This is a complete surprise and
we suddenly have a plastic that even behaves like glass. I am sure it will soon be in products
everywhere.
The science of organics continues
to advance strongly and we may soon have glass like flat screen devices
available also.
We are a long ways from the junky
plastics of the past. that I remember turning my nose up as a youth.
What is harder to comprehend is
just how uncomprehending the public is as these marvels just keep seeming to
come along. At least no one is left who
would dare suggest something can not be done.
New Revolutionary Material Can Be Worked Like Glass
ScienceDaily (Nov. 18, 2011) — A common feature of sailboards,
aircraft and electronic circuits is that they all contain resins used for their
lightness, strength and resistance. However, once cured, these resins can no
longer be reshaped. Only certain inorganic compounds, including glass, offered
this possibility until now. Combining such properties in a single material
seemed impossible until a team led by Ludwik Leibler, CNRS researcher at the
Laboratoire "Matière Molle et Chimie" (CNRS/ESPCI ParisTech),
developed a new class of compounds capable of this remarkable feat. Repairable
and recyclable, this novel material can be shaped at will and in a reversible
manner at high temperature.
And, quite surprisingly, it also retains certain properties specific to
organic resins and rubbers: it is light, insoluble and difficult to break.
Inexpensive and easy to produce, this material could be used in numerous
industrial applications, particularly in the automobile, aeronautics, building,
electronics and leisure sectors. This work is published on 18 November 2011
inScience.
Replacing metals by lighter but just as efficient materials is a
necessity for numerous industries, such as aeronautics, car manufacturing,
building, electronics and sports industry. Due to their exceptional mechanical
strength and thermal and chemical resistance, composite materials based on
thermosetting resins are currently the most suitable. However, such resins must
be cured in situ, using from the outset the definitive shape of the part to be
produced. In fact, once these resins have hardened, welding and repair become
impossible. In addition, even when hot, it is impossible to reshape parts in
the manner of a blacksmith or glassmaker.
This is because glass (inorganic silica) is a unique material: once
heated, it changes from a solid to a liquid state in a very progressive manner
(glass transition), which means it can be shaped as required without using
molds. Conceiving highly resistant materials that can be repaired and are
infinitely malleable, like glass, is a real challenge both in economic and ecological
terms. It requires a material that is capable of flowing when hot, while being
insoluble and neither as brittle nor as "heavy" as glass.
From ingredients that are currently available and used in industry
(epoxy resins, hardeners, catalysts, etc.), researchers from the Laboratoire
"Matière Molle et Chimie" (CNRS/ESPCI ParisTech) developed a novel
organic material made of a molecular network with original properties: under
the action of heat, this network is capable of reorganizing itself without altering
the number of cross-links between its atoms. This novel material goes from
the liquid to the solid state or vice versa, just like glass. Until now, only
silica and some inorganic compounds were known to show this type of behavior.
The material thus acts like purely organic silica. It is insoluble even
when heated above its glass transition temperature.
Remarkably, at room temperature, it resembles either hard or soft
elastic solids, depending on the chosen composition. In both cases, it has the
same characteristics as thermosetting resins and rubbers currently used in
industry, namely lightness, resistance and insolubility. Most importantly, it
has a significant advantage over the latter as it is reshapeable at will and
can be repaired and recycled under the action of heat. This property means it
can undergo transformations using methods that cannot be envisaged either for
thermosetting resins or for conventional plastic materials. In particular, it
makes it possible to produce shapes that are difficult or even impossible to
obtain by molding or for which making a mold is too expensive for the envisaged
purpose.
Used as the basis of composites, this new material could therefore
favorably compete with metals and find extensive applications in sectors as
diverse as electronics, car manufacturing, construction, aeronautics or
printing. In addition to these applications, these results shed unexpected
light on a fundamental problem: the physics of glass transition
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