| Composite material (240) |  |
| Nacre (22) | |
| Reinforced plastic (8) | |
| Syntactic foam (6) | |
| Composite material (240) | |
| Nacre (22) | |
| Reinforced plastic (8) | |
| Syntactic foam (6) | |
This is called nacre (also known as mother-of-pearl) and it's what gives the shell its strength#the outer surface of the shell is made almost entirely of calcium carbonate
Fran#ois Barthelat studied the internal structure of nacre which is comprised of individual microscopic tablets that interlock in a fashion similar to Lego blocks.
such as nacre or tooth enamel. ur technique is similar to 3d printing, but 10 times faster and much more cost-effective, says Florian Bouville,
Pioneer Award February 23rd, 2015construction Nanoparticles Increase Durability of Concrete Decorations in Cold Areas January 26th, 2015transparent artificial nacre:
#Pimp up my nacre (Nanowerk News) Nacre, or mother of pearl, has highly attractive mechanical properties but cannot be processed into larger-scale structures.
Synthetic nanocomposites can mimic the characteristic brick -and-mortar-like structure of nacre, but combinations of stiffness, strength, toughness and desirable optical properties have remained difficult to achieve.
Scientists based in Aachen, Germany, report in the journal Angewandte Chemie("Hierarchical Nacre Mimetics with Synergistic Mechanical Properties by Control of Molecular Interactions in Self-Healing Polymers")that the introduction of tailored hydrogen bonds in the polymer
mortar by macromolecular engineering leads to an unprecedented combination of the relevant properties, which are perfectly tunable.
In nature, nacre is made a nanocomposite of layers of inorganic microtablets laminated by different biopolymers that stabilize the architecture.
Mankind has used always nacre for decorative purposes, but could not exploit it industrially, despite its generally favorable mechanical properties.
and tweak the nacre nanocomposite structure for possible mechanical and functional applications. Focusing on the laminating polymer phase,
#Transparent artificial nacre: A brick wall at the nanoscale Natural materials have extraordinary mechanical properties,
Scientists have developed now a nacre-inspired nanocomposite that combines exceptional mechanical properties with glass-like transparency and a high gas-and fire-barrier.
The structure of nacre resembles a brick wall at the microscopic scale: Calcium carbonate platelets('bricks')alternate with soft biopolymer layers('mortar'.
Previous approaches to synthesize nacre-mimetics were not feasible on the large scale due to energy-intensive and laborious multistep procedures.
Also, it was not possible to synthesize transparent nacre-mimetic films and foils. Andreas Walther and his team decided to use synthetic nanoclays for their nacre-mimetic materials.
This significantly improved the material's transparency. The Aachen-based research group also refined the underlying preparation procedure"Mussels grow nacre in a lengthy process.
For our nanocomposites, we instead apply a rapid self-assembly process, "the chemist explains. First, the researchers coat the clays with a layer of polyvinylalcohol('mortar on the brick')and subsequently,
"The nacre-mimetics based on small clays are very tough. However, if we use large clays with an aspect ratio of 3500,
the resulting nacre-mimetics are both extremely stiff and strong. Their mechanical properties actually reach close to those of fiber composites,
This outstanding combination of features makes the nacre-mimetic material a promising candidate for future applications,
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