Chinese researchers develop superstrong artificial silk

TIANJIN, Oct. 28 (Xinhua) -- Chinese researchers have found a novel way to develop superstrong artificial silkworm silk that exhibits significantly higher strength than the strongest natural silk.

Silkworm silk is also widely used in biomedicine as surgical materials and in tissue generation tests. Silks are protein-based biopolymers with unique combinations of different physical properties. Silkworm silk has a weaker strength than the strongest natural silk -- spider dragline silk, which makes up the main scaffolding of a spider's web.

Scientists have been trying to incorporate spider DNA into silkworms to increase their silk's tensile strength. In the new research published in the journal Matter, researchers from China's Tianjin University chose the common silkworms that are more accessible and easily managed to make the artificial silk.

The natural silkworm silk fiber is made up of a core fiber covered in silk glue, which prevents the fibers from being spun for commercial use. The researchers put silk from the common silkworm in a chemical bath that could dissolve the glue while limiting the degradation of the silk proteins.

The researchers said that the artificial fibers are smooth and strong and could bear force. They are 70 percent stronger than spider silks.

Structural analysis indicates that the extraordinary strength may be ascribed to high crystallinity and small nanocrystals formed in the artificial fibers. The incorporation of zinc ions into the fiber during spinning and post-spinning drawing may also contribute to its excellent mechanical properties, according to the researchers.

They said they hope their new approach can offer a promising way to produce profitable high-performance artificial silks.