Resins for Frontal Photopolymerization: Combining Depth-Cure and Tunable Mechanical Properties

Area of Science:

• Polymer Chemistry
• Materials Science
• Photochemistry

Background:

• Photopolymerization is limited by shallow curing depths, hindering large-volume production.
• Frontal photopolymerization (FPP) offers a solution for rapid, deep curing of polymers.
• Tailored resins are crucial for effective FPP but are not yet commercially available.

Purpose of the Study:

• To investigate the potential of long-chain polyether dimethacrylates as crosslinkers in photobleaching resins for FPP.
• To analyze the mechanical properties of photofrontally-cured copolymers.
• To demonstrate the feasibility of deep curing and versatile material property generation using FPP.

Main Methods:

• Synthesis and characterization of photobleaching resins using long-chain polyether dimethacrylates.
• Photofrontally cured copolymerization of developed resins.
• Mechanical testing (tensile tests) of cured materials.
• Fourier transform infrared spectroscopy and swelling tests to analyze polymerization depth and uniformity.

Main Results:

• Long-chain polyether dimethacrylates enable low optical density and photobleaching properties suitable for FPP.
• Achieved versatile mechanical properties in cured copolymers, ranging from ductile to hard and brittle.
• Demonstrated uniform polymerization over a depth of 4 cm in analyzed components.

Conclusions:

• Frontal photopolymerization is a viable technique for deep curing of centimeter-thick polymer layers.
• The developed resins show promise for producing materials with tunable properties via FPP.
• FPP facilitates rapid, large-volume production of polymers with controlled characteristics.