| Cationic polyacrylamide is a linear high-molecular polymer. The product is mainly divided into two forms: dry powder and colloid. According to its average molecular weight, it can be divided into three types: low molecular weight, medium molecular weight and high molecular weight. According to its structure, it can be divided into non-ionic, anionic and cationic. Anionic is mostly hydrolysate of PAM. The main chain of polyacrylamide has a large number of amide groups, which has high chemical activity. It can be modified to make many polyacrylamide derivatives. The product has been widely used in papermaking, beneficiation, oil extraction, metallurgy, building materials, sewage treatment, etc industry. Polyacrylamide is used as a lubricant, suspending agent, clay stabilizer, oil displacement agent, fluid loss reducing agent and thickener. It is obtained in drilling, acidification, fracturing, water plugging, cementing and secondary production, and tertiary production. It is widely used and is an important oilfield chemical. |
Effect of molecular weight on polyacrylamide viscosity
The viscosity of the polyacrylamide solution increases with the increase of the molecular weight of the polymer. This is because the viscosity of the polymer solution is generated by the interaction between molecules when the molecules move. When the relative molecular mass of the polymer is about 106, the polymer clusters begin to penetrate each other, which is sufficient to affect the scattering of light. At slightly higher levels, mechanical entanglement is sufficient to affect viscosity. When the content is relatively low, the polymer solution can be regarded as a network structure, and the mechanical entanglement between the chains and hydrogen bonds together form 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 tangles between the molecules, and the higher the viscosity of the solution.