Macroscopically Aligned Graphite Films Prepared from Iodine-Doped Stretchable Polyacetylene Films Using...

Area of Science:

• Materials Science
• Polymer Chemistry
• Solid State Physics

Background:

• Polyacetylene (PA) films are versatile precursors for carbon materials.
• Morphology-retaining carbonization is a key technique for preserving precursor structure.
• Achieving high mechanical and electrical properties in graphite films is a significant challenge.

Purpose of the Study:

• To develop graphite films with superior mechanical and electrical properties.
• To investigate the effect of precursor alignment on graphite film characteristics.
• To establish an efficient and high-yield production method for graphite films.

Main Methods:

• Preparation of typical and stretchable polyacetylene (PA) films.
• Morphology-retaining carbonization of iodine-doped PA films at 800 °C.
• Graphitization of carbon films at high temperatures (1400-3000 °C).
• Mechanical stretching of PA films to induce macroscopic alignment.
• Evaluation of material properties using polarized infrared absorption spectra and X-ray diffraction (XRD).

Main Results:

• Graphite films retained the surface morphology of the PA precursors.
• Typical PA-derived graphite films showed tensile strengths up to 224 MPa and conductivity of 2.5 × 10(2) S/cm.
• Aligned graphite films exhibited enhanced conductivity up to 1.5 × 10(3) S/cm along the stretching direction.
• High total yield of graphite films (61-74%) was achieved at temperatures up to 3000 °C.

Conclusions:

• Iodine-doped PA films are efficient carbon sources for high-performance graphite films.
• Mechanical stretching of PA precursors enables the production of anisotropic graphite films with improved conductivity.
• The developed method offers a high-yield and cost-effective route to advanced graphite materials.