Product PerformanceEffects of simulation conditions on antibacterial performance of polypropylene and polystyrene doped with HPQM antibacterial agent

2-Hydroxypropyl-3-piperazinyl-quinoline carboxylic acid methacrylate (HPQM) antibacterial agent in two different forms, solid form (HPQM-supported Neusilin absorbance; HPQM-neu) and liquid form (HPQM dissolved in deionized water; HPQM-water), were added to polypropylene (PP) and polystyrene (PS). The antibacterial performance against Escherichia coli and mechanical properties of the specimens were investigated. The effects of simulated conditions, including immersion in water (at room temperature and 80 °C), immersion in surfactant solution (at room temperature and 80 °C) and exposure to UV aging, on the antibacterial performance of specimens were also studied. The results showed that the optimal HPQM concentration for PP/HPQM-neu and PP/HPQM-water were 500 and 750 ppm, respectively, in order to reach 99.9% E. coli bacteria reduction, but those for PS/HPQM-neu and PS/HPQM-water were 1250 ppm. Addition of HPQM in both forms to PP and PS did not change the mechanical performance. HPQM-water was more appropriate and effective for antibacterial peformance for PP and PS than HPQM-neu. Immersion of all specimens in water and detergent solution (at room temperature and 80 °C) and UV aging decreased the antibacterial performance at different rates, the effect being very pronounced for the specimens with HPQM-neu.