How does Anionic Polyacrylamide improve paper retention?
2026-04-14 10:24:10
Anionic Polyacrylamide(APAM)improves fiber and filler retention in papermaking mainly through adsorption bridging,charge neutralization,and floc formation,working either alone or in combination with cationic additives.
Adsorption and bridging effect
Long-chain APAM molecules adsorb onto fine fibers,fillers(calcium carbonate,talc,TiO₂),and other suspended particles,connecting many small particles into larger flocs.These larger flocs are more easily retained on the forming wire instead of passing through with whitewater.
Charge attraction and neutralization
APAM carries negative charges,while pulp fibers and many fillers often carry weak negative or positive charges under papermaking conditions.When used with cationic retention aids,APAM forms a dual-polymer system that effectively neutralizes surface charges,reduces repulsion,and promotes aggregation.
Reducing loss of fine components
Fine fibers and micro-fillers are the easiest components to lose during papermaking.APAM captures these tiny particles and binds them into the paper web,significantly increasing first-pass retention and reducing the load on whitewater recycling systems.
Improving formation uniformity
By properly flocculating fine materials,APAM avoids excessive agglomeration while preventing small-particle loss,resulting in more uniform paper formation and higher effective utilization of raw materials.
References
GB/T 7714
Ma W,Li H,Zhou Y.Mechanism of anionic polyacrylamide in improving filler and fiber retention in papermaking.Paper Science&Technology,2020,39(2):36–40.
MLA
Ma,Wei,et al."Mechanism of Anionic Polyacrylamide in Improving Filler and Fiber Retention in Papermaking."Paper Science&Technology,vol.39,no.2,2020,pp.36–40.
APA
Ma,W.,Li,H.,&Zhou,Y.(2020).Mechanism of anionic polyacrylamide in improving filler and fiber retention in papermaking.Paper Science&Technology,39(2),36–40.
