ZHANG Ling, HU Bin, LI Chunzhong. DISPERSION AND CRYSTALLIZATION BEHAVIOR OF POLYPROPYLENE NANCOMPOSITES WITH NUCLEATING AGENT MODIFIED MULTIWALL CARBON NANOTUBES. [J]. Acta Polymerica Sinica (12):1374-1381(2011)
DOI:
ZHANG Ling, HU Bin, LI Chunzhong. DISPERSION AND CRYSTALLIZATION BEHAVIOR OF POLYPROPYLENE NANCOMPOSITES WITH NUCLEATING AGENT MODIFIED MULTIWALL CARBON NANOTUBES. [J]. Acta Polymerica Sinica (12):1374-1381(2011) DOI: 10.3724/SP.J.1105.2011.10358.
DISPERSION AND CRYSTALLIZATION BEHAVIOR OF POLYPROPYLENE NANCOMPOSITES WITH NUCLEATING AGENT MODIFIED MULTIWALL CARBON NANOTUBES
Non-colavent modification of multiwall carbon nanotubes (MWCNTs) by arylamides compound -nucleating agent (-NA) through - interaction was found to improve the dispersion of MWCNTs in the polypropylene (PP) matrix
increase the crystallinity of PP
decrease the crystal size
and increase the electrical conductivity of their composites.The morphology
crystallization behavior and the electrical conductivity of the nanocomposites were investigated by field emission scanning electron microscopy (FESEM)
wide-angle X-ray diffraction (WAXD) and properties test.The characterizaiton of -NA-MWCNTs showed that -NA was successfully adsorbed on the surfaces of MWCNTs.The incorporation of -NA-MWCNTs results in the formation of rich -form crystals for PP
higher crystallinity and smaller crystalline sizes.FESEM observation showed that homogeneous compact network structure of -NA-MWCNTs was obtained due to the smaller and more uniform crystalline region.Consequently
the PP/-NA-MWCNTs nanocomposites possess a high electrical conductivity and a low percolation threshold of 0.3 wt% -NA-MWCNTs
which is associated with the homogeneous compact network structure of -NA-MWCNTs.The electrical conductivity of PP/-NA-MWCNTs (5 wt%) was up to 4.010-3 S/cm
which was 3 and 11 orders higher than that of PP/MWCNTs and PP
respectively.The effect of the crystalline size on the electrical conductivity of the nanocomposites was studied by isothermal crystallization method.The electrical conductivity of PP/-NA-MWCNTs was increased at first and then decreased with increasing time of isothermal crystallization.And the more MWCNTs added
earlier the maximum conductivity of PP/-NA-MWCNTs appeared.At the same content of MWCNTs
the isothermal time for the maximum conductivity at 140℃ was longer than that at 130℃.The results imply that high electrical conductivity with optimal MWCNTs network structure can be obtained by controlling the crystallization conditions.