Adsorption of Starch on Cellulose and Pigments

Cationic starch is mainly adsorbed by the small fiber fractions and filler particles, according to their high specific surface. At low cationic starch levels (0.5%), only the small fiber fraction is saturated and rendered cationic a mosaic system is established which results in small flocks and good retention, but poor drainage. Increasing the 

Cationic potato starch is actually an amphoteric starch due to the presence of phosphate groups. An increase in cationic charge results when phosphate groups pro-tonate or react with aluminum ions in an acid papermaking system. Anionic phosphate starch will adsorb on cellulose, depending on pH and concentration in solution.135,138 

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