What is the degree of hydrolysis of Anionic Polyacrylamide?
2026-04-14 10:15:14
Degree of hydrolysis(DH)—also called anionicity or charge density—is the percentage of amide groups(-CONH₂)on the APAM molecular chain that have been hydrolyzed into negatively charged carboxylate groups(-COO⁻).It directly controls charge density,solubility,flocculation behavior,and pH compatibility.
Standard Commercial Ranges&Grades
Typical industrial DH:5%–40%,commonly graded as:
Low DH:12%–15%/17%–19%
Low negative charge;better in acidic/high hardness/high salinity water;slower settling but stable in harsh electrolytes.
Medium DH:23%–27%(most common/general purpose)
Balanced charge&bridging;works well in neutral–alkaline municipal/industrial wastewater.
High DH:30%–37%
High negative charge;strong flocculation&fast settling for inorganic suspensions(mining,coal washing,kaolin);best in neutral–alkaline conditions.
Key Effects of DH
Higher DH=more negative charge=better for positively charged inorganic particles.
Lower DH=more resistant to salt/hardness=better in acidic/high electrolyte water.
DH>40%tends to reduce viscosity and floc strength.
Measurement&Nomenclature
Expressed as mole%or weight%.
Often labeled as:15%,20%,25%,30%,35%hydrolysis.
References
GB/T 7714
Wang Y,Li J,Zhou C.Hydrolysis degree control and application performance of anionic polyacrylamide.Industrial Water Treatment,2019,39(8):1–5.
MLA
Wang,Yan,et al."Hydrolysis Degree Control and Application Performance of Anionic Polyacrylamide."Industrial Water Treatment,vol.39,no.8,2019,pp.1–5.
APA
Wang,Y.,Li,J.,&Zhou,C.(2019).Hydrolysis degree control and application performance of anionic polyacrylamide.Industrial Water Treatment,39(8),1–5.
