Provided are an ethylene-vinyl acetate copolymer having a high degree of crosslinking by controlling a temperature difference in an autoclave reactor and an input ratio of an initiator during polymerization, even though a reduced amount of a crosslinking agent is used, and a preparation method thereof.

Provided are an ethylene-vinyl acetate copolymer having a high degree of crosslinking by controlling a temperature difference in an autoclave reactor and an input ratio of an initiator during polymerization, even though a reduced amount of a crosslinking agent is used, and a preparation method thereof.

The present invention is directed to a multimodal polyethylene copolymer comprising a first and a second copolymer of ethylene and at least two alpha-olefin comonomers. Such multimodal copolymers are highly suitable for conversion processes that require a high Draw Down Ratio, like the production of thin films. Such multimodal polyethylene copolymers provide a good impact strength in the sense of a high Dart drop impact strength (DDI) and good isotropy of the films produces thereof. The invention further presents final articles such as films made therefrom.

The present invention is directed to a multimodal polyethylene copolymer comprising a first and a second copolymer of ethylene and at least two alpha-olefin comonomers. Such multimodal copolymers are highly suitable for conversion processes that require a high Draw Down Ratio, like the production of thin films. Such multimodal polyethylene copolymers provide a good impact strength in the sense of a high Dart drop impact strength (DDI) and good isotropy of the films produces thereof. The invention further presents final articles such as films made therefrom.

A polyamide composition excellent in balance between fluidity during molding and, for example, surface appearance, bleed-out resistance, impact resistance and rigidity in the form of a molded article, and also relates to a polyamide composition a polyamide (A), an ethylene/α-olefin copolymer (B) satisfying requirements (b-1) to (b-3), and 0.1 to 20.0 mass % of an ethylene/α-olefin copolymer (C) satisfying the requirements (c-1) to (c-5), provided that (A)+(B)+(C)=100 mass %.

A polyamide composition excellent in balance between fluidity during molding and, for example, surface appearance, bleed-out resistance, impact resistance and rigidity in the form of a molded article, and also relates to a polyamide composition a polyamide (A), an ethylene/α-olefin copolymer (B) satisfying requirements (b-1) to (b-3), and 0.1 to 20.0 mass % of an ethylene/α-olefin copolymer (C) satisfying the requirements (c-1) to (c-5), provided that (A)+(B)+(C)=100 mass %.

The purpose of the present invention is to obtain an ethylene⋅α-olefin⋅non-conjugated polyene copolymer that has a low permanent compression set at low temperatures, is flexible, and has an excellent balance of rubber elasticity at low temperatures and tensile strength at normal temperatures. This ethylene-based polymer is an ethylene⋅α-olefin⋅non-conjugated polyene copolymer that includes units derived from ethylene (A), units derived from an α-olefin (B) containing 4-20 carbon atoms, and units derived from a non-conjugated polyene (C) and satisfies (1)-(4). (1) The molar ratio of (A) to (B) is 40/60-90/10, (2) the contained amount of the units derived from (C) is 0.1-6.0 mol %, (3) ML.sub.(1+4)125° C. is 5-100, and (4) the B value is 1.20 or more.

The purpose of the present invention is to obtain an ethylene⋅α-olefin⋅non-conjugated polyene copolymer that has a low permanent compression set at low temperatures, is flexible, and has an excellent balance of rubber elasticity at low temperatures and tensile strength at normal temperatures. This ethylene-based polymer is an ethylene⋅α-olefin⋅non-conjugated polyene copolymer that includes units derived from ethylene (A), units derived from an α-olefin (B) containing 4-20 carbon atoms, and units derived from a non-conjugated polyene (C) and satisfies (1)-(4). (1) The molar ratio of (A) to (B) is 40/60-90/10, (2) the contained amount of the units derived from (C) is 0.1-6.0 mol %, (3) ML.sub.(1+4)125° C. is 5-100, and (4) the B value is 1.20 or more.

The present invention provides a crosslinked molded article having a lower compression set; and a method for producing a crosslinked molded article by injection molding, the method enabling shortening of one cycle in injection molding, the method being suitable for obtaining a crosslinked molded article having a lower compression set. The present invention relates to a method for producing a crosslinked molded article, comprising melt-kneading a polymer composition containing a polymer having a terminal double bond, a hydrosilyl group-containing compound (Y) having at least two hydrosilyl groups per molecule, a platinum-based catalyst (Z) for hydrosilicon crosslinking, and a reaction inhibitor (D), subjecting the polymer composition to injection molding in a mold, performing primary crosslinking in the mold, removing the primary-crosslinked molded article from the mold, and then performing secondary crosslinking in a heat medium.

The present invention provides a crosslinked molded article having a lower compression set; and a method for producing a crosslinked molded article by injection molding, the method enabling shortening of one cycle in injection molding, the method being suitable for obtaining a crosslinked molded article having a lower compression set. The present invention relates to a method for producing a crosslinked molded article, comprising melt-kneading a polymer composition containing a polymer having a terminal double bond, a hydrosilyl group-containing compound (Y) having at least two hydrosilyl groups per molecule, a platinum-based catalyst (Z) for hydrosilicon crosslinking, and a reaction inhibitor (D), subjecting the polymer composition to injection molding in a mold, performing primary crosslinking in the mold, removing the primary-crosslinked molded article from the mold, and then performing secondary crosslinking in a heat medium.