Self-Healing 3D-Printed Polyurethane Nanocomposites Based on Graphene

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Polyurethane (PU) materials are widely used but often lack robust self-healing capabilities.
• Developing advanced PU nanocomposites with improved mechanical and regenerative properties is crucial for next-generation materials.

Purpose of the Study:

• To synthesize and characterize novel polyurethane nanocomposites incorporating ureido-pyrimidinone and graphene nanoparticles.
• To evaluate the thermal, mechanical, chemical, and self-healing properties of these new materials.
• To investigate the influence of graphene content and 3D printing on self-healing performance.

Main Methods:

• Two-step synthesis of polyurethane nanocomposites using polyol α,ω-dihydroxy[oligo(butylene-ethylene adipate)]diol.
• Incorporation of 1-3 wt.% graphene nanoparticles and ureido-pyrimidinone for enhanced hydrogen bonding.
• Characterization using mechanical testing, thermal analysis, and self-healing efficiency assessments.
• Evaluation of 3D printing processability and its impact on material regeneration.

Main Results:

• All synthesized nanocomposites exhibited high self-healing efficiencies ranging from 88-91%.
• The polyurethane containing 2 wt.% graphene showed the highest initial mechanical strength (~5 MPa), a significant improvement over pristine PU (~2 MPa).
• Complete healing of cuts was achieved within 1 hour at 80 °C, indicating fast recovery times.
• 3D printing did not negatively impact the self-healing properties, confirming material processability.

Conclusions:

• The developed polyurethane nanocomposites possess excellent self-healing capabilities and enhanced mechanical strength.
• The incorporation of graphene nanoparticles and the use of a novel polyol are effective strategies for improving PU performance.
• The material's processability via 3D printing opens avenues for diverse applications requiring complex geometries and autonomous repair.