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The so-called woolification of jute involves treating jute yarns with 15%-18% caustic soda for 30-60 minutes in a relaxed state at room temperature. When jute fibers are treated with a high concentration of alkali, their physical structure undergoes significant changes; lateral swelling and longitudinal contraction occur simultaneously. As a result, the fibers become softer to the touch and develop a high degree of curling, giving them a wool-like appearance. This wooling effect increases with higher alkali concentration and lower treatment temperature. It is completely different from the cotton mercerizing process, as follows: (1) Processing method: The woolification process involves treating jute with (15%–18%) caustic soda at room temperature for 30–60 minutes ； The mercerization process involves treating cotton yarn or fabric with 22%–25% caustic soda at room temperature under tension for 1–2 minutes. (2) Before washing: In the former case, before washing (relaxation treatment), the jute fibers are not stretched after being immersed in caustic soda ； The latter yarns or fabrics are stretched to their original size before washing (i.e., tension treatment). (3) Results: After lanolinization, jute fibers became curled ； Cotton yarns or fabrics are mercerized to achieve dimensional stability. (4) Weight loss: 15% weight loss of the fibers due to wooling ； After mercerization, the weight of the yarn or fabric decreases by about 3%. (5) Impact on performance: Wooling improves the fineness of jute fibers, giving them better spinability and a better fabric appearance ； Mercerization improves the luster and dyeability of yarns or fabrics. (6) Strength loss: The strength loss of jute fibers is approximately 25%–40% ； The strength loss of cotton is about 10%–15%. (7) Elastibility: The elongation degree of jute fibers has increased ； The elongation at break of cotton decreased slightly. (8) Persistence of surface modification: Woolen jute has poor curl stability; once the fibers are stretched, the curls disappear immediately ； The improvement in the luster and dyeability of mercerized cotton is permanent. (9) Color change: Color change of jute fibers after woolification ； After mercerization, the cotton shows no change in color. (10) Processing method: Wool is processed in batches, while fabric mercerization is a continuous process. (11) Alkali consumption: Jute has a high alkali absorption capacity, resulting in high alkali consumption ； In contrast, cotton mercerization requires less alkali. (12) Recovery: In the former case, due to the high impurity content, it is difficult to recover the alkali from the wash liquid ； The latter can recover about 95% of caustic soda from the wash liquor. (13) Importance: The former is more technically important, but it requires more labor and costs ； The latter is important both technically and commercially.