Functional electrospun polylactic acid core-shell thermochromic fibers with modified cellulose nanocrystals for enhanced temperature-responsive applications

Core-shell electrospun fibers with thermochromic materials are suitable for temperature sensing due to their customizable properties. However, the beneficial effect of bio-based thermochromic fibers incorporating sustainable nanomaterials needs to be further demonstrated, especially regarding their thermal stability and mechanical properties. In this study, core-shell structured nanofibers were produced through a co-axial electrospinning process using polylactic acid (PLA) and surface-modified cellulose nanocrystals (mCNCs) as the shell, and crystal violet lactone (CVL), bisphenol A, and 1-dodecanol as the core. Chemical characterization confirmed the successful grafting of vinyl siloxane within mCNCs, enhancing CNC dispersion in the PLA matrix. The thermochromic fibers exhibited smooth, uniform surfaces, with minimal impact of mCNCs on the glass transition temperature (T-g). Compared with neat electrospun PLA fibers, mCNC-added fibers showed improved thermal stability. Although the core material negatively affected mechanical properties, mCNCs enhanced tensile strength and Young's modulus. The fibers demonstrated rapid and sensitive responses to temperature changes from 0 to 20 degrees C, indicating their potential as effective temperature sensors with improved properties.