Rational design of stable fluorescent and hydrophobic cellulose-based film for full-band UV-blocking

A novel fluorescent, hydrophobic cellulose-based UV-blocking film was developed via chemical modification. Cellulose acetoacetate film was firstly regenerated by acetyl acetylation of cellulose in a homogeneous system. Based on this esterified film, both 1,4-dihydropyridine fluorescent rings and hydrophobic octadecylamine were bonded to cellulose chains through Hantzsch reaction and the formation of enamine bonds, by using a one-pot process under room temperature. The resulting film exhibited bright fluorescence and excellent UV-blocking properties (shielding almost 100% UV), which were very stable even after exposing to long periods of UV radiation, harsh temperature treatment and different solvents. In addition, this film had good hydrophobicity (the contact angle reached up to 112 degrees). This work provided a facile and environmentally friendly strategy to fabricate multifunctional cellulose-based film, which have great application potential in the field of UV protection, fluorescent materials, packaging, and covering materials for greenhouses. [GRAPHICS] .