A method of making an olefin polymerization catalyst carrier with a general structure formula of Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, wherein: 0n2, and R.sup.I and R.sup.II can be the same or different and are each independently selected from a C.sub.1-C.sub.20 hydrocarbon group by reacting an alcohol with a metal magnesium powder under the protection of nitrogen in the presence of a halogen or a halogen-containing compound to obtain a first product, and subjecting the product to a treatment pressure of from 0.2 to 5.0 MPa at a treatment temperature of from 80 to 200 C. for a duration of between 2 minutes and 6 hours. Also provided is a method of making an olefin polymerization solid catalyst component which includes the catalyst carrier, a titanium compound, and at least one electron donor compound.

The activity of an in situ prepared Ziegler Natta catalyst in a solution polymerization may be tuned on a continuous basis by monitoring the catalyst activity (conversions) and on a frequent periodic basis incrementally adjusting the alkyl halide in the catalyst to optimize the activity.

The disclosure provides an ethylene copolymer having a density of from 0.912 g/cm.sup.3 to 0.925 g/cm.sup.3, a melt flow ratio (I.sub.21/I.sub.2) of from 20 to 30, and a normal comonomer distribution profile in a GPC-FTIR analysis, wherein the normal comonomer distribution profile has a slope of from 3.5 to 7.5, where the slope is defined as the number of short chain branches per 1000 carbons at a molecular weight of 300,000 minus the number of short chain branches per 1000 carbons at a molecular weight of 30,000. The ethylene copolymers have improved bulk density and when made into film, provide good physical properties.

The present disclosure generally relates to ethylene alpha-olefin copolymers and methods of making ethylene alpha-olefin copolymers. The ethylene alpha-olefin copolymers may have a density of about 0.915 g/mL to about 0.918 g/mL, a rheological polydispersity index greater than 0.8, a melt index of about 0.4 dg/10 min to about 2.0 dg/10 min, and/or a CEF T.sub.50 of 84 C. or less. The ethylene alpha-olefin copolymers may be made by combining an ethylene monomer and one or more alpha-olefin monomers in the presence of a catalyst, such as a Ziegler-Natta catalyst.

The present disclosure relates to a solid catalyst component for the polymerization of olefins comprising Mg, Ti and an electron donor of the formula (I): ##STR00001##
where each Q is a group COOR.sup.1, in which R.sup.1 is selected from C.sub.1-C.sub.15 hydrocarbon groups, optionally containing a heteroatom selected from the group consisting of halogens, P, S, N and O; or a group CON(R.sup.2).sub.2, in which R.sup.2 groups, equal to or different from each other, are hydrogen or R.sup.1 groups which can be fused together to form one or more cycles, and A is a bivalent bridging group with the proviso that the Q groups cannot be simultaneously a group COOR.sup.1 or CON(R.sup.2).sub.2.

A catalyst composition and a process for obtaining a colored olefin polymer are disclosed. The composition comprises a Ziegler-Natta catalyst and an additive component comprising a colorant. The catalyst composition enables a directly colored polymer to be prepared. The colored polymer has a homogeneous dispersion of the colorant in it and thus has no color defects.

A catalyst composition and a process for obtaining a colored olefin polymer are disclosed. The composition comprises a Ziegler-Natta catalyst and an additive component comprising a colorant. The catalyst composition enables a directly colored polymer to be prepared. The colored polymer has a homogeneous dispersion of the colorant in it and thus has no color defects.

The present disclosure relates to a solid catalyst component for the polymerization of olefins comprising Mg, Ti and an electron donor of the formula (I):

##STR00001##

where each Q is a group COOR.sup.1, in which R.sup.1 is selected from C.sub.1-C.sub.15 hydrocarbon groups, optionally containing a heteroatom selected from the group consisting of halogens, P, S, N and O; or a group CON(R.sup.2).sub.2, in which R.sup.2 groups, equal to or different from each other, are hydrogen or R.sup.1 groups which can be fused together to form one or more cycles, and A is a bivalent bridging group with the proviso that the Q groups cannot be simultaneously a group COOR.sup.1 or CON(R.sup.2).sub.2.

The present disclosure relates to a catalyst composition for polymerizing propylene and a method for producing polypropylene. The catalyst composition for polymerizing the propylene includes a modifying agent. The modifying agent is an ester compound having hydrophilic groups and hydrophobic groups. In the method for producing the polypropylene, a reverse microcellular structure is formed by the modifying agent during a propylene polymerization, in which the hydrophilic groups are inside the reverse microcellular structure, and the hydrophobic groups are outside the reverse microcellular structure, such that polar substances in a raw material are retained inside the reverse microcellular structure. Thus, poisoning of the catalyst is reduced. Besides, the modifying agent can maintain a valence state of titanium in an active site of the catalyst at positive trivalent, such that the propylene polymerization between the titanium and the monomer is facilitated, thereby enhancing an activity of the catalyst.

The present disclosure provides a heterogeneous Ziegler-Natta catalyst system to be used in the preparation of ultra-high molecular weight polymers (UHMWP). The system includes at least one procatalyst, at least one co-catalyst, at least one hydrocarbon medium and at least one external donor, wherein the ratio of elemental magnesium to elemental titanium to halide, in the procatalyst, is 1:1.3:3.7; the ratio of elemental aluminum, present in the co-catalyst to elemental titanium, present in the procatalyst, ranges between 6:1 and 12:1; and the ratio of elemental silicon, present in the external donor to elemental titanium, present in the procatalyst, ranges between 1:10 and 10:1. The present disclosure also provides a process for preparation of UHMWPE using the heterogeneous Ziegler-Natta catalyst system of the present disclosure.