Polyoctenamer - Single Walled Carbon Nanotube Composites: Spectroscopic Investigations

Abstract

Composites of single walled carbon nanotube dispersed within polymeric matrices have been investigated by spectroscopic techniques (Raman and Wide Angle X-Ray Spectroscopy). Raman investigations included an in depth analysis of the radial breathing mode (for single wall carbon nanotubes) and a brief analysis of the lines originating from the polymeric matrix. Raman spectra were successfully simulated by computer assuming that the as recorded spectrum is a convolution of lines whose line shape is well described by a modified Breit-Wigner-Fano equation. The dependence of the position of the lines belonging to the radial breathing mode on the concentration of single walled carbon nanotube has been investigated, with emphasis on information pertinent to the stress transfer from the macromolecular matrix to the filler and to the coating of single walled carbon nanotube by polymeric chains. Complementary Wide Angle X-Ray Spectroscopy measurements provided information about the effect of the loading with single walled carbon nanotube on the crystal structure of the polymeric matrix. The research aims to a better understanding of the interactions between polymeric matrices and nanofillers.

Interphase of polyoctenamer‐single‐wall carbon nanotubes by thermogravimetric analysis in air

“…The D line of SWNTs (associated with defects) was noticed within the expected range of Raman shifts 41 (at about 1305 cm −1 compared with the reported value of about 1351 cm −1 ), suggesting strong interactions. The main G line (associated with graphite structures) is located at 1581 cm −1 and is almost not affected by the loading with SWNTs.…”

“…As shown in Figure 8b, the position of RTM modes is shifting towards lower values as the carbon nanotube loading is increased, thus revealing an increase in the nanotube diameter. This strong shape distortion originates from C-C stretching vibrations within the SWNTs 42 and eventually between C atoms of the polymer The D line of SWNTs (associated with defects) was noticed within the expected range of Raman shifts 41 (at about 1305 cm À1 compared with the reported value of about 1351 cm À1 ), suggesting strong interactions. The main G line (associated with graphite structures) is located at 1581 cm À1 and is almost not affected by the loading with SWNTs.…”

“…This line exhibits a weak shift to larger Raman shifts as the concentration of SWNT is increased, suggesting that the nanotubes are distorted and eventually do not close seamlessly in a cylinder at low concentrations of nanofiller. It was shown that the increase of the position of the RBM mode as the SWNTs content is increased reflects a decrease in the diameter of SWNTs, 41 due to strong interactions. The increase of nanofiller concentrations facilitates the healing of nanotubes, as they are transiting to an ideal tube.…”

Diameter dependence of hybrid shish‐kebab structure in polyethylene/carbon material fiber composites

“…Some graphitic nanostructures such as carbon nanotubes, nano carbon fibers, and graphene nanosheets could repress the energy barrier for polymer crystallization by offering sufficient heterogeneous nucleation sites . Therefore, they are often served as heterogeneous nucleating agents for various semicrystalline polymers and these nanostructures can obviously change the crystallization kinetics and crystalline morphology.…”

UV Surface Treatment of Polycarbonate for Ad-hesion Improvement to Liquid Silicone Rubber (LSR)

“…If the UVC irradiation leads to lasting division of the carbonyl bond, the molecular weight drops due to shortening of the chain. Phenoxy and phenyl radicals form as cleavage products in the first step [27,28]. The formation of phenoxy radicals occurs five times more often [29].…”