Improvements in interlaminar strength: A carbon nanotube approach

Carbon nanotubes (CNTs), grown by chemical vapor deposition, improved the interlaminar strength of composites, as shown by a mode I double cantilever beam test. Failed specimens were inspected with a scanning electron microscope to determine the failure modes using fractography. The key findings indicated that exposure to high temperature must be limited to prevent fiber damage, and nanotubes longer than two times the fiber diameter reduce interlaminar strength, while high densities of short nanotubes improve interlaminar strength. Gains of up to 29.4% in glass, and 36.2% in IM7 are seen.