A series of chitosan samples spanning a wide range of molecular weights hav
e been homogeneously acetylated to varying degrees and characterized. These
have been used to flocculate a well-characterized "model colloid" polymer
latex. The optimum flocculation concentrations have been identified using b
oth residual turbidity and initial-rate methods. A charge neutralization me
chanism with an enhancement of rate by a "charge patch" effect is shown to
operate while both degree of acetylation and molecular weight dan have an e
ffect upon the optimum flocculation concentration.