TY - GEN
T1 - Homogeneous dispersion of the surface modified MWNTs in the PU matrix and electrical conductivity of the MWNTs/PU composites
AU - Kim, Yoon Jin
AU - Jang, Yong Gyun
AU - Choi, Jun Whan
AU - Yoon, Ho Gyu
PY - 2004
Y1 - 2004
N2 - Dispersion characteristics of the surface modified MWNTs (Miltiwalled nanotubes) in the PU (polyurethane) matrix and electrical conductivity of the MWNTs/PU composites are investigated using SEM and DEA (Dielectric analyzer) with respect to the chemical treatment of MWNTs, the kind of surfactants and their content. Several chemical treatments of the MWNTs' surfaces were performed with the acids type, acidic concentration, treatment temperature, and oxidation time. All the surface of modified MWNTs are negatively charged and functionalized with carboxylic group; however, the external walls of some MWNTs were severely damaged so that they were frequently thinned and partially cracked. Compared to those of the composites without the addition of surfactant, the surfactant embedded into composites show much better dispersion of the MWNTs and higher electrical conductivity, these results are in good agreement with the two step adsorption model of cationic surfactants proposed by Y. Gao. Both the optimized MWNTs and cationic surfactant filled PU composites show very low percolation threshold, pc = 0.0089± 0.007 vol. %, and relatively higher conductivity after percolation than other carbon nanotubes composite systems reported elsewhere.
AB - Dispersion characteristics of the surface modified MWNTs (Miltiwalled nanotubes) in the PU (polyurethane) matrix and electrical conductivity of the MWNTs/PU composites are investigated using SEM and DEA (Dielectric analyzer) with respect to the chemical treatment of MWNTs, the kind of surfactants and their content. Several chemical treatments of the MWNTs' surfaces were performed with the acids type, acidic concentration, treatment temperature, and oxidation time. All the surface of modified MWNTs are negatively charged and functionalized with carboxylic group; however, the external walls of some MWNTs were severely damaged so that they were frequently thinned and partially cracked. Compared to those of the composites without the addition of surfactant, the surfactant embedded into composites show much better dispersion of the MWNTs and higher electrical conductivity, these results are in good agreement with the two step adsorption model of cationic surfactants proposed by Y. Gao. Both the optimized MWNTs and cationic surfactant filled PU composites show very low percolation threshold, pc = 0.0089± 0.007 vol. %, and relatively higher conductivity after percolation than other carbon nanotubes composite systems reported elsewhere.
UR - http://www.scopus.com/inward/record.url?scp=34249930829&partnerID=8YFLogxK
U2 - 10.1557/proc-858-hh3.25
DO - 10.1557/proc-858-hh3.25
M3 - Conference contribution
AN - SCOPUS:34249930829
SN - 1558998101
SN - 9781558998100
T3 - Materials Research Society Symposium Proceedings
SP - 105
EP - 109
BT - Functional Carbon Nanotubes
PB - Materials Research Society
T2 - 2004 MRS Fall Meeting
Y2 - 29 November 2004 through 2 December 2004
ER -