Antimicrobial performance of polyethylene nanocomposite monofilaments reinforced with metal nanoparticles decorated montmorillonite

A comparative study on the antimicrobial behavior of high density polyethylene (HDPE) nanocomposite monofilaments based on three types of metal nanoparticles (NPs) decorated montmorillonite (MMT) has been presented. Modified MMT decorated with silver, copper and zinc oxide nanoparticles were synthesized in-lab and used as a reinforcing agent in preparing HDPE/modified MMT nanocomposite monofilaments via melt compounding and fiber spinning route in presence of compatibilizer. The concentration of modified MMT was varied from 1 to 5 wt. % in the nanocomposite monofilament. A mixture of intercalated and exfoliated morphology was observed from TEM and WAXD analyses with absence of clay agglomerations. DSC studies indicated MMT acting as heterogeneous nucleating agent with increased degree of crystallinity, crystallization temperature and rate of crystallization. The HDPE/modified MMT nanocomposite monofilaments showed remarkable decrease in bacterial colonies against Gram (-) E. coli and Gram (+) S. aureus with HDPE/Ag-MMT monofilaments showing the highest activity (> 99%). The dissolution kinetics of metal ions/NPs from modified MMT nanostructure was studied to understand its effect on antimicrobial action. The antimicrobial filaments are potential candidates to replace neat HDPE counterparts in moist environment applications such as ropes, sacks, agricultural items and geotextiles where microbial growth is a cause of concern.