Polypropylene Fibres: Exploration of Conditions Resulting in High Tenacity

Paracrystalline as-spun fibres of low orientation were identified previously as suitable precursors for the production of drawn fibres of very high tenacity. This study is concerned with the effects of heat treatment, single-stage and two-stage drawing on the structure and properties of the resulting fibres. It is shown that a feasible route to continuous filament yarns of high tenacity requires that the orientation of paracrystalline fibres is first increased and only thereafter is the structure converted into the α-monoclinic form.