The fluid type was determined by fitting the rheological profiles to Powerlaw model. The effect of temperature on the rheological behavior was investigated according to the viscous flowactivation energy(Eη) which was calculated by the Arrhenius formula.
RESULTS:
The viscosity of carrageenansolution decreased with the increase of shear rate and temperature, whereas it increased with the concentration. There existed a positive correlation between Eη and concentration. Furthermore, the effects of different cations on the viscosity were also studied and the results indicated that the viscosity increased significantly with the ionic concentration, especially that of potassium chloride.
CONCLUSION:
Carrageenan was inferred to be pseudo-plastic fluid which hasthe character of shear thinning effect and its viscosity is significantly affected by cationic species.