Carrot concrete and bullet-proof wood: scientists have created heavy-duty materials from natural fabrics – The Economist
Biological tissues replace traditional polymers, giving the opportunity to create stronger materials for the construction and production of goods.
Make concrete from carrots, turn wood into plastic or even squeeze it so that it turns into a “super wood” that will be many times lighter and stronger than titanium – all this sounds like something in the spirit of Frankenstein’s experiments. However, all these transformations are the latest example of the use of plant tissues to create environmentally friendly artificial materials or impurities, writes The Economist. Scientists have found that plant tissues can increase the service life and strength of substances that are already used in the construction and production of various products: from toys to furniture, cars and airplanes. A great advantage is also the fact that plants bind carbon in their structure, and consequently the use of their tissues means a reduction in CO2 emissions. Only cement production accounts for 5% of carbon emissions caused by mankind. And the process of making a kilogram of plastic from petroleum products is accompanied by the release of six kilograms of greenhouse gases.
The publication says that scientists have found an unusual use of carrots. In particular, she was studied by Mohamed Saafi from the University of Lancaster. Doctors Saafi and his colleagues were not interested in the whole carrot, but what they called “nano-platelets”, which were extracted from plants not suitable for sale or carrot waste at processing plants. The sugar beet robe is also a good source of nano-platelets. Researchers are working with CelluComp, which has found an industrial application for these plant tissues. In particular, the company produces additives that strengthen the paint after drying. Each nanothrombocyte has an area of one millionth of a meter. It consists of a layer of rigid cellulose tissues. Despite the small size, these elements are very durable. If they are combined with other materials, an extremely hard substance can be obtained. Dr. Saafi mixes nano-platelets with cement, which is made by burning clay and limestone at high temperatures. Usually, cement is mixed with gravel, sand and water to produce a liquid concrete that cures with drying. But if you add vegetable nanotrbocytes to the mixture, you get something stronger. Scientists say that biological material itself strengthens concrete, so less cement can be used to make it. And this allows to reduce CO2 emissions in the atmosphere during its production. To obtain a cubic meter of concrete, it is sufficient to add 500 grams of nanotub- bocytes in order to reduce the use of cement by 40 kilograms. Dr. Saafi, over the next two years, is going to determine what proportion of the natural particles found in building materials will be the most optimal for builders.
For wood, scientists also found a new more effective application. It consists of cellulose fibers embedded in a matrix of lignin – an organic polymer that makes the trees solid and durable. The Finnish company May Stora Enso has started the production of a substitute for traditional plastic based on lignin. The material was called DuraSense. Outwardly it resembles popcorn and consists of wood fibers, in particular lignin. It is mixed with oil-based polymers to result in pellets that can be melted and bent in the process of making things, like plastic.
In the Finnish company argue that the use of wood fibers can reduce the use of plastic in the production of goods up to 60%. In May Stora Enso also found application for the lignin itself, which often gets into waste during the production of paper. Its Finnish engineers used as a substitute for oil resins and glue in the production of wood plastics. Also, the Finnish company is looking for a way to replace lignin with petroleum products in carbon fiber, which is used to manufacture parts for cars and airplanes. At this time, at the University of Maryland, scientists Hu Lianbin and Li Shan are trying to create the best material by removing lignin from the wood. The goal is to remove the maximum amount of this substance from the blocks of wood so that it can be easier to compress. Blocks are compressed at a temperature of 100 degrees Celsius, which causes the pores in the wood to break. Thus, the density of wood triples, and the strength increases by 11 times. This puts such a “super wood” on one step with some light alloys of titanium, which is used in aerospace components. In addition, such wood is bulletproof.