No abstract

Poly(vinyl alcohol) (PVA) composite films using poly(vinyl pyrrolidone) (PVP) and sodium dodecyl sulfate (SDS)-covered, well dispersed single wall carbon nanotubes (SWNT) exhibit significant improvement in tensile strength and modulus as compared to the control PVA and PVA/PVP/SDS films. The evidence of load transfer to the nanotubes in the composite film has been obtained from the shift in the Raman SWNT D* band peak position.

An optically homogeneous solution/dispersion of single-wall carbon nanotubes (SWNTs) in oleum has been used to form isotropic films exhibiting fibrillar morphology. Tensile modulus, strength, and strain to failure of the film are 8 GPa, 30 MPa, and 0.5%, respectively. The electrical conductivity in the plane of the film is 1 × 105 S/m.

No abstract

Polyacrylonitrile (PAN) fibers containing 10 wt.‐% single‐walled carbon nanotubes (SWNTs) exhibit a 100 % improvement in tensile modulus and reduced thermal shrinkage and polymer solubility. A 40 °C increase in glass transition temperature as compared to the control PAN fiber is also observed (see Figure). SWNT anisotropy has been observed using infrared spectroscopy.

Single wall carbon nanotube films (bucky paper) have been prepared using aqueous dispersions containing 0, 3, 6, and 10 M nitric acid. With increasing nitric acid concentration, film tensile strength increased from 10 to 74 MPa, tensile modulus from 0.8 to 5.0 GPa, while in-plane dc electrical conductivity decreased from 3 × 10 4 S/m to 1.2 × 10 4 S/m. In-plane storage modulus exhibited no decrease in the measured temperature range (room temperature to 200°C). Raman spectroscopy showed that nitric acid treatment results in the loss of the small diameter tubes. This was consistent with the X-ray diffraction observation, which showed that with increasing nitric acid concentration, (10) and (11) SWNT d spacings increased from 1.23 to 1.29 nm and from 0.74 to 0.87 nm, respectively. Morphological changes in the film have been monitored using scanning electron microscopy.

No abstract

No abstract