Combination of Dynamic and Permanent Cross-Linking: A Pathway to Enhance Elasticity and Recyclability

Area of Science:

• Polymer Science
• Materials Science
• Chemical Engineering

Background:

• Thermosetting materials offer dimensional stability and elasticity but are not recyclable due to permanent cross-links.
• Recyclable materials often sacrifice mechanical properties like resilience.
• Developing elastomers with both high elasticity and reprocessability remains a significant challenge.

Purpose of the Study:

• To develop recyclable elastomers that combine the high elasticity of thermosets with the reprocessability of thermoplastics.
• To investigate the synergistic effect of combining reversible and irreversible cross-linked networks.
• To establish the relationship between elasticity and reprocessability by adjusting network proportions.

Main Methods:

• Incorporating both reversible and irreversible cross-linked networks into a polyurethane system.
• Constructing synergistic networks with distinct properties.
• Adjusting the proportion of synergistic networks to study material properties.

Main Results:

• Achieved simultaneous high elasticity and reprocessability in polyurethane elastomers.
• Demonstrated a synergistic effect between dynamic and chemical cross-linked networks.
• Established a clear relationship between elasticity and reprocessability based on network composition.

Conclusions:

• The developed synergistic network approach successfully combines high resilience and remolding ability in elastomers.
• This work provides a theoretical foundation for designing advanced recyclable elastomer materials.
• The findings pave the way for creating materials with the desirable attributes of both thermosets and thermoplastics.