Cotton dyeing performance enhancing mechanism of mangiferin enriched bio-waste by transition metals chelation
M. Tauhidul Islam, Md Luthfar Rahman Liman, Manindra Nath Roy, Md. Milon Hossain, Md. Reazuddin Repon, Md. Abdullah Al Mamun
Abstract
This study reported a sustainable and facile coloration approach of cotton fabric by exploiting mangiferin enriched mango seed kernel bio-waste. The extract principally contains mangiferin and different polyphenolic chromophores such as hydrolysable tannin, flavonoids (quercetin), betacyanin and saponin which were confirmed by phytochemical screening. The optimum conditions for dyeing were found at 90 °C with a time interval of 60 min and the overall fixation rate of chromophores was ranging from 56 to 71%. Different transition metals (Fe2+, Cu2+, Al3+, and Sn2+) were utilized to promote the fixation of mangiferin enriched dye (MED) chromophores. The higher absorption mechanisms of MED chromophores have been discussed in terms of molecular orientation (TCI, LOI), and inter and intra-molecular hydrogen bonding configuration (HBI, EH, R). The total amount of anchored chromophores was expressed by the asymmetric factor (AF). The maximum dye-fiber bonding behavior was proposed in Fe2+ encased sample with an improvement of color strength (K/S) from 5.97 to 7.20. Besides, the addition of electrolytes in the dye bath further improved the chromophores' exhaustion (K/S = 8.4). Higher chromophores fixation with metallic cross-linkers and cationic electrolyte endowed diverse colorimetric values (L*, a*, b*, c*, h, BI, ΔE) for the dyed samples and ensured excellent colorfastness properties in comparison to other natural dyeing processes.