Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

ORNL thermomagnetic processing method provides path to new materials

07.11.2014

For much the same reason LCD televisions offer eye-popping performance, a thermomagnetic processing method developed at the Department of Energy’s Oak Ridge National Laboratory can advance the performance of polymers.

Polymers are used in cars, planes and hundreds of consumer products, and scientists have long been challenged to create polymers that are immune to shape-altering thermal expansion. One way to achieve this goal is to develop highly directional crystalline structures that mimic those of transparent liquid crystal diode, or LCD, films of television and computer screens.


The high magnetic field environments are provided by fully recondensing commercial prototype superconducting magnet processing system. The electromagnetic fields turn and align the liquid crystal phase forming a pseudo super-structure of ordered domains. This leads to advanced physical properties such as near-zero coefficient of thermal expansion.

Unfortunately, polymers typically feature random microstructures rather than the perfectly aligned microstructure – and transparency – of the LCD film.

ORNL’s Orlando Rios and collaborators at Washington State University have pushed this barrier aside with a processing system that changes the microstructure and mechanical properties of a liquid crystalline epoxy resin.

Their finding, outlined in a paper published in the American Chemical Society journal Applied Materials and Interfaces, offers a potential path to new structural designs and functional composites with improved properties.

The method combines conventional heat processing with the application of powerful magnetic fields generated by superconducting magnets. This provides a lever researchers can use to control the orientation of the molecules and, ultimately, the crystal alignment.

“In this way, we can achieve our goal of a zero thermal expansion coefficient and a polymer that is highly crystalline,” said Rios, a member of ORNL’s Deposition Science Group. “And this means we have the potential to dial in the desired properties for the epoxy resin polymers that are so prevalent today.”

Epoxy is commonly used in structural composites, bonded magnets and coatings. Rios noted that thermosets such as epoxy undergo a chemical cross-linking reaction that hardens or sets the material. Conventional epoxy typically consists of randomly oriented molecules with the molecular chains pointing in every direction, almost like a spider web of atoms.

“Using thermomagnetic processing and magnetically responsive molecular chains, we are able to form highly aligned structures analogous to many stacks of plates sitting on a shelf,” Rios said. “We confirmed the directionality of this structure using X-ray measurements, mechanical properties and thermal expansion.”

Co-authors of the paper, “Thermomagnetic processing of liquid crystalline epoxy resins and their mechanical characterization using nanoindentation,” are Yuzhan Li and Michael Kessler of Washington State’s School of Mechanical and Materials Engineering.

The ORNL portion of the research was supported by the Critical Materials Institute, an Energy Innovation Hub funded by DOE’s Office of Energy Efficiency and Renewable Energy. Washington State’s research was funded by the Air Force Office of Scientific Research.

UT-Battelle manages ORNL for the Department of Energy's Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit http://science.energy.gov/ 

Ron Walli | EurekAlert!
Further information:
http://www.ornl.gov/ornl/news/news-releases/2014/ornl-thermomagnetic-processing-method-provides-path-to-new-materials

More articles from Materials Sciences:

nachricht An innovative high-performance material: biofibers made from green lacewing silk
20.01.2017 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

nachricht Treated carbon pulls radioactive elements from water
20.01.2017 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>