Ionization of short polymethacrylic acid: titration, DLS, and model calculations

Adsorption of polyethyleneimine and polymethacrylic acid onto synthesized hematite

“…An analysis of plots shows, that the greatest adsorption is observed in pH 3. The reason for that is a fact, that in pH lower than pK a = 5.98 [26] degree of dissociation is significantly low, similarly to polyacrylic acid [27]. Macromolecules of PMA in acidic environment, until pH 5.98, have more undissociated groups -COOH compared to dissociated -COO − (Table 1) [28], while surface of Fe 2 O 3 is positively charged (pH pzc 8.5).…”

“…Those groups dissociate giving a negative charge to PMA chain. Polycarboxylic acids are often used as additions to detergents, thickening substances in cosmetics and medicines and in some types of liquid fuels [11]. Polymers of methacrylic acid are used as inhibitors of creation of limestone, in oil production, paper and textile industry, and water purification processes [12][13][14][15][16].…”

Preparation of chitosan nanoparticles using methacrylic acid

“…The zetapotential of CS-PMAA nanoparticles is also greatly influenced by the solution pH. Literature reports pKa values of 4.9 and 6.5 for PMAA [34] and CS [35], respectively. As a consequence, at pH < 4.6, nanoparticles prepared with 0.2% of CS have a positive zeta-potential, as the NH 2 groups of ionized CS become NH + 3 in this condition.…”

Compressibility of biotic sludges – An osmotic approach

“…As such, calculations will be based on a pK a value of 4.00. The dissociation constant for Na + is much higher than the dissociation constant for hydroxonium [28], and counterion condensation (Manning condensation) is not normal for weakly charged gels, such as EPS. At high Na + concentrations, counterion condensation can take place, but this effect has not been considered hereafter.…”