Swedish researchers from the Royal Institute of Technology continue to work with wood matter at the nanoscale and are ready to boast of another achievement. Their latest version of the ultra-dense and ultra-strong "nanowood" surpassed the record holder - spider silk. And thus it has become the most durable material of biological origin on the planet.
The subject of interest and work of Swedish scientists: cellulose nanofibrils or CNF. These are tiny formations in the form of fibers, from which the frame of the wood cells is formed at the micro level, which provides them with enviable strength and resistance to all kinds of loads. The task is to artificially give nanofibrils a different form that is useful for humans.
For this purpose, the wood was suspended in channels 1 mm wide, in which deionized water with a low pH level was flowing. The liquid flow washed out the soft fractions and helped the nanofibers align in a single direction, which is why they formed dense bundles. After the final drying, the desired "nanowood" was obtained, which is eight times denser than the original raw material.
In tests, the new material showed a tensile strength of 86 gigapascals and a tensile strength of 1.57 gigapascals. This exceeds the performance of many steel alloys, ceramics, fiberglass, plus the Swedes have significantly improved the strength coefficients of individual fibers in comparison with their previous work. This means that the day is not far off when nanowood will begin to be produced in large quantities for industrial needs.