Enhancing antibacterial properties of polypropylene/Cu‐loaded montmorillonite nanocomposite filaments through sheath–core morphology

Abstract

Polypropylene (PP) loaded with copper-exchanged montmorillonite (Cu-MMT) nanocomposite filaments and films with excellent antimicrobial activity have been reported for the first time. A sheath-core morphology filament in which only the sheath contains Cu-MMT was prepared for maximizing bioactivity. Sodium MMT clay was modified to acid-activated MMT and further to Cu-MMT via an ion exchange process. The exchange operation was confirmed using wide-angle X-ray diffraction and energy-dispersive X-ray spectroscopy (EDX) which suggested increased interlayer spacing and confirmed the loading of copper in Cu-MMT. Further, Cu-MMT was melt-mixed in PP in the form of PP/Cu-MMT nanocomposite filament, film and sheath-core morphology PP/Cu-MMT nanocomposite filament. The surface morphology and elemental composition of the nanocomposites were studied using scanning electron microscopy coupled with EDX. Transmission electron micrographs were obtained to understand the dispersion characteristics of Cu-MMT phase in PP. X-ray diffraction analysis of nanocomposites suggested increased crystallinity at lower loading due to heterogeneous nucleating action of MMT. The PP nanocomposite filaments and films were tested for antimicrobial activity against Gram-negative bacterium Escherichia coli, which is the main pathogenic bacterium found abundantly in water, and were found to exhibit excellent antimicrobial activity.

Development of novel segmented-pie microfibers from copper-carbon nanoparticles and polyamide composite for antimicrobial textiles application

“…34 Copper-loaded PA6/CuCNP microfibers were expected to exhibit excellent antibacterial activity in the inhibition zone test. 8,11 However, the results showed that the CuCNP-containing PA6 fabrics had no obvious inhibition zone against S. aureus and E. coli before or after being laundered 10 times (Figure 7). This can possibly be ascribed to the low copper content at the fiber surface and the low solubility and diffusion rate of CuCNPs.…”

Dual functionalized copper nanoparticles for thermoplastics with improved processing and mechanical properties and superior antibacterial performance

“…, along with the concentrations of antibacterial agents. 14,15,21,44–48 Apparently, the copper nanoparticles and their antibacterial composites synthesized by the method described herein are characterized by low copper addition and high antibacterial activity.…”

“…5d depicts the antibacterial properties of PP-based antibacterial composites with various antibacterial agents, including metals, oxides, metals/oxides, etc., along with the concentrations of antibacterial agents. 14,15,21,[44][45][46][47][48] Apparently, the copper nanoparticles and their antibacterial composites synthesized by the method described herein are characterized by low copper addition and high antibacterial activity.…”

Preparation of 3‐pentadecylphenol‐modified cellulose nanocrystal and its application as a filler to polypropylene nanocomposites having improved antibacterial and mechanical properties

“…[80][81][82] A lot of approaches have been performed to develop PP based polymeric materials having the antibacterial property. For example, inorganic particles including copper, 83 silver, [84][85][86] titanium oxide, 87 and zinc oxide 88 have been used as the antibacterial fillers although the deterioration of mechanical properties 84 and the elution of toxic particles 89 are known as the disadvantages. Since the antibacterial activity of CNC 90,91 and PDP [39][40][41] had been reported before, the antibacterial property of PP/CNC and/or PP/f-CNC was expected.…”