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A consolidated fibrous structure including a multiplicity of fibrous layers. The fibers of each fibrous layer contain a core and a skin layer. The core has an exterior surface portion containing polypropylene. The skin layer is disposed on at least a portion of the core and contains a first polymer

A consolidated fibrous structure including a multiplicity of fibrous layers. The fibers of each fibrous layer contain a core and a skin layer. The core has an exterior surface portion containing polypropylene. The skin layer is disposed on at least a portion of the core and contains a first polymer and a second polymer. The first polymer contains a polymer having at least 70% α-olefin units and is characterized by a melting temperature lower than the melting temperature of the exterior surface portion of the core. The second polymer contains a co-polymer having at least 50% α-olefin units and is characterized by a number-average molecular weight of about 7,000 g/mol to 50,000 g/mol, a viscosity of between about 2,500 and 150,000 cP measured at 170° C., and a melting temperature lower than the melting temperature of the exterior surface portion of the core. The viscosity of the second polymer is not greater than about 10 percent of the viscosity of the first polymer measured at 170° C. At least a portion of the skin layers of the fibers in each fibrous layer are fused to at least a portion of other skin layers of fibers within the same fibrous layer, at least a portion of the skin layers of the fibers of each fibrous layer are fused with at least a portion of the skin layers of the fibers in an adjacent fibrous layer, and the stiffness of the consolidated fibrous structure is at least 1 N-m. A fibrous layer is also described.

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1. A consolidated fibrous structure comprising at least three (3) fibrous layers, wherein each fibrous layer comprises fibers, wherein the fibers comprise: a core having an exterior surface portion comprising polypropylene;a skin layer disposed on at least a portion of the core, wherein the skin lay

1. A consolidated fibrous structure comprising at least three (3) fibrous layers, wherein each fibrous layer comprises fibers, wherein the fibers comprise: a core having an exterior surface portion comprising polypropylene;a skin layer disposed on at least a portion of the core, wherein the skin layer comprises a first polymer and a second polymer, wherein: the first polymer comprises a polymer having at least 70% α-olefin units and is characterized by a melting temperature lower than the melting temperature of the exterior surface portion of the core; and,the second polymer comprises a co-polymer having at least 50% α-olefin units and is characterized by a number-average molecular weight of about 7,000 g/mol to 50,000 g/mol, a viscosity of between about 2,500 and 150,000 cP measured at 170° C., wherein the viscosity of the second polymer is not greater than about 10 percent of the viscosity of the first polymer measured at 170° C., and a melting temperature lower than the melting temperature of the exterior surface portion of the core;wherein at least a portion of the skin layers of the fibers in each fibrous layer are fused to at least a portion of other skin layers of fibers within the same fibrous layer, at least a portion of the skin layers of the fibers of each fibrous layer are fused with at least a portion of the skin layers of the fibers in an adjacent fibrous layer, and the stiffness of the consolidated fibrous structure is at least 1 N-m measured by ASTM D 790. 2. The consolidated fibrous structure of claim 1, wherein the fibers comprise tape fibers. 3. The consolidated fibrous structure of claim 1, wherein the fibers are high modulus fibers defined as having a tensile modulus of greater than 10 grams per denier. 4. The consolidated fibrous structure of claim 1, wherein the percentage by weight of the second polymer to the consolidated fibrous structure is between about 0.25 and 50%. 5. The consolidated fibrous structure of claim 1, wherein the consolidated fibrous layer comprises at least ten (10) fibrous layers. 6. The consolidated fibrous structure of claim 1, wherein the skin layer is discontinuous on the core. 7. The consolidated fibrous structure of claim 1, wherein the crystallinity of the skin layer is greater than the crystallinity of both the first polymer and the second polymer. 8. The consolidated fibrous structure of claim 1, wherein the melting temperature of the second polymer is lower than the melting temperature of the first polymer. 9. The consolidated fibrous structure of claim 1, wherein the second polymer has a propylene content of greater than 80% by mole. 10. The consolidated fibrous structure of claim 1, wherein each of the fibrous layers comprises interstices between the fibers and wherein the at least a portion of the interstices are filled by a blend of the first polymer and the second polymer, wherein the blend comprises at least 80% wt second polymer. 11. The consolidated fibrous structure of claim 1, wherein the skin layer comprises an interior margin adjacent to the core and an exterior margin remote from the core, wherein the interior margin of the skin layer comprises the first polymer, wherein the exterior margin of the skin layer comprises the second polymer. 12. The consolidated fibrous structure of claim 11, wherein the concentration of the first polymer is greater near the interior margin than at the exterior margin and the concentration of the second polymer is greater near the exterior margin than at the interior margin. 13. The consolidated fibrous structure of claim 11, wherein the concentration of the first polymer decreases in a gradient from the interior margin to the exterior margin. 14. The consolidated fibrous structure of claim 11, wherein the concentration of the second polymer decreases in a gradient from the exterior margin to the interior margin. 15. A consolidated fibrous structure comprising at least three (3) fibrous layers, wherein the fibrous layers comprise fibers in a woven, non-woven, knit, or unidirectional construction, wherein each fibrous layer comprises interstices between the fibers within each fibrous layer, wherein the fibers comprise: a core having an exterior surface portion comprising polypropylene;a skin layer disposed on at least a portion of the core, wherein the skin layer comprises a first polymer and a second polymer, wherein: the first polymer comprises a polymer having at least 70% α-olefin units and is characterized by a melting temperature lower than the melting temperature of the exterior surface portion of the core; and,the second polymer comprises a co-polymer having at least 50% α-olefin units and is characterized by a number-average molecular weight of about 7,000 g/mol to 50,000 g/mol, a viscosity of between about 2,500 and 150,000 cP measured at 170° C., wherein the viscosity of the second polymer is not greater than about 10 percent of the viscosity of the first polymer measured at 170° C., and a melting temperature lower than the melting temperature of the exterior surface portion of the core;wherein at least a portion of the interstices are filled with a blend of the first and second polymers, wherein the blend filling the interstices comprises at least 80% wt the second polymer,wherein at least a portion of the skin layers of the fibers in each fibrous layer are fused to at least a portion of other skin layers of the fibers within the same fibrous layer, at least a portion of the skin layers of the fibers of each fibrous layer are fused with at least a portion of the skin layers of the fibers in an adjacent fibrous layer, and the stiffness of the consolidated fibrous structure is at least 1 N-m measured by ASTM D 790. 16. The consolidated fibrous structure of claim 15, wherein the fibers comprise tape fibers. 17. The consolidated fibrous structure of claim 15, wherein the fibers are high modulus fibers defined as having a tensile modulus of greater than 10 grams per denier. 18. The consolidated fibrous structure of claim 15, wherein the percentage by weight of the second polymer to the consolidated fibrous structure is between about 0.25 and 50%. 19. The consolidated fibrous structure of claim 15, wherein the consolidated fibrous layer comprises at least ten (10) fibrous layers. 20. The consolidated fibrous structure of claim 15, wherein the skin layer is discontinuous on the core. 21. The consolidated fibrous structure of claim 15, wherein the crystallinity of the skin layer is greater than the crystallinity of both the first polymer and the second polymer. 22. The consolidated fibrous structure of claim 15, wherein the melting temperature of the second polymer is lower than the melting temperature of the first polymer. 23. The consolidated fibrous structure of claim 15, wherein the second polymer has a propylene content of greater than 80% by mole. 24. A fibrous layer comprising fibers in a woven, non-woven, knit, or unidirectional construction, wherein the fibers comprise: a core having an exterior surface portion comprising polypropylene; anda skin layer disposed on at least a portion of the core, wherein the skin layer comprises a first polymer and a second polymer, wherein: the first polymer comprises a polymer having at least 70% α-olefin units and is characterized by a melting temperature lower than the melting temperature of the exterior surface portion of the core; and,the second polymer comprises a co-polymer having at least 50% α-olefin units and is characterized by a number-average molecular weight of about 7,000 g/mol to 50,000 g/mol, a viscosity of between about 2,500 and 150,000 cP measured at 170° C., wherein the viscosity of the second polymer is not greater than about 10 percent of the viscosity of the first polymer measured at 170° C., and a melting temperature lower than the melting temperature of the exterior surface portion of the core. 25. The fibrous layer of claim 24, wherein the fibers comprise tape fibers. 26. The fibrous layer of claim 24, wherein the fibers are high modulus fibers defined as having a tensile modulus of greater than 10 grams per denier. 27. The fibrous layer of claim 24, wherein the skin layer is discontinuous on the core. 28. The fibrous layer of claim 24, wherein at least a portion of the skin layers of the fibers in the fibrous layer are fused to at least a portion of other skin layers of the fibers within the fibrous layer. 29. The fibrous layer of claim 24, wherein the melting temperature of the second polymer is lower than the melting temperature of the first polymer. 30. The fibrous layer of claim 24, wherein the second polymer has a propylene content of greater than 80% by mole. 31. A consolidated fibrous structure comprising at least two (2) fibrous layers, wherein each fibrous layer comprises fibers, wherein the fibers comprise: a core having an exterior surface portion comprising polypropylene;a skin layer disposed on at least a portion of the core, wherein the skin layer comprises a first polymer and a second polymer, wherein: the first polymer comprises a polymer having at least 70% α-olefin units and is characterized by a melting temperature lower than the melting temperature of the exterior surface portion of the core; and,the second polymer comprises a co-polymer having at least 50% α-olefin units and is characterized by a number-average molecular weight of about 7,000 g/mol to 50,000 g/mol, a viscosity of between about 2,500 and 150,000 cP measured at 170° C., wherein the viscosity of the second polymer is not greater than about 10 percent of the viscosity of the first polymer measured at 170° C., and a melting temperature lower than the melting temperature of the exterior surface portion of the core;wherein at least a portion of the skin layers of the fibers in each fibrous layer are fused to at least a portion of other skin layers of fibers within the same fibrous layer, at least a portion of the skin layers of the fibers of each fibrous layer are fused with at least a portion of the skin layers of the fibers in an adjacent fibrous layer, and the stiffness of the consolidated fibrous structure is at least 1 N-m measured by ASTM D 790.