A polyethylene powder, wherein, when a free induction decay curve obtained by the Carr-Purcell-Meiboom-Gill method in pulsed NMR is subjected to three-component approximation, the relaxation time T of each component and the abundance R of each component satisfy the following <requirement (1)> and <requirement (2)>:

<Requirement (1)>

An entanglement index at 180 C. determined by (formula I) is 12 to 25 ms:

(entanglement index)=T.sub.R.sub./(R.sub.+R.sub.)+T.sub.R.sub./(R.sub.+R.sub.) (formula I) T.sub.: relaxation time (ms) of low-mobility component R.sub.: abundance (%) of low-mobility component T.sub.: relaxation time (ms) of intermediate component R.sub.: abundance (%) of intermediate component
<Requirement (2)>

An intermediate component ratio at 180 C. determined by (formula II) is 0.25 to 0.5:

(intermediate component ratio)=R.sub./(R.sub.+R)(formula II).

The present invention presents an ethylene polymer, wherein the ethylene polymer has a weight average molecular weight (Mw) of 200,000 or more and 3,000,000 or less, a proportion of a component (130) with the lowest mobility of 40% or more and 60% or less, and a ratio / of a middle motion component () to a component () with the highest mobility of 1.0 or more and 4.0 or less when a three-component approximation of free induction decay at 130 C. measured by a solid echo method of pulse NMR is performed.

The present invention presents an ethylene polymer, wherein the ethylene polymer has a weight average molecular weight (Mw) of 200,000 or more and 3,000,000 or less, a proportion of a component (130) with the lowest mobility of 40% or more and 60% or less, and a ratio / of a middle motion component () to a component () with the highest mobility of 1.0 or more and 4.0 or less when a three-component approximation of free induction decay at 130 C. measured by a solid echo method of pulse NMR is performed.

The present invention provides an olefin coordination polymerization catalyst and use thereof. The composition of the raw materials of the olefin coordination polymerization catalyst comprises: a main catalyst and a cocatalyst, wherein a molar ratio of the transition metal halide in the main catalyst to the cocatalyst is 1:10-500; and the composition of the raw materials of the main catalyst comprises a magnesium compound, a transition metal halide, an alcohol having 2 to 15 carbon atoms, and a star-shaped organosiloxane compound in a molar ratio of 1:1-40:0.01-10:0.001-10; and the cocatalyst comprises an organoaluminum compound. The above olefin coordination polymerization catalyst is used as a catalyst for ethylene polymerization, propylene polymerization, and copolymerization of ethylene or propylene with an -olefin. The olefin polymerization catalyst of the present invention has good catalytic activity.

The present invention provides an olefin coordination polymerization catalyst and use thereof. The composition of the raw materials of the olefin coordination polymerization catalyst comprises: a main catalyst and a cocatalyst, wherein a molar ratio of the transition metal halide in the main catalyst to the cocatalyst is 1:10-500; and the composition of the raw materials of the main catalyst comprises a magnesium compound, a transition metal halide, an alcohol having 2 to 15 carbon atoms, and a star-shaped organosiloxane compound in a molar ratio of 1:1-40:0.01-10:0.001-10; and the cocatalyst comprises an organoaluminum compound. The above olefin coordination polymerization catalyst is used as a catalyst for ethylene polymerization, propylene polymerization, and copolymerization of ethylene or propylene with an -olefin. The olefin polymerization catalyst of the present invention has good catalytic activity.

The ultrahigh-molecular-weight polyethylene powder of the present invention is an ultrahigh-molecular-weight polyethylene powder having a viscosity-average molecular weight Mv of 1010.sup.4 or higher and 100010.sup.4 or lower, wherein viscosity-average molecular weight Mv(A) of a kneaded product obtained by kneading under specific kneading conditions, and the Mv satisfy the following relationship: {MvMv(A)}/Mv is 0.20 or less, and the ultrahigh-molecular-weight polyethylene powder contains an ultrahigh-molecular-weight polyethylene powder having a particle size of 212 m or larger, wherein the powder having a particle size of 212 m or larger has an average pore volume of 0.6 ml/g or larger and an average pore size of 0.3 m or larger.

The ultrahigh-molecular-weight polyethylene powder of the present invention is an ultrahigh-molecular-weight polyethylene powder having a viscosity-average molecular weight Mv of 1010.sup.4 or higher and 100010.sup.4 or lower, wherein viscosity-average molecular weight Mv(A) of a kneaded product obtained by kneading under specific kneading conditions, and the Mv satisfy the following relationship: {MvMv(A)}/Mv is 0.20 or less, and the ultrahigh-molecular-weight polyethylene powder contains an ultrahigh-molecular-weight polyethylene powder having a particle size of 212 m or larger, wherein the powder having a particle size of 212 m or larger has an average pore volume of 0.6 ml/g or larger and an average pore size of 0.3 m or larger.

The present invention relates to a procatalyst comprising the compound represented by formula A as an internal electron donor, Formula A wherein R is hydrogen or a methyl group, N is nitrogen atom; O is oxygen atom; and C is carbon atom. The present invention also relates to a process for preparing said polymerization procatalyst and to a polymerization catalyst system comprising said procatalyst, a co-catalyst and optionally an external electron donor. Furthermore, the present invention relates to a polyolefin obtainable by the process according to the present invention and to the use of the compound of formula A as in internal electron donor in catalysts for polymerization of olefins. ##STR00001##

The present invention relates to a procatalyst comprising the compound represented by formula A as an internal electron donor, Formula A wherein R is hydrogen or a methyl group, N is nitrogen atom; O is oxygen atom; and C is carbon atom. The present invention also relates to a process for preparing said polymerization procatalyst and to a polymerization catalyst system comprising said procatalyst, a co-catalyst and optionally an external electron donor. Furthermore, the present invention relates to a polyolefin obtainable by the process according to the present invention and to the use of the compound of formula A as in internal electron donor in catalysts for polymerization of olefins. ##STR00001##

The present invention relates to a procatalyst comprising the compound represented by formula A as an internal electron donor (Formula A), wherein R is hydrogen or a methyl group, N is nitrogen atom; O is oxygen atom; and C is carbon atom. The present invention also relates to a process for preparing said polymerization procatalyst and to a polymerization catalyst system comprising said procatalyst, a co-catalyst and optionally an external electron donor. Furthermore, the present invention relates to a polyolefin obtainable by the process according to the present invention and to the use of the compound of formula A as in internal electron donor in catalysts for polymerization of olefins. ##STR00001##