The polyethylene according to the present disclosure has a molecular structure having a narrow particle distribution and a low content of ultra-high molecular weight, so that a chlorinated polyethylene having excellent chlorination productivity and thermal stability may be prepared by reacting the polyethylene with chlorine. And, a PVC composition including the same with improved impact strength may also be prepared.

In some embodiments, the present disclosure provides a composition comprising from 5 phr to 30 phr of a PEDM terpolymer having 1 to 10 wt % diene, 13 to 40 wt % ethylene, and 15 to 85 wt % propylene, based on the weight of the PEDM terpolymer. The composition further comprises from 70 phr to 95 phr of an ethylene-based copolymer comprising an ethylene content different than the first polymer, a C.sub.3 to C.sub.12 α-olefin, and, optionally, one or more dienes.

Embodiments of the present disclosure are directed towards catalyst formulations including a metallocene and a stearic compound selected from bis 2-hydroxyethyl stearyl amine, aluminum distearate, and combinations thereof, where the metallocene is represented by the following formula: (Formula (I)) wherein each n-PR is n-propyl, and each X is independently CH.sub.3, Cl, or F.

##STR00001##

The present disclosure provides catalyst systems having a bridged metallocene compound and a transition metal pyridyldiamide compound for use in alkene polymerization to produce multimodal polyolefins, such as multimodal ethylene, propylene, diene monomer copolymers. In some embodiments, the present disclosure provides for polyolefins and processes for producing a polyolefin composition including contacting at least one olefin with a catalyst system of the present disclosure.

Provided are a novel metallocene-supported catalyst and a method of preparing a polyolefin using the same. The metallocene-supported catalyst according to the present disclosure may be used in the preparation of polyolefins, it may have excellent activity and excellent reactivity with comonomers, and it may prepare olefinic polymers having a high molecular weight and a low molecular weight.

The present invention relates to a method for evaluating an injection physical property of a plastic resin, and a polyethylene resin suitable for an injection molding process and, more particularly, to a novel method for evaluating an injection physical property of a plastic resin, which, when a particular plastic resin is processed by an injection process, can accurately derive injection suitability of the plastic resin and injection pressure in the injection process through a physical property value measured by using a resin specimen, and a polyethylene resin suitable for injection molding.

A mixed metallocene catalyst system can comprise at least one metallocene catalyst compound comprising a structure represented by formula (A) below and optionally at least one other metallocene catalyst compound having a structure represented by formula (B) below:

##STR00001##

A mixed metallocene catalyst system can additionally include a non-coordinating anion type activator comprising a supported alumoxane or aluminum alkyl, and optionally a scavenger. A process for making a polymeric product can comprise: contacting a C.sub.2-C.sub.22 alpha-olefin feed with the catalyst system to obtain a polymerization reaction mixture; and obtaining a polymer product from the polymerization reaction mixture. A polymer product can be made by the process.

A metallocene catalyst compound can comprise a structure represented by formula (F-MC) below comprising a first cyclopentadienyl ring with carbon atoms directly connected with R.sup.1, R.sup.2, R.sup.4, and R.sup.5, and a second cyclopentadienyl ring with carbon atoms directly connected with R.sup.10, R.sup.11, R.sup.12, and R.sup.13, and a bridging group (BG) directly connecting the first and second cyclopentadienyl rings

##STR00001##

A catalyst system can include the metallocene compound, a non-coordinating anion type activator comprising a supported alumoxane or aluminum alkyl, and optionally a scavenger. A process for making a polymeric product can comprise: contacting a C.sub.2-C.sub.22 alpha-olefin feed with the catalyst system to obtain a polymerization reaction mixture; and obtaining a polymer product from the polymerization reaction mixture. A polymer product can be made by the process to exhibit at least an Mn from 7,000 g/mol to 70,000 g/mol and a PDI from 4.1 to 9.0.

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 conent 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.

A polyethylene according to the present disclosure maintains a stable crystal structure at a high temperature and ensures excellent uniformity in chlorine distribution, thereby preparing a chlorinated polyethylene having excellent chlorination productivity and thermal stability by reacting with chlorine, and may also prepare a PVC compound with improved impact strength by including the chlorinated polyethylene.