The invention provides an ethylene-based polymer comprising the following properties: a) weight fraction (w) of molecular weight above 5*10.sup.6 g/mol, w>A−B*I2, where A=0.4 wt %, and B is 0.02 wt %/(dg/min), and w<C−B*I.sub.2%, where C=0.9 wt %; and b) G′>D−E*log(I2), where D=162 Pa and E=52 Pa/log(dg/min).

The present invention relates to the use of at least one peroxide selected from the group consisting of hemiperoxyacetals, alone or in combination with one or more distinct additional peroxides, for the radical polymerization or copolymerization of ethylene under high pressure.

The invention also concerns a process for preparing polyethylene, comprising a step of radical polymerization or copolymerization of ethylene under high pressure in the presence of at least one peroxide selected from the group consisting of hemiperoxyacetals, alone or in combination with one or more distinct additional peroxides.

The present invention likewise pertains to a composition comprising ethylene, at least one peroxide selected from the group consisting of hemiperoxyacetals, and optionally one or more additional peroxides distinct from hemiperoxyacetals.

The present invention relates to the use of at least one peroxide selected from the group consisting of hemiperoxyacetals, alone or in combination with one or more distinct additional peroxides, for the radical polymerization or copolymerization of ethylene under high pressure.

The invention also concerns a process for preparing polyethylene, comprising a step of radical polymerization or copolymerization of ethylene under high pressure in the presence of at least one peroxide selected from the group consisting of hemiperoxyacetals, alone or in combination with one or more distinct additional peroxides.

The present invention likewise pertains to a composition comprising ethylene, at least one peroxide selected from the group consisting of hemiperoxyacetals, and optionally one or more additional peroxides distinct from hemiperoxyacetals.

The present invention relates to a method for producing a copolymer, a copolymer produced therefrom, and a thermoplastic resin composition including the same, the method including step (S10) for adding aromatic vinyl-based monomers and vinyl cyan-based monomers to perform polymerization in the presence of polymerization initiators, wherein the polymerization initiators includes at least two different kinds of polymerization initiators, and part or all of the aromatic vinyl-based monomers are continuously divisionally added during the polymerization in step (S10).

The present invention relates to a method for producing a copolymer, a copolymer produced therefrom, and a thermoplastic resin composition including the same, the method including step (S10) for adding aromatic vinyl-based monomers and vinyl cyan-based monomers to perform polymerization in the presence of polymerization initiators, wherein the polymerization initiators includes at least two different kinds of polymerization initiators, and part or all of the aromatic vinyl-based monomers are continuously divisionally added during the polymerization in step (S10).

Provided is a method of preparing a copolymer which includes 1) initiating polymerization by batch-adding an aromatic vinyl-based monomer and a vinyl cyan-based monomer to a reactor; and 2) performing polymerization by continuously adding an aromatic vinyl-based monomer to the reactor at a predetermined rate after the initiation of polymerization, wherein the continuous addition of the aromatic vinyl-based monomer is initiated when a polymerization conversion rate is 10% or less and terminated when a polymerization conversion rate is between 80 and 90%, and step 2) includes a first temperature phase and a second temperature phase, each of which maintains a constant temperature, wherein a temperature of the second temperature phase is higher than that of the first temperature phase, and thereby a copolymer with a small standard deviation for a vinyl cyan-based unit composition and excellent transparency may be prepared.

Provided is a method of preparing a copolymer which includes 1) initiating polymerization by batch-adding an aromatic vinyl-based monomer and a vinyl cyan-based monomer to a reactor; and 2) performing polymerization by continuously adding an aromatic vinyl-based monomer to the reactor at a predetermined rate after the initiation of polymerization, wherein the continuous addition of the aromatic vinyl-based monomer is initiated when a polymerization conversion rate is 10% or less and terminated when a polymerization conversion rate is between 80 and 90%, and step 2) includes a first temperature phase and a second temperature phase, each of which maintains a constant temperature, wherein a temperature of the second temperature phase is higher than that of the first temperature phase, and thereby a copolymer with a small standard deviation for a vinyl cyan-based unit composition and excellent transparency may be prepared.

The present invention relates to a method for producing a copolymer, the method for producing a copolymer including: step (S10) for adding aromatic vinyl-based monomers substituted with alkyl groups and vinyl cyan-based monomers to perform polymerization in the presence of a polymerization initiator, wherein the vinyl cyan-based monomers are collectively added before initiation of the polymerization in step (S10), monomer droplets are continuously divisionally added during the polymerization in step (S10), and the monomer droplets contain part or all of the aromatic vinyl-based monomers substituted with alkyl groups, and relates to a copolymer produced therefrom, and a thermoplastic resin composition including the same.

The present invention relates to a method for producing a copolymer, the method for producing a copolymer including: step (S10) for adding aromatic vinyl-based monomers substituted with alkyl groups and vinyl cyan-based monomers to perform polymerization in the presence of a polymerization initiator, wherein the vinyl cyan-based monomers are collectively added before initiation of the polymerization in step (S10), monomer droplets are continuously divisionally added during the polymerization in step (S10), and the monomer droplets contain part or all of the aromatic vinyl-based monomers substituted with alkyl groups, and relates to a copolymer produced therefrom, and a thermoplastic resin composition including the same.

A copolymer may include ethylene and vinyl acetate, in which the ethylene is at least partially obtained from a renewable source of carbon. Embodiments may also be directed to curable polymer compositions, expandable polymer compositions, articles, cured articles, and expanded articles formed from or including such copolymers of ethylene and vinyl acetate, in which the ethylene is at least partially obtained from a renewable source of carbon. A process for producing an ethylene vinyl acetate copolymer may include fermenting a renewable source of carbon to produce ethanol; dehydrating the ethanol, wherein the ethanol is dehydrated to produce ethylene; and polymerizing ethylene and vinyl acetate to produce the ethylene vinyl acetate copolymer.