The polyynes are extremely unstable and reactive, and their long-term storage is still a challenge. We first used paraffin as an organic solvent in a submerged electric arc for preparing polyynes, placed them in solid paraffin at room temperature, and assessed their storage stability. One month late, we extracted the polyynes from paraffin, and separated the extracted polyynes by HPLC for obtaining single isolated polyynes. The polyynes extracted from solid paraffin were also purified and filled into open-ended single-walled carbon nanotubes (SWCNTs) to obtain polyynes@SWCNTs samples, which were heated to prepare single-walled carbon nanowires (SWCNWs, LLCCs@SWCNTs), made of long linear carbon chains (LLCCs) inserted inside SWCNTs. The 4L band at 7250 cm−1 was observed in the normal Raman spectra of SWCNWs for the first time. This work solves the problem of long-term storage of polyynes, and opened new avenues for exploring physical properties and applications of polyynes, LLCCs and SWCNWs.