Investigation of the effects of environmentally friendly degumming methods on silk dyeing performance

Abstract

In this paper, firstly the effects of environmentally friendly degumming methods on the morphology and structure of fibers have been investigated. Then the dyeing behaviors of environmentally friendly degummed silk fibers were analyzed. In the dyeing process, acid and reactive dyes were used at various dye concentrations. To analyze dyeing characteristics of these fibers, investigations of washing fastness and measurements of color parameters were carried out. Scanning electron microscopy (SEM) images of degummed silk fibers showed that the high temperature (HT) degumming method was more successful than the other methods, but the results were comparable. Weight loss values were also supported by SEM images. Scanning electron microscopy with energy-dispersive X-ray analysis of degummed fibers showed that particles remaining on the surface were the most likely to indicate sericin residue. Fourier transform infrared spectra of raw and degummed fibers with different methods demonstrated typical absorption bands appointed to the peptide bonds (-CONH-) and no major differences were observed. When band intensity was examined, the most intense bands belong to the HT degumming process. The differential scanning calorimetry curves of conventionally and alternatively degummed silk fibers showed two endotherms at around 100℃ and 320℃ because of water loss and β-sheet fibroin decomposition, respectively. The acid and reactive dyeing of the degummed fibers by environmentally degumming methods gave similar color strength and washing fastness values compared with conventionally degummed fibers.

Extraction of Silk Fibroin with Several Sericin Removal Processes and its Importance in Tissue Engineering: A Review

“…The dyeing treatment was performed with several acid concentration and reactive dyes and was scrutinized based on K/S, ΔE*, and washing fastness values. The experimental results suggest that the grade of the dyeing process was imminent to the traditional treatment processes [13].…”

“…The amount of sericin extracted from the silk thread after degumming with 2 g/L bromelains at 55 °C and 90 min was 96.58 ± 2.58%. With increasing the High temperature and high pressure Free of chemicals with lowering of cost incurred in recycling process Damages of fibroin with toxic gas emissions [13] Microwave irradiation Eco-friendly approach and overall energy conservation can be attainable Damage to silk fibroin and commercially viability is limited [43] Infrared (IR) heating A green method with avoiding of multi step method…”

“…Sericin is the most remarkable crude ingredient for different industries like cosmetics, garments, foods, biomaterials, and biomedicines due to its antibacterial, anti-cancer, moisturizing, and ultraviolet (UV) resistant characteristics. Hence, it has a great significance to restore the protein molecule from the silk effluent after the degumming process [13]. Some non-fiber crude cocoon extract contains protease inhibitors (CSTIs) in the layer of sericin, which belongs to the Kunitz-type family.…”

Recent Advances in Environmentally Friendly and Green Degumming Processes of Silk for Textile and Non-Textile Applications

“…Apart from the above teams devoted to studying the biological degumming of silk filaments with enzymes, other groups also promote this art [17][18][19][20][21][22][23][24][25][26][27]. It is anticipated that with the discovery, screen and isolation of more enzymes suitable for the silk degumming, corresponding environmentally friendly and green degumming processes will be developed and make silk degumming flourish.…”

“…In the traditional textile industry, the degummed silk filaments are usually used for further wet process, such as dyeing, printing and finishing. Therefore, the effect of degumming process on wet process of silk filament is an interesting and meaningful topic [17,18,22,24,25,32,33,48].…”