Low Molecular Weight Polypyrmidine for Release and Size Controlled Process of Single-Walled Carbon Nanotubes

A process for controlling the size of Single-walled carbon nanotubes (SWCNTs) sorting was achieved by combining various centrifugation speeds with polypyrimidine's properties of dispersion and release SWCNTs upon acid treatment. At first, the SWCNTs wrapped by polypyrimidine were sperated into different size by centrifugating at various speeds. Then, these size-selected hybrids were treated with H₂SO₄ (98 %) to release free SWCNTs from hybrids, meanwhile the copolymer was collected for reuse. The purity of the released size-controlled SWCNTs was found to be higher than the commercial SWCNTs. The simple synthetic procedure of the copolymer, the low cost of H₂SO₄ and low centrifugation speed allow the process of size-controlled SWCNTs sorting to more practical applications and industrial scaling up.