Alignment of carbon nanotubes in a polymer matrix by mechanical stretching

We report a method to fabricate polymer-based composites with aligned carbon nanotubes, and a procedure to determine the nanotube orientation and the degree of alignment. The composites were fabricated by casting a suspension of carbon nanotubes in a solution of a thermoplastic polymer and chloroform. They were uniaxially stretched at 100 degrees C and were found to remain elongated after removal of the load at room temperature. The orientation and the degree of alignment were determined by x-ray diffraction, The dispersion and the alignment of the nanotubes were also studied by transmission electron microscopy. (C) 1998 American Institute of Physics. [S0003-6951(98)00435-5].