Efficient functionalization of multi-walled carbon nanotubes with p -aminophenol and their application in the fabrication of poly(amide-imide)-matrix composites

Synthesis of Nanocomposites of V₂O5©Selenium Nanoparticles and Multiwalled Carbon Nanotubes for Antimicrobial Activity

The authors report the preparation of the nanocomposite comprising of vanadium pentoxide (V₂O₅) and selenium (Se) nanoparticles and functionalized multiwalled carbon nanotubes (MWCNTs) (V₂O₅@Se NPs/MWCNTs). Since Se NPs possesses extraordinary physicochemical properties including larger surface area with higher adsorption capacity, V₂O₅ NPs were adsorbed onto Se NPs surface through physisorption process (designated as V₂O₅@Se NPs). The nanocomposite synthesized hydrothermally was evaluated for its antimicrobial activity. The morphology and microstructure of the nanocomposite were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, respectively. Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy (UV-Vis) were employed to analyze the spectral properties of nanocomposite. The microbicidal efficacy of nanocomposite was tested against Gram-negative (G-)ZGram-positive (G+) bacteria and fungus. This is the first report on the synthesis of V₂O₅@Se NPs/MWCNTs nanocomposites by chemical method that showed microbicidal effect on micro-organisms. The thiol (-SH) units facilitates the enrichment of V₂O₅@Se NPs onto MWCNTs surface. Ultimately, it reflects on the significant antimicrobial activity of V₂O₅@Se NPs/MWCNTs.

Investigation of thermal and tensile properties of poly(benzimidazole-imide) composites incorporating salicylic acid–functionalized multiwalled carbon nanotubes

This work describes a novel aromatic poly(benzimidazole-imide) (PBII) with amino salicylic acid (ASA) segments in the main chain by melt/solid polymerization method under solvent-free conditions and its composites reinforced with ASA-functionalized multiwalled carbon nanotubes (MWCNTs-ASA). The polymer was obtained in high yield with an amorphous morphology, was soluble in various organic solvents, such as N,N′-dimethylacetamide, N,N′-dimethylformamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide, and could afford flexible and tough film via solution casting. MWCNT-ASA/PBII composite films were also prepared by casting a solution of precursor polymer containing different fractions of MWCNTs-ASA into a thin film (1, 2, and 5 wt%). The cast films exhibited good mechanical properties with tensile strengths of 90.00–128.3 MPa, elongation at break of 4.6–7.9%, and tensile modulus of 1.6–2.9 GPa. They were reasonably stable up to a temperature above 400°C for the PBII and above 450°C for the composites. Structural and morphological evaluation of the composites was carried out by Fourier transform infrared spectroscopy and X-ray diffraction. Dispersion of MWCNT-ASA in the polymer matrix was investigated by field emission scanning and transmission electron microscopy.

Surface functionalization of carbon nanotubes: fabrication and applications

This review highlights recent development in functionalization of CNTs and their applications.

Preparation and properties of high-performance poly(amide–imide) composite films based on glucose-functionalized multiwalled carbon nanotubes

Glucose has been covalently linked to multiwalled carbon nanotubes (MWCNTs). After that, the modified MWCNTs were added to a poly(amide–imide) (PAI) matrix. PAI-based composites were fabricated by an ex situ blending technique with 5, 10, and 15% of loading by weight. The composite hybrid films were prepared by a solvent-casting method. The structural properties of all hybrids have been characterized using a large variety of spectroscopic and microscopic techniques. It was found that the functionalization of MWCNTs could improve their dispersion and interfacial adhesion to the PAI matrix. The thermal stability of the MWCNT/PAI composite films was improved due to excellent dispersion of MWCNT in the polymer matrix. Tensile tests on the composites showed an increase in the elastic modulus and the yield strength and a decrease in the failure strain.