Team incorporates stretched CNTs into carbon composites

Researchers from North Carolina State University (NCSU) say they have developed new methods for stretching carbon nanotubes (CNTs) and using them to create carbon composites.

By stretching the CNT material before incorporating it into a composite for use in finished products, the researchers straighten the CNTs in the material, which significantly improves its tensile strength and enhances the stiffness of the composite material and its electrical and thermal conductivity.

Researchers used a rotating spool to create ribbon-like composite materials that have a high percentage of carbon nanotubes, for use in products ranging from aircraft to bicycles.

Carbon-fibre composites are currently used to build aircraft and other products where strong, lightweight materials are desirable. However, researchers have long thought that if these composites could be made with CNTs they could be as strong, but 10 times lighter.

According to NCSU, creating a strong CNT composite requires four features: first it needs long CNTs, which are more effective at carrying loads; then, the CNTs need to be aligned in rows; third, the CNTs in the material are held together by a polymer or resin and there must be a high ratio of CNTs to polymer in the finished composite material; and finally, CNTs need to be as straight as possible so that the material bears weight evenly.