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A polymer composition comprising a density equal to or greater than about 0.947 g/cc, a high load melt index from about 1 g/10 min to about 30 g/10 min, and a tensile natural draw ratio less than about 14167 ρ-12958, where ρ is the density (g/cc) of the composition. A polymer composition c

A polymer composition comprising a density equal to or greater than about 0.947 g/cc, a high load melt index from about 1 g/10 min to about 30 g/10 min, and a tensile natural draw ratio less than about 14167 ρ-12958, where ρ is the density (g/cc) of the composition. A polymer composition comprising a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition and wherein less than about 1 weight percent of the composition comprises non-polymeric additives.

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What is claimed is: 1. A polymer composition comprising: a copolymer of ethylene and an alpha-olefin comonomer, wherein the alpha-olefin comonomer comprises propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations ther

What is claimed is: 1. A polymer composition comprising: a copolymer of ethylene and an alpha-olefin comonomer, wherein the alpha-olefin comonomer comprises propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof; a density equal to or greater than about 0.947 g/cc; a high load melt index from about 1 g/10 min to about 30 g/10 min; and a tensile natural draw ratio less than about 14157ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, and wherein the polymer composition comprises a metallocene polyethylene. 2. A polymer composition comprising: a density equal to or greater than about 0.947 g/cc; a high load melt index from about 1 g/10 min to about 30 g/10 min; and a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, wherein the polymer composition comprises a metallocene polyethylene, and wherein the polymer of ethylene comprises a multimodal polymer. 3. The composition of claim 1 further comprising a PENT failure time greater than about 1000 hours. 4. The composition of claim 1 further comprising a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition. 5. The composition of claim 1 further comprising a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition. 6. The composition of claim 1 further comprising a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe. 7. The composition of claim 1 further comprising a Charpy ductile to brittle transition temperature equal to or less than about-25° C. 8. The composition of claim 1 further comprising a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules. 9. The composition of claim 1 comprising less than about 1 weight percent of total non-polymeric additives. 10. A pipe fabricated from a polymer composition comprising: a density equal to or greater than about 0.947 g/cc; a high load melt index from about 1 g/10 min to about 30 g/10 min; and a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, and wherein the polymer composition comprises a metallocene polyethylene. 11. The pipe of claim 10 further comprising a minimum required strength equal to or greater than 10.0 MPa. 12. A polymer composition comprising: two or more molecular weight modes; and a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, wherein less than about 1 weight percent of the composition comprises non-polymeric additives, and wherein the polymer composition comprises a metallocene polyethylene. 13. The composition of claim 12 further comprising a high load melt index from about 1 g/10 min to about 30 g/10 min. 14. The composition of claim 12 further comprising a density equal to or greater than about 0.947 g/cc. 15. The composition of claim 12 further comprising a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition. 16. A pipe fabricated from a polymer composition comprising: a minimum required strength equal to or greater than 10.0 MPa; and a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, wherein less than about 1 weight percent of the composition comprises non-polymeric additives, and wherein the polymer composition comprises a metallocene polyethylene. 17. A polymer composition comprising: a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition; a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition and wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min; and a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition, wherein the polymer composition comprises a metallocene polyethylene. 18. A polymer composition comprising: a density equal to or greater than about 0.947 g/cc; a high load melt index from about 1 g/10 min to about 30 g/10 min; and a tensile natural draw ratio less than about 14167ρ-12958, where ρ is the density (g/cc) of the composition, wherein the tensile natural draw ratio is determined in accordance with ASTM D 638-00 at room temperature using a crosshead speed of 51 mm/min, wherein the polymer composition comprises a metallocene polyethylene, and wherein the metallocene polyethylene is prepared from a dual metallocene catalyst system. 19. The polymer composition of claim 2 further comprising: a PENT failure time greater than about 1000 hours; a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition; and a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition. 20. The polymer composition of claim 19 further comprising: a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe; a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; and a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules. 21. The polymer composition of claim 20 further comprising an alpha-olefin comonomer comprising propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof. 22. The pipe of claim 11 further comprising: a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe; a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; and a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules. 23. The pipe of claim 22 further comprising an alpha-olefin comonomer comprising propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof. 24. The pipe of claim 23 further comprising: a PENT failure time greater than about 1000 hours; a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition; and a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition. 25. The pipe of claim 23 further comprising: a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition; and a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition. 26. The pipe of claim 25 further comprising: a PENT failure time greater than about 1000 hours; a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe; a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; and a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules. 27. The pipe of claim 16 further comprising: a PENT failure time greater than about 1000 hours; and a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe. 28. The pipe of claim 27 further comprising: a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules; a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition; and a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition. 29. The pipe of claim 28 further comprising an alpha-olefin comonomer comprising propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof. 30. The polymer composition of claim 17 further comprising: a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; and a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules. 31. The polymer composition of claim 30 further comprising an alpha-olefin comonomer comprising propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof. 32. The polymer composition of claim 31 further comprising: a PENT failure time greater than about 1000 hours; and a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe. 33. The polymer composition of claim 18 further comprising an alpha-olefin comonomer comprising propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, or combinations thereof. 34. The polymer composition of claim 33 further comprising: a PENT failure time greater than about 1000 hours; a tensile stress at break equal to or greater than 1.10 times the tensile yield stress of the composition; and a rapid crack propagation S4 critical temperature equal to or less than about-1° C. for an 8 inch SDR11 pipe. 35. The polymer composition of claim 34 further comprising: a Charpy ductile to brittle transition temperature equal to or less than about-25° C.; a razor-notched Charpy impact energy at 23° C. of greater than about 0.8 Joules; and a tensile natural draw ratio less than about 25σy-130, where σy is the tensile yield stress of the composition.