Cheap, high yield, and strong corn husk-based textile bio-fibers with low carbon footprint via green alkali retting-splicing-twisting strategy

Natural corn husk (NCH) from Zea mays L., which contains 46% cellulose, is an ideal resource for the production of corn husk-based textile bio-fibers (CHTFs). Conventional techniques, using a combination of chemical and enzymatic extraction, produce only low yields (∼15%) because most of the hemicellulose/lignin and short fibers are removed. The fibers produced also have low strength because of their inherently porous structure. Here, CHTFs were prepared in high yield (73%), using a room temperature alkali retting-splicing-twisting strategy that retains more of the hemicellulose/lignin. Using this strategy, 14.6 million tons of CHTF could be produced annually in China. Because of the dense yet aligned structure of the lignocellulose fibers, the tensile strength of the CHTFs (139 MPa) is 12-fold higher than that of raw material (i.e. corn husk) and even 30% higher than that of wood-based textile fibers. Super-long CHTFs can be obtained, without the use of additional glue, by overlapped edge-pressing of several retted corn husks. The production cost and carbon footprint of are low ($0.5·kg−1 and 0.74 kg CO2e/kg, respectively), since the only consumables are NCH, NaOH and water. This work exemplifies a green and sustainable technology for producing non-cotton, glue-free, high yield, cheap and strong bio-textile fibers from agricultural waste, and contributes to carbon neutralization by reducing greenhouse gas emissions.