New promising antimicrobial material based on thermoplastic polyurethane modified with polymeric biocide polyhexamethylene guanidine hydrochloride

New antimicrobial polymer composite based on commercial polyurethane (PU) Laripur®LPR9020 and polymeric biocide polyhexamethylene guanidine hydrochloride (PHMG-Cl) has been prepared by solvent casting method. Modified PU films containing from 1 to 4 wt% of PHMG-Cl were characterized in terms mechanical, thermal surface properties, release behavior, as well antibacterial activity against Gram-negative (Escherichia coli) Gram-positive (Bacillus subtilis) bacterial strains. The results mechanical testing indicate that the introduction did not cause noticeable changes tensile strength films, but improved their elasticity at least 20–30%. PU/PHMG-Cl was found possess significantly higher hydrophobicity than neat is manifested sharply increased water contact angle value 72° for 95° (2%). According thermogravimetric analysis data, composites are thermally stable 300 °C which availability melt processing common methods. differential scanning calorimetry showed reduction both glass transition melting temperatures more 7 when contained only 1% PHMG-Cl. Gradual modified into detected spectrophotometrically. total ratio be range 29% 48% after 50 hours immersion, depending its content composite. much lower leaching rate physiological saline solution compared pure (from 10% 21% hours), may caused poor solubility sodium chloride solutions. study using disc agar diffusion methods high efficacy tested microorganisms 3% biocide. So, this approach, modification resin with PHMG-Cl, discussed potential medical applications system or active material necessary.