Stretchable Laminates with Tunable Structural Colors from Layered Stacks of Elastomeric, Ionic, and Natural Polymers

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Cellulose nanocrystals (CNCs) exhibit color iridescence due to helical structures but lack stretchability.
• The brittle nature of CNCs limits their application in flexible materials.

Purpose of the Study:

• To create highly stretchable composite materials incorporating CNCs.
• To maintain the structural color properties of CNCs in a flexible format.
• To explore applications in wearable sensors and photonic devices.

Main Methods:

• Fabrication of layered elastomeric composites using CNCs and branched ionic polymers (bIPs).
• Incorporation of amine-terminated poly(N-isopropylacrylamide) (PNIPAM) within the composite structure.
• Mechanical testing to evaluate stretchability and toughness.

Main Results:

• The composite materials achieved high mechanical stretchability up to 150% strain.
• Composite toughness significantly increased due to crack arresting mechanisms.
• Preservation of vivid structural colors from CNCs, responsive to humidity and temperature.

Conclusions:

• Developed stretchable, tough, and color-tunable composite materials using CNCs and bIPs.
• These materials retain structural color and mechanical integrity under strain.
• Promising candidates for robust wearable sensors, flexible optical labels, and photonic devices.