Silver-loaded HDPE/clay nanocomposites with antibacterial property: A potential replacement for commodity polyethylene plastic

A silver intercalated clay based HDPE nanocomposite with excellent antibacterial activity has been reported for the first time. Antibacterial silver-clay (Ag-MMT) synthesized in laboratory was incorporated into HDPE to prepare antibacterial HDPE/Ag-MMT nanocomposites. Silver has been chosen as it is a powerful antimicrobial agent with additional properties such as unique optical, electrical, and thermal characteristics. The nanocomposites were fabricated through melt mixing route in a twin-screw extruder with varying Ag-MMT concentrations. Transmission electron microscopy, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction studies confirmed superior dispersion of clay platelets in HDPE. Dynamic oscillatory properties and mechanical characteristics of the nanocomposites were determined to observe the effect of Ag-MMT on HDPE. Antimicrobial testing of these nanocomposites against Gram-negative bacteria Escherichia coli O157:H7 and Gram-positive bacteria Staphylococcus aureus showed excellent bioactivity (>99%) at 5 wt% Ag-MMT. These antibacterial plastic materials have potential to replace neat HDPE products in niche areas where antimicrobial property would be highly desirable. POLYM. COMPOS., 39:E366-E377, 2018. (c) 2017 Society of Plastics Engineers