尼龙6/石墨纳米导电复合材料的制备与性能

通过原位插层聚合制备了尼龙 6 /石墨纳米导电复合材料 ,其室温导电渗滤阈值为 =0 75vol% ,远远低于常规导电粒子填充的聚合物复合材料 .当石墨体积分数为 2 0vol%时 ,室温电导率可达 10 -4 S/cm .透射电镜研究表明 :由于石墨经高温膨胀后其片层被剥离导致了片状石墨粒子具有巨大的径厚比 ,经原位插层聚合其片层厚度进一步被剥离为几十个纳米 ,同时原位插层聚合使得石墨粒子能够均匀分散在尼龙 6基体中 ,因而导致了该导电复合材料的低渗滤阈值和高导电性能 .

PREPARATION AND PROPERTIES OF NYLON 6/GRAPHITE NANOCOMPOSITE

Electrically conducting nylon 6/graphite nanocomposites were elaborated via intercalation polymerization.Room temperature electrical conductivity measurement reveals a threshold of *=0\^75 vol% which is much lower than that of conventional conducting polymer composites.The electrical conductivity of the nanocomposite reaches 10\{-4\} S/cm at 2\^0 vol% graphite content.The TEM microphotographs verified that the low percolation threshold and improvement of conductivity could be attributed to the large diameter to thickness ratio,the high expansion ratio in c axis of the graphite sheets and the homogeneously dispersion of graphite particles with nanoscale thickness in the nylon 6 matrix.Because of the high expansion ratio (generally 200～300) of expanded graphite in c axis there are many pores of different sizes ranging from 10nm to 10μm in the internal space of graphite.Thus suitable monomer molecules and/or catalysts can be easily intercalated into the gallery spaces of graphite through physical adsorption.This is the main reason that in-situ polymerization can be initiated in the galleries of expanded graphite.