A green large-scale fabrication of cellulose-based multifunctional fluorescent fibers for versatile applications

Luminescent fibers, particularly deriving from sustainable polymers, exhibit considerable potential for application in flexible smart materials. However, the large-scale preparation of fluorescent fibers has been hindered by the instability of physically doped fluorescent substrates or the complexity and cost of chemical modification. Herein, a scalable and green strategy for the fabrication of cellulose-based multifunctional fluorescent fibers is presented. Specifically, based on the clustering-triggered emission (CTE) mechanism, cellulose acetoacetate (CAA) fluorescent fibers are continuously synthesized for the first time through a lab-scale pilot wet-spinning machine. Subsequent derivatization processes are implemented to further improve the fluorescent properties of CAA fibers by promoting the radiation transition while suppressing nonradiative transition processes and impart additional functionalities to CAA fibers. The resulting fibers exhibit integrated performances with bright cyan-blue fluorescence emission (quantum yield of 36.07%), excellent UV-blocking (UPF being up to 72.04), hydrophobic (contact angle of 141.9 degrees), and effective antibacterial properties. Benefiting from their flexible and superior fluorescent performances, the resulting fibers have demonstrated potential applications in the fields of wearable fluorescent displays, information encryption, and fluorescent handicrafts. More interestingly, the multifunctional fluorescent fibers can be processed into clothes, showing promising application in multiple fields, such as multifunctional textiles, antibacterial dressing etc. This strategy not only provides a rational approach for the scalable production of one-dimensional (1D) multifunctional fluorescent material but also inspires the development of non-traditional sustainable fluorescent polymers.