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Load-bearing soft tissues normally show J-shaped stress–strain behaviors with high compliance at low strains yet high strength at high strains. They have high water content but are still tough and durable. By contrast, naturally derived hydrogels are weak and brittle. Although hydrogels prepared from synthetic polymers can be strong and tough, they do not have the desired bioactivity for emerging biomedical applications. Here, we present a thermomechanical approach to replicate the combinational properties of soft tissues in protein-based photocrosslinkable hydrogels. As a demonstration, we create a gelatin methacryloyl fiber hydrogel with soft tissue-like mechanical properties, such as low Young’s modulus (0.1 to 0.3 MPa), high strength (1.1 ± 0.2 MPa), high toughness (9,100 ± 2,200 J/m 3 ), and high fatigue resistance (2,300 ± 500 J/m 2 ). This hydrogel also resembles the biochemical and architectural properties of native extracellular matrix, which enables a fast formation of 3D interconnected cell meshwork inside hydrogels. The fiber architecture also regulates cellular mechanoresponse and supports cell remodeling inside hydrogels. The integration of tissue-like mechanical properties and bioactivity is highly desirable for the next-generation biomaterials and could advance emerging fields such as tissue engineering and regenerative medicine.
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This content will become publicly available on March 28, 2026
Carbonization of Butadiene Enables Recyclable Carbon Fiber Polymer Composites
The catalytic conversion of carbon dioxide into polymers via high-energy comonomers offers a sustainable, low-cost, and low-emission approach for developing conveniently manufactured high-performance materials without competing for land-use or food resources. We present the synthesis of poly(amidoamine) polymers stoichiometrically derived from carbon dioxide, butadiene, and amines displaying useful mechanical properties (tensile strength 43 MPa, Young’s modulus 840 MPa, and flexural modulus 2.8 GPa). The low viscosity precursors are applicable to producing carbon fiber reinforced polymers with fiber wetting and rapid network formation (16 minutes at 150°C). This work reveals that internal hydrogen-bonding catalyzes the ring-opening polymerization, and the intramolecular alcohol moiety promotes chemical recyclability in acidic conditions, allowing fiber recovery with <1.0 wt % difference from virgin fiber and monomer in 72% yield.
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- Award ID(s):
- 2215940
- PAR ID:
- 10652205
- Publisher / Repository:
- Engage
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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