Nav: Home

SUTD develops revolutionary reversible 4D printing with research collaborators

January 29, 2020

Imagine having your curtains extended or retracted automatically without needing to lift a finger?

Reversible 4D printing technology could make these 'smart curtains' a reality without the use of any sensors or electrical devices, and instead rely on the changing levels of heat during the different times of the day to change its shape.

4D printing essentially refers to the ability of 3D printed objects to change its shape over time caused by either heat or water while the reversibility aspect of it allows it to revert to its original shape. However, to have it change back to its original shape usually requires the manual stretching or pulling of the object, which can be laborious and time consuming.

In recent years, there have been successful breakthroughs in the study of reversible 4D printing, where the object gets back its original shape without any human intervention. This usually involved the use of hydrogel as a stimulus to achieve reversible 4D printing.

As hydrogel lacks mechanical strength, it became a limitation when used for load-bearing applications. At the same time, other research work that utilised various layers of material as an alternative to hydrogel, only made the procedure to enable reversible actuation more tedious.

To address these challenges, researchers from the Singapore University of Technology and Design collaborated with Nanyang Technological University to revolutionise 4D printing by making it reversible, without the need for hydrogel nor human interference (refer to video). This paper has been published in the Engineering journal.

This research work utilised only two materials, VeroWhitePlus and TangoBlackPlus, which were more readily available and compatible for printing in a 3D polyjet printer compared to using a hydrogel. The researchers also proved in their paper that the materials were able to retain considerable mechanical strength during and after actuation.

The process consisted of the swelling of elastomer with ethanol to replace the function of hydrogel swelling to induce stress on the transition material. When heated, the transition material changes its shape to a second shape. After the ethanol is being dried out of the elastomer, heating the transition material again will then allow it to revert to its original shape, as the elastomer will pull the transition material back due to elastic energy stored in it after drying.

The elastomer plays a dual function in this whole process. It is used to both to induce stress in the programming stage and to store elastic energy in the material during the recovery stage.

This process of reversible 4D printing has also proven to be more precise when the material reverts to its original shape compared to manually stretching or inducing stress on it. While it is still in its infancy, this breakthrough development provides a wide variety of applications in the future when more mechanisms and more materials become available for printing.

"While reversible 4D printing in itself is a great advancement, being able to use a more robust material while ensuring a more precise reversal during shape change is revolutionary as it allows us to produce complex structures that cannot easily be achieved through conventional fabrication. By relying on environmental conditions instead of electricity, it makes it a game changer across various industries, completely changing the way we design, create, package and ship products," said Professor Chua Chee Kai, lead researcher and Head of Engineering Product Development in SUTD.

Singapore University of Technology and Design

Related Ethanol Articles:

Fractionation processes can improve profitability of ethanol production
The US is the world's largest producer of bioethanol as renewable liquid fuel, with more than 200 commercial plants processing over 16 billion gallons per year.
Ethanol fuels large-scale expansion of Brazil's farming land
A University of Queensland-led study has revealed that future demand for ethanol biofuel could potentially expand sugarcane farming land in Brazil by 5 million hectares by 2030.
Measuring ethanol's deadly twin
ETH Zurich researchers have developed an inexpensive, handheld measuring device that can distinguish between methanol and potable alcohol.
Modified enzyme can increase second-generation ethanol production
Using a protein produced by a fungus that lives in the Amazon, Brazilian researchers developed a molecule capable of increasing glucose release from biomass for fermentation.
Scientists develop a chemocatalytic approach for one-pot reaction of cellulosic ethanol
Scientists at the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences have developed a chemocatalytic approach to convert cellulose into ethanol in a one-pot process by using a multifunctional Mo/Pt/WOx catalyst.
New core-shell catalyst for ethanol fuel cells
Scientists at Brookhaven Lab and the University of Arkansas have developed a highly efficient catalyst for extracting electrical energy from ethanol, an easy-to-store liquid fuel that can be generated from renewable resources.
Yeast makes ethanol to prevent metabolic overload
Why do some yeast cells produce ethanol? Scientists have wondered about this apparent waste of resources for decades.
Corncob ethanol may help cut China's greenhouse gas emissions
A new Biofuels, Bioproducts and Biorefining study has found that using ethanol from corncobs for energy production may help reduce greenhouse gas emissions in China, if used instead of starch-based ethanol.
'Dancing' holes in droplets submerged in water-ethanol mixtures
Researchers from Tokyo Metropolitan University have observed the formation of holes that move by themselves in droplets of ionic liquids (IL) sitting inside water-ethanol mixtures.
Tiny particles increase in air with ethanol-to-gasoline switch
The concentration of ultrafine particles less than 50 nanometers in diameter rose by one-third in the air of São Paulo, Brazil, when higher ethanol prices induced drivers to switch from ethanol to gasoline, according to a new study by a Northwestern University chemist, a National University of Singapore economist and two University of São Paulo physicists.
More Ethanol News and Ethanol Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#569 Facing Fear
What do you fear? I mean really fear? Well, ok, maybe right now that's tough. We're living in a new age and definition of fear. But what do we do about it? Eva Holland has faced her fears, including trauma and phobia. She lived to tell the tale and write a book: "Nerve: Adventures in the Science of Fear".
Now Playing: Radiolab

First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at