Cleaner Engineering and Technology (Oct 2021)
Functionalizing cotton fabrics through herbally synthesized nanosilver
Abstract
The ultraviolet (UV) radiation is increasing in atmosphere due to the continuous increasing of global warming throughout the globe, which causes a negative impact on the human skin. The aim of this work is to produce an ecofriendly fabric having functional properties of UV protection & antimicrobial using herbal synthesized colloidal solution of silver nanoparticles (H-AgNPs). This solution was synthesized with Tulsi (Ocimum tenuiflorum) extract as a reducing and capping agent. The cotton woven sample was developed with ten layers of colloidal solution of H-AgNPs using anionic surfactant sodium dodecyl sulfate (SDS) through pad-dry-cure method. Besides, another sample developed with the mixture of natural oils and the same concentration of H-AgNPs colloidal solution. Treated samples were subjected to color strength (K/S value) measurement, color fastness test, scanning electron microscopy (SEM) analysis, ultra-violet protection factor (UPF) test and antimicrobial test for evaluating their different functional & aesthetic performances. Testing data reveals that the treated sample has higher color strength of 0.95 compared to the untreated 0.04 and excellent all-round color fastness ratings of 4–5 for wash, 6–7 for light, 4 for dry rubbing & 3–4 for wet rubbing in contrast to the untreated one. SEM analysis confirmed that the H-AgNPs successfully deposited on cotton fibre surface. X-ray diffraction (XRD) experiment revealed the mean crystal size of H-AgNPs about 23 ± 3 nm. On the other hand, tensile strength increased by 6N & elongation 3–4% in both warp and weft direction. Moreover, less UV transmission of 1.04% & 3.12% for UV-B and UV-A respectively represents outstanding UV protection. In addition, antimicrobial test depicts the zone of inhibition for gram-positive S.aureus 9.5± 0.5 mm & gram-negative E.coli 10.5± 0.9 mm, respectively. The presence of phytochemicals of Tulsi extract, natural oils, and chemical compounds of cellulosic cotton has been further analyzed by Fourier transform infrared spectroscopy (FTIR) spectrum investigation.