Composites of Single-Walled Carbon Nanotubes and Polystyrene: Preparation and Electrical Conductivity

Abstract

Composites of single-walled carbon nanotubes (SWNT) and polystyrene have been prepared using three different types of SWNT: HiPco, CoMoCat, and pulsed laser vaporization (PLV). Nanotubes were incorporated into the polystyrene matrix by two methods: (1) evaporation of chloroform solutions of SWNT noncovalently functionalized with poly[(m-phenylenevinylene)-co-(2,5-dioctoxy-p-phenylenevinylene)] (PmPV) and polystyrene; (2) coagulation in water of DMF solutions containing polystyrene and nitric acid oxidized SWNT. From measurements of the electrical conductivities of the composites over a range of concentration from 0.1 to 6 wt % SWNT, the percolation threshold of conductivity was 0.17-0.3% SWNT for the PmPV-coated materials and 0.4-0.5% for those made by coagulation. Of the three types of SWNT, composites made with HiPco tubes had the highest conductivity.

Temperature dependence of thermal conductivity enhancement in single-walled carbon nanotube/polystyrene composites

“…Considering the 1 mass % SWCNT/PS composites, the values in the Ohmic region are similar in magnitude to those reported by Tchoul et al 29 for several SWCNT/PS composites but low in comparison to 10 −6 S cm −1 reported for other 1 mass % SWCNT/PS composites by the Winey group. 23 Given the dramatic effect of dispersion, 22 large variability between samples prepared separately is not unexpected.…”

Preparation and properties of polystyrene incorporated with gold and silver nanoparticles for optoelectronic applications

“…Our results showed that the electrical resistivity of PS was decreased from 4.59 9 10 6 X cm to 3.7 9 10 5 X cm and to 2.1 9 10 5 X cm after inclusion of Ag and Au NPs, respectively. This result can be ascribed to (I) appearance of loose defect charges located at interface and to (II) the conducting process is dominated by the percolating paths, in parallel with other non-percolating paths (Tchoul et al 2008;Shockley and Read 1952).…”

Stiff and electrically conductive composites of carbon nanotube aerogels and polymers

“…In addition, dispersion methods can vary greatly depending on the characteristics of matrix material. [16][17][18][19][20][21][22][23][24][25] While measurable increases in electrical conductivity can be achieved through addition of as little as 0.007 wt% CNTs to polymer matrices, 5 preparation of composites with conductivities >1 S cm -1 requires either higher loadings of CNTs (>10 wt%) [7][8][9][10][11][12][13] or specially-designed CNTs that facilitate dispersion in the matrix. 25 Thus, the fabrication of CNTpolymer composites with conductivities on par with highly conductive semiconductors and metals for applications such as electromagnetic interference shielding can be an expensive endeavor.…”