Material sheet and process for its preparation

A material sheet obtained from a process comprising:

• (a) unidirectionally aligning a plurality of drawn polymer fibers having a strength of greater than 1.2 GPa thereby forming a monolayer having a thickness of less than 100 μm which is free of a bonding agent, wherein the drawn polymer fibers are aligned such that at least 80 wt. % of the fibers within the monolayer are in abutting contact along at least 30% of fiber length;
• and
• (b) compressing the material sheet under at least 75 bar pressure, such that the abutting fibers of the monolayer are mechanically fused together through mechanical interlocking thereby forming an integral material sheet with interconnected fibers, and wherein
• the fibers are monofilaments or filaments spread from a multifilament yarn, and wherein
• the monolayer has a maximum thickness of no more than 3 times a thickness of an individual fiber.

A tape with a width of between 1 and 250 mm comprising:

• a plurality of drawn unidirectional polymer fibers made from ultra-high molecular weight polyethylene with an intrinsic viscosity as determined on solutions in decalin at 135° C. of a least 4 dl/g, wherein
• at least 80 wt. % of adjacent polymer fibers in the tape are mechanically fused along at least 30% of fiber length through mechanical interlocking, and wherein
• the tape is free of a bonding agent, and wherein
• the fibers are monofilaments or filaments spread from a multifilament yarn, and wherein
• the tape has a maximum thickness of no more than 3 times a thickness of an individual fiber.