Frontal Polymerization-Enabled 3D Printing of Recyclable High-Performance Carbon Fiber Reinforced Polymers

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Manufacturing

Background:

• Thermoset composites present a trade-off between performance and recyclability.
• Traditional manufacturing methods are energy-intensive and generate significant waste.

Purpose of the Study:

• To develop a closed-loop manufacturing approach for fully recyclable carbon fiber-reinforced polymers (c-CFRPs).
• To integrate frontal ring-opening metathesis polymerization (FROMP) with 3D printing for efficient composite production.

Main Methods:

• Developed a self-propagating FROMP-enabled direct ink writing (DIW) printing technology for in-situ curing.
• Copolymerized dicyclopentadiene (DCPD) with a spiroacetal monomer to create acid-degradable resins.
• Evaluated mechanical properties and recyclability of the resulting c-CFRPs.

Main Results:

• Achieved in-situ curing within seconds, reducing energy consumption by two orders of magnitude.
• Developed DCPD-based c-CFRPs with tensile strengths up to 817 MPa and glass transition temperatures over 160 °C.
• Recovered carbon fibers retained over 95% of their original mechanical properties after recycling.
• Demonstrated repolymerization of recovered oligomers into new resins.

Conclusions:

• The innovative FROMP-DIW approach offers a sustainable solution for high-performance thermoset composites.
• This method significantly reduces energy consumption and waste in composite manufacturing.
• Enables closed-loop recycling of c-CFRPs without compromising material performance.