The dissolution process of polyacrylamide is swells first and then dissolves. The dissolution rate of polyacrylamide is related to its molecular weight, ionicity,product formulation, molecular geometry, , dissolution temperature, stirring and feeding methods.

1. Molecular weight

The dissolution rate slows down as the molecular weight increases and the degree of chemical crosslinking increases. The overall crosslinking will make the polyacrylamide only swell and not dissolve. In the manufacturing process of powder products, high drying temperature and long drying time will cause the product to melt partially or lightly crosslink and prolong the dissolution time or even partially insoluble matter.

2. Dosage form

The dissolution time of different polyacrylamide product formulations varies greatly. Typically it takes about 20-60 minutes for dissolution of products in form of powder, 20-60 minutes for hydrosol type (concentration 1 per cent -5 per cent), 3-5 minutes for emulsion type, and 5-10 minutes for water dispersion type. The polyacrylamide of solid powder is usually more soluble than the polyacrylamide of hydrosol plastic because the first one has a larger contact area with water. The dissolution rate increases with decreasing particle diameter in the 2.5 power relationship; loose solid powder of polyacrylamide dissolve more quickly than dense ones. The method of feeding the powder product is critical. The correct way is to gradually put the powder into the stirred water to prevent agglomeration. The dissolution time will be prolonged if the particles agglomerate. Polyacrylamide has a high water absorption rate, and powder products are prone to absorbing moisture or agglomerating in water, both of which must be avoided.

As one of top ten polyacrylamide manufacturers in China, Shandong Welldone can provide you with cationic, anionic and nonionic polyacrylamide, which could be used in various fields, including oil and gas, municipal and industrial water treatment, mining, paper and sugar industries. If you are interested, please feel free to contact us:jack.ma@welldonechina.com