Palmitoylated cellulose nanocrystal/polycarbonate composite with high mechanical performance and good transparency.

To fabricate polycarbonate (PC) composites with high mechanical and optical properties, PC composite films reinforced by cellulose nanocrystals esterified using palmitoyl chloride (palmitoylated cellulose nanocrystal [PAL‐CNCs]) were fabricated by casting‐evaporation and characterized by several techniques. It was shown that the PAL‐CNCs with a substitution degree of 0.43 and the crystalline index of 53.3% were better dispersed in chloroform and tetrahydrofuran, and achieved a water contact angle of 81.0°. The crystallite size and crystalline index of the PC in the composite film significantly increased to more than 5.2 nm and 51.5%, respectively, after the incorporation of the PAL‐CNCs. The PC composite film had an increase of 91.4% in tensile strength, 84.1% in Young's modulus, and a decrease of 5% in impact strength. Meanwhile, its UV–Vis‐light transmittance was above 90%. Therefore, the palmitoylated ‐CNCs were a better candidate for engineering PC composites with high mechanical performance and transparency. [ABSTRACT FROM AUTHOR]