Zhou GQ, Shao ZZ, Knight DP, Yan JP, Chen X*

The superior mechanical strength of certain spider dragline silks and of silk reeled artificially silk from silkworm larvae have lead to several attempts to extrude fibres from redissolved silk fibroin. These have, with a single exception, produced fibres weaker than the natural ones. The best process to date produced stronger ones but was unsuitable for industrial scale up. Here we report the development of a novel environmentally friendly spinning process with potential for industrial scale up. The process yields a lustrous silk fibre of circular cross-section, uniform thickness and with molecular orientation and diameter close to that of the natural silk. The tensile strength, extensibility and toughness of the fibres after optimal drawing are equal to or significantly better than those of natural silk fibres.