A method for producing a solid catalyst component (Aa) for ?-olefin polymerization, which includes: bringing components (A1) to (A4) into contact with one another in an inert solvent; and without washing the contact product with an inert solvent, aging the contact product by keeping for a holding time of 3 days or more and 180 days or less, regarding the time point that all of the components (A1) to (A4) first come into contact, as a starting point.

Provided are use of organosilane, in-reactor polyolefin alloy and preparation method thereof. The method of preparing an in-reactor polyolefin alloy comprises: conducting the first polymerization reaction of the first olefin monomer in the presence of a catalyst, and then charging the second olefin monomer into the polymerization reaction system to perform the second polymerization reaction, wherein the first olefin monomer is different from the second olefin monomer, wherein the first polymerization reaction and/or the second polymerization reaction are/is executed in the presence of organosilane represented by a general formula R.sup.1.sub.mSiX.sub.n(OR.sup.2).sub.k, wherein R.sup.1 is a C.sub.2-C.sub.20 alkyl; a terminal of R.sup.1 has an -olefin double bond, a norbornene group, a cycloalkene group, or a dicyclopentadiene group; X is a halogen element; R.sup.2 is a C.sub.1-C.sub.20 straight chain, a C.sub.1-C.sub.20 branched chain, or an isomerized alkyl group; m is an integer from 1-3; n is an integer from 1-3; k is an integer from 0-2; and m, n, and k satisfy the following condition: m+n+k=4. The in-reactor polyolefin alloy obtained by the above method has a high degree of crosslinking in a rubber phase, high impact resistance, and low tensile strength at break.

Provided are use of organosilane, in-reactor polyolefin alloy and preparation method thereof. The method of preparing an in-reactor polyolefin alloy comprises: conducting the first polymerization reaction of the first olefin monomer in the presence of a catalyst, and then charging the second olefin monomer into the polymerization reaction system to perform the second polymerization reaction, wherein the first olefin monomer is different from the second olefin monomer, wherein the first polymerization reaction and/or the second polymerization reaction are/is executed in the presence of organosilane represented by a general formula R.sup.1.sub.mSiX.sub.n(OR.sup.2).sub.k, wherein R.sup.1 is a C.sub.2-C.sub.20 alkyl; a terminal of R.sup.1 has an -olefin double bond, a norbornene group, a cycloalkene group, or a dicyclopentadiene group; X is a halogen element; R.sup.2 is a C.sub.1-C.sub.20 straight chain, a C.sub.1-C.sub.20 branched chain, or an isomerized alkyl group; m is an integer from 1-3; n is an integer from 1-3; k is an integer from 0-2; and m, n, and k satisfy the following condition: m+n+k=4. The in-reactor polyolefin alloy obtained by the above method has a high degree of crosslinking in a rubber phase, high impact resistance, and low tensile strength at break.

A solid catalyst component for olefin polymerization is produced by bringing a vinylsilane compound (d) into contact with a catalyst component, the catalyst component being a powdery solid component obtained by bringing a magnesium compound (a), a titanium halide compound (b), and an electron donor compound (c) into contact with each other, the electron donor compound (c) being one or more compounds that do not include a phthalic ester structure, and include one or more groups selected from an ester group, a carbonate group, and an ether group, the vinylsilane compound (d) being brought into contact with the catalyst component in a 0.1 to 15-fold molar quantity with respect to the molar quantity (on a titanium atom basis) of the titanium halide compound (b) included in the catalyst component.

This disclosure relates to rotomolded articles, having a wall structure, where the wall structure contains at least one layer containing an ethylene interpolymer product, or a blend containing an ethylene interpolymer product and an ethylene polymer, where the ethylene interpolymer product has a Dilution Index (Y.sub.d) greater than 0 and improved Environmental Stress Crack Resistance (ESCR). The ethylene interpolymer product has a melt index from about 0.5 to about 15 dg/minute, a density from about 0.930 to about 0.955 g/cm.sup.3, a polydispersity (M.sub.w/M.sub.n) from about 2 to about 6 and a CDBI.sub.50 from about 50% to about 98%. Further, the ethylene interpolymer products are a blend of at least two ethylene interpolymers; where one ethylene interpolymer is produced with a single-site catalyst formulation and at least one ethylene interpolymer is produced with a heterogeneous catalyst formulation.