Biodegradable Dual-Network Chitosan Composite Aerogel by In Situ Mineralization for Substituting Petroleum-Based...

Area of Science:

• Materials Science
• Polymer Science
• Green Chemistry

Background:

• Chitosan aerogels are promising bio-based materials but have limitations in flammability, thermal insulation, and resilience.
• Existing methods struggle to simultaneously enhance multiple properties of chitosan aerogels.

Purpose of the Study:

• To develop a high-performance chitosan composite aerogel with improved thermal insulation, fire resistance, and mechanical properties.
• To achieve synergistic enhancement of multiple properties through a novel dual-network structural strategy.

Main Methods:

• Fabrication of a chitosan composite aerogel via in situ mineralization of a phosphorus, nitrogen-containing organosilica network within a chitosan matrix.
• Utilizing hydrolytic polycondensation for network formation.
• Characterization of thermal conductivity, limiting oxygen index, reversible compressible resilience, and biodegradability.

Main Results:

• The composite aerogel exhibited ultralow thermal conductivity (22.4 mW·m⁻¹·K⁻¹).
• Achieved a high limiting oxygen index (38.1%) indicating good fire resistance.
• Demonstrated good reversible compressible resilience and complete soil biodegradation within 15 days.
• Retained over 85% of initial performance after 20 recycling cycles due to dual-network hydrogen bonding.

Conclusions:

• A dual-network structural strategy successfully created a high-performance chitosan composite aerogel.
• The developed aerogel offers a sustainable alternative to petroleum-based insulation materials.
• This approach contributes to achieving carbon neutrality goals through advanced bio-based materials.