Resolving the Strength-Modulus-Elasticity Tradeoff in Elastomers Using Dual Phase-Separated Nanodomains.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Achieving elastomers with simultaneous ultrahigh strength, high modulus, and excellent elasticity is a significant challenge due to conflicting material properties.
• Conventional elastomers often face trade-offs, limiting their performance in high-stress applications.

Purpose of the Study:

• To develop a novel strategy for creating elastomers that overcome the intrinsic trade-offs between strength, modulus, and elasticity.
• To engineer materials with enhanced mechanical robustness and elastic recovery through a dual nanodomain approach.

Main Methods:

• Fabrication of elastomers via copolymerization of rigid aromatic polyurea segments and flexible poly(urethane-urea) chains with acylsemicarbazide moieties.
• Utilizing a dual phase-separated nanodomain strategy to create spatially confined reinforcing nanodomains.
• Characterization using small-angle X-ray scattering and electron microscopy to analyze nanodomain structures.

Main Results:

• The developed elastomers exhibit an exceptional combination of tensile strength (104.6 MPa), Young's modulus (43.1 MPa), and toughness (350 MJ m⁻³).
• Materials demonstrated full elastic recovery after 600% strain, attributed to synergistic reinforcement from two distinct nanodomains.
• Composites using these elastomers as binders for carbon-fiber fabrics achieved record-high fracture energies (up to 2059 kJ m⁻²).

Conclusions:

• The dual nanodomain strategy effectively resolves the strength-modulus-elasticity trade-off in elastomers.
• These high-performance elastomers offer superior mechanical properties, stability, healability, and reprocessability.
• The findings present a novel pathway for designing advanced elastomers for demanding applications, including high-performance composites.