Orientation of short fibers in a continuous process

A method of continuously producing fiber reinforced elastomer components having length, depth and width and having fiber orientation at angles to the length direction of said component, the method comprising the sequential steps of

• (a) extruding or injecting a fiber reinforced elastomer comprising elastomer and fibers,
• (b) forcing said elastomer through a die (11) having a gate (12), whereby, due to the length l2 of the gate the fibers (20) will be oriented in the direction of the gate length l2 when the elastomer leaves the gate (12);
• (c) providing an expansion cavity (14) in said die (11) adjacent to said gate (12);
• (d) controlling the viscosity of said elastomer such that the elastomer passes through said gate (12) as a ribbon (16) of elastomer;
• (e) maintaining the orientation of the fibers in the ribbon (16) as it folds in the expansion cavity (14), the fibers ending up oriented in the direction of the height (h1) of expansion cavity (14), whereby the fibers (20) are substantially oriented perpendicular to the width W of the gate and parallel to the height h1 expansion cavity in the of the folded ribbon (16) forming the fiber reinforced elastomer component;
• (f) collecting said component for storage or for direct use in an elastomeric product,
• characterized in that the gate (12) has a gap height h2 larger than the average length of said fibers;
• in that the viscosity of said elastomer as the elastomer enters the gate (12) is maintained at Mooney viscosity of 30 to 80, and
• in that the elastomer is processed at a speed of 100 to 1000 nm/sec linear speed at the gate (12) and 1 to 100 mm/sec in the expansion cavity (14).