World's strongest biomaterial shows promise for lightweight structures

The artificial cellulose fibres are claimed to be stronger than steel and dragline spider silk, which is considered the strongest bio-based material. The team led by Daniel Söderberg from the KTH Royal Institute of Technology in Stockholm reports the work in ACS Nano. Söderberg’s team included scientists from Stanford University, Sweden’s RISE institute, the University of Michigan, and the DESY (Deutsches Elektronen-Synchrotron) in Germany.

The ultra-strong bio-degradable material is made of cellulose nanofibres (CNF), which are the  building blocks of wood and other plant life. Using a novel production method, the researchers have transferred the mechanical properties of these nanofibres to a macroscopic, lightweight material.

"Our new material even has potential for biomedicine since cellulose is not rejected by your body", said Söderberg.

The scientists started with commercially available cellulose nanofibres that are two to five nanometres in diameter and up to 700nm long.

The nanofibres were suspended in water and fed into a 1mm wide milled steel channel. Through two pairs of perpendicular inflows additional de-ionized water and water with a low pH-value entered the channel from the sides, squeezing the stream of nanofibres together and accelerating them.