CHARACTERIZATION OF MELT-BLOWN FILTERS MADE OF POLYPROPYLENE AND POLYPROPYLENE-ANTIMICROBIAL BLENDS

Melt-blown filter media continuing antimicrobial compounds were evalua ted for mechanical properties properties, filtration efficiency, and a bility to prevent bacterial growth on the filter. The filters were cha llenged with gram-negative and gram-positive bacteria grown on agar at three levels of pH and incubated at 25 degrees C and 37 degrees C for 24 h and 48 h. Antimicrobial Compound A prevented growth of the gram- positive Staphylococcus aureus bacteria at pH 4.8. Compound A was inef fective against the gram-negative Klebsiella pneumoniae bacteria at an y pH. Compound B had no effect on bacterial growth. Compound C prevent ed growth of gram-negative and-positive bacteria at all pH levels. The antimicrobial compounds were nucleating agents, producing slight incr eases in crystallinity temperature, modulus, tensile strength, and str ess-at-break and a decrease in elongation-at-break. Fiber diameter inc reased with increasing concentrations of antimicrobial compounds. Filt ration efficiency decreased with increasing fiber diameter.