Biosourced photopolymers: print, recycle, repeat

A team at the University of Birmingham has successfully produced a photopolymer resin which can be used in high resolution 3D printing, then recycled and reprinted, using just a small amount of photoinitiator.

Photopolymer resins, often epoxies or acrylics which are derived from petrochemicals, harden on exposure to light and are highly useful in the production of 3D printed components, particularly in the field of rapid prototyping.

In contrast to conventional photopolymer resins, which can be difficult to effectively recycle once printed, the Birmingham team used lipoic acid, a naturally occurring fatty acid, for its resin. Also known as alpha-lipoic acid (ALA), lipoic acid is an organosulfur compound made naturally in the body. It is also commonly sold as a dietary supplement, and indeed the lipoic acid used in the search was obtained from a sports nutrition brand.

A combination of two monomers was produced from the lipoic acid and used to make the resin. After printing, using a MiiCraft Ultra 125 3D printer, the Birmingham team found that the resin was able to be recycled back into either the two monomers or the original molecule.

The ability to use a bio-derived, fully-recyclable polymer in rapid prototyping is potentially a game-changer, and we are pleased to see that Birmingham University has already taken steps to protect their research by filing a patent application covering the polymer and its use.

If you are interested in recent developments in the 3D Printing / Additive Manufacturing industry, why not join us at TCT3Sixty on 6 June 2024? Alternatively, contact one of our AM experts.

Marks & Clerk are members of AMUK, the UK's trade association for organisations who work within the additive and 3D printing eco-system.