Synthesis and properties of polymeric biocides based on poly(ethylene-co-vinyl alcohol)

Poly(ethylene-co-vinyl acetate) with 55 wt % vinyl acetate units (EVA55) was cryogenically ground and saponified in KOH/ethanol solution to obtain poly(ethylene-co-vinyl alcohol) (EVOH55). Polymeric antimicrobial agents were synthesized by reacting three antimicrobial agents, 4-aminobenzoic acid (ABA), salicylic acid (SA), and 4-hydroxy benzoic acid (HBA) with EVOH55. The polymers became more flexible and exhibited lower melting peak temperature and heat of fusion as the content of the chemically bound ABA, SA, and HBA units increased. These phenomena appeared more significant in the order of ABA < HBA < SA. S. aureus, Gram-positive bacterium, was more susceptible to the polymeric antimicrobial agents than P. aeruginesa, Gram-positive bacterium. The antimicrobial activity increased in the order of EVOH55-HBA < EVOH55-ABA < EVOH-SA. (C) 2004 Wiley Periodicals, Inc.