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Abstract: Transparent and conductive carbon nanotubes (CNTs)/polyurethane-urea (PUU) composite films were prepared by solvent evaporation-induced self-assembly (EISA). Pristine CNTs were treated with acids (H2SO4/HNO3 =3:1, v:v), acylated with thionyl chloride, and purified after filtration. These acylated CNTs (0.05wt.% in dimethylformamide, DMF) were deposited onto the 3-aminopropyl triethoxysilane (APTES)-modified glass substrate by DMF EISA at 100°C with the withdrawal rate of 3cm/h. The CNT layers of 200–400nm thicknesses were transferred to the PUU films by solution casting or resin transfer molding (RTM) at ambient temperature. Optical transmittances of the composite films were 60–75% at 550nm wavelength and their sheet resistances were 5.2×100–2.4×103 kΩ/square, and which varied significantly with type of CNTs and the transferring methods of CNT layers. [Copyright &y& Elsevier]

Abstract: Composites of conducting polythiophene (PTh) with the host filler multi-walled carbon nanotube (MWNT) have been synthesized by the in situ γ-radiation-induced chemical polymerization method at room temperature. The resultant cable-like morphology of the composite (PTh–MWNT) structures was characterized by field-emission–scanning electron microscopy with the energy dispersive spectroscopy, Fourier transform infrared, thermal gravimetric analysis, X-ray photoelectron spectroscopy, and transmission electron microscopy. The characterizations of the molecular structure of the PTh–MWNT composites indicated that interfacial entrapment occurred between the MWNT and PTh; and the MWNT functioned as a template for PTh polymerization. The standard four-point probe method was utilized for measuring the conductivity of the samples. The conductivity through the PTh–MWNT composites was much higher than the value obtained for the bulk PTh powders synthesized by the same method. The PTh–MWNT composites showed improved thermogravimetric stability compared to the PTh homopolymer in the temperature range 0–800°C. [Copyright &y& Elsevier]

Hybrid nanobiocomposite films are prepared using a solution casting by incorporating TEMPO cellulose nanofibrils (TOCNs) and carbon nanotubes (CNTs) into an aqueous solution of pullulan (PULL). The presence of CNT is confirmed by XRD characterization, and the prepared film shows an increased degree of crystallinity after the addition of TOCNs and CNT. The maximum degree of crystallinity value is obtained for CNT 0.5 % (59.64%). According to the Fourier-transform infrared spectroscopy, the shifts of the characteristic -OH peak of PULL occurred after the addition of TOCNs and aqueous CNT (3306.39 to 3246.90 cm−1), confirming interaction between the TOCNs, CNTs, and PULL matrix. The prepared films show enhanced material properties including higher tensile strength (65.41 MPa at low CNT content (0.5%)), water barrier properties, and reduced moisture susceptibility (5 wt.% CNT shows the lowest value (11.28%)) compared with the neat PULL film. Additionally, the prepared films are almost biodegradable within 64 days and show excellent electrical conductivity (0.001 to 0.015 S/mm for 0.5–5% CNT), which suggests a new approach to transform natural polymers into novel advanced materials for use in the fields of biosensing and electronics. [ABSTRACT FROM AUTHOR]

Abstract: Nanocomposites of gold and multi-walled carbon nanotubes (MWNTs) were prepared with gold nanoparticles and MWNTs stabilized by 4-(dimethylamino)pyridine (DMAP) and dispersion agents, respectively, and studied in detail with UV/vis spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). UV/vis spectra of Au-MWNT nanocomposites showed the characteristic surface plasmon bands at ∼525nm. There was only slight change on the band shape with change of dispersion agent for MWNTs. Through TEM images and XPS analysis, the distribution of gold nanoparticles on the sidewalls of MWNTs was deliberately investigated on three species of Au-MWNT nanocomposites treated with different dispersion agents and compared with one another. [Copyright &y& Elsevier]

Abstract: Gold-decorated multi-walled carbon nanotubes were prepared by electrostatic interaction in solution states and they have been studied in detail with UV/Vis spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). Gold nanoparticles and their composites showed the similar surface plasmon absorptions. XPS results were in good agreement with the composite morphologies of TEM images. HOMO/LUMO energies and the energy band gaps of MWNTs in their composites were analyzed by CV measurements. [Copyright &y& Elsevier]