Study on rheological properties of CMC/Eu-Tb solutions with different concentrations

2018 5th Global Conference on Polymer and Composite Materials

材料科学;化学

Fu, Z.C.^1 ; Ye, J.^1 ; Xiong, J.^2

State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou

510640, China^1

School of Food Science and Engineering, South China University of Technology, Guangzhou

510640, China^2

关键词: Carboxymethyl cellulose;    Increasing temperatures;    Low concentrations;    Rheological property;    Shear-thinning behavior;    Solution concentration;    Steady-state flows;    Viscoelastic response;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/369/1/012039/pdf
DOI  :  10.1088/1757-899X/369/1/012039

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

The rheological properties of polymer solution are sensitive to variations in the polymer structure. Carboxymethyl cellulose (CMC) aqueous solution has been used in many fields, such as food, medicine and paper industry. In this paper, the effects of different concentrations (2% - 6%) of CMC/Eu-Tb on their rheological properties were investigeted, including steady-state flow and viscoelastic response. The results show that, the viscosity of CMC/Eu-Tb is lower than that of CMC, at the same concentrations; the products solutions present a nearly Newtonian behavior at the low concentrations (2% - 3%); while at the higher concentrations (4% - 6%), the products solutions present a pseudoplastic behavior; shear-thinning behavior is due to the polymer chains unravel under the action of flow and the molecular chains are oriented in the flow direction. The results also show that the viscosity of the solutions decreases with increasing temperature. Dynamic rheological tests show that CMC/Eu-Tb has viscoelasticity in the concentrations of 2% - 6%. At lower concentrations, the elastic modulus G′ is slightly higher than the viscous modulus G″, and as the concentrations increase, the elastic modulus G′ is significantly higher than the viscous modulus G″. It means that at the lower solution concentrations, the solutions tend to be less elastic and easier to flow. Most of the energies are lost through the viscous flow. As the solution concentrations increase, the solutions tend to be more elastic, and the system tends to form a gel.