3D Printing Machine Training
Published

Birmingham Researchers Develop Recyclable Photopolymer Resin Made From Biosourced Materials

A University of Birmingham-led team has produced a photopolymer resin that can be printed at high resolution, broken down to its constituent parts, recycled and reprinted.

Share

A 3D printed complex part made from the entirely bio-sourced feedstock. Source: University of Birmingham

A 3D printed complex part made from the entirely biosourced feedstock. Source: University of Birmingham

Researchers at the University of Birmingham have succeeded in producing a new type of recyclable photopolymer resin, made from biosourced materials. The new resin can be printed at high resolution and then be broken back down to its constituent parts, recycled and reprinted, with the addition of just a small amount of photoinitiator to maintain the material’s curable properties.

Photopolymer resins, which harden or cure on exposure to light, are commonly used in the manufacture of bespoke 3D printed parts. However, while technologies to improve the resolution of 3D printing and its speed of manufacture have advanced considerably, the resins themselves have changed very little since the process first emerged in the 1980s.

The basic materials — usually epoxies or acrylics — come mostly from petrochemical feedstocks. Although some progress has been made in the use of more sustainable resins derived from biomass, the recyclability of these is still limited, because they rely on irreversible bonds being created when the resin hardens. To break these bonds, additional chemicals have to be added at each stage, resulting in a “snowballing effect,” in which the only way to recycle the material is to make more of it.

Now, this new type of recyclable resin, made from biosourced materials, has been designed for use in 3D printing applications. In a study, published May 15, 2024, in Nature, researchers from the University of Birmingham showed that high-resolution, 3D printed structures can be manufactured from an entirely biosourced feedstock. Once these materials have reached the end of their useful life, the products can be recycled within an almost fully closed-loop system.

“Our approach is an important step away from relying on 3D-printable resins made from petrochemicals, which cannot be efficiently recycled,” says Andrew Dove, lead researcher and professor of sustainable polymer chemistry. “While we still have improvements to make to the properties of the new resin, this research opens up exciting new avenues for development.”

The feedstock for the process is made from lipoic acid, a naturally occurring fatty acid molecule which is commonly sold as a dietary supplement. The team made a combination of two monomers from the lipoic acid from which they were able to make a resin that could be recycled either back into the monomers or right back to the original molecule for recycling.

In the study, the researchers completed two ‘recycles,’ but anticipate that further recycles would be possible. Uses for the material could include industries where rapid prototyping is used to test products before moving to mass production. Although currently the material is more flexible than might be commonly used in industry, future applications could include automotive parts, medical and dental components, and even jewelry design.

“Enabling recycling within the light-mediated 3D printing industry is essential since it is a rapidly expanding method for materials production,” says Josh Worch, co-lead researcher and assistant professor. “We now have the prospect, with our technology, to help ensure that recycling becomes a built-in feature of 3D printing.”

The University of Birmingham Enterprise has filed a patent application covering the resin and its use in 3D printing.

Airtech
Acquire
UPM Additive Solutions
The World According To
The Cool Parts Show
AM Radio

Related Content

Sponsored

3D Printing with Plastic Pellets – What You Need to Know

A few 3D printers today are capable of working directly with resin pellets for feedstock. That brings extreme flexibility in material options, but also requires greater knowledge of how to best process any given resin. Here’s how FGF machine maker JuggerBot 3D addresses both the printing technology and the process know-how.

Read More
Polymer

3D Printing Startup to Deliver Thousands of Custom Hearing Aids Over Next Five Years

Starting with a pilot program in Jordan, nonprofit 3DP4ME is developing workflows to 3D print hearing aid earmolds and prosthetics near the people who need them.

Read More
Polymer

Possibilities From Electroplating 3D Printed Plastic Parts

Adding layers of nickel or copper to 3D printed polymer can impart desired properties such as electrical conductivity, EMI shielding, abrasion resistance and improved strength — approaching and even exceeding 3D printed metal, according to RePliForm.

Read More
Polymer

Airless Basketball Shows Promise of 3D Printed Lattices: The Cool Parts Show Bonus

Successfully matching the performance of a standard basketball demonstrates the control possible over the mechanical properties of digital materials.

Read More

Read Next

Artificial Intelligence

Carnegie Mellon Helps Industry, Students Prepare for a Manufacturing Future with AM and AI

Work underway at the university’s Next Manufacturing Center and Manufacturing Futures Institute is helping industrial additive manufacturers achieve success today, while applying artificial intelligence, surrogate modeling and more to solve the problems of the future.

Read More
Design

3MF File Format for Additive Manufacturing: More Than Geometry

The file format offers a less data-intensive way of recording part geometry, as well as details about build preparation, material, process and more.

Read More
Metal

Postprocessing Steps and Costs for Metal 3D Printing

When your metal part is done 3D printing, you just pull it out of the machine and start using it, right? Not exactly. 

Read More
3D printing machine trainings