Mechanical, dielectric, thermal and antibacterial properties of reduced graphene oxide (rGO)-nanosized C3AH6 cement nanocomposites for smart cement-based materials

rGO densification prior to polymer compounding affects the composite printability and physicochemical properties, which also depend on rGO concentration. The resulting scaffolds support cell viability and osteogenesis, and possess antibacterial properties.

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Enhanced Mechanical and Antibacterial Properties of Nanocomposites Based on Poly(vinyl Alcohol) and Biopolymer-Derived Reduced Graphene Oxide

Polymers ◽

10.3390/polym13040615 ◽

2021 ◽

Vol 13 (4) ◽

pp. 615

Author(s):

Beom-Gon Cho ◽

Shalik Ram Joshi ◽

Seongjin Lee ◽

Shin-Kwan Kim ◽

Young-Bin Park ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Vinyl Alcohol ◽

Bacterial Colonization ◽

Low Cost ◽

Critical Concentration ◽

Antibacterial Properties ◽

Single Step ◽

Poly Vinyl Alcohol ◽

Reduced Graphene

Functionalized graphene–polymer nanocomposites have gained significant attention for their enhanced mechanical, thermal, and antibacterial properties, but the requirement of multi-step processes or hazardous reducing agents to functionalize graphene limits their current applications. Here, we present a single-step synthesis of thermally reduced graphene oxide (TrGO) based on shellac, which is a low-cost biopolymer that can be employed to produce poly(vinyl alcohol) (PVA)/TrGO nanocomposites (PVA–TrGO). The concentration of TrGO varied from 0.1 to 2.0 wt.%, and the critical concentration of homogeneous TrGO dispersion was observed to be 1.5 wt.%, below which strong interfacial molecular interactions between the TrGO and the PVA matrix resulted in improved thermal and mechanical properties. At 1.5 wt.% filler loading, the tensile strength and modulus of the PVA–TrGO nanocomposite were increased by 98.7% and 97.4%, respectively, while the storage modulus was increased by 69%. Furthermore, the nanocomposite was 96% more effective in preventing bacterial colonization relative to the neat PVA matrix. The present findings indicate that TrGO can be considered a promising material for potential applications in biomedical devices.

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Antibacterial Performance of a Mussel-Inspired Polydopamine-Treated Ag/Graphene Nanocomposite Material

Materials ◽

10.3390/ma12203360 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3360

Author(s):

Jianming Liao ◽

Shuaiming He ◽

Shasha Guo ◽

Pengcheng Luan ◽

Lihuan Mo ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Antibacterial Properties ◽

Great Promise ◽

X Ray ◽

Antibacterial Performance ◽

Reduced Graphene ◽

Wide Range ◽

Graphene Nanocomposite

Graphene-based nanocomposites have attracted tremendous attention in recent years. In this study, a facile yet effective approach was developed to synthesize reduced graphene oxide and an Ag–graphene nanocomposite. The basic strategy involved in the preparation of reduced graphene oxide includes reducing graphene oxide with dopamine, followed by in situ syntheses of the Ag-PDA-reducing graphene oxide (RGO) nanocomposite through adding AgNO3 solution and a small amount of dopamine. The nanocomposite was characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FTIR spectra, Raman spectra, ultraviolet-visible (UV-vis), and X-ray photoelectron spectroscopy (XPS), results indicated that a uniform PDA film is formed on the surface of the GO and GO is successfully reduced. Besides, the in situ synthesized Ag nanoparticles (AgNPs) were evenly distributed on the RGO surface. To investigate antibacterial properties Ag-PDA-RGO, different dosages were selected for evaluating the antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. The Ag-PDA-RGO nanocomposites displayed excellent antibacterial property. The antibacterial ratio reached 99.9% against S. aureus and 90.9% against E. coli when the dosage of 100 mg/L Ag-PDA-RGO nanocomposites was 100 μL. The novel Ag-PDA-RGO nanocomposite prepared by a facile yet effective, environmentally friendly, and low-cost method holds great promise in a wide range of modern biomedical applications.

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