Multiple H-bonds induced mechanically robust vat photopolymerization 3D printing poly(urethane-urea) elastomers

Area of Science:

• Materials Science
• Polymer Chemistry
• Additive Manufacturing

Background:

• Vat photopolymerization (VP) elastomers struggle with mechanical strength and durability due to incomplete polymerization and weak layer adhesion.
• Existing VP elastomers often lack the required mechanical robustness for demanding applications.

Purpose of the Study:

• To develop high-performance poly(urethane-urea) elastomers (PUEs) for VP 3D printing.
• To enhance mechanical properties, including strength, elasticity, and durability, through a dual cross-linked network (DCN) strategy.

Main Methods:

• Incorporation of multiple hydrogen-bonded urethane and urea groups into PUEs.
• Utilizing a DCN strategy combining hydrogen bonding and covalent cross-linking.
• Fabrication of 3D-printed structures using VP.

Main Results:

• Achieved a tensile strength of 28.30 ± 1.10 MPa.
• Demonstrated a recovery strain of approximately 300% and fracture energy of 22.90 ± 4.20 kJ m^-2.
• Successfully fabricated 3D-printed stents with intricate architectures, high load-bearing capacity, and excellent biocompatibility.

Conclusions:

• The DCN strategy significantly improves the mechanical properties and interfacial bonding of VP elastomers.
• The developed PUEs are suitable for rapid fabrication of complex, mechanically robust structures.
• This approach broadens the application scope of PUEs in engineering and biomedical fields.