Preparation and Characterization of Cellulose Nanocrystal-Doped Cellulose Triacetate Optical Films by Sol-Gel Process

A bio-based nanocomposite optical film was obtained through a simple sol-gel process and solution casting. The dispersion effect of cellulose nanocrystals (CNCs) gel and the optical properties, mechanical performance and thermal stability of CNC-doped cellulose triacetate (TAC) films (TAC-X) were systematically evaluated. The results show that CNCs can be well dispersed in hydrophobic organic solvents and TAC matrices through the sol-gel process. TAC-X film has excellent optical properties, its light transmittance is above 92 %, its haze value and birefringence are low, ranging from 0.21 +/- 0.01 % to 0.38 +/- 0.02 %, and (1.64 +/- 0.26)x10-6 to (2.49 +/- 0.50)x10-6 respectively. When doped with 2 wt % CNCs, the tensile strength and Young's modulus of the TAC-2 film were 33.0 % and 30.1 % higher than those of the pure TAC film, separately. At the same time, the TAC-X film also maintains good thermal stability, with its glass transition temperature and maximum decomposition temperature falling between 215-216 degrees C and 366-368 degrees C respectively. The simple sol-gel process provides a convenient and efficient way to use CNCs doping to enhance the physical and mechanical properties of TAC optical films. Cellulose nanocrystals (CNCs) doped triacetate cellulose (TAC) optical films are prepared by a simple sol-gel process and solution casting method. This provides a solution to the dispersibility and compatibility issues in the preparation of CNC nanocomposites. The prepared TAC nanocomposite films have excellent optical properties and enhanced mechanical properties, and maintain good thermal stability. image