Disclosed is a method for preparing an EVA copolymer with a high ethylene content by solution polymerization under a low to a medium pressure. The method comprises the following steps: initiating with a free radical initiator(s), a copolymerization reaction between ethylene and vinyl acetate in a solvent in a reactor under a low to a medium pressure to obtain the EVA copolymer; and continuing to add ethylene during the reaction to maintain the low to medium pressure, wherein the low to medium pressure is 1-101 MPa, and a ratio of a mass of the vinyl acetate to a mass of the initially added ethylene is (1:1) to (1:20). The amount of ethylene incorporated in the EVA copolymer prepared according to the method is ≥ 50 wt%, and the EVA copolymer has properties equivalent to those of an EVA copolymer obtained by bulk polymerization at high temperature under high pressure.

Disclosed is a method for preparing an EVA copolymer with a high ethylene content by solution polymerization under a low to a medium pressure. The method comprises the following steps: initiating with a free radical initiator(s), a copolymerization reaction between ethylene and vinyl acetate in a solvent in a reactor under a low to a medium pressure to obtain the EVA copolymer; and continuing to add ethylene during the reaction to maintain the low to medium pressure, wherein the low to medium pressure is 1-101 MPa, and a ratio of a mass of the vinyl acetate to a mass of the initially added ethylene is (1:1) to (1:20). The amount of ethylene incorporated in the EVA copolymer prepared according to the method is ≥ 50 wt%, and the EVA copolymer has properties equivalent to those of an EVA copolymer obtained by bulk polymerization at high temperature under high pressure.

The present invention pertains to a method for producing a copolymer of ethylene and an allyl monomer having a polar group represented by general formula (1), or a copolymer of ethylene, an allyl monomer having a polar group represented by general formula (1), and other monomers, wherein the copolymer is produced in the presence of a boron compound having a boron-hydrogen bond or a boron-carbon bond (for example, a compound represented by general formula (2)) by using a metal complex represented by general formula (C1) as a polymerization catalyst (the symbols in the formulas are as described in the description). According to the present invention, a copolymer of ethylene and an allyl monomer can be efficiently produced with high catalytic activity, wherein the copolymer has a polar group and can be used in various applications. ##STR00001##

The present invention pertains to a method for producing a copolymer of ethylene and an allyl monomer having a polar group represented by general formula (1), or a copolymer of ethylene, an allyl monomer having a polar group represented by general formula (1), and other monomers, wherein the copolymer is produced in the presence of a boron compound having a boron-hydrogen bond or a boron-carbon bond (for example, a compound represented by general formula (2)) by using a metal complex represented by general formula (C1) as a polymerization catalyst (the symbols in the formulas are as described in the description). According to the present invention, a copolymer of ethylene and an allyl monomer can be efficiently produced with high catalytic activity, wherein the copolymer has a polar group and can be used in various applications. ##STR00001##

Blown films, especially monolayer blown films, with an improved property profile, the blown films comprising at least 95.0 wt% of a specific heterophasic propylene copolymer (TERHECO).

Blown films, especially monolayer blown films, with an improved property profile, the blown films comprising at least 95.0 wt% of a specific heterophasic propylene copolymer (TERHECO).

A multimodal polyethylene composition having a lower molecular weight (LMW) ethylene homo or copolymer component (A) and a higher molecular weight ethylene copolymer component (B); wherein the lower molecular weight component comprises: (ai) a first fraction which comprises an ethylene homo or copolymer of ethylene and one or more C3-10 alpha olefins; and (aii) a N second fraction which comprises a different ethylene homo or copolymer of ethylene and one or more C3-10 alpha olefins; wherein the multimodal polymer composition has a density of 930 kg/m.sup.3 or more (ISO1183), such as 938 to 955 kg/m.sup.3, an MFR2 (ISO1133 at 190° C. and 2.16 kg load) in the range of 0.05 to 10 g/10 min, and a flexural modulus of up to 800 MPa, such as 300 to 800 MPa (ISO 178:2010).

A multimodal polyethylene composition having a lower molecular weight (LMW) ethylene homo or copolymer component (A) and a higher molecular weight ethylene copolymer component (B); wherein the lower molecular weight component comprises: (ai) a first fraction which comprises an ethylene homo or copolymer of ethylene and one or more C3-10 alpha olefins; and (aii) a N second fraction which comprises a different ethylene homo or copolymer of ethylene and one or more C3-10 alpha olefins; wherein the multimodal polymer composition has a density of 930 kg/m.sup.3 or more (ISO1183), such as 938 to 955 kg/m.sup.3, an MFR2 (ISO1133 at 190° C. and 2.16 kg load) in the range of 0.05 to 10 g/10 min, and a flexural modulus of up to 800 MPa, such as 300 to 800 MPa (ISO 178:2010).

Provided is a collection of polymeric beads, wherein the beads comprise (i) 75 to 99% by weight, based on the weight of the bead, polymerized units of monofunctional vinyl monomer, and (ii) 1 to 25% by weight, based on the weight of the bead, polymerized units of multifunctional vinyl monomer; wherein, within each bead, the average concentration of moles of polymerized units of multifunctional vinyl monomer per cubic micrometer is MVAV; wherein, within each bead, T1000 is a sequence of 1,000 unique connected polymerized monomer units; wherein, within each T1000, MVSEQ is the weight percent polymerized units of multifunctional vinyl monomer, based on the weight of T1000; wherein MVRATIO=MVSEQ/MVAV; and wherein 90% or more of the beads by volume are uniform beads, wherein a uniform bead is a bead in which 90% or more of all T1000 sequences has MVRATIO of 1.5 or less.

Provided is a collection of polymeric beads, wherein the beads comprise (i) 75 to 99% by weight, based on the weight of the bead, polymerized units of monofunctional vinyl monomer, and (ii) 1 to 25% by weight, based on the weight of the bead, polymerized units of multifunctional vinyl monomer; wherein, within each bead, the average concentration of moles of polymerized units of multifunctional vinyl monomer per cubic micrometer is MVAV; wherein, within each bead, T1000 is a sequence of 1,000 unique connected polymerized monomer units; wherein, within each T1000, MVSEQ is the weight percent polymerized units of multifunctional vinyl monomer, based on the weight of T1000; wherein MVRATIO=MVSEQ/MVAV; and wherein 90% or more of the beads by volume are uniform beads, wherein a uniform bead is a bead in which 90% or more of all T1000 sequences has MVRATIO of 1.5 or less.