Researchers Create Smart Composite Material from Graphene Oxide and Seaweed-Derived Alginate

Share this Article

[Image: Healthline]

Usually when I think about seaweed, I’m trying to decide which particular sushi roll to order at dinner. But a team of researchers from Brown University in Rhode Island, which is well-versed in unique 3D printing materials, used 3D printing to create a smart composite material out of graphene oxide and alginate derived from seaweed that can change in response to its environment. The team recently published a paper on their new hybrid material, titled “Alginate-graphene oxide hydrogels with enhanced ionic tunability and chemomechanical stability for light-directed 3D printing,” in the Carbon journal.

While seaweed-derived alginate is already used in biomedical applications, hydrogels made from this material are not very strong.

The 3D printing method used to make the material enables the creation of intricate structures like this one, which mimics the atomic lattice of graphene. [Image: Wong Lab, Brown University]

“One limiting factor in the use of alginate hydrogels is that they’re very fragile — they tend to fall apart under mechanical load or in low salt solutions. What we showed is by including graphene oxide nanosheets, we can make these structures much more robust,” explained research leader Thomas Valentin, a PhD student in Brown’s School of Engineering, in a university news release.

Using carbon-based graphene to reinforce the material makes it more robust and durable, so it can be used to help design additional smart materials that respond to external stimuli – making it perfect for use in other applications, such as marine and environmental. The use of stereolithography makes it possible to create stiff, intricate alginate-GO composite structures that are far more fracture resistant than alginate is on its own.

This ability to change the material’s stiffness also makes it a good fit for applications in dynamic cell cultures.

Valentin explained, “You could imagine a scenario where you can image living cells in a stiff environment and then immediately change to a softer environment to see how the same cells might respond.”

Ionic bonds linking the sodium alginate polymers cause the material to dynamically respond to its environment: these bonds are strong enough to keep the material together, but certain chemical treatments can break them apart. The researchers proved this ionic crosslinking in previous experiments, and it can be used to create alginate materials that will rapidly degrade on demand once a chemical treatment “sweeps away ions from the material’s internal structure.”

Once the material has been treated with the chemical that removes its ions, it will swell up and become softer; only after bathing in ionic salts will the ions be restored to make the material stiff again. The researchers found that just by changing up the material’s external ionic environment, they could tune its stiffness over a factor of 500.

According to Ian Y. Wong, an assistant professor of engineering at Brown, graphene oxide can actually change the mechanical properties of alginate structures, which means that the team’s new composite material can be made to be much more resistant to failure caused by cracking. This made it possible to 3D print stiff structures with overhanging parts, which alginate by itself could not do.

“The addition of graphene oxide stabilizes the alginate hydrogel with hydrogen bonding. We think the fracture resistance is due to cracks having to detour around the interspersed graphene sheets, rather than being able to break right though homogeneous alginate,” Wong explained.

Glass coated with alginate-GO was shown to resist fouling by oil.

In addition, the team’s new material is oil-resistant, which means that it could be used as a coating in marine applications to halt oil build-up.

Wong explained, “These composite materials could be used as a sensor in the ocean that can keep taking readings during an oil spill, or as an antifouling coating that helps to keep ship hulls clean.”

The researchers will continue their work with their smart graphene oxide-seaweed hybrid material, including searching for ways to optimize its properties, efficiently mass produce it, and find new uses.

Co-authors of the paper are Valentin, Alexander K. Landauer, Luke C. Morales, Eric M. DuBois, Shashank Shukla, Muchun Liu, and Lauren H. Stephens of Brown University, as well as Christian Franck from the University of Wisconsin and Po-Yen Chen with the National University of Singapore.

Discuss this research and other 3D printing topics at 3DPrintBoard.com or share your thoughts in the comments below.

[Source: Design News]

Share this Article


Recent News

New 3DPrinterOS CEO: Ex-HP 3D Printing and GE Digital Exec Michelle Bockman

3D Printed Sensor Detects COVID-19 Antibodies in 10 Seconds



Categories

3D Design

3D Printed Art

3D Printed Food

3D Printed Guns


You May Also Like

3D Printing News Briefs, September 26, 2020: Nanoscribe, Azul 3D, Arburg

In today’s 3D Printing News Briefs, we’re talking about a new material, a little business, and an industry event. Nanoscribe has introduced a new photoresin with special properties for microoptical...

Featured

Metal 3D Printer Buyer Guide 2020

Metal 3D printing has seen a lot of attention leveled at it over the past several years, with the metal additive manufacturing (AM) market seeing real growth over the past...

3D Printed Milk Made Possible with Cold Extrusion Tech

When it comes to 3D printed food, I really need to stop thinking, “Well, now I’ve seen everything!” Every time I do, I am proven wrong. The latest innovation comes...

Air Force Awards Optomec $1M for High Volume 3D Printing Repair of Turbines

Optomec, a leading provider of additive manufacturing repair solutions, has won a $1 million contract from the U.S. Air Force to produce a system for the refurbishment of turbine engine...


Shop

View our broad assortment of in house and third party products.