Antimicrobial and Thermal-Responsive Layer-by-Layer Assembly Based on Ionic-Modified Guanidine Polymer and PVA

Water-soluble polymers, cationic polyhexamethylene guanidine hydrochloride (CPHGH) with antimicrobial property and acetalyzed poly(vinyl alcohol)/sodium acrylate (APVA-co-AANa) with temperature-responsive property were synthesized, and used as cationic and anionic polymer respectively to assemble multilayers to attempt to obtain a unique antimicrobial polymer system via the technique of layer by layer (LbL) assembly. The measurement of turbidity change for APVA-co-AANa aqueous solution under different temperatures revealed that the lower critical solution temperature (LCST) of APVA-co-AANa can be tailored by controlling the degrees of acetalysis (DA). Lower LCSTs were observed for the APVA-co-AANa with a higher DA. AFM images reveal that the particles on the surface of (CPHGH/APVA-co-AANa) and (PDADMAC/APVA-co-AANa) multilayers became larger after the material was treated at 60 C; while the roughness of the surfaces was increased as the layer number increase and then decrease. Moreover, antimicrobial test also proved that cellulose fiber assembled with (CPHGH/APVA-co-AANa) multilayers exhibited higher antimicrobial activity against coliform and staphylococcus aureus.