How to Prevent Hydrolysis of PAM Polyacrylamide?

Anionic polyacrylamide has a polar amide group that easily adsorbs to the surface of sediment particles through hydrogen bonding. In addition, Anionic polyacrylamide Flocculant has a long molecular chain and a huge adsorption area in water, providing excellent flocculation effect. It can also bridge between floc particles with long chains to form large floc particles, accelerating settlement. Professional manufacturers produce high-quality water treatment agents.

Hydrolysis of PAM polyacrylamide

PAM polyacrylamide is easily hydrolyzed by alkalis such as sodium hydroxide, resulting in the generation of some polyacrylate sodium. Polyacrylate sodium molecules in water are unstable and dissociate into RCOO-Na+. Therefore, hydrolyzed polyacrylamide is a copolymer of PAM polyacrylamide and polyacrylate sodium. Because of the action of RCOO (hydroxyl), hydrolyzed polyacrylamide becomes an anionic polymer flocculant, while non-hydrolyzed polyacrylamide flocculant is a non-ionic polymer flocculant. From the above hydrolysis process, it can be seen that partially hydrolyzed polyacrylamide products have a certain ammonia odor, making it easy to distinguish whether the PAM polyacrylamide products are hydrolyzed.

Partial hydrolysis of PAM polyacrylamide results in a change in polymer properties from non-ionic to anionic

Under the ion electrostatic repulsion of the RCCO (hydroxyl) functional group, the curved molecular chain on the main chain of PAM polyacrylamide expands and elongates, increasing its adsorption surface area and improving its bridging ability. Therefore, the flocculation effect of partially hydrolyzed polyacrylamide is better than non-ionic polyacrylamide.

Generally, Anionic polyacrylamide used for treating highly turbid water should be partially hydrolyzed. The settling rate of highly hydrolyzed polyacrylamide (hydrolysis degree refers to the percentage of amide groups converted to hydroxyl groups in the PAM polyacrylamide molecule) is 2 to 9 times that of non-hydrolyzed polyacrylamide. However, the flocculation effect of Anionic polyacrylamide with excessively high or low degree of hydrolysis is not ideal because it weakens the adsorption bridging ability of low-hydrolyzed polyacrylamide and increases the repulsion ability to soil particles of highly hydrolyzed polyacrylamide. After numerous experiments, it was determined that the ultra-high hydrolysis degree of anionic polyacrylamide flocculant should range from 20% to 25%.

To prevent the hydrolysis of PAM polyacrylamide, attention should be paid to the following points

• Do not put it in an iron, and the temperature should not exceed 60 degrees.

• The mixing speed should not be too fast, which may cause damage to the molecular structure.
  

• It is better to use it immediately after storage for a certain period. When used in conjunction with other drugs, the order of addition should be noted.