Greatly improved adsorption of N‐methylated modified macroporous cross‐linked polyacrylamide toward tannin from aqueous solution

Macroporous cross-linked poly(N-methylacrylamide) (PMAM) was prepared and the adsorption behaviors of PMAM toward tannin from aqueous solution was studied in comparison with polyacrylamide (PAM). The swollen property indicated that PMAM had a higher hydrophobicity than PAM while the adsorption showed that PMAM had a greatly improved adsorption toward tannin. The adsorption data could be fitted well by Freundlich model and the values of the thermodynamic parameters of PMAM toward tannin were more negative than PAM. The multiple hydrogen bonding and hydrophobic interaction between PAM/PMAM and tannin were shown to be responsible for the adsorption, whereas a stronger hydrogen bonding and a higher hydrophobicity of PMAM had a contribution to the greatly improved adsorption of PMAM toward tannin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.