Effects of alkali and ultraviolet treatment on colour strength and mechanical properties of jute yarn

In this study, jute yarns were treated with an aqueous alkali solution and ultraviolet light to improve dyeability. Ultraviolet light treatments were carried out at an air pressure of 1 atm, under water and vacuum, and all the samples were dyed with reactive dyes. Virgin samples and treated jute yarns were analysed by Fourier Transform–infrared spectroscopy. K/S values were determined by a reflective spectrophotometer and used to establish the fixation values and colour strength of the dyed samples. The tensile mechanical properties of the samples were also measured by a tensile testing apparatus and were compared with the virgin samples. Alkali treatment resulted in a reduction in carbonyl group concentration. However, atmospheric ultraviolet light treatment increased carbonyl group concentration. Dyeability and dye fixation values for atmospheric and underwater ultraviolet light‐treated samples increased. Furthermore, the loss of tensile strength for alkali‐treated samples was much greater than others (up to 50%) in comparison with ultraviolet light‐treated samples.