Elastomeric composites can flex, grip, release, or rotate when exposed to lasers, diffuse light or sunlight
Researchers at Tufts University School of Engineering have developed magnetic elastomeric composites that move in different ways when exposed to light, raising the possibility that these materials could enable a wide range of products that perform simple to complex movements, from tiny engines and valves to solar arrays that bend toward the sunlight. The research is described in an article published today in the Proceedings of the National Academy of Sciences.
In biology, there are many examples where light induces movement or change – think of flowers and leaves turning toward sunlight. The light actuated materials created in this study are based on the principle of the Curie temperature – the temperature above which certain materials will change their magnetic properties. By heating and cooling a magnetic material, one can turn its magnetism off and on. Biopolymers and elastomers doped with ferromagnetic CrO2 will heat up when exposed to laser or sunlight, temporarily losing their magnetic properties until they cool down again. The basic movements of the material, shaped into films, sponges, and hydrogels, are induced by nearby permanent or electromagnets and can exhibit as bending, twisting, and expansion.
“We could combine these simple movements into more complex motion, like crawling, walking, or swimming,” said Fiorenzo Omenetto, Ph.D., corresponding author of the study and the Frank C. Doble Professor of Engineering in the School of Engineering at Tufts. “And these movements can be triggered and controlled wirelessly, using light.”
Omenetto’s team demonstrated some of these complex movements by constructing soft grippers that capture and release objects in response to light illumination. “One of the advantages of these materials is that we can selectively activate portions of a structure and control them using localized or focused light,” said Meng Li, the first author of the paper, “And unlike other light actuated materials based on liquid crystals, these materials can be fashioned to move either toward, or away from the direction of the light. All of these features add up to the ability to make objects large and small with complex, coordinated movements.”
To demonstrate this versatility, the researchers constructed a simple “Curie engine”. A light actuated film was shaped into a ring and mounted on a needle post. Placed near a permanent magnet, when a laser was focused onto a fixed spot on the ring, it locally demagnetizes that portion of the ring, creating an unbalanced net force that causes the ring to turn. As it turns, the demagnetized spot regains its magnetization and a new spot is illuminated and demagnetized, causing the engine to continuously rotate.
Materials used to create the light actuated materials include polydimethylsoloxane (PDMS), which is a widely used transparent elastomer often shaped into flexible films, and silk fibroin, which is a versatile biocompatible material with excellent optical properties that can be shaped into a wide range of forms – from films to gels, threads, blocks and sponges.
“With additional material patterning, light patterning and magnetic field control, we could theoretically achieve even more complicated and fine-tuned movements, such as folding and unfolding, microfluidic valve switching, micro and nano-sized engines and more,” said Omenetto.
Receive an email update when we add a new ELASTOMERIC COMPOSITES article.
The Latest on: Elastomeric composites
via Google News
The Latest on: Elastomeric composites
- Global Roofing Market: Key Insights and Opportunities Expected to Grow Till 2026 on November 13, 2018 at 1:12 am
In significant new development, leading roofing vendor, TAMCO has lately unveiled its latest collection of roofing products manufactured from fiberglass asphalt and ceramic granules. The product ... […]
- Scientists develop new materials that move in response to light on July 23, 2018 at 9:54 pm
Credit: SilkLab, Tufts University Researchers at Tufts University School of Engineering have developed magnetic elastomeric composites that move in different ways when exposed to light, raising the po... […]
- elastomeric vapor barrier / bituminous / fiberglass-reinforced on June 29, 2018 at 5:28 am
ELASTOVAP is a bituminous vapor barrier composed of glass fiber reinforcement and elastomerci bitumen. The upper face is protected by fine sand and the underside by a thermoplastic film. ELASTOVAP is ... […]
- Chemical and Biological Engineering on May 16, 2018 at 5:00 pm
Accessing improved elastomeric composites filled with functionalized grapheme sheets (FGSs) requires an understanding of how the FGSs aggregate and how the position of FGSs affects the mechanical prop... […]
- Researchers Create Artificial Skin To Give Robots Sense Of Touch on September 13, 2017 at 10:19 am
In the open-access paper titled “Rubbery electronics and sensors from intrinsically stretchable elastomeric composites of semiconductors and conductors,” the researchers wrote: “Rubbery sensors, which ... […]
- Rubbery electronics and sensors from intrinsically stretchable elastomeric composites of semiconductors and conductors on September 8, 2017 at 11:19 am
1 Department of Mechanical Engineering, University of Houston, Houston, TX 77204, USA. 2 Materials Science and Engineering Program, University of Houston, Houston, TX 77204, USA. 3 Department of Elect... […]
- One Component Elastomeric Primer/Adhesive System Meets ISO 10993-5 Specifications on August 8, 2017 at 4:11 am
Developed for priming and bonding polyolefinic substrates, Master Bond X21Med is a single component elastomeric compound that passes ... polyolefins and other surfaces such as metals, ceramics, compos... […]
- Global Elastomeric Coatings Market, 2021 - Research and Markets on April 26, 2017 at 8:23 pm
DUBLIN--(BUSINESS WIRE)--Research and Markets has announced the addition of the "Global Elastomeric Coatings Market" report to ... stiff competition from improved composites and other cost efficient s... […]
- One Component Elastomeric System Features Excellent Thermal Conductivity on November 23, 2016 at 7:03 am
X5TC bonds well to many substrates including metals, glass, composites, ceramics, rubbers and plastics. Since it is elastomeric, this compound is suitable for bonding dissimilar substrates and perform... […]
via Bing News