Strong, Shape-Memory Lignocellulosic Aerogel via Wood Cell Wall Nanoscale Reassembly

Area of Science:

• Materials Science
• Polymer Science
• Biomaterials Engineering

Background:

• Polymer shape-memory aerogels (PSMAs) show promise in aerospace and biomedicine but are challenging to fabricate with good mechanical properties, often relying on fossil-based polymers.
• Developing sustainable and high-performance PSMAs is crucial for advanced applications like thermal insulation, actuators, and sensors.

Purpose of the Study:

• To develop a sustainable method for fabricating strong, shape-memory bio-aerogels from native wood.
• To investigate the nanoscale structural rearrangement and properties of wood-derived aerogels.

Main Methods:

• One-step treatment of native wood using an ionic liquid mixture ([MTBD]+[MMP]-/DMSO).
• Characterization using confocal Raman spectroscopy, Atomic Force Microscopy (AFM), Small-Angle X-ray Scattering/Wide-Angle X-ray Scattering (SAXS/WAXS), Nuclear Magnetic Resonance (NMR), and digital image correlation.

Main Results:

• Fabrication of strong, shape-memory bio-aerogels with high specific surface areas (up to 220 m²/g) and low thermal conductivity (0.042 W/mK).
• Achieved nanoscale spatial rearrangement of wood biopolymers, enabling flexible hydrogels and intricate aerogel geometries.
• Demonstrated shape-memory function triggered by water stimulus.

Conclusions:

• The developed methodology offers a simple, sustainable, and advanced approach for designing bio-based shape-memory aerogels.
• Wood-derived aerogels exhibit excellent properties suitable for diverse applications, advancing the field of sustainable materials.