Self-Healable, Solvent Response Cellulose Nanocrystal/Waterborne Polyurethane Nanocomposites with Encryption...

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Cellulose nanocrystal (CNC)-based chiral nematic structures are vital for stimulus-responsive and sensing applications.
• Enhancing mechanical properties and environmental adaptability of chiral nematic materials is a key research focus.

Purpose of the Study:

• To develop a flexible photonic film with self-healing capabilities.
• To investigate the mechanical robustness, self-healing efficiency, and environmental responsiveness of the developed film.

Main Methods:

• Preparation of a flexible photonic film with self-healing ability (FPFS) by combining waterborne polyurethane with dynamic covalent disulfide bonds (SSWPU) and CNC.
• Evaluation of mechanical properties under various stresses (stretching, bending, twisting, folding).
• Assessment of self-healing efficiency at room temperature and response to common solvents.

Main Results:

• The FPFS exhibited excellent toughness and mechanical resilience.
• The film demonstrated efficient self-healing within 2 hours at room temperature.
• Reversible color changes were observed upon exposure to typical solvents.
• Visible patterns were formed on the FPFS using ethanol as ink, observable under polarized light.

Conclusions:

• The developed FPFS offers a promising platform for self-healing, solvent-responsive, and flexible photonic materials.
• The material has potential applications in biological anti-counterfeiting and advanced sensing technologies.