Preparation of antimicrobial-wet strength polymer and its polyelectrolyte complex as novel functional additives

摘要

In this paper, novel polymers with synergistic wet strength and antimicrobial activity were synthesized by the condensation polymerization from hexamethylene diamine, diethylenetriamine and guanidine hydrochloride, followed by the crosslinking with epichlorohydrin. The formed four-membered azetidinium ring (AZR) is the effective group for developing wet strength of paper, meanwhile the guanidio group is the effective antimicrobial group due to its similarity to guanidine polymer. 2D heteronuclear correlation NMR spectroscopy (C-H COSY) was used to characterize the molecular structure of synthesized polymer. Minimum inhibition concentration (MIC), UV_(260) absorption and atomic force microscopy (AFM) were applied to reveal the antimicrobial effectiveness and morphological change of bacteria cells. Anionic carboxymethyl cellulose (CMC) was chosen to form polyelectrolyte complex (PEC) with the antimicrobial-wet strength polymer in an attempt to further increase wet strength and dry strength of paper. The characteristics of layer-by-layer assembly of PEC multilayers from antimicrobial-wet strength polymer and CMC was further revealed using AFM.