Adsorption of MA-Na copolymer at the ZnO-aqueous solution interface

Adsorption behaviors of maleic anhydride sodium salt copolymer on the zinc oxide surface were studied in aqueous suspensions. FTIR spectroscopic data provided evidence in support of hydrogen bonding and chemical interaction between the copolymer and ZnO. Adsorption density decreased with an increase of pH. Thickness of adsorption layer increased with the increase of pH and copolymer concentration. A detailed study of ionic strength effect showed that an increasing monovalent salt concentration resulted in the increase of adsorption density, while the density decreased with the further increasing salt concentration. The adsorption density in the presence of CaCl2 solution was greater than that in the NaCl solution of the same concentration. The shift of pHiep towards lower pH value was observed in the presence of MA-Na copolymer.