writer：Xinkai Li, Xiaoyan Qiu, Xin Yang, Peng Zhou, Quanquan Guo, and Xinxing Zhang*
keywords：birefringence, cellulosic materials, dynamic covalent network, multi- modal melt-processing, programmable anti-counterfeiting, recyclability
source：期刊
Issue time：2024年

Ubiquitous anti-counterfeiting materials with a rapidly rising annual

consumption (over 1010 m2)can pose a serious environmental burden.

Biobased cellulosic materials with birefringence o?er attractive sustainable

alternatives, but their scalable solvent-free processing remain challenging.

Here, a dynamic chemical modi?cation strategy is proposed for multi-modal

melt-processing of birefringent cellulosic materials for eco-friendly

anti-counterfeiting. Relying on the thermal-activated dynamic covalent-locking

of the spatial topological structure of preferred oriented cellulose, the strategy

balances the contradiction between the strong con?nement of long-range

ordered structures and the molecular motility required for entropically-driven

reconstruction. Equipped with customizable processing forms including

mold-pressing, spinning, direct-ink-writing, and blade-coating, the materials

exhibit a wide color gamut, self-healing e?ciency (94.5%), recyclability, and

biodegradability. Moreover, the diversi?ed ?exible elements facilitate scalable

fabrication and compatibility with universal processing techniques, thereby

enabling versatile and programmable anti-counterfeiting. The strategy is

expected to provide references for multi-modal melt-processing of cellulose

and promote sustainable innovation in the anti-counterfeiting industry.