Ultrastrong eutectogels engineered via integrated mechanical training in molecular and structural engineering.

Area of Science:

• Materials Science
• Polymer Chemistry
• Mechanical Engineering

Background:

• Ultrastrong gels typically exhibit high modulus and strength but suffer from limited stretchability due to hardening and embrittlement.
• Existing reinforcement methods often exacerbate these limitations, creating a dilemma between strength and ductility.

Purpose of the Study:

• To overcome the trade-off between strength and stretchability in ultrastrong gels.
• To develop a novel mechanical training strategy for enhanced gel performance.
• To engineer gels with exceptional mechanical properties through molecular and structural modifications.

Main Methods:

• Introduced deep eutectic solvent into polyvinyl alcohol hydrogels to induce hyperhysteresis via hydrogen bonding nanocrystals.
• Applied a single pre-stretching mechanical training to create hierarchical nanofibrils and prevent network structural recovery.
• Fabricated a chemically cross-linked second network to enhance overall stretchability.

Main Results:

• The engineered eutectogels demonstrated exceptional mechanical properties: fracture strength of 85.2 MPa, Young's modulus of 98 MPa, and work of rupture of 130.6 MJ m⁻³.
• These properties surpass those of previously reported gels, indicating a significant advancement.
• The hyperhysteresis-mediated training strategy proved effective in achieving both high strength and stretchability.

Conclusions:

• The developed hyperhysteresis-mediated mechanical training strategy successfully overcomes the inherent limitations of ultrastrong gels.
• The resulting eutectogels exhibit superior mechanical performance, offering a new class of advanced materials.
• This approach is generalizable to other solvents and polymers for creating ultrastrong organogels and inspires new fabrication technologies for self-reinforcing materials.