Biocompatible Poly(urethane-urea) Elastomers with High Toughness and Elastic Restorability.

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Biocompatible elastomers are crucial for biomedical applications, requiring a combination of high toughness and elastic restorability.
• Simultaneously achieving both high toughness and excellent elasticity in a single material presents a significant scientific challenge.
• Existing materials often compromise one property for the other, limiting their potential in demanding biomedical fields.

Purpose of the Study:

• To synthesize and characterize novel polycaprolactone-based poly(urethane-urea) (PUU) elastomers.
• To achieve a synergistic combination of high toughness, superior elastic restorability, and biocompatibility in a single elastomer.
• To explore the structure-property relationships governing the mechanical and biocompatibility performance of these PUU elastomers.

Main Methods:

• Utilized hydrazide chain extenders to introduce extensive hydrogen bonding for enhanced toughness.
• Employed isophorone diisocyanate with a bulky structure to control hard segment aggregation and suppress strain-induced crystallization.
• Evaluated mechanical properties including toughness, strength, and elastic recovery at various strain levels.
• Assessed material characteristics such as healability, recyclability, and in vitro biocompatibility.

Main Results:

• The developed PUU elastomer exhibited remarkable toughness (333.2 MJ m⁻³) and strength (63.7 MPa).
• Achieved excellent elastic recovery with low residual strains of approximately 11% at 100% strain and 44% at 400% strain.
• Demonstrated significant healability, recyclability, and good biocompatibility, confirming its suitability for biomedical applications.

Conclusions:

• The synthesized polycaprolactone-based PUU elastomers successfully combine high toughness with excellent elastic restorability and biocompatibility.
• The strategic use of hydrazide chain extenders and isophorone diisocyanate is effective in tailoring material properties.
• These advanced elastomers represent a promising candidate for various biomedical applications, offering valuable insights for future material design.