A green route to covalently-fluorescent whitening cotton fabric for excellent washing durability and skin safety via electron beam irradiation

Herein, a new method was developed for efficient and lasting fluorescent whitening cotton fabric by synthesizing and using a vinyl-containing fluorescent whitening agent to covalently grafting onto fiber surfaces with the assistance of electron beam irradiation. The results from FT-IR spectroscopic, X-ray photoelectron spectroscopic, and energy dispersive spectrometric analyses showed that the fluorescent whitening agent was successfully anchored on cotton fiber via radiation-induced grafting copolymerization. The optimized whiteness value at 110.81 (that of raw cotton fabric, 74.50) was achieved using just 0.3-wt% fluorescent whitening agent. Notably, the whiteness value of the treated cotton fabric remained 110+ even after 100 equivalent home-washing cycles, substantiating its excellent washing durability. Skin stimulation experiments on rabbits showed that the primary stimulation index of all experimental groups was 0 and no abnormal clinical symptoms were found in all tested rabbits, demonstrating the outstanding skin safety. Furthermore, energy generated by irradiation grafting technology was much lower than that of traditional processes and water consumption greatly reduced. Even the effluent from this process completely met the discharge standard of industrial wastewater without any treatment. This study explores a new method for textile finishing via electron beam irradiation, providing a green and sustainable perspective for the textile industry.