Cellulosic fibers with high aspect ratio from cornhusks via controlled swelling and alkaline penetration

Cellulosic fibers with high aspect ratio have been firstly obtained from cornhusks via controlled swelling in organic solvent and simultaneous tetramethylammonium hydroxide (TMAOH) post treatment within restricted depth. Cornhusks, with around 42% cellulose content, are a copious and inexpensive source for natural fibers. However, cornhusk fibers at 20 tex obtained via small-molecule alkaline extraction were too coarse for textile applications. Continuous NaOH treatment would result in fine fibers but with length of about 0.5-1.5 mm, too short for textile use. In this research, post treatment using TMAOH and under controlled swelling significantly reduced fineness of cornhusk fibers from 21.3 ± 2.88 to 5.72 ± 0.21 tex. Fiber length was reduced from 105.47 ± 10.03 to 47.2 ± 27.4 mm. The cornhusk fibers had more oriented microstructures and cellulose content increased to 84.47%. Besides, cornhusk fibers had similar tenacity, longer elongation, and lower modulus compared to cotton and linen, which endowed them with durability and flexibility.