Titanium Silk

Titanium and other metal oxides can be infused into the protein structure of spider silk fiber to create a new hybrid class of material with greatly increased strength. Spider silk in natural form is both stronger and lighter than steel. The new hybrid is both stronger and more elastic. By adapting a technique known as Atomic Layer Deposition (ALD), a team of scientists at the Max Planc Institute of Microstructure Physics in Germany was able to inject metal oxide ions into the thread, creating a product that requires ten times more energy to break it.

For super-tough spider silk, just add titanium – [newscientist.com]

SPIDER silk is already one of the toughest fibres known, and now it can be made even more resilient with an injection of metal. By infiltrating the protein structure of the silk, the metal makes each strand 10 times as hard to snap.

The same technique might beef up other biomaterials for a host of applications such as making artificial tendons from collagen.

The inspiration comes from the many creatures that have tissues in jaws, stingers and claws strengthened and stiffened by metals. For instance, the mandibles of leaf-cutter ants and locusts are peppered with zinc, and some marine worms have copper in the protein matrix that makes up their jaws.

Does that mean biopolymers such as spider silk and collagen could have their tensile strength improved by introducing metals into their organic matrix? That was the question for a team led by Seung-Mo Lee and Mato Knez at the Max Planck Institute of Microstructure Physics in Halle, Germany.

Metal toughens up spider silk – [rsc.org]

Fritz Vollrath, an expert in the physical and chemical properties of silks from the University of Oxford, UK, say that metal deposition is an interesting approach to strengthening spider silks. ‘This process could be commercially of interest – perhaps not so much for spider silks, which are after all rather impracticable as mass produced fibres, but for silks of the mulberry worms, which are an important commercial fibre already,’ he adds.

‘The spider silk itself is just a model system,’ adds Knez. ‘Once we have learnt to control the deposition system, and really understand what is happening, we hope to apply the method to make better, lighter weight and tougher new materials which are of more interest for technology or medicine,’ he adds.

Metal-infiltrated spider silk to have increased toughness – [fibre2fashion.com]

Even if it has nothing to do with the elevator for the ISS space station, the vision being pursued by NASA in its dream factory, a steel cable that pulls the elevator in a skyscraper on the scale of the Empire State Building, has to carry almost as much in its own weight as it does in the actual elevator cabin. And the higher the buildings, the thicker and heavier the cables become. A material that is as strong as the spider silk infiltrated with metal ions produced by the Max Planck Institute of Microstructure Physics could help with this application.

The fact that spider silk treated with metal ions does not break under enormous tension is just one of the advantages it has to offer: “It can be expanded twice as much as natural spider silk,” says Mato Knez, who is heading the research at the Max Planck Institute. As the treated material withstands high levels of tension and strain, it absorbs ten times more energy than the natural material before it breaks. Thus, it is particularly suitable for braking at full speed or braking free fall, for example in the case of a mountain climber.

Materials with such properties could also be used in aircraft and vehicle construction or in space technology, generally for any application that requires light, strong, and flexible materials. “Our work promises great potential in terms of practical applications, as many other biomaterials can be made more break-resistant and ductile using our method,” explains Mato Knez.

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