Liquid crystalline spinning of spider silk

Spider silk has outstanding mechanical properties despite being spun at clo se to ambient temperatures and pressures using water as the solvent The spi der achieves this feat of benign fibre processing by judiciously controllin g the folding and crystallization of the main protein constituents, and by adding auxiliary compounds, to create a composite material of defined hiera rchical structure, Because the 'spinning dope' (the material from which sil k is spun) is liquid crystalline, spiders can draw it during extrusion into a hardened fibre using minimal forces. This process involves an unusual in ternal drawdown within the spider's spinneret that is not seen in industria l fibre processing, followed by a conventional external drawdown after the dope has left the spinneret Successful copying of the spider's internal pro cessing and precise control over protein folding, combined with knowledge o f the gene sequences of its spinning dopes, could permit industrial product ion of silk-based fibres with unique properties under benign conditions.