This new advancement in science may
help many people who need artificial muscles. Artificial muscles used today do not have a self-healing
capability.In today’s
world, if the material used receives any damage it has to be replaced.Imagine the next generation of materials,
that can heal themselves when damaged.
A revolutionary breakthrough towards
this has been created by Professor Zhenan Bao and her team of researchers at
Stanford. The polymer material is known as an elastomer due to its
stretchiness. When punctured the elastomer self-heals at room temperature. And
when put in an electric field it expands and contracts, like real muscle.
The machine used by Bao could only
stretch the elastomer to a limit of 45 inches. This extremely stretchy polymer
was found to stretch more than 100 inches
after researchers simply pulled the polymer like taffy.In addition to its ability to stretch the
material heals at room temperature and up to (-20
C).This phenomenal material can
be damaged and left to age for days but will still heal.
The stretchiness and resilience of the elastomer are due to the
molecular structure resembling the crosslinking of a fishnet. Metal ions in the
material bind to two or more ligands. According to Bao, if there is a stress on
one part of the structure, the metal ions are still attached to other sites so
the elastomer keeps its form. When the stress is released the metal ions simply
reconnect with the closest ligand. This material could lead to medical implants that will last years without need
of being replaced. Further applications
include robotics and prosthetics. Their research may save lives and help
generations of people to come.
The work was accomplished by Professor Zhenan
Bao, Cheng-Hui Li, Jing-Lin Zuo, Lihua Jin, Yang Sun, Peng Zheng, Yi Cao,
Christian Linder and Xiao-Zeng You.
Written by: Angelica Ramirez
Sources
Bao, Z. (2016). A highly stretchable autonomous self-healing
elastomer. Nature Chemistry.
Several undergraduate research groups from CSUCI presented
their research this year at the 251st ACS meeting in San Diego. Research
projects conducted at the school focus on a variety of topics ranging from environmental
chemistry, organic synthesis, analytical studies, materials science and
instrumentation.
The American Chemical Society national meetings are the
largest scientific conferences in the world. Besides serving as a platform to
present their own scientific work, attending the meetings represents a chance
for students to develop their professional network. Many young students make
connections at ACS meetings that launch their scientific careers into industry
or graduate school.
CSUCI research students and advisors.
From left to right: Chemistry Dean Simone Aloisio, Courtney Mayhew and Timothy Goodman
presenting a project measuring the levels of mercury in rice.
From left to right: Simone Aloisio, Samantha Freitag and Kylan Malloy. Research
concerned with measuring mercury levels in commercial cigarettes was also credited to
Melissa J Soriano, not pictured.
From left to right: Cameron McLaughlin, Angel Torres, Aisling Williams and
Professor Brittnee Veldman, advisor. Research on self-assembling nanocomposite materials.
While attempting to develop a new method to produce
synthetic diamond, scientists at North Carolina State University have discovered
an entirely new phase of carbon called “Q-carbon”. This new material was found
to possess fascinating physical and chemical properties some of which resolve
long-standing scientific mysteries. It is harder than diamond, magnetic at room
temperature, stable at ambient conditions and is electrically conductive. Further,
its production doesn’t require extreme temperature and pressure and it can easily
be converted into conventional diamond.
Phase diagram of carbon. Conventional methods to produce
diamond push graphite into diamond by increasing temperature
and pressure. The dotted green line shows the interface between
supercooled liquid carbon and diamond, which can be crossed
at ambient pressure.
Source: http://dx.doi.org/10.1063/1.4936595
Diamond is an extremely useful material due to its physical
characteristics. Its hardness and clarity lend it to use in a wide variety of
industrial applications such as in abrasives and optics while its thermal and
electrical traits are useful in technological hardware. However, the scarcity
of diamond of appropriate quality in nature forces scientists to look for ways
to mass produce it. The conventional approach requires extremely high
temperatures and pressures along with chemical catalysts. This is extremely
energy-intensive, costly and inefficient.
Researchers Jagdish Narayana and Anagh Bhaumik at North
Carolina State were hoping to find a more straightforward synthetic pathway to
diamond by utilizing a strange quirk of physics called ‘supercooling’. Most
people are familiar with supercooling as it applies to water. A common
demonstration involves placing a bottle of very pure water in the freezer and
taking it out after around two and a half hours. It appears liquid, but upon
hitting it against a surface, it suddenly crystallizes and forms fluffy ice.
This is a slightly different process from the one used for
making Q-carbon, though. While the water demonstration starts in the liquid form,
becomes supercooled liquid and then returns to its normal freezing point to
crystallize into ice, the scientists at NCSU melted solid carbon with a laser
tuned to a highly specific energy. The laser excites the atoms electrically
rather than thermally, and so their crystal structure falls apart at a much
lower temperature than it conventionally would. This liquid carbon was then cooled
extremely rapidly, a process known as ‘quenching’ (hence the “Q” in Q-carbon).
This locked the carbon atoms in their unusual physical arrangement. The rapid
cooling doesn’t allow the atoms any time to form an organized crystal, and thus
Q-carbon was born.
(left) Q-carbon formed by quenching supercooled liquid carbon, (right) a thread
of Q-carbon (white) ending at a crystal of conventional diamond.
Source: http://dx.doi.org/10.1063/1.4936595
Subsequent
characterization experiments revealed its surprising physical properties. Its
magnetic qualities solve an old mystery regarding carbon’s potential as a candidate
for ferromagnetism. Scientists had theoretically predicted it, but it had never
been experimentally verified until now. It is also suggested that because the
physical conditions necessary to produce it exist at the centers of many of our
solar system’s planets, it could potentially be responsible for their magnetic
fields.
The potential applications for this new material are as yet
largely unknown. In any case, its ability to transform into conventional
diamond through a second laser pulse is bound to be useful as it circumvents
the problems of current energy-intensive production methods. Further studies
will certainly need to be done before we can be sure that Q-carbon has
practical use, but if verified, the discovery could prove revolutionary for
technology and industry.
Written by: Aisling M Williams
References
Narayan, J.; Bhaumik, A. Novel Phase of Carbon, Ferromagnetism, and Conversion into Diamond. J. Appl. Phys. Journal of Applied Physics.Dec 2015, 118, 215303.
mrsciguy. "Supercooled Water". Online Video Clip. Youtube. 11 Feb 2016. Web. https://youtu.be/DpiUZI_3o8s
