The viscosity of the polyacrylamide solution increases with the increase of the molecular weight of the polymer, because the viscosity of the polymer solution is generated by the interaction between the molecules during the movement of the molecules. When the relative molecular weight of the polymer is about 106, the polymer coils begin to penetrate each other, which is enough to affect the scattering of light. At slightly higher levels, mechanical entanglement is sufficient to affect viscosity. At fairly low levels, the polymer solution can be viewed as a network-like structure, with mechanical entanglements and hydrogen bonds between chains forming the nodes of the network. At higher levels, the solution contains many chain-link contacts, making the polymer solution gel-like. Therefore, the higher the relative molecular mass of the polymer, the easier it is to form chain entanglements between the molecules, and the higher the viscosity of the solution.
Post time: May-17-2022