流变仪介绍资料 rev.b 2015 - 网页版-english
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Shenzhen Sunlord Electronics Co., Ltd.
Rev.B 2015 Service Contact: Tel：0755-29832333(ext.2665), E-mail: [email protected]
Rheometer The instrument applies to analysising viscosity, pseudoplastic, expansibility, thixotropy, and viscoelasticity and yield point for solution, slurry, cream-body and paste samples. It is widely used in various fields, such as petrochemical engineering, high polymer material, electronic material, food, pharmacy, cosmetic, detergent, coating and chemicals and so on.
Shenzhen Sunlord Electronics Co., Ltd.
Rev.B 2015 Service Contact: Tel：0755-29832333(ext.2665), E-mail: [email protected]
Relative terms Rheological property: A sample distorts or flow when suffering external force; The term is mainly
represent the relationship among stress, shape change, deformation rate and viscosity.
Fluid: On suffering the shearing force, a sample with mobility deforms.
Newtonian fluid: A sample has constant viscosity under different shear rates. Mineral oil, water, honey, silicone oil and glycerol are all newtonian fluid.
Non-Newtonian fluid ： A sample whose viscosity depends on shear rate when measured is non-Newtonian fluid. It has plasticity, pseudoplastic and expansibility. Ceramic slurry, latex paint, cement, printing ink and silver paste are all non-Newtonian fluid.
Viscosity ： The resistance caused by shear or tensile stress which acts on the fluid. Yield point：The minimum stress which cause fluid to flow. Plasticity ： The property permanent deformation caused by the given stress acts on a fluid.
Thixotropy: Viscosity decreases when fluid suffers shear stress and increases without shear. It indicates the destruction in the structure of a sample. Rheopexy: Viscosity increases when fluid suffers shear stress and decreases after a time
Expansibility: The viscosity of a fluid suffering external force increases with increasing shear rate but return to a flow well status when the fluid is stewing. pseudoplastic: The viscosity of a fluid decreases with increasing flow rate grades.
Shenzhen Sunlord Electronics Co., Ltd.
Rev.B 2015 Service Contact: Tel：0755-29832333(ext.2665), E-mail: [email protected]
Analysis item
Qualitative analysis of fluid type according to the curve shape Viscosity decreases with increasing temperature
(green line)
Prediction of the force causing pasty to flow Prediction of the flow characteristic The yield point of the product is 80Pa. The sample has pseudoplastic and thixotropy properties.
Rheological behavior of a shampoo Rheological behavior of toothpaste The small thixotropy area indicates the internal structure is destroyed gently. The internal structure is destroyed apparently.
Viscosity
Shear rate
Shear rate
Shear stress
Shear rate
Shear rate
Viscosity
Shear stress
Shenzhen Sunlord Electronics Co., Ltd.
Rev.B 2015 Service Contact: Tel：0755-29832333(ext.2665), E-mail: [email protected]
The stabilizers used in dry blend processing of PVC The influence of temperatures on reaction rate of the sample. Pb-Stabi 3 #samples whose torque increased last is Cross-linking reaction began as soon as torque increases. the best choice. The rapid increase of torque indicates the rapid reaction.
Branched polymer
Linear polymer
The linear structure of molecular chain transform into 3D network. So the torque of the cross-linked polyethylene increased with increasing of viscosity.
Creep: The configuration and displacement of high polymer change under the action of external force. Stress relaxation: In the condition of constant strain, viscidity strain increases over time. Meanwhile, Springback strain decreases overtime. So the phenomenon of springback stress decreasing and slacking happens.
The viscosity of branched polymer increases under the action of low shear rate. Compared with linear polymer, branched polymer has more obvious shrear thinning behavior.