboxylated SBR is small. |
