Akademik Veri Yönetim Sistemi
2nd International Congress on Wool and Luxury Fibres-ICONWOOLF 2022, Tekirdağ, Türkiye, 20 Mayıs 2022, ss.63-70
In this research, the effect of various proteolytic enzymatic pretreatment on morphological and
chemical features, and dyeability properties of wool fibers were investigated. Scoured merino
wool fibers are treated with protease, papain, trypsin, and pepsin in specified conditions. Each
enzyme activity measurement was provided by appropriate methods such as Bradford, BAPNA,
and BSA spectroscopy. The enzyme solutions were prepared at a concentration of 1 mg/mL.
Enzymatic processes were carried out for 24h in the incubator set at 40 °C, 100 rpm stirring
speed at the temperature and specified pH. Whiteness index (Stensby) and yellowness index
(ASTM D 1925) were examined after enzymatic pretreatment. Trypsin treated wool fibers
showed the highest whiteness index (59.6) while untreated wool fibers have 52.2. FT-IR was
employed for the investigation of chemical changes. The increase in intensity of amide-related
bands and hydroxyl bands after enzymatic treatment was observed. SEM photomicrographs
revealed the cuticle layer is partially removed in enzyme-treated fibers. Elemental identification
was provided by SEM-EDX. It appears that the sulfur bonds are decreased after the treatment
and the pepsin-treated fibers have fewer bonds of all. In order to examine the damage to the
structure, photomicrographs were taken using fluorescence and light microscope. The alkali
solubility test (ASTM D1283) was also conducted to compare different enzyme types. Wool
fibers were dyed in 2.0% concentration with reactive dyestuff. Dyeability (K/S) and
colorimetric features of fibers were measured by a Minolta CM 3600d spectrophotometer. The
washing fastness test showed that all the samples have good results and the color change after
washing was negligible in enzyme-treated samples (grade 5) compared to untreated wool fibers
(grade 4-5).