Composites of uniaxially oriented multiwalled carbon nanotubes embedded in
polymer matrices were fabricated and investigated by transmission electron
microscopy. In strained composite films, buckling was ubiquitously observed
in bent nanotubes with large curvatures. By analyses of a large number of
bent nanotubes, the onset buckling strain and fracture strain were estimate
d to be approximate to 5% and greater than or equal to 18%, respectively. T
he buckling wavelengths are proportional to the dimensions of the nanotubes
. Examination of the fracture surface showed adherence of the polymer to th
e nanotubes. (C) 1999 American Institute of Physics. [S0003-6951(99)05222-5
].