Polyolefin Microfiber Based Antibacterial Fibrous Membrane by Forced Assembly Coextrusion

There is a burgeoning demand for polyolefin based fibrous membranes with antibacterial properties due to the increasing awareness about recyclable materials for air and water purification. This paper presents a systematic study on the development of dual component, polypropylene (PP), and high density polyethylene (HDPE) fibrous membranes based on a continuous coextrusion and multiplication manufacturing technique. Chlorhexidine dihydrochloride (CHDH), an organic low molecular weight antibacterial additive, is melt-compounded to impart antibacterial characteristics to the fibrous membranes. The PP/HDPE membranes are hydrophobic and possess 77% porosity, whereas inclusion of CHDH increases the porosity to 91% and the surface area increases almost twofold. In addition, the membranes possess a mean flow pore size of 7 μm. ATR-FTIR study on the PP/CHDH/HDPE membranes indicate the presence of CHDH on the fiber surface, which imparts antibacterial character to the membrane. Investigations carried out on the CHDH containing PP/HDPE fibrous membranes using E. Coli indicate that the presence of CHDH on the fiber surface results in a bacterial growth inhibition zone on solid growth media. In addition, quantitative studies result in the complete reduction of colony forming units after 4 h of contact time.