An adaptive material invented at Rice University combines self-healing and reversible self-stiffening properties.
The Rice material called SAC (for self-adaptive composite) consists of what amounts to sticky, micron-scale rubber balls that form a solid matrix. The researchers made SAC by mixing two polymers and a solvent that evaporates when heated, leaving a porous mass of gooey spheres. When cracked, the matrix quickly heals, over and over. And like a sponge, it returns to its original form after compression.
The labs of Rice materials scientists Pulickel Ajayan and Jun Lou led the study that appears in the American Chemical Society journal ACS Applied Materials and Interfaces. They suggested SAC may be a useful biocompatible material for tissue engineering or a lightweight, defect-tolerant structural component.
Other “self-healing” materials encapsulate liquid in solid shells that leak their healing contents when cracked. “Those are very cool, but we wanted to introduce more flexibility,” said Pei Dong, a postdoctoral researcher who co-led the study with Rice graduate student Alin Cristian Chipara. “We wanted a biomimetic material that could change itself, or its inner structure, to adapt to external stimulation and thought introducing more liquid would be a way. But we wanted the liquid to be stable instead of flowing everywhere.”
In SAC, tiny spheres of polyvinylidene fluoride (PVDF) encapsulate much of the liquid. The viscous polydimethylsiloxane (PDMS) further coats the entire surface. The spheres are extremely resilient, Lou said, as their thin shells deform easily. Their liquid contents enhance their viscoelasticity, a measure of their ability to absorb the strain and return to their original state, while the coatings keep the spheres together. The spheres also have the freedom to slide past each other when compressed, but remain attached.
“The sample doesn’t give you the impression that it contains any liquid,” Lou said. “That’s very different from a gel. This is not really squishy; it’s more like a sugar cube that you can compress quite a lot. The nice thing is that it recovers.”
Ajayan said making SAC is simple, and the process can be tuned – a little more liquid or a little more solid — to regulate the product’s mechanical behavior.
“Gels have lots of liquid encapsulated in solids, but they’re too much on the very soft side,” he said. “We wanted something that was mechanically robust as well. What we ended up with is probably an extreme gel in which the liquid phase is only 50 percent or so.”
The Latest on: Self-adaptive material
[google_news title=”” keyword=”self-adaptive material” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Self-adaptive material
- Self-healing robotic gripper could be the future of sustainable soft roboticson November 27, 2023 at 11:04 am
Researchers have developed a self-healing robotic gripper for use in soft robotics that is adaptable, recyclable and resilient to damage, thanks to heat-assisted autonomous healing.
- Bioinspired self-assembled colloidal collectives of active matter systemson November 22, 2023 at 4:00 pm
Bioinspired by natural collectives, it is possible to examine colloids as building blocks for materials, much like atoms that form building blocks of molecules and crystals. Colloidal self-assembly ...
- How can you create self-healing materials using nanomachines?on November 20, 2023 at 4:00 pm
Nanomachines can be used to create self-healing materials by embedding them in the material matrix or coating them on the surface. Depending on the type and function of the nanomachines ...
- Self-healing concrete patches up cracks with dormant bacteriaon November 20, 2023 at 12:53 am
Now researchers at Drexel University have demonstrated a type of self-healing concrete embedded ... be crowned the world’s most-used building material without doing a few things right ...
- Self-Tapping Sheet Metal Screwson November 19, 2023 at 4:00 pm
Compare #8 x 1-1/2-inch Square Drive Pan Sock Metal Screw, 500pcs ...
- Impressive new plastic self-heals, can be recycled and feeds marine lifeon November 6, 2023 at 5:47 am
it can self-heal and remember past shapes. Plastic is everywhere in our modern world, for better or worse. Its toughness makes it an extremely useful material for everything from household items ...
- Self Identification Questionnaireon October 31, 2022 at 5:22 am
All parties viewing this information will have committed to confidentiality and will have received guidance related to the confidentiality of these materials. If you should be hired as an employee at ...
- Scientists Just Created a Material for Self-Healing Smartphoneson April 5, 2017 at 10:56 am
has created a self-healing polymeric material for use in soft robotics and electronic devices like smartphones. Chao Wang, Ph.D. presented his team's research yesterday at the 253rd National ...
- Self-healing Materials Marketon October 18, 2016 at 12:10 am
Self-healing materials refer to materials that have the ability to repair damages without human intervention. These materials are inspired from biological systems that display the ability to restore ...
via Bing News