High modulus through lamellar structures nucleated by flow induced fibrous substrates

Extremely high modulus (up to 10 11 Nm −2 ) strands of poly ethylene have been prepared by the controlled crystallization of lamellar overgrowths onto a small quantity of preformed flow‐induced microfibrils. The requirements for achieving a high modulus from a lamellar system are considered, and indicate that high chain extensions may not be needed. The lamellae satisfying these requirements possess a unique taper, the outer edges having a fold length of less than 40Å. This raises new issues relating to crystallization in confined spaces, and space filling by lamellae in bulk samples in general.