Method of production of ethylene-based polymer particles and stretch-molded article obtained from ethylene-based polymer particles

A method of production of ethylene-based polymer particles;

• wherein the method comprises the step of:
• homopolymerizing ethylene or copolymerizing ethylene and a linear or branched α-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst comprising:
• (A) fine particles having an average particle diameter greater than or equal to 1 nm and less than or equal to 300 nm obtained at least by the following two steps:
• (Step 1) causing contact between a metal halide and an alcohol in a hydrocarbon solvent wherein the alcohol is a combination of two types of alcohols selected from alcohols having 1 to 25 carbon atoms and difference in carbon number of the two types of alcohols is greater than or equal to 4;
• (Step 2) causing contact between a component obtained by (Step 1) and an organoaluminum compound and/or an organoaluminumoxy compound;
• and
• (B) a transition metal compound represented in following General Formula (I) or (II):
• wherein in Formula (I), M is a transition metal atom of Group 4 or 5 in the periodic table;
• m is an integer ranging from 1 to 4;
• R1 to R5 are the same or different and are a hydrogen atom, halogen atom, hydrocarbon group, heterocyclic compound residue, oxygen-containing group, nitrogen-containing group, boron-containing group, sulfur-containing group, phosphorous-containing group, silicon-containing group, germanium-containing group, or tin-containing group, wherein a ring is optionally formed by bonding together of at least 2 such groups;
• R6 is selected from the group consisting of a hydrogen atom, hydrocarbon groups having 1 to 4 carbon atoms and composed of only primary or secondary carbon atoms, aliphatic hydrocarbon groups having at least 4 carbon atoms, aryl group-substituted alkyl groups, monocyclic or bicyclic alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and halogen atoms;
• n is a number satisfying valence number of M;
• X is a hydrogen atom, halogen atom, hydrocarbon group, oxygen-containing group, sulfur-containing group, nitrogen-containing group, boron-containing group, aluminum-containing group, phosphorous-containing group, halogen-containing group, heterocyclic compound residue, silicon-containing group, germanium-containing group, or tin-containing group;
• wherein multiple groups indicated by X may be the same or different when n is greater than or equal to 2;
• and optionally multiple groups indicated by X form a ring by mutual bonding
• wherein in Formula (II), M is titanium, zirconium, or hafnium;
• R11 to R18 may be the same or different and are a hydrogen atom, halogen atom, hydrocarbon group, heterocyclic compound residue, oxygen-containing group, nitrogen-containing group, boron-containing group, sulfur-containing group, phosphorous-containing group, silicon-containing group, germanium-containing group, or tin-containing group, wherein two or more adjacent groups may be optionally bonded together to form a ring;
• X1 and X2 are the same or different and are a hydrocarbon group, oxygen-containing group, sulfur-containing group, silicon-containing group, hydrogen atom, or halogen atom;
• and
• Y is a divalent hydrocarbon group, divalent halogenated hydrocarbon group, divalent silicon-containing group, divalent germanium-containing group, divalent tin-containing group, —O—, —CO—, —S—, —SO—, —SO2—, —Ge—, —Sn—, —NR—, —P(R)—, —P(O)(R)—, —BR—, or —AlR— wherein R is the same or different and is a hydrogen atom, halogen atom, hydrocarbon group, halogenated hydrocarbon group, or alkoxy group;
• and
• wherein an intrinsic viscosity [η] of the ethylene-based polymer particles, measured in decalin at 135° C., is from 5 to 50 dL/g.