A propylene copolymer, a preparation method therefor, and an application thereof are provided. The copolymer forms a cross-linked network by means of a reaction between a furan-containing propylene copolymer and a small molecule of a coupling agent, thereby achieving a chemical bond connection between a polypropylene resin phase and an ethylene-propylene copolymer elastomer phase, fundamentally strengthening the force between the two phases, and improving the mechanical properties of a material. Meanwhile, the copolymer can achieve the decrosslinking of a material during melt processing such that the material has thermoplasticity, and after cooling, it can be crosslinked again to produce network structure.

A propylene copolymer, a preparation method therefor, and an application thereof are provided. The copolymer forms a cross-linked network by means of a reaction between a furan-containing propylene copolymer and a small molecule of a coupling agent, thereby achieving a chemical bond connection between a polypropylene resin phase and an ethylene-propylene copolymer elastomer phase, fundamentally strengthening the force between the two phases, and improving the mechanical properties of a material. Meanwhile, the copolymer can achieve the decrosslinking of a material during melt processing such that the material has thermoplasticity, and after cooling, it can be crosslinked again to produce network structure.

Provided are a method of preparing a vinyl chloride-based polymer composite, a vinyl chloride-based polymer composite, and a vinyl chloride-based polymer composite composition including the composite, the method including: a first step of performing bulk polymerization of vinyl chloride-based monomers; and a second step of recovering unreacted vinyl chloride-based monomers after the completion of the bulk polymerization and obtaining a vinyl chloride-based polymer composite, wherein polyvinyl alcohol is added in at least one step of the first step and the second step, and the polyvinyl alcohol is added in an amount of 0.003 parts by weight to 0.500 parts by weight based on a total of 100 parts by weight of the vinyl chloride-based monomers.

Provided are a method of preparing a vinyl chloride-based polymer composite, a vinyl chloride-based polymer composite, and a vinyl chloride-based polymer composite composition including the composite, the method including: a first step of performing bulk polymerization of vinyl chloride-based monomers; and a second step of recovering unreacted vinyl chloride-based monomers after the completion of the bulk polymerization and obtaining a vinyl chloride-based polymer composite, wherein polyvinyl alcohol is added in at least one step of the first step and the second step, and the polyvinyl alcohol is added in an amount of 0.003 parts by weight to 0.500 parts by weight based on a total of 100 parts by weight of the vinyl chloride-based monomers.

A process for producing an ethylene copolymer, the process including: (a) contacting ethylene with at least one polar comonomer in the presence of at least one modifier and at least one free radical initiator in a tubular reactor under polymerization conditions including a pressure of from 225 to 270 MPa; (b) injecting the at least one free radical initiator into the reactor at a plurality of reaction zones spaced along the length of the reactor, wherein each reaction zone comprises an inlet and an outlet; (c) maintaining the temperature at the inlet of each reaction zone at 150° C. or less, and the temperature at the outlet of each reaction zone is at least 177° C.; (d) controlling the modifier flow at a rate of from 0.02 to 0.986 wt % of the copolymer; and (e) recovering the ethylene copolymer from the tubular reactor, is provided.

A process for producing an ethylene copolymer, the process including: (a) contacting ethylene with at least one polar comonomer in the presence of at least one modifier and at least one free radical initiator in a tubular reactor under polymerization conditions including a pressure of from 225 to 270 MPa; (b) injecting the at least one free radical initiator into the reactor at a plurality of reaction zones spaced along the length of the reactor, wherein each reaction zone comprises an inlet and an outlet; (c) maintaining the temperature at the inlet of each reaction zone at 150° C. or less, and the temperature at the outlet of each reaction zone is at least 177° C.; (d) controlling the modifier flow at a rate of from 0.02 to 0.986 wt % of the copolymer; and (e) recovering the ethylene copolymer from the tubular reactor, is provided.

The dewaxing aid of the present invention is a dewaxing aid including an ethylene-α-olefin copolymer (A) having a molar ratio [(a)/(b)] of (a) ethylene and (b) an α-olefin having 3 or more and 12 or less carbon atoms of 93/7 to 75/25, and having a weight average molecular weight of 10,000 to 500,000. According to the present invention, a dewaxing aid that is excellent in improving filterability can be provided.

The dewaxing aid of the present invention is a dewaxing aid including an ethylene-α-olefin copolymer (A) having a molar ratio [(a)/(b)] of (a) ethylene and (b) an α-olefin having 3 or more and 12 or less carbon atoms of 93/7 to 75/25, and having a weight average molecular weight of 10,000 to 500,000. According to the present invention, a dewaxing aid that is excellent in improving filterability can be provided.

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.