15 / 2021-05-20 14:30:54

Chiral cellulose nanocrystal humidity-responsive photonics film with glucan for tuned iridescence and reinforced mechanics

Cellulose nanocrystal, Structural color, Glucan composite mechanics, Humidity-responsive

The fabrication of biomimetic photonic composite materials with environmental stimuli-responsive functions from entirely biobased materials are becoming increasingly challenging with the growing demand for biodegradable materials, which attribute to photonics composite materials possesses conspicuous merits including brilliant and controlled structural color, environmental friendliness and sustainability. Different from the traditional composite film with biopolymer as the main material and CNC as the reinforcing material. In this study, we prepared a wholly biobased chiral nematic CNC composite film with CNC as the main component and biopolymers as the reinforcing material. Effect of glucan with different molecular weights on mechanical performance and tunable structural color of iridescent CNC composite films was investigated. The existence of glucan does not influence the self-assembly performance of CNC but rather leads to the improvement of mechanical performance, making it possible to obtain free-standing iridescent CNC films with tunable structural colors. In response to environmental humidity, iridescent composite films can change structural colors via regulating their chiral nematic structures. The resulting biobased composite film has potential applications in decorative coating, optical and humidity sensing and anti-counterfeiting fields.