Effect of the molecular weight of fibre-forming polymers on the mechanical properties of polymer fibres (review)

The effect of the molecular weight of fibre-joining flexible- and rigid-chain polymers on the strength properties of fibres made from them is examined. It was shown that in contrast to high-strength flexible-chain polymer fibres,for which the use of polymers with ultrahigh molecular weights of several million is a necessary condition for sharply increasing the strength, polymers with a normal molecular weight of 20,000-60,000 are used for fabricating high-strength fibres from rigid-chain polymers. Increasing the molecular weight of aromatic polymers during synthesis or by solid-phase afterpolycondensation conducted on the polymer or finished fibre can significantly increase the strength of the fibres.