In Sweden, created the paper, which is stronger than iron
The team of scientists from the Swedish Royal Institute of Technology in Stockholm, headed by Lars Berglundom developed a new type of paper, which is stronger than iron, reports New Scientist. Despite the high durability, the new "nanobumaga" made from the same biological material, and that ordinary paper, that is, from cellulose.
In the plant cell walls of individual molecules linked together and cellulose fibers form about 20 nanometers in diameter that in 5000 times thinner than human hair. These fibers form a strong network, which serve as the basis of cell walls.
Wood pulp derived from wood, allowed for the production of paper and cellophane, and has recently begun to apply and to create new plastic materials. But in all these cases pulp is used only as a cheap filler, and its mechanical properties are ignored. However, the methods of processing and wood processing it in the paper significantly reduces the strength of pulp. Therefore, Berglund and his colleagues have developed a more benign technology that preserves the strength fibers.
The new technique involves splitting wood pulp with the help of enzymes and its subsequent fragmented using mechanical "clappers." As a result of split wood, and produced a mixture of water and cellulose fibers intact. Draining water, Berglund found that the fibers are connected to each other through the network of hydrogen bonds and form thin sheets "nanobumagi." Mechanical tests showed that the tensile strength of these sheets on the gap is 214 megapaskaley. For comparison, the strength of the gap is equal to 130 megapaskalyam iron, structural steel from the figure reaches 250 megapaskaley, and the plain paper - 1 megapaskal. When testing strips used by scientists "nanobumagi" 40 mm long, 5 mm in width and thickness of 50 micrometers.
The secret miraculous properties "nanobumagi" lies not only in the strength of cellulose fibers intact, but also in how these fibers are grouped into networks - despite the strong relationship they can shift to one another. Developers suggest that the new paper could be used to strengthen the plain paper, particularly for the production of solid adhesive tape or for building strong synthetic substitutes biological tissues.