14 / 2021-05-19 11:34:22

MODIFYING MECHANICAL AND OPTICAL PROPERTIES OF CELLULOSE NANOCRYSTAL FILMS USING LOW CONCENTRATION D-SORBITOL

cellulose nanocrystal film, D-sorbitol, hydrogen bonding, plasticization.

Cellulose nanocrystal (CNC) suspension can form liquid crystal film with their unique self-assembly behavior. The natural CNC film is fragile, which makes it difficult to be widely used. In this work, we propose a simple physical mixing method to obtain CNC film by adding D-sorbitol as plasticizer. We first find that the addition of D-sorbitol at low concentration can greatly improves the CNC film chemical properties, at the same time, the composite film do not show significant differences in the optical properties. The various low concentrations of D-sorbitol can be well dispersion in CNC aqueous suspension and the wavelength of the selectively reflected slight decreased 9 nm, for concentration from 0 to 6%. This phenomenon is opposite that the general reported that the wavelength of the selective reflected increases with the increase of plastic concentration. When the concentration of D-sorbitol was 4%, tensile strength, elongation at break, and Young modulus increase to 39.9 Mpa, 3.00%, and 2.99 GPa, respectively. The pitch of the chiral structure decreased from 406 to 362 nm with an increase in D-sorbitol concentration. This study shows that D-sorbitol as plasticizer can simply and effectively control the mechanical and retain the origin optical properties of CNC film.