A polyethylene comprising of ethylene derived units and 0.5 wt % to 10 wt % C.sub.3 to C.sub.12 α-olefin derived units may be synthesized using a mixed catalyst that comprises rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride and a zirconium co-catalyst in a mole ratio of 50:50 to 90:10, and wherein the zirconium co-catalyst is a poor comonomer incorporator as compared to the rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride catalyst. Such a polyethylene may have a density of 0.91 g/cm.sup.3 to 0.93 g/cm.sup.3, an I.sub.2 value of 0.5 g/10 min to 2 g/10 min, an I.sub.21 value of 25 g/10 min to 75 g/10 min, an I.sub.21/I.sub.2 ratio of 25 to 75, a molar reversed-co-monomer index (RCI,m) of 30 to 180, a phase angle equal or lower than 70° at complex modulus G* of 10,000 Pa, a Θ.sub.2 of 1.5 radians to −1.5 radians, and a low density population of 50% and 70% by weight of the polyethylene.

A polyethylene comprising of ethylene derived units and 0.5 wt % to 10 wt % C.sub.3 to C.sub.12 α-olefin derived units may be synthesized using a mixed catalyst that comprises rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride and a zirconium co-catalyst in a mole ratio of 50:50 to 90:10, and wherein the zirconium co-catalyst is a poor comonomer incorporator as compared to the rac-dimethylsilylbis(tetrahydroindenyl)zirconium dichloride catalyst. Such a polyethylene may have a density of 0.91 g/cm.sup.3 to 0.93 g/cm.sup.3, an I.sub.2 value of 0.5 g/10 min to 2 g/10 min, an I.sub.21 value of 25 g/10 min to 75 g/10 min, an I.sub.21/I.sub.2 ratio of 25 to 75, a molar reversed-co-monomer index (RCI,m) of 30 to 180, a phase angle equal or lower than 70° at complex modulus G* of 10,000 Pa, a Θ.sub.2 of 1.5 radians to −1.5 radians, and a low density population of 50% and 70% by weight of the polyethylene.

Ethylene-based polymers having a density from 0.94 to 0.96 g/cm.sup.3, a Mn from 5,000 to 14,000 g/mol, a ratio of Mw/Mn from 18 to 40, and at least one of a PENT value at 2.4 MPa of at least 11,500 hr and/or a W90 from 7.5 to 15 wt. % are disclosed. Additional ethylene polymers can have the same density, Mn, and Mw/Mn values, as well as a relaxation time from 0.5 to 3.5 sec, a CY-a parameter from 0.48 to 0.68, a HLMI from 5 to 11 g/10 min, a viscosity at HLMI from 3,000 to 7,500 Pa-sec, and a higher molecular weight component (HMW) and a lower molecular weight (LMW) component, in which a ratio of the number of SCBs at Mp of the HMW component to the number of SCBs at Mp of the LMW component is from 3.5 to 8.

Ethylene-based polymers having a density from 0.94 to 0.96 g/cm.sup.3, a Mn from 5,000 to 14,000 g/mol, a ratio of Mw/Mn from 18 to 40, and at least one of a PENT value at 2.4 MPa of at least 11,500 hr and/or a W90 from 7.5 to 15 wt. % are disclosed. Additional ethylene polymers can have the same density, Mn, and Mw/Mn values, as well as a relaxation time from 0.5 to 3.5 sec, a CY-a parameter from 0.48 to 0.68, a HLMI from 5 to 11 g/10 min, a viscosity at HLMI from 3,000 to 7,500 Pa-sec, and a higher molecular weight component (HMW) and a lower molecular weight (LMW) component, in which a ratio of the number of SCBs at Mp of the HMW component to the number of SCBs at Mp of the LMW component is from 3.5 to 8.

The present disclosure relates to a method for preparing a polyolefin using a supported hybrid metallocene catalyst. According to the present disclosure, a polyolefin having a narrow molecular weight distribution can be prepared very effectively by introducing a cocatalyst in an optimum content in the presence of a supported hybrid metallocene catalyst containing two or more metallocene compounds having a specific chemical structure. The polyolefin prepared according to the present disclosure exhibits excellent uniformity in chlorine distribution in polyolefin during chlorination, thereby significantly improving elongation of the chlorinated polyolefin, compatibility with PVC and impact reinforcing performance. Thus, it exhibits excellent chemical resistance, weather resistance, flame retardancy, processability and impact strength reinforcing effect, and can be suitably applied as an impact reinforcing agent for PVC pipes and window profiles.

The present disclosure relates to a method for preparing a polyolefin using a supported hybrid metallocene catalyst. According to the present disclosure, a polyolefin having a narrow molecular weight distribution can be prepared very effectively by introducing a cocatalyst in an optimum content in the presence of a supported hybrid metallocene catalyst containing two or more metallocene compounds having a specific chemical structure. The polyolefin prepared according to the present disclosure exhibits excellent uniformity in chlorine distribution in polyolefin during chlorination, thereby significantly improving elongation of the chlorinated polyolefin, compatibility with PVC and impact reinforcing performance. Thus, it exhibits excellent chemical resistance, weather resistance, flame retardancy, processability and impact strength reinforcing effect, and can be suitably applied as an impact reinforcing agent for PVC pipes and window profiles.

The polyethylene according to the present invention has narrow particle size distribution, and can minimize a change in the crystal structure, and thus, it can be reacted with chlorine to prepare chlorinated polyethylene having excellent chlorination productivity and thermal stability.

The polyethylene according to the present invention has narrow particle size distribution, and can minimize a change in the crystal structure, and thus, it can be reacted with chlorine to prepare chlorinated polyethylene having excellent chlorination productivity and thermal stability.

The present invention relates to an olefin-based polymer, which has (1) a density (d) ranging from 0.85 to 0.90 g/cc, (2) a melt index (MI, 190° C., 2.16 kg load conditions) ranging from 0.1 g/10 min to 15 g/10 min, (3) the density (d) and the melt temperature (Tm) satisfying Tm (° C.)=a×d−b of Equation 1 (2,350<a<2,500, and 1,900<b<2,100), and (4) a ratio (hardness/Tm) of the hardness (shore A) to the melt temperature (Tm) in a range of 1.0 to 1.3. The olefin-based polymer according to the present invention exhibits excellent anti-blocking properties due to having improved hardness as a low-density olefin-based polymer.

The present invention relates to polyolefin. More specifically, the present invention relates to polyolefin having excellent dart drop impact strength, and exhibiting improved transparency, and such polyolefin has a density of 0.915 g/cm3 to 0.930 g/cm3 measured according to ASTM D1505; and satisfies the following requirements (provided that S1+S2+S3=1), when measuring the relative content of peak area according to melting temperature (Tm) using SSA (Successive Self-nucleation and Annealing) analysis: the content(S1) of peak area at Tm less than 100° C. is 0.33 to 0.35; the content(S2) of peak area at Tm of 100° C. or more and 120° C. or less is 0.52 to 0.56; and the content(S3) of peak area at Tm greater than 120° C. is 0.10 to 0.14.