POLYPROPYLENE FIBERS - EXPLORATION OF CONDITIONS RESULTING IN HIGH TENACITY

Paracrystalline as-spun fibres of low orientation were identified prev iously as suitable precursors for the production of drawn fibres of ve ry high tenacity. This study is concerned with the effects of heat tre atment, single-stage and two-stage drawing on the structure and proper ties of the resulting fibres, It is shown that a feasible route to con tinuous filament yarns of high tenacity requires that the orientation of paracrystalline fibres is first increased and only thereafter is th e structure converted into the a-monoclinic form.