What is the viscosity of polyacrylamide related to
It is normal for the viscosity of polyacrylamide of the same model to be different, but some polyacrylamides of the same model may also have different viscosity. Why? In fact, this is mainly caused by three aspects. Let us introduce you in detail below.
1. Molecular weight
When the molecules move, the objects will have viscosity due to their mutual movement. That is to say, the more molecules there are, the stronger the movement force between them will be. Macromolecular polyacrylamide means that the more molecules it will have, the more its viscosity will increase. Low-molecular polyacrylamide due to the low interaction between molecules, male and female will generally show a network structure, while high-molecular polyacrylamide due to the large interaction between the molecules, it will appear gel shape.
2. Hydrolysis time
The difference in hydrolysis time will also cause the viscosity of polyacrylamide to change, which is mainly caused by structural reasons. If the hydrolysis time is too short, the hydrolysis of polyacrylamide may not be complete, and the network structure cannot be completely formed in the water, resulting in insufficient viscosity. Of course, it is not that the longer the hydrolysis time, the higher the viscosity. If the hydrolysis time is too long, the viscosity of the polyacrylamide will also decrease. This is actually because polyacrylamide is decomposed into negatively charged molecules after being dissolved in water. At this time, it is possible to repel the anions between different chain links, causing the entanglement of the branches to cause the viscosity to decrease.
3. Temperature
Diffusion, friction, entanglement and other phenomena between molecules will have a great impact on the viscosity of molecules, and temperature will affect these to varying degrees. Under normal circumstances, the higher the temperature, the lower the viscosity of polyacrylamide. This is mainly because the network structure of polyacrylamide molecules will be destroyed when the temperature is too high, resulting in lower viscosity.
