JP5683840B2 - Ethylene polymer for foam molding, resin composition for foam molding, and foam obtained therefrom - Google Patents

Description

  The present invention relates to an ethylene-based polymer for foam molding excellent in extrusion characteristics, a resin composition for foam molding containing the polymer, and a foam obtained therefrom.

  Ethylene polymers are molded by various molding methods and are used for various purposes. Depending on these molding methods and applications, the properties required for the ethylene-based polymer also differ. For example, in order to obtain a lightweight foam with excellent shock absorption and heat insulation properties by foam molding, the foam has a high foaming ratio and a good foamed state (there are few broken bubbles and coarse bubbles, uniform bubbles Many) is necessary. In order to obtain a high foaming ratio and a good foamed state, it is necessary to retain bubbles in the molten state, and an ethylene polymer having a high melt tension must be selected. Increasing the molecular weight can be cited as a means for increasing the melt tension. However, if the molecular weight is excessively increased, the melt shear viscosity of the ethylene polymer increases and the extrusion characteristics deteriorate. For this reason, in order to obtain a foam having a high foaming ratio and a good foamed state, an ethylene polymer having a high melt tension relative to the melt shear viscosity must be selected.

  Various methods for producing foams from ethylene polymers are known. For example, gases such as butane, hexane, chlorofluorocarbon, and carbon dioxide gas or those that become gas when heated are dispersed in the ethylene polymer. Alternatively, a method of melting and non-crosslinking foaming by extrusion foaming or bead foaming has been put into practical use. Non-crosslinked foams produced by these methods are excellent in shock absorption and waterproofness and are used in various buffer materials. On the other hand, a method in which a heat decomposable foaming agent is mixed with an ethylene polymer and molded, and then heated while irradiating ionizing radiation to cause crosslinking and foaming. There is a method in which an organic peroxide having a lower decomposition temperature is mixed and molded, and then heated to first decompose the organic peroxide, and then the foaming agent is decomposed to crosslink and foam. Crosslinked foams produced by these methods are superior in durability compared to non-crosslinked foams, and are used in building materials such as waterproof materials and various heat insulating materials.

  In these foam moldings, high-pressure low-density polyethylene is mainly used. Since the high-pressure low-density polyethylene has a complicated long-chain branched structure, the melt tension is larger for the melt shear viscosity than the linear ethylene polymer. For this reason, the high pressure method low density polyethylene is excellent in extrusion characteristics, and the obtained foam has a high expansion ratio and is excellent in a foamed state. However, the high-pressure low-density polyethylene has a complicated long chain branch structure and many short chain branches (mainly methyl groups and ethyl groups), and therefore is inferior in mechanical strength such as tensile strength and impact strength.

  Ethylene polymers obtained using Ziegler-Natta catalysts are excellent in mechanical strength such as tensile strength and impact strength, but their melt tension is small relative to the shear viscosity. It is difficult to obtain a good foamed state. In addition, since α-olefins are introduced non-uniformly in the molecular chain, the cross-linking foam molding has a variation in cross-linking density and forms non-uniform bubbles. Furthermore, since the shear viscosity at the time of melting is high, there is a problem that extrusion characteristics are poor.

  The ethylene polymer obtained by using the metallocene catalyst has a cross-linked foam molding because α-olefin is uniformly introduced into the molecular chain as compared with the ethylene polymer obtained by using the Ziegler-Natta catalyst. The cross-linking density variation in is improved. However, the shear viscosity at the time of melting is rather high, and the extrusion characteristics at the time of molding are further deteriorated. Further, since the melt tension is still small, it is difficult to increase the expansion ratio in non-crosslinking foam molding, and the foamed state is inferior.

  In order to solve such problems, various ethylene polymers in which a long-chain branched structure is introduced into a polymer by a metallocene catalyst and the melt tension is improved with respect to the shear viscosity are disclosed. For example, Patent Document 1 proposes a composition of an ethylene polymer obtained using a metallocene catalyst and a high-pressure low-density polyethylene. However, when the content of the high-pressure method low-density polyethylene is large, it is expected that the mechanical strength such as tensile strength and impact strength is inferior. When the content of the high-pressure method low-density polyethylene is small, the melt tension is sufficiently improved. Therefore, it is expected that the expansion ratio cannot be increased and the foamed state is inferior.

Patent Document 2 discloses an ethylene polymer obtained by solution polymerization in the presence of a catalyst composed of ethylenebis (indenyl) hafnium dichloride and methylalumoxane. Patent Document 3 discloses an ethylene polymer obtained by gas phase polymerization in the presence of a catalyst comprising ethylenebis (indenyl) zirconium dichloride supported on silica and methylalumoxane. Patent Document 4 discloses an ethylene polymer obtained by solution polymerization in the presence of a geometrically constrained catalyst. Patent Document 5 discloses an ethylene polymer obtained by gas phase polymerization in the presence of a catalyst comprising a racemic and meso form of Me ₂ Si (2-Me-Ind) ₂ supported on silica and methylalumoxane. It is disclosed. Although there is a description that these ethylene polymers are improved in melt tension as compared with linear ethylene polymers having no long-chain branches, the melt tension is lower than that in high-pressure low-density polyethylene. Therefore, it is expected that it is difficult to obtain a high expansion ratio and a good foamed state.

  Patent Document 6 discloses an ethylene polymer obtained by copolymerization of a macromonomer and ethylene in the presence of diphenylmethylene (1-cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride. An uncrosslinked foamed molded article is disclosed. There is a description that this ethylene polymer is improved in melt tension by introduction of long chain branching, has a high expansion ratio, and is excellent in a foamed state. However, since this ethylene polymer is not copolymerized with a low molecular weight α-olefin represented by 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and the like, It is expected that the temperature range in which foam molding can be performed is extremely narrow due to the poor mechanical strength and flexibility of the foam molded article and the high melting point.

  Patent Document 7 discloses an ethylene polymer in which zero shear viscosity and weight average molecular weight satisfy a specific relationship, and a ratio between melt tension and shear viscosity satisfies a specific relationship. Since this ethylene polymer has a high melt tension relative to the shear viscosity, and the elongational viscosity exhibits strain rate curability by satisfying a specific relationship between the zero shear viscosity and the weight average molecular weight, the resulting foam is foamed. The magnification is high, the foamed state is excellent, and the mechanical strength is expected to be superior to that of the high-pressure method low-density polyethylene. However, when a foam obtained from an ethylene polymer is used as a buffer protective material or the like, further improvement in mechanical strength is desired.

  As described above, it has been difficult to efficiently obtain a foam made of an ethylene-based resin having a high expansion ratio, an excellent foamed state, and particularly excellent mechanical strength from the conventional known technology.

JP 7-26079 A JP-A-2-276807 JP-A-4-213309 International Publication No. 93/08221 Pamphlet JP-A-8-311260 JP 2006-96910 A JP 2006-233206 A

  The present invention relates to an ethylene-based polymer for foam molding excellent in extrusion characteristics, a resin composition for foam molding containing the polymer, and a high foaming ratio composed thereof, excellent in a foamed state, and particularly excellent in mechanical strength. The object is to provide a foam.

  As a result of intensive investigations to solve the above problems, the inventors of the present invention have a high foaming ratio and an excellent foamed state by foam molding a specific ethylene polymer or a resin composition containing the polymer. And it discovered that the foam which is especially excellent in mechanical strength was obtained, and came to complete this invention.

That is, the present invention includes the following matters.
[1] Foam molding, which is an ethylene homopolymer or a copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms, and simultaneously satisfies the following requirements (I) to (VI) Ethylene-based polymer.
(I) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is in the range of 0.1 to 10 g / 10 min.
(II) The density (d) is in the range of 875 to 970 kg / m ³ .
(III) Ratio [MT / η ^* (1) of melt tension [MT (g)] at 190 ° C. and shear viscosity [η ^* (1.0) (P)] at 200 ° C. and an angular velocity of 1.0 rad / sec. 0.0)] is in the range of 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ g / P.
(IV) The sum [(A + B) (/ 1000C)] of the number of methyl branches A (/ 1000C) and the number of ethyl branches B (/ 1000C) per 1000 carbon atoms measured by ¹³ C-NMR is 1.8. It is as follows.
(V) Zero shear viscosity η ₀ (P) at 200 ° C. and a weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) satisfy the following relational expression.
0.10 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 60 × 10 ⁻³¹ × Mw ^6.8
(VI) The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is in the range of 1.0 × 10 ^{4.20 to} 1.0 × 10 ^4.60 .

[2] The ethylene-based polymer for foam molding according to [1], further satisfying the following requirements (VII) and (VIII):
(VII) The intrinsic viscosity [η] (dl / g) measured in decalin at 135 ° C. and the weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) Eq-1] is satisfied.
0.80 × 10 ⁻⁴ × Mw ^0.776 ≦ [η] ≦ 1.65 × 10 ⁻⁴ × Mw ^0.776 [Eq-1]
(VIII) Shear viscosity [η ^* (100)] (P) at 200 ° C. and angular velocity 100 rad / sec, and Shear viscosity [η ^* (1.0)] (P) at 200 ° C. and angular velocity 1.0 rad / sec The ratio [η ^* (100) / η ^* (1.0)] is in the range of 0.04 to 0.40.

[3] A foam molding resin composition comprising the foam molding ethylene polymer according to [1] or [2] and a thermoplastic resin other than the foam molding ethylene polymer.
[4] An ethylene polymer for foam molding as described in [1] or [2], or a foam obtained from the resin composition for foam molding as described in [3].

  According to the present invention, an ethylene polymer for foam molding having excellent extrusion characteristics can be obtained, and the foam ratio is obtained by foam molding the foam molding ethylene polymer or the foam molding resin composition containing the polymer. , A foam having excellent foamed state and particularly excellent mechanical strength can be obtained.

  Hereinafter, an ethylene polymer for foam molding of the present invention (hereinafter also simply referred to as “ethylene polymer”), a resin composition for foam molding (hereinafter also simply referred to as “resin composition”), and a foam obtained therefrom. The body will be specifically described.

[Ethylene polymer for foam molding]
The ethylene-based polymer for foam molding of the present invention is an ethylene homopolymer or a copolymer obtained from ethylene and an α-olefin having 4 to 20 carbon atoms, and satisfies the following requirements (I) to (VI): It is characterized by satisfying at the same time.
(I) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is in the range of 0.1 to 10 g / 10 min.
(II) The density (d) is in the range of 875 to 970 kg / m ³ .
(III) Ratio [MT / η ^* (1) of melt tension [MT (g)] at 190 ° C. and shear viscosity [η ^* (1.0) (P)] at 200 ° C. and an angular velocity of 1.0 rad / sec. 0.0)] is in the range of 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ g / P.
(IV) The sum [(A + B) (/ 1000C)] of the number of methyl branches A (/ 1000C) and the number of ethyl branches B (/ 1000C) per 1000 carbon atoms measured by ¹³ C-NMR is 1.8. It is as follows.

(V) Zero shear viscosity η ₀ (P) at 200 ° C. and a weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) satisfy the following relational expression.
0.10 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 60 × 10 ⁻³¹ × Mw ^6.8
(VI) The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is in the range of 1.0 × 10 ^{4.20 to} 1.0 × 10 ^4.60 .

  The ethylene-based polymer for foam molding of the present invention contains at least one polymer selected from an ethylene homopolymer and an ethylene / C4-C20 α-olefin copolymer.

  Examples of the α-olefin having 4 to 20 carbon atoms include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1- Examples include hexadecene, 1-octadecene, and 1-eicocene. Of these, α-olefins having 4 to 10 carbon atoms such as 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene are preferable, and 1-hexene, 4-methyl-1- C6-C10 alpha olefins, such as pentene, 1-octene and 1-decene, are more preferred. One α-olefin may be used alone, or two or more α-olefins may be used in combination. When 1-butene is used as the α-olefin, an α-olefin having 6 to 10 carbon atoms is also used.

The ethylene-based polymer for foam molding of the present invention may contain structural units composed of the following copolymer monomers in addition to the α-olefin, as long as the above requirements (I) to (VI) are satisfied.
Specifically, cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene and 2-methyl-1,4: 5,8-dimethano-1,2,3,4,4a, 5 Cyclic olefins such as 8,8a-octahydronaphthalene; styrene; vinylcyclohexane; various dienes; and acrylic acid, methacrylic acid, fumaric acid, maleic anhydride, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate and Examples include polar monomers such as methacrylic acid. These copolymerizable monomers may be used individually by 1 type, and may be used in combination of 2 or more type.

Next, requirements (I) to (VI) will be described.
(I) The melt flow rate (MFR) is in the range of 0.1 to 10 g / 10 minutes, preferably 0.5 to 5.0 g / 10 minutes, more preferably 0.5 to 2.5 g / 10 minutes.

  When the melt flow rate (MFR) is 0.1 g / 10 min or more, the shear viscosity of the ethylene polymer is not too high, and the extrusion characteristics are good. When the melt flow rate (MFR) is 10 g / 10 min or less, the obtained foam has good mechanical strength, and the shear viscosity of the ethylene polymer is not too low, and the foam moldability is good. That is, when the melt flow rate (MFR) is in the above range, the shear stability of the ethylene-based polymer is good, and thus the extrusion characteristics and foam moldability are excellent. The resulting foam has excellent mechanical strength, and Excellent foam moldability.

  The melt flow rate (MFR) strongly depends on the molecular weight of the ethylene polymer. The smaller the melt flow rate (MFR), the larger the molecular weight, and the higher the melt flow rate (MFR), the smaller the molecular weight. Further, it is known that the molecular weight of an ethylene polymer is determined by the composition ratio (hydrogen / ethylene) of hydrogen and ethylene in the polymerization reaction system (for example, “Katao Soga et al.,“ Catalytic Olefin Polymerization ”). Kodansha Scientific, 1990, p. 376). For this reason, the melt flow rate (MFR) of the ethylene polymer can be increased or decreased by adjusting the hydrogen / ethylene ratio.

(II) The density (d) is in the range of 875 to 970 kg / m ³ , preferably 900 to 955 kg / m ³ , more preferably 900 to 940 kg / m ³ .
Specifically, if the density (d) is 875 kg / m ³ or more, the foam obtained from the ethylene-based polymer has small shrinkage and uniform bubbles, and if it is 970 kg / m ³ or less, molding in foam molding is possible. The wide temperature range is relatively wide.

  The density depends on the α-olefin content in the ethylene polymer. The smaller the α-olefin content, the higher the density, and the higher the α-olefin content, the lower the density. Since the α-olefin content in the ethylene-based polymer is determined by the amount of ethylene and α-olefin supplied into the polymerization system (for example, Walter Kaminsky, Makromol. Chem. 193, p. 606 (1992)). By adjusting the supply amount of ethylene and α-olefin, an ethylene polymer having a density in the above range can be produced.

(III) Ratio [MT / η ^* (1) of melt tension [MT (g)] at 190 ° C. and shear viscosity [η ^* (1.0) (P)] at 200 ° C. and an angular velocity of 1.0 rad / sec. .0) (g / P)] is 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ , preferably 1.50 × 10 ^{−4 to} 5.00 × 10 ⁻⁴ , more preferably 2.00. × is in the range of 10 ^-4 ~5.00 × 10 ^-4.

It is known that when the melt tension of the ethylene-based polymer is large, a foam having a high foaming ratio and good quality having closed cells can be obtained (for example, JP-A 2006-199872). On the other hand, if the molecular weight is increased in order to increase the melt tension, the shear viscosity of the ethylene polymer increases, and the extrusion characteristics deteriorate. In order to increase the melt tension without increasing the shear viscosity too much, the lower limit of [MT / η ^* (1.0)] needs to be 1.00 × 10 ⁻⁴ (g / P) or more. When [MT / η ^* (1.0)] is in the range of 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ (g / P), the extrusion characteristics of the ethylene polymer are good, It is also possible to increase the foaming ratio of the obtained foam, and a good foamed state having uniform bubbles can be obtained.

[MT / η ^* (1.0)] depends on the long chain branching content of the ethylene polymer. The larger the long chain branching content, the larger [MT / η ^* (1.0)]. The smaller the branch content, the smaller [MT / η ^* (1.0)].

  Long chain branching is defined as a branched structure having a length equal to or greater than the molecular weight (Me) between entanglement points contained in an ethylene polymer, and the introduction of long chain branching results in the melt property and molding processability of the ethylene polymer being It is known to change significantly (for example, Kazuo Matsuura et al., “Polyethylene Technology Reader”, Industrial Research Committee, 2001, p. 32 and p. 36).

  The ethylene-based polymer of the present invention is ethylene in the presence of a catalyst for producing an ethylene-based polymer containing a specific crosslinked metallocene compound (component (A) and component (B)) and a component (C) described later, or It can be produced by polymerizing ethylene and an α-olefin having 4 to 20 carbon atoms.

  As a mechanism for producing the ethylene polymer of the present invention, the present inventors have prepared an ethylene polymer containing component (A), component (C) and, if necessary, a solid carrier (component (S)). In the presence of a catalyst, ethylene or ethylene and an α-olefin having 4 to 20 carbon atoms are polymerized, preferably ethylene and an α-olefin having 4 to 10 carbon atoms are polymerized, more preferably ethylene and carbon. By polymerizing an α-olefin having a number of 6 to 10, a polymer (macromonomer) having a terminal vinyl having a number average molecular weight (Mn) of, for example, 4000 to 20000, preferably 4000 to 15000, is generated. And the polymerization of ethylene and the α-olefin using a catalyst for producing an ethylene-based polymer containing the component (B), the component (C) and, if necessary, the component (S). Black By a monomer competitively (co) polymerized, long chain branching in the ethylene polymer is considered to be generated.

The long chain branching content in the ethylene polymer of the present invention depends on the composition ratio ([macromonomer] / [ethylene]) of the macromonomer and ethylene in the polymerization system, and [macromonomer] / [ethylene ] Is higher, the long chain branching content in the ethylene polymer is increased. Since [macromonomer] / [ethylene] can be increased by increasing the ratio ([A] / [A + B]) of the component (A) in the catalyst for ethylene polymer production, [A] / [A + B] By increasing or decreasing, an ethylene polymer having [MT / η ^* (1.0)] in the above range can be produced.

(IV) The sum [(A + B) (/ 1000C)] of the number of methyl branches [A (/ 1000C)] and the number of ethyl branches [B (/ 1000C)] measured by ¹³ C-NMR is 1.8 or less, Preferably it is 1.3 or less, More preferably, it is 0.8 or less, Most preferably, it is 0.5 or less.

  The number of methyl branches and the number of ethyl branches defined in the present invention are defined by the number per 1000 carbon atoms constituting the polymer chain. When short chain branches such as methyl branch and ethyl branch are present in the ethylene polymer, the short chain branch is incorporated into the crystal and the interplanar spacing of the crystal widens, which may reduce the mechanical strength of the resin. It is known (for example, supervised by Zenjiro Osawa et al., “Technology for polymer life prediction and extension of life”, NTS Corporation, 2002, p. 481). Therefore, when the sum of the number of methyl branches and the number of ethyl branches (A + B) is 1.8 or less, the mechanical strength of the ethylene polymer is good.

  The number of methyl branches and the number of ethyl branches in the ethylene polymer strongly depends on the polymerization method of the ethylene polymer, and the ethylene polymer obtained by high-pressure radical polymerization is coordinated using a Ziegler-Natta catalyst. The number of methyl branches and the number of ethyl branches are higher than those of the ethylene-based polymer obtained by the above method.

(V) Zero shear viscosity [η ₀ (P)] at 200 ° C. and weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) satisfy the following relational expression.
0.10 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 60 × 10 ⁻³¹ × Mw ^6.8
Preferably, the following relational expression is satisfied.
0.50 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 30 × 10 ⁻³¹ × Mw ^6.8
More preferably, the following relational expression is satisfied.
1.00 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 15 × 10 ⁻³¹ × Mw ^6.8

When zero-shear viscosity [η ₀ (P)] is log-log plotted against weight average molecular weight (Mw), the extensional viscosity is strain-hardening like a linear ethylene polymer without long-chain branching. No resin follows a power law with a slope of about 3.4. On the other hand, high-pressure low-density polyethylene is known to exhibit zero shear viscosity [η ₀ (P)] lower than the power law of linear ethylene-based polymers, which has a relatively short long-chain branching. It is estimated to have many. The extensional viscosity of an ethylene polymer that exhibits zero shear viscosity [η ₀ (P)] lower than the power law of a linear ethylene polymer, such as high-pressure low-density polyethylene, is stronger as the strain rate increases. It is known to exhibit strain hardening (strain rate hardening).

In contrast, an ethylene polymer having a long chain branch obtained by a metallocene catalyst is known to exhibit a zero shear viscosity [η ₀ (P)] higher than the power law of a linear ethylene polymer. This is presumed to have a small amount of long long-chain branching. Elongation of an ethylene polymer exhibiting a zero shear viscosity [η ₀ (P)] higher than the power law of a linear ethylene polymer, such as an ethylene polymer having a long chain branch obtained by a metallocene catalyst It is known that viscosity does not depend on strain rate and strain hardening is relatively weak. (H. Munstedt, D. Auhl, J. Non-Newtonian Fluid Mech., 128, 62-69 (2005), C Gabriel, H. Munstedt, J. Rheol., 47 (3), 619 (2003)).

In general, when the extensional viscosity shows strain hardening, the melt tension increases. Therefore, the zero shear viscosity [η ₀ (P)], which is lower than the power law of the linear ethylene polymer, is exhibited as in the high-pressure low-density polyethylene. An ethylene polymer has a high melt tension in a region where the strain rate is high. Since bubble growth in foam molding has a relatively high strain rate, if the zero shear viscosity [η ₀ (P)] at 200 ° C. is in the above range, the melt tension during bubble growth increases. For this reason, it becomes difficult for bubbles to break, and a good foamed state having uniform bubbles is obtained.

The relationship between the zero shear viscosity [η ₀ (P)] and the weight average molecular weight (Mw) is considered to depend on the content and length of the long chain branch in the ethylene polymer. The greater the number of long-chain branches and the shorter the length of the long-chain branches, the zero shear viscosity [η ₀ (P)] is closer to the lower limit of the claims. The smaller the long-chain branch content, the longer the long-chain branches. The zero shear viscosity [η ₀ (P)] is considered to be close to the upper limit of the claims. When the relationship between the zero shear viscosity [η ₀ (P)] and the weight average molecular weight (Mw) is within the range of the claimed range, the foam of the resulting foam is less likely to break and the foam is uniformly distributed. A state is obtained.

As described above, the long chain branching content is increased by increasing the ratio ([A] / [A + B]) of the component (A) in the ethylene polymer production catalyst. From this, it is possible to produce an ethylene-based polymer having the claimed zero shear viscosity [η ₀ (P)] by increasing or decreasing [A] / [A + B].
(VI) The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is 1.0 × 10 ^{4.20 to} 1.0 × 10 ^4.60 , preferably 1.0 × 10 ^4.30 to 1 The range is ^{.0x10 4.50} .

  It is known that low molecular weight components have a strong influence on the mechanical strength of ethylene polymers. The presence of low molecular weight components is thought to decrease the mechanical strength due to an increase in molecular ends that are considered to be the starting point of destruction (edited by Kazuo Matsuura and Naotaka Mikami, “Polyethylene Technology Reader”, Industrial Research Co., Ltd.) Association, 2001, p. 45).

  When the molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is in the above range, the mechanical strength is excellent because there are few low molecular weight components that adversely affect the mechanical strength.

  It is known that the molecular weight at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is determined by the composition ratio (hydrogen / ethylene) of hydrogen and ethylene in the polymerization reaction system (for example, Soga). Kazuo et al., “Catalytic Olefin Polymerization”, Kodansha Scientific, 1990, p. 376). For this reason, it is possible to increase or decrease the molecular weight at the maximum weight fraction in the molecular weight distribution curve by increasing or decreasing hydrogen / ethylene.

In addition to the above requirements, the ethylene polymer according to the present invention preferably further satisfies the following requirements (VII) and (VIII).
(VII) Intrinsic viscosity [η] (dl / g) measured in decalin at 135 ° C. and weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) are preferably the following relational expressions [Eq-1] is satisfied.
0.80 × 10 ⁻⁴ × Mw ^0.776 ≦ [η] ≦ 1.65 × 10 ⁻⁴ × Mw ^0.776 [Eq-1]
More preferably, the following relational expression [Eq-2] is satisfied.
0.90 × 10 ⁻⁴ × Mw ^0.776 ≦ [η] ≦ 1.55 × 10 ⁻⁴ × Mw ^0.776 [Eq-2]
Particularly preferably, the following relational expression [Eq-3] is satisfied.
0.90 × 10 ⁻⁴ × Mw ^0.776 ≦ [η] ≦ 1.40 × 10 ⁻⁴ × Mw ^0.776 [Eq-3]

  When long chain branching is introduced into an ethylene polymer, the intrinsic viscosity [η] (dl / g) may be reduced relative to the molecular weight compared to a linear ethylene polymer without long chain branching. (For example, Walter Burchard, ADVANCES IN POLYMER SCIENCE, 143, Branched Polymer II, p. 137 (1999)).

  Therefore, when the intrinsic viscosity [η] (dl / g) is in the above range, the resulting ethylene polymer has a large number of long-chain branches and a high melt tension, so that the expansion ratio can be increased. And a good foamed state in which bubbles are uniformly distributed is obtained.

(VIII) Shear viscosity [η ^* (100)] (P) at 200 ° C. and angular velocity 100 rad / sec, and Shear viscosity [η ^* (1.0)] (P) at 200 ° C. and angular velocity 1.0 rad / sec The ratio [η ^* (100) / η ^* (1.0)] is preferably in the range of 0.04 to 0.40.

It is known that when long chain branching is introduced into an ethylene polymer, the shear viscosity in a region where the shear rate is high is smaller than that of a linear ethylene polymer without long chain branching. (For example, Hosoda, “Polymer”, 2007, Vol. 56, p.342), [η ^* (100) / η ^* (1.0)] becomes smaller. When [η ^* (100) / η ^* (1.0)] is in the above range, the resulting ethylene-based polymer has excellent extrusion characteristics because of its low shear viscosity in a high shear rate region.

<Method for producing ethylene polymer>
The manufacturing method of the ethylene polymer of this invention is demonstrated.
The ethylene polymer of the present invention can be produced by polymerizing ethylene or ethylene and an α-olefin having 4 to 20 carbon atoms in the presence of a catalyst for producing an ethylene polymer to be described later.

In the present invention, a liquid phase polymerization method such as solution polymerization or suspension polymerization, or a polymerization method such as a gas phase polymerization method is used, and a suspension polymerization method or a gas phase polymerization method is preferably used.
Specific examples of the inert hydrocarbon medium used in the liquid phase polymerization method include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, and methyl. And alicyclic hydrocarbons such as cyclopentane; aromatic hydrocarbons such as benzene, toluene and xylene; and halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane or mixtures thereof. Moreover, alpha-olefin itself can also be used as a solvent.

Catalyst for producing ethylene polymer The ethylene polymer of the present invention is ethylene or ethylene and α having 4 to 20 carbon atoms in the presence of a catalyst containing component (A), component (B) and component (C). -It can be produced efficiently by polymerizing with olefins.

  The catalyst for producing an ethylene polymer used in the present invention may further contain a solid carrier (S) in addition to the components (A), (B) and (C) described below. The catalyst includes a solid support (S), the above-described component (C) and the solid-state catalyst component (K1) formed from the above-mentioned component (A), the solid-state support (S), the above-mentioned component (C) and the above-mentioned component. The solid catalyst formed from the catalyst for olefin polymerization comprising the solid catalyst component (K2) formed from (B), the solid carrier (S), the component (A), the component (B) and the component (C). An olefin polymerization catalyst comprising the catalyst component (K3) may be mentioned.

Each component used in the olefin polymerization catalyst will be described.
Component (A) : A bridged metallocene compound represented by the following general formula (I).

一般式（Ｉ）中、Ｍは周期表第４族遷移金属原子を示し、具体的には、チタン、ジルコニウムおよびハフニウムから選ばれる遷移金属原子であり、好ましくはジルコニウムである。

In general formula (I), M represents a group 4 transition metal atom in the periodic table, specifically a transition metal atom selected from titanium, zirconium and hafnium, preferably zirconium.

R ^{1 to} R ⁴ are hydrogen atoms, hydrocarbon groups having 1 to 20 carbon atoms, halogen-containing groups, oxygen-containing groups, nitrogen-containing groups, boron-containing groups, sulfur-containing groups, phosphorus-containing groups, silicon-containing groups, germanium-containing Selected from a group and a tin-containing group, which may be the same or different from each other, but not all are hydrogen atoms at the same time. R ^{1 to} R ⁴ may be bonded to each other to form an aliphatic ring.

  Examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, and an arylalkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, Examples include n-octyl group, nonyl group, dodecyl group, and eicosyl group. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group. Examples of the alkenyl group include a vinyl group, a propenyl group, and a cyclohexenyl group. The aryl group includes phenyl, tolyl, dimethylphenyl, trimethylphenyl, ethylphenyl, propylphenyl, biphenyl, α- or β-naphthyl, methylnaphthyl, anthracenyl, phenanthryl, benzylphenyl, pyrenyl, acenaphthyl, phenalenyl, aceanthrylenyl, Tetrahydronaphthyl, indanyl and biphenylyl. Arylalkyl groups include benzyl, phenylethyl and phenylpropyl.

Examples of the halogen-containing group include a halogen-containing hydrocarbon group in which a hydrogen atom of the hydrocarbon group is substituted with a halogen.
Examples of the oxygen-containing group include an alkoxy group, an aryloxy group, an acyl group, and an ester group.

Examples of nitrogen-containing groups include amino groups, imino groups, amide groups, imide groups, nitro groups, and cyano groups. Examples of boron-containing groups include alkyl-substituted boron, aryl-substituted boron, boron halide, and alkyl-substituted boron halides. Etc.

Examples of the sulfur-containing group include an alkylthio group, an arylthio group, a thioester group, a sulfone ester group, and a sulfonamide group.
Examples of the phosphorus-containing group include a trialkylphosphine group, a triarylphosphine group, a phosphite group (phosphide group), a phosphonic acid group, and a phosphinic acid group.

Examples of the silicon-containing group include a silyl group, a hydrocarbon-substituted silyl group, and a hydrocarbon-substituted siloxy group.
Examples of the germanium-containing group and the tin-containing group include those in which silicon of the silicon-containing group is replaced with germanium or tin.

A more preferable group of R ^{1 to} R ⁴ is a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, more preferably three of the substituents of R ^{1 to} R ⁴ are hydrogen atoms, and the remaining one is an alkyl group having 1 to 15 carbon atoms, particularly preferably three of the substituents R ¹ to R ⁴ are hydrogen atoms, but the remaining one is an alkyl group having from 2 to 15 carbon atoms.

Q ¹ is a divalent group that binds two ligands, and includes a hydrocarbon group having 1 to 20 carbon atoms such as an alkylene group, a substituted alkylene group, and an alkylidene group, a halogen-containing group, a silicon-containing group, and a germanium-containing group. A group selected from a group and a tin-containing group, particularly preferably a silicon-containing group.

  Specific examples of the alkylene group, substituted alkylene group and alkylidene group include alkylene groups such as methylene, ethylene, propylene and butylene; isopropylidene, diethylmethylene, dipropylmethylene, diisopropylmethylene, dibutylmethylene, methylethylmethylene, methylbutylmethylene Methyl-t-butylmethylene, dihexylmethylene, dicyclohexylmethylene, methylcyclohexylmethylene, methylphenylmethylene, diphenylmethylene, ditolylmethylene, methylnaphthylmethylene, dinaphthylmethylene, 1-methylethylene, 1,2-dimethylethylene and 1 A substituted alkylene group such as ethyl-2-methylethylene; cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, Kurohepuchiriden, bicyclo [3.3.1] nonylidene, norbornylidene, adamantylidene, cycloalkylidene group and ethylidene such tetrahydronaphthyl dust den and dihydroindolyl mites alkylidene, and the like alkylidene group such as propylidene and butylidene.

  Examples of silicon-containing groups include silylene, methylsilylene, dimethylsilylene, diisopropylsilylene, dibutylsilylene, methylbutylsilylene, methyl-t-butylsilylene, dicyclohexylsilylene, methylcyclohexylsilylene, methylphenylsilylene, diphenylsilylene, ditolylsilylene, methyl Examples include naphthylsilylene, dinaphthylsilylene, cyclodimethylenesilylene, cyclotrimethylenesilylene, cyclotetramethylenesilylene, cyclopentamethylenesilylene, cyclohexamethylenesilylene, cycloheptamethylenesilylene, and the like, particularly preferably dimethylsilylene group and dibutyl And dialkylsilylene groups such as a silylene group.

X is each independently an atom or group selected from a hydrogen atom, a halogen atom, a hydrocarbon group, a halogen-containing hydrocarbon group, a silicon-containing group, an oxygen-containing group, a sulfur-containing group, a nitrogen-containing group, and a phosphorus-containing group. Preferably a halogen atom or a hydrocarbon group. Examples of the halogen atom include fluorine, chlorine, bromine and iodine, and particularly preferably chlorine. Examples of the hydrocarbon group, the same groups as those hydrocarbon groups of R ¹ to R ⁴ described above, preferably an alkyl group having 1 to 20 carbon atoms. As the halogen-containing hydrocarbon group, silicon-containing group, oxygen-containing group, sulfur-containing group, nitrogen-containing group and phosphorus-containing group, the above-mentioned halogen-containing hydrocarbon groups of R ^{1 to} R ⁴ , silicon-containing group, oxygen-containing group, The thing similar to a sulfur containing group, a nitrogen containing group, and a phosphorus containing group is mentioned.

  Preferred specific examples of component (A) include dimethylsilylene (cyclopentadienyl) (3-ethylcyclopentadienyl) zirconium dichloride, dimethylsilylene (cyclopentadienyl) (3-n-propylcyclopentadienyl) zirconium. Dichloride, dimethylsilylene (cyclopentadienyl) (3-n-butylcyclopentadienyl) zirconium dichloride, dimethylsilylene (cyclopentadienyl) (3-n-octylcyclopentadienyl) zirconium dichloride, dibutylsilylene (cyclo Pentadienyl) (3-n-propylcyclopentadienyl) zirconium dichloride, dimethylsilylene (cyclopentadienyl) (3-n-butylcyclopentadienyl) zirconium dichloride, dimethylsilylene ( Clopentadienyl) (3-n-octylcyclopentadienyl) zirconium dichloride, trifluoromethylbutylsilylene (cyclopentadienyl) (3-n-propylcyclopentadienyl) zirconium dichloride, trifluoromethylbutylsilylene ( Cyclopentadienyl) (3-n-butylcyclopentadienyl) zirconium dichloride and trifluoromethylbutylsilylene (cyclopentadienyl) (3-n-octylcyclopentadienyl) zirconium dichloride, and the like. Specific examples include dimethylsilylene (cyclopentadienyl) (3-n-propylcyclopentadienyl) zirconium dichloride and dimethylsilylene (3-n-butylcyclopentadienyl) (cyclopentadienyl). Yl) including zirconium dichloride.

Component (B) : A bridged metallocene compound represented by the following general formula (II).

一般式（ＩＩ）中、Ｍは周期表第４族遷移金属原子を示し、具体的には、チタン、ジルコニウムおよびハフニウムから選ばれる遷移金属原子であり、好ましくはジルコニウムである。

In the general formula (II), M represents a Group 4 transition metal atom in the periodic table, specifically a transition metal atom selected from titanium, zirconium and hafnium, preferably zirconium.

R ^{5 to} R ¹⁶ are hydrogen atoms, hydrocarbon groups, halogen-containing groups, oxygen-containing groups, nitrogen-containing groups, boron-containing groups, sulfur-containing groups, phosphorus-containing groups, silicon-containing groups, germanium-containing groups, and tin-containing groups. And may be the same or different from each other, and two adjacent groups may be connected to each other to form a ring. R ^{5 to} R ¹⁶ are preferably a hydrogen atom or a hydrocarbon group. Among these, among R ^{5 to} R ¹⁶ , R ^{5 to} R ⁸ are hydrogen atoms, and R ^{9 to} R ¹⁶ are more preferably hydrogen atoms or hydrocarbon groups having 1 to 20 carbon atoms. It is preferable that at least one set of hydrogen groups is bonded to each other to form a ring, for example, an octahydrodibenzofluorenyl group or an octamethyloctahydrodibenzofluorenyl group.

Among hydrocarbon groups, halogen-containing groups, oxygen-containing groups, nitrogen-containing groups, boron-containing groups, sulfur-containing groups, phosphorus-containing groups, silicon-containing groups, germanium-containing groups, and tin-containing groups, as hydrocarbon groups, those similar to the hydrocarbon groups R ¹ to R ⁴ described above can be mentioned. As the halogen-containing hydrocarbon group, silicon-containing group, oxygen-containing group, sulfur-containing group, nitrogen-containing group and phosphorus-containing group, the above-mentioned halogen-containing hydrocarbon groups of R ^{1 to} R ⁴ , silicon-containing group, oxygen-containing group, The thing similar to a sulfur containing group, a nitrogen containing group, and a phosphorus containing group is mentioned.

Q ² is a divalent group that binds two ligands, and includes a hydrocarbon group having 1 to 20 carbon atoms such as an alkylene group, a substituted alkylene group, and an alkylidene group, a halogen-containing group, a silicon-containing group, and germanium. And a group selected from a tin-containing group, preferably a hydrocarbon group having 1 to 20 carbon atoms such as an alkylene group, a substituted alkylene group and an alkylidene group, and a silicon-containing group, particularly preferably an alkylene group or a substituted group. It is a C1-C10 hydrocarbon group such as an alkylene group or an alkylidene group. When these groups are used as Q ² , the improvement of the molecular weight of the ethylene polymer is relatively suppressed, and the amount of macromonomer produced from component (A) is reduced by reducing the amount of hydrogen supplied in the polymerization reaction system. Is expected to increase the number of long-chain branches.

Specific examples of the hydrocarbon group having 1 to 20 carbon atoms such as an alkylene group, a substituted alkylene group, and an alkylidene group, and a halogen-containing group, a silicon-containing group, a germanium-containing group, and a tin-containing group are the same as those of Q ¹ described above. Things.

X may be the same as X in the above formula (I).
Preferred specific examples of component (B) include isopropylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride, Isopropylidene (cyclopentadienyl) (3,6-di-t-butylfluorenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (octamethyloctahydridodibenzfluorenyl) zirconium dichloride, dibutylmethylene ( Cyclopentadienyl) (fluorenyl) zirconium dichloride, dibutylmethylene (cyclopentadienyl) (2,7-di-t-butylfluorenyl) zirconium dichloride, dibutylmethylene (cyclopentadienyl) (3 -Di-t-butylfluorenyl) zirconium dichloride, dibutylmethylene (cyclopentadienyl) (octamethyloctahydridodibenzfluorenyl) zirconium dichloride, cyclohexylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, Cyclohexylidene (cyclopentadienyl) (2,7-di-t-butylfluorenyl) zirconium dichloride, Cyclohexylidene (cyclopentadienyl) (3,6-di-t-butylfluorenyl) zirconium Dichloride, cyclohexylidene (cyclopentadienyl) (octamethyloctahydridodibenzfluorenyl) zirconium dichloride, dimethylsilyl (cyclopentadienyl) (fluorenyl) zirconium dichloride, dimethylsilyl (Cyclopentadienyl) (2,7-di-t-butylfluorenyl) zirconium dichloride, dimethylsilyl (cyclopentadienyl) (3,6-di-t-butylfluorenyl) zirconium dichloride and dimethylsilyl (Cyclopentadienyl) (octamethyloctahydridodibenzfluorenyl) zirconium dichloride is mentioned, and more preferred specific example is isopropylidene (cyclopentadienyl) (2,7-di-t-butyl-9- Fluorenyl) zirconium dichloride and the like.

Component (C) : at least one compound selected from the group consisting of the following (c-1) to (c-3).
(C-1) an organometallic compound represented by the following general formula (III), (IV) or (V),
R ^a _m Al (OR ^b ) _n H _p X _q (III)
[In General Formula (III), R ^a and R ^b represent a hydrocarbon group having 1 to 15 carbon atoms, which may be the same or different from each other, X represents a halogen atom, and m represents 0 <m ≦ 3, n is 0 ≦ n <3, p is 0 ≦ p <3, q is a number 0 ≦ q <3, and m + n + p + q = 3. ]
M ^a AlR ^a ₄ (IV)
[In General Formula (IV), M ^a represents Li, Na or K, and R ^a represents a hydrocarbon group having 1 to 15 carbon atoms. ]
R ^a _r M ^b R ^b _s X _t (V)
[In General Formula (V), R ^a and R ^b represent a hydrocarbon group having 1 to 15 carbon atoms, which may be the same or different from each other, M ^b represents Mg, Zn or Cd, and X represents Represents a halogen atom, r is 0 <r ≦ 2, s is 0 ≦ s ≦ 1, t is 0 ≦ t ≦ 1, and r + s + t = 2. ]

(C-2) an organoaluminum oxy compound, and
(C-3) a compound that reacts with component (A) and component (B) to form an ion pair,
At least one compound selected from the group consisting of

As the compound (c-1), compounds disclosed in JP-A-11-315109 and EP0874005A by the present applicant can be used without limitation.
Among the organometallic compounds (c-1) represented by the general formula (III), (IV) or (V), those represented by the general formula (III) are preferable, specifically, trimethylaluminum, triethyl Trialkylaluminums such as aluminum, triisopropylaluminum, triisobutylaluminum, trihexylaluminum and trioctylaluminum; and dimethylaluminum hydride, diethylaluminum hydride, diisopropylaluminum hydride, di-n-butylaluminum hydride, diisobutylaluminum hydride and diiso Examples include alkyl aluminum hydrides such as hexyl aluminum hydride.

These are used singly or in combination of two or more.
As the compound (c-2), an organoaluminum oxy compound prepared from trialkylaluminum or tricycloalkylaluminum is preferable, and an aluminoxane prepared from trimethylaluminum or triisobutylaluminum is particularly preferable. Such organoaluminum oxy compounds are used singly or in combination of two or more.

  Examples of the compound (c-3) include JP-A-1-501950, JP-A-1-502036, JP-A-3-179005, JP-A-3-179006, JP-A-3-207703, Lewis acids, ionic compounds, borane compounds and carborane compounds as well as heteropoly compounds and isopoly compounds described in Kaihei 3-207704 and US Pat. No. 5,321,106 can be used without limitation.

  In the catalyst for producing an ethylene-based polymer used in the present invention, when an organoaluminum oxy compound such as methylaluminoxane is used as a co-catalyst component, it not only exhibits very high polymerization activity for α-olefin, but also a solid carrier. The solid support component containing the promoter component can be easily prepared by reacting with the active hydrogen therein. For this reason, it is preferable to use the organoaluminum oxy compound (c-2) as the component (C).

Next, the solid carrier (S) (hereinafter also simply referred to as “component (S)”) will be described in detail.
The solid carrier (S) used in the present invention is an inorganic or organic compound, and is a granular or fine particle solid on which the above components (A) to (C) are supported.

Among these, examples of the inorganic compound include porous oxides, inorganic chlorides, clays, clay minerals, and ion-exchangeable layered compounds, and porous oxides are preferable.
Examples of the porous oxide include SiO ₂ , Al ₂ O ₃ , MgO, ZrO, TiO ₂ , B ₂ O ₃ , CaO, ZnO, BaO and ThO ₂ , or a composite or mixture containing these, specifically Natural or synthetic zeolite, SiO ₂ —MgO, SiO ₂ —Al ₂ O ₃ , SiO ₂ —TiO ₂ , SiO ₂ —V ₂ O ₅ , SiO ₂ —Cr ₂ O _3, SiO ₂ —TiO ₂ —MgO, etc. Used. Of these, those containing SiO ₂ as the main component are preferred.

Such porous oxides have different properties depending on the type and production method, but the solid carrier (S) used in the present invention usually has a particle size of 0.2 to 300 μm, preferably 1 to 200 μm. Te, the specific surface area is usually 50~1200m ² / g, preferably in the range of 100~1000m ² / g, which pore volume is in the range of usually 0.3~30cm ³ / g are preferred. Such a solid carrier (S) is used, for example, after calcining at 100 to 1000 ° C., preferably 150 to 700 ° C., if necessary.

It describes about the preparation method of the catalyst for ethylene polymer manufacture used by this invention.
The above-mentioned catalyst for producing an ethylene polymer is prepared by adding the component (A), the component (B) and the component (C) into an inert hydrocarbon or a polymerization system using an inert hydrocarbon. Can do.

The order of adding each component is arbitrary, but as a preferred order, for example,
i) Method of adding component (C), component (A) and component (B) to the polymerization system in this order ii) Component (C), component (B) and component (A) being added to the polymerization system in this order Method iii) Method in which component (A) and component (C) mixed and contacted are added to the polymerization system, and then component (B) is added to the polymerization system iv) Component (B) and component ( A method in which the contact product obtained by mixing and contacting C) is added to the polymerization system, and then component (A) is added to the polymerization system. V) Component (C) is added to the polymerization system, and then components (A) and Method of adding the contact product obtained by mixing and contacting the component (B) into the polymerization system vi) Adding the component (C), the component (A) and the component (B) in this order into the polymerization system, and again the component (C) Vii) Addition of component (C), component (B) and component (A) to the polymerization system in this order, Method of adding (C) into the polymerization system viii) Adding the contact product obtained by mixing and contacting the component (A) and the component (C) into the polymerization system, and then adding the component (B) into the polymerization system. Method of adding component (C) again into the polymerization system ix) Add the contact product obtained by mixing and contacting component (B) and component (C) into the polymerization system, and then add component (A) into the polymerization system And x) adding the component (C) to the polymerization system again x) adding the component (C) to the polymerization system and then mixing and contacting the component (A) and the component (B) in the polymerization system And a method of adding the component (C) to the polymerization system again.

  The catalyst for producing an ethylene polymer comprises a solid catalyst component (K1) formed from a solid carrier (S), a component (C) and a component (A), a solid carrier (S), and a component (C). And the solid catalyst component (K2) formed from the component (B) can be prepared by adding them into an inert hydrocarbon or into a polymerization system using an inert hydrocarbon.

Although the contact order of each component is arbitrary, as a preferable method, for example,
xi) contacting the component (C) and the component (S), then contacting the component (A), contacting the solid catalyst component (K1), the component (C) and the component (S), Method using solid catalyst component (K2) prepared by contacting component (B) xii) Solid catalyst prepared by mixing and contacting component (A) and component (C) and then contacting component (S) Method using component (K1), solid catalyst component (K2) prepared by bringing component (B) and component (C) into contact with mixing and then contacting with component (S) xiii) Component (C) and component The solid catalyst component (K1) prepared by contacting (S) and then contacting the contact product of component (A) and component (C), component (C) and component (S), Next, the solid catalyst component (K2) prepared by bringing the contact product of component (B) and component (C) into contact with each other A solid catalyst component (K1) prepared by bringing component (C) and component (S) into contact, then contacting component (A), and then contacting component (C) again; Examples include a method using a solid catalyst component (K2) prepared by bringing (C) and component (S) into contact, then bringing component (B) into contact, and then contacting component (C) again. Among these, particularly preferable contact order includes xi) and xiii).

  The solid catalyst component (K3) according to the present invention is prepared by contacting the component (A), the component (B), the component (C) and the solid carrier (S) in an inert hydrocarbon. Can do.

The order of contacting the components is arbitrary, but as a preferred order, for example,
xv) Method of preparing component (S) by mixing component (C), then contacting component (A), and then contacting component (B) xvi) Component (S) with component (C) Method of mixing and contacting component (B), and then contacting component (A) to prepare xvii) Component (S) is mixed and contacted with component (S), and then component (A) and component ( A method of contacting the contact mixture with B),
xviii) a method in which component (A) and component (B) are mixed and contacted, then contacted with component (C), and subsequently contacted with component (S);
xix) A method in which the component (C) is contacted with the component (S), further contacted with the component (C), and then contacted in the order of the component (A) and the component (B),
xx) a method of contacting the component (S) with the component (C), further contacting the component (C), and then contacting the component (B) and then the component (A) in this order;
xxi) a method in which the component (S) is contacted with the component (S), the component (C) is further contacted, and then the contact mixture of the component (A) and the component (B) is contacted;
xxii) A method in which component (C) is mixed and contacted with component (S), and then a contact mixture of component (A), component (B) and component (C) is contacted,
xxiii) A method in which component (C) is mixed and contacted with component (S), then a contact mixture of component (A) and component (C) is contacted, and further component (B) is contacted,
xxiv) A method in which component (C) is mixed and contacted with component (S), then a contact mixture of component (B) and component (C) is contacted, and further component (A) is contacted,
xxv) The component (C) is contacted with the component (S), and the component (C) is further contacted, and then the contact mixture of the component (A) and the component (C), the component (B) and the component (C) Contacting the mixture in the order of contact with the
xxvi) After contacting the component (S) with the component (C) and further contacting the component (C), then a contact mixture of the component (B) and the component (C), component (A) and the component (C) Contacting the mixture in the order of contact with the
xxvii) A method of contacting the component (S) with the component (C), further contacting the component (C), and then contacting the contact mixture of the component (A), the component (B) and the component (C),
xxviii) A mixture of component (A) and component (C) and a mixture of component (B) and component (C) are mixed in advance, and this is brought into contact with the contact product of component (S) and component (C). How to
xxix) A mixture of the component (A) and the component (C) and a mixture of the component (B) and the component (C) are mixed in advance, and this is mixed with the component (S), the component (C), and further the component (C). A method of bringing a contact object into contact with
Etc. When a plurality of components (C) are used, the components (C) may be the same or different. Among these, particularly preferable contact order includes xvi), xx), xxi), xxvi), xxvii), and xxviii).

  In each method showing the contact order form, the step (P1) including contact between the component (S) and the component (C), the step (P2) including contact between the component (S) and the component (A), and the component In step (P3) including contact between (S) and component (B), and in step (P4) including contact between component (S), component (A) and component (B), component (G) (g -1) polyalkylene oxide block, (g-2) higher aliphatic amide, (g-3) polyalkylene oxide, (g-4) polyalkylene oxide alkyl ether, (g-5) alkyldiethanolamine, and (g- 6) At least one compound selected from polyoxyalkylene alkylamines may coexist. By allowing the component (G) to coexist, fouling during the polymerization reaction is suppressed, and the particle properties of the produced polymer are improved. Among the components (G), (g-1), (g-2), (g-3) and (g-4) are preferable, and (g-1) and (g-2) are particularly preferable.

  Solvents used for the preparation of the solid catalyst component include inert hydrocarbon solvents, specifically, aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane and kerosene; And alicyclic hydrocarbons such as pentane, cyclohexane and methylcyclopentane; aromatic hydrocarbons such as benzene, toluene and xylene; and halogenated hydrocarbons such as ethylene chloride, chlorobenzene and dichloromethane or mixtures thereof.

  The contact between the component (C) and the component (S) is chemically combined by the reaction between the reaction site in the component (C) and the reaction site in the component (S), and the component (C) and the component (S). The contact material is formed. The contact time between component (C) and component (S) is usually 0 to 20 hours, preferably 0 to 10 hours, and the contact temperature is usually -50 to 200 ° C, preferably -20 to 120 ° C. . When the initial contact between the component (C) and the component (S) is suddenly performed, the component (S) collapses due to the reaction heat generation or reaction energy, and the morphology of the resulting solid catalyst component deteriorates, and this is used for polymerization. The continuous operation is often difficult due to poor polymer morphology. Therefore, the initial contact between the component (C) and the component (S) can be maintained at a low temperature of -20 to 30 ° C. for the purpose of suppressing the reaction exotherm, or the reaction exotherm can be controlled to maintain the initial contact temperature. It is preferred to react at a rate. The same applies to the case where the component (C) and the component (S) are brought into contact with each other and the component (C) is further brought into contact. The molar ratio of contact between the component (C) and the component (S) (component (C) / component (S)) can be arbitrarily selected, but the higher the molar ratio, the higher the component (A) and the component (B). And the activity per solid catalyst component can be improved.

  The molar ratio of component (C) and component (S) [= molar amount of component (C) / molar amount of component (S)] is usually 0.2 to 2.0, particularly preferably 0.4 to 2. 0. The contact time between the contact product of component (C) and component (S) and component (A) and component (B) is usually 0 to 5 hours, preferably 0 to 2 hours, and the contact temperature is usually − 50 to 200 ° C, preferably -50 to 100 ° C. The amount of contact between component (A) and component (B) largely depends on the type and amount of component (C). When component (c-1) is used, component (A) and component (B) The molar ratio [(c-1) / M] of all transition metal atoms (M) and component (c-1) is usually 0.01 to 100,000, preferably 0.05 to 50,000. When component (c-2) is used, the molar ratio of aluminum atoms in component (c-2) to all transition metal atoms (M) in components (A) and (B) [( c-2) / M] is usually used in an amount of 10 to 500,000, preferably 20 to 100,000. When component (c-3) is used, component (c-3) and component (A) And the molar ratio [(c-3) / M] to all transition metal atoms (M) in the component (B) is usually 1 to 10, preferably 1 to Used in an amount to be. The ratio of component (C) to all transition metal atoms (M) in component (A) and component (B) is determined by inductively coupled plasma (ICP) emission spectroscopy.

  The use ratio of the component (A) and the component (B) can be arbitrarily determined from the molecular weight and molecular weight distribution of the ethylene polymer, but as a preferred range, the ratio of the polymer produced from the component (A) and the component (B) [ = Amount of polymer produced by component (A) / Amount of polymer produced by component (B)] is usually 40/60 to 95/5, preferably 50/50 to 95/5, more preferably 60/40 to 95/5. It is. A larger amount of the polymer derived from component (A) is advantageous for producing long chain branching. The molar ratio of the component (A) and the component (B) per transition metal compound may be used so that the resulting polymer satisfies the above ratio, and the contact product of the component (S) and the component (C) and the component It can be arbitrarily selected based on the activity ratio expressed from the solid catalyst component in which (A) or component (B) is contacted independently.

  For the (co) polymerization of olefins, the solid catalyst component as described above can be used as it is, but it is also possible to preliminarily polymerize the olefin in this solid catalyst component to form a prepolymerized solid catalyst component.

  The prepolymerized solid catalyst component can be prepared by prepolymerizing an olefin in the presence of the solid catalyst component, usually in an inert hydrocarbon solvent, and can be prepared by any of batch, semi-continuous and continuous methods. However, it can be used under reduced pressure, normal pressure or increased pressure. By this prepolymerization, 0.01 to 1000 g, preferably 0.1 to 800 g, more preferably 0.2 to 500 g of a prepolymerized solid catalyst component per 1 g of the solid catalyst component is produced.

  After separating the prepolymerized solid catalyst component produced in the inert hydrocarbon solvent from the suspension, it may be suspended again in the inert hydrocarbon, and the olefin may be introduced into the resulting suspension. Further, olefin may be introduced after drying.

In the prepolymerization, the prepolymerization temperature is usually −20 to 80 ° C., preferably 0 to 60 ° C., and the prepolymerization time is usually 0.5 to 100 hours, preferably 1 to 50 hours.
As the form of the solid catalyst component used for the prepolymerization, those already described can be used without limitation. Moreover, a component (C) is used as needed, and especially the organoaluminum compound shown by the said Formula (III) in (c-1) is used preferably. When the component (C) is used, the molar ratio of the aluminum atom (Al-C) and the transition metal compound in the component (C) (component (C) / transition metal compound) is usually 0.1 to 10,000. It is preferably used in an amount of 0.5 to 5000.

  The concentration of the solid catalyst component in the prepolymerization system is usually 1 to 1000 g / liter, preferably 10 to 500 g / liter, in a ratio of solid catalyst component / polymerization volume of 1 liter. At the time of prepolymerization, the component (G) can coexist for the purpose of suppressing fouling or improving particle properties. Component (G) may be brought into contact with a prepolymer once produced by prepolymerization.

When polymerization of ethylene or ethylene and an α-olefin having 4 to 20 carbon atoms is carried out using an ethylene polymer production catalyst, the component (A) and the component (B) Usually, it is used in an amount of 10 ⁻¹² to 10 ⁻¹ mol, preferably 10 ⁻⁸ to 10 ⁻² mol. In addition, component (C) is used, and an organoaluminum compound represented by formula (III) is particularly preferably used in (c-1).

Moreover, the polymerization temperature of the olefin using the above-mentioned solid catalyst component is usually in the range of −50 to 200 ° C., preferably 0 to 170 ° C., particularly preferably 60 to 170 ° C. The polymerization pressure is usually normal pressure ~100kg heavy / cm ^2, preferably under normal pressure ~50kg heavy / cm ^2, the polymerization reaction is batchwise, in any of the methods of the semi-continuous and continuous It can be carried out. Furthermore, the polymerization can be carried out in two or more stages having different reaction conditions.

  The molecular weight of the resulting ethylene polymer can be adjusted by allowing hydrogen to be present in the polymerization system or changing the polymerization temperature. At the time of polymerization, the component (G) can coexist for the purpose of suppressing fouling or improving particle properties.

  In order to suppress variation in physical property values, the ethylene polymer particles obtained by the polymerization reaction and other components added as desired are melted by an arbitrary method, kneaded, granulated, and the like.

<Resin composition for foam molding>
By blending the ethylene-based polymer for foam molding of the present invention with a thermoplastic resin, a resin composition for foam molding excellent in moldability and mechanical strength can be obtained.

  The thermoplastic resin is not particularly limited as long as it is a thermoplastic resin other than an ethylene polymer for foam molding. Specifically, an ethylene polymer, a propylene polymer, a butene polymer, 4-methyl Examples thereof include polyolefins such as a -1-pentene polymer, a 3-methyl-1-butene polymer, and a hexene polymer, which do not satisfy the above-described requirements (I) to (VI). Of these polyolefins, ethylene-based polymers are preferred. A thermoplastic resin may be used individually by 1 type, and may be used in combination of 2 or more type.

The thermoplastic resin is produced by liquid phase polymerization, gas phase polymerization, or high-pressure radical polymerization using an ordinary Ziegler-Natta catalyst or metallocene catalyst.
The blend ratio of the ethylene-based polymer for foam molding of the present invention and the thermoplastic resin is usually 90/10 to 10/90, preferably 70/30 to 10/90, more preferably 50/50 to 20/80. It is.

By blending the ethylene polymer according to the present invention with the thermoplastic resin, a foam molding resin composition having excellent moldability and mechanical strength can be obtained.
The foam molding resin composition of the present invention includes a weather resistance stabilizer, a heat resistance stabilizer, an antistatic agent, an anti-slip agent, an anti-blocking agent, an antifogging agent, a lubricant, a pigment, as long as the object of the present invention is not impaired. You may mix | blend additives, such as dye, a nucleating agent, a plasticizer, anti-aging agent, hydrochloric acid absorber, and antioxidant.

<Method for producing foam>
As a method for producing the foam of the present invention, any method may be used as long as the foam is obtained. Examples thereof include the following production methods.

(1) Extrusion Foaming Method When an ethylene-based polymer for foam molding or a resin composition containing the polymer is placed in a hopper of an extruder and extruded at a temperature near these melting points, press-fitting provided in the middle of the extruder A foam can be continuously obtained by press-fitting a physical foaming agent from the hole and extruding from a die having a desired shape. As the physical foaming agent, for example, volatile foaming agents such as Freon, butane, pentane, hexane and cyclohexane, and inorganic gas-based foaming agents such as nitrogen, air, water and carbon dioxide are used. In addition, a bubble nucleating agent such as calcium carbonate, talc, clay and magnesium oxide may be added during extrusion foaming.

  The blending ratio of the physical foaming agent is usually 0.5 to 60 parts by weight, preferably 0.5 to 40 parts by weight, with respect to 100 parts by weight of the ethylene-based polymer for foam molding or the resin composition containing the polymer. More preferably, it is 0.5 to 20 parts by weight. When the blending ratio of the physical foaming agent is less than the above range, the foaming ratio of the foam tends to decrease, and when it exceeds the above range, the strength of the foam tends to decrease.

(2) Foaming method using thermally decomposable foaming agent A single-screw extruder containing an ethylene polymer for foam molding or a resin composition containing the polymer, a thermally decomposable foaming agent, and other additives as required After melt-kneading at a temperature lower than the decomposition temperature of the thermally decomposable foaming agent using a kneading apparatus such as a twin-screw extruder, Banbury mixer, kneader mixer and roll, it is generally formed into a sheet.

  Next, when the sheet is heated to a temperature higher than the decomposition temperature of the foaming agent and foamed, a foam can be obtained. The pyrolytic foaming agent is not particularly limited as long as it decomposes when the resin is heated and melted to generate gas, and a general organic or inorganic chemical foaming agent can be used.

  Specifically, azo compounds such as azodicarbonamide, 2,2′-azobisisobutyronitrile, azohexahydrobenzonitrile and diazoaminobenzene, benzenesulfonyl hydrazide, benzene-1,3-sulfonyl hydrazide, diphenylsulfone Sulfonyl hydrazide compounds such as 3,3′-disulfonyl hydrazide, diphenyl oxide-4,4′-disulfonyl hydrazide, 4,4′-oxybis (benzenesulfonyl hydrazide) and p-toluenesulfonyl hydrazide, N, N′— Nitroso compounds such as dinitrosopentamethylenetetramine and N, N′-dinitroso-N, N′-dimethylphthalamide, azide compounds such as terephthalazide and pt-butylbenzazide, sodium bicarbonate, bicarbonate Carbonate compounds such as Moniumu and ammonium carbonate, and these at least one is used. Of these, azodicarbonamide and 4,4'-oxybis (benzenesulfonylhydrazide) are preferable, and 4,4'-oxybis (benzenesulfonylhydrazide) is particularly preferable.

  The blending ratio of the pyrolyzable foaming agent is usually 1 to 50 parts by weight, preferably 4 to 25 parts by weight, per 100 parts by weight of the ethylene-based polymer for foam molding or the resin composition containing the polymer. When the blending ratio of the pyrolytic foaming agent is less than the above range, the foaming ratio of the foam tends to decrease, and when it exceeds the above range, the strength of the foam tends to decrease.

(3) Foaming method in a pressure vessel An ethylene-based polymer or resin composition for foam molding is molded into a sheet or block shape by a press or an extruder. Next, the molded body is put into a pressure vessel, and the physical foaming agent is sufficiently dissolved in the molded body, and then the pressure is reduced to produce the foamed body. It is also possible to fill the pressure vessel filled with the molded body with a physical foaming agent at room temperature, pressurize it, take it out after depressurization, and heat it in an oil bath or oven to foam it.

  In the present invention, if an ethylene-based polymer for foam molding or a resin composition containing the polymer is crosslinked in advance, a crosslinked foam can be obtained. Common crosslinking methods include crosslinking by thermal decomposition of peroxide radical generators in resins, crosslinking by irradiation with ionizing radiation, crosslinking by irradiation with ionizing radiation in the presence of a polyfunctional monomer, and silane crosslinking. Is mentioned. In order to obtain a crosslinked foam by such a method, an ethylene-based polymer for foam molding or a foam molding resin composition containing the polymer, a thermal decomposable foaming agent, a polyfunctional monomer and other compounds as a crosslinking aid The agent is melt-kneaded at a temperature lower than the decomposition temperature of the thermally decomposable foaming agent to form a sheet. The obtained resin composition sheet for foam molding is irradiated with a predetermined amount of ionizing radiation to crosslink the ethylene polymer, and then the crosslinked sheet is heated to a temperature equal to or higher than the decomposition temperature of the foaming agent to be foamed. Examples of ionizing radiation include α rays, β rays, γ rays, and electron beams. In addition, peroxide crosslinking or silane crosslinking can be performed instead of irradiation crosslinking with ionizing radiation.

  The foam of the present invention is suitably used for flooring materials, building materials, packaging and packaging materials, automobile interior materials, daily goods, mats, sheets, sports equipment, and the like.

EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.
[Measurement of ethylene polymer for foam molding]
A method for measuring the physical properties of the ethylene-based polymer for foam molding is shown below.

<Melt flow rate (MFR)>
According to ASTM D1238-89, it was measured under the conditions of 190 ° C. and 2.16 kg load.

<Density (d)>
The measurement sample was heat-treated at 120 ° C. for 1 hour, linearly cooled to room temperature over 1 hour, and then measured by a density gradient tube method.

<Melting tension (MT)>
The melt tension (MT) at 190 ° C. (unit: g) was determined by measuring the stress when stretched at a constant speed. For the measurement, an MT measuring machine manufactured by Toyo Seiki Seisakusho was used. The conditions are a resin temperature of 190 ° C., a melting time of 6 minutes, a barrel diameter of 9.55 mmφ, an extrusion speed of 15 mm / min, a winding speed of 24 m / min (if the molten filament breaks, the winding speed is decreased by 5 m / min. The nozzle diameter was 2.095 mmφ and the nozzle length was 8 mm.

<Shear viscosity (η ^* )>
The shear viscosity [η ^* (1.0)] (P) at 200 ° C. and an angular velocity of 1.0 rad / sec and the shear viscosity [η ^* (100)] (P) at 200 ° C. and an angular velocity of 100 rad / sec are determined by the following methods. It was measured.

Shear viscosity (eta ^*) were determined by measuring the angular velocity [omega (rad / sec)] variance of a shear viscosity at a measurement temperature of 200 ° C. (eta ^*) in the range of 0.02512 ≦ ω ≦ 100. For the measurement, a dynamic stress rheometer SR-5000 manufactured by Rheometrics was used, a 25 mmφ parallel plate was used as a sample holder, and the sample thickness was about 2.0 mm. The number of measurement points was 5 per ω digit. The amount of strain was appropriately selected within a range of 3 to 10% so that the torque in the measurement range could be detected and torque was not exceeded.

The sample used for the shear viscosity measurement is a press molding machine manufactured by Shinto Metal Industry, with a preheating temperature of 190 ° C., a preheating time of 5 minutes, a heating temperature of 190 ° C., a heating time of 2 minutes, a heating pressure of 100 kg weight / cm ² , and a cooling temperature. The measurement sample was produced by press molding to a thickness of 2 mm under the conditions of 20 ° C., cooling time of 5 minutes, and cooling pressure of 100 kg / cm ² .

<Methyl branch number and ethyl branch number>
It was determined by measuring a ¹³ C-NMR spectrum using an ECP500 type nuclear magnetic resonance apparatus (500 MHz) manufactured by JEOL Ltd.

A mixed solvent of ethylene polymer 250-400 mg, o-dichlorobenzene (special grade manufactured by Wako Pure Chemical Industries, Ltd.) and deuterated benzene (ISOTEC) in a commercially available quartz glass tube for NMR measurement having a diameter of 10 mm. 3 ml of o-dichlorobenzene: deuterated benzene = 5: 1 (v / v)) was added and heated at 120 ° C. to uniformly disperse the sample.
The number of integrations was 10,000 to 30,000.

The attribution of each absorption in the NMR spectrum is as follows: Chemical Domain No. 141 NMR-Review and Experiment Guide [I], p. It carried out according to 132-133. The number of methyl branches per 1000 carbon atoms constituting the polymer chain was calculated from the integrated intensity ratio of the absorption of methyl groups derived from methyl branches (19.9 ppm) to the integrated total of absorption appearing in the range of 5 to 45 ppm. The number of ethyl branches was calculated from the integrated intensity ratio of the absorption of ethyl groups (10.8 ppm) derived from ethyl branches to the integrated sum of absorptions appearing in the range of 5 to 45 ppm.
The peak of the main chain methylene (29.97 ppm) was used as the chemical shift standard.

<Zero shear viscosity (η ₀ )>
The zero shear viscosity (η ₀ ) (P) at 200 ° C. was determined by the following method.

At a measurement temperature of 200 ° C., the angular velocity ω (rad / sec) dispersion of the shear viscosity (η ^* ) was measured in the range of 0.02512 ≦ ω ≦ 100. For the measurement, a dynamic stress rheometer SR-5000 manufactured by Rheometrics was used, a 25 mmφ parallel plate was used as a sample holder, and the sample thickness was about 2.0 mm. The number of measurement points was 5 per ω digit. The amount of strain was appropriately selected within a range of 3 to 10% so that the torque in the measurement range could be detected and torque was not exceeded.

The sample used for the shear viscosity measurement is a press molding machine manufactured by Shinto Metal Industry, with a preheating temperature of 190 ° C., a preheating time of 5 minutes, a heating temperature of 190 ° C., a heating time of 2 minutes, a heating pressure of 100 kg weight / cm ² , and a cooling temperature. The measurement sample was produced by press molding to a thickness of 2 mm under the conditions of 20 ° C., cooling time of 5 minutes, and cooling pressure of 100 kg weight / cm ² .

The zero shear viscosity (η ₀ ) was calculated by fitting the following [Eq-4] Carreau model to an actually measured rheological curve [angular velocity (ω) dispersion of shear viscosity (η ^* )] by the nonlinear least square method.
η ^* = η ₀ [1+ (λω) ^a ] ^{(n-1) / a} [Eq-4]

  Here, λ is a parameter having a time dimension, and n is a power law index of the material. The fitting by the nonlinear least square method was performed so that d in [Eq-5] below was minimized.

［Ｅｑ−５］中、η_exp（ω）は実測のせん断粘度を表し、η_calc（ω）はＣａｒｒｅａｕモデルより算出したせん断粘度を表す。

In [Eq-5], η _exp (ω) represents the measured shear viscosity, and η _calc (ω) represents the shear viscosity calculated from the Carreau model.

<Weight average molecular weight (Mw)>
It measured as follows using GPC-viscosity detector (GPC-VISCO) GPC / V2000 by Waters.

  Shodex AT-G is used for the guard column, two AT-806 are used for the analytical column, a differential refractometer and a three-capillary viscometer are used for the detector, the column temperature is 145 ° C., and the mobile phase is As antioxidant, o-dichlorobenzene containing 0.3% by weight of BHT was used, the flow rate was 1.0 ml / min, and the sample concentration was 0.1% by weight. The standard polystyrene used was manufactured by Tosoh Corporation. In the molecular weight calculation, the actually measured viscosity was calculated from a viscometer and a refractometer, and the weight average molecular weight (Mw) was obtained from the actually measured universal calibration. The number average molecular weight (Mn) and the Z average molecular weight (Mz) were similarly determined.

<Molecular weight at the maximum weight fraction in the molecular weight distribution curve (peak top M)>
The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve was measured as follows using a gel permeation chromatograph alliance GPC2000 (high temperature size exclusion chromatograph) manufactured by Waters.

Analysis software: Chromatography data system Empower (Waters)
Column; TSKgel GMH ₆ -HT × 2 + TSKgel GMH ₆ -HTL × 2 (inner diameter 7.5 mm × length 30 cm, Tosoh Corporation)
Mobile phase: o-dichlorobenzene (Wako Pure Chemicals special grade reagent)
Detector: Differential refractometer (built-in device)
Column temperature: 140 ° C
Flow rate: 1.0 mL / min Injection volume: 500 μL
Sampling time interval; 1 second Sample concentration; 0.15% (w / v)
Molecular weight calibration; monodisperse polystyrene (Tosoh Corp.) / Molecular weight 495 to 20.6 million Crubisic, P.M. Rempp, H.M. Benoit, J.M. Polym. Sci. , B5 , 753 (1967), a molecular weight distribution curve was prepared in terms of standard polystyrene molecular weight according to the procedure of general-purpose calibration. The molecular weight at the maximum weight fraction was calculated from this molecular weight distribution curve.

<Intrinsic viscosity [η]>
About 20 mg of a measurement sample was dissolved in 15 ml of decalin, and the specific viscosity η _sp was measured in an oil bath at 135 ° C. After adding 5 ml of decalin solvent to the decalin solution for dilution, the specific viscosity η _sp was measured in the same manner. This dilution operation was further repeated twice, and the value of η _sp / C when the concentration (C) was extrapolated to 0 was determined as the intrinsic viscosity [η] (unit: dl / g).
[Η] = lim (η _sp / C) (C → 0)

[Method for producing foam and measurement of foam]
1.0 wt% of 1470T (Takehara Chemical Co., Ltd., talc content 70 wt%), which is a talc masterbatch for polyolefins, was added to the uncrosslinked foamed ethylene polymer as a cell nucleating agent. The sample was weighed with an injection device of J180ELIII-MuCell injection molding machine manufactured by Nippon Steel Works while maintaining the cylinder internal pressure at 10 MPa, and at the same time carbon dioxide in a supercritical state was injected into the cylinder at an injection pressure of 16 MPa to mix with the resin. Got. The obtained mixture was extruded into the atmosphere under conditions of an extrusion amount of 95 g and an extrusion time of 12 seconds to obtain a foam.

0.80 part by weight of dicumyl peroxide (manufactured by NOF Corporation) as an organic oxide and azodicarbonamide (manufactured by Sankyo Kasei Co., Ltd.) 15 as a pyrolytic foaming agent with respect to 100 parts by weight of a crosslinked foamed ethylene polymer The parts by weight were melt-kneaded in a lab plast mill (resin temperature 125 ° C., rotation speed 40 rpm, 3 minutes) manufactured by Toyo Seiki Seisakusho. The obtained resin composition was press-molded using a press molding machine (heating temperature: 125 ° C., heating time: 3 minutes, press pressure: 100 kg / cm ² ) manufactured by Shinto Metal Industries, Ltd., to produce a sheet having a thickness of 2 mm. This sheet was put into an oven set at 235 ° C., crosslinked and foamed to obtain a foam.

<Foaming ratio>
The specific gravity of the sample before foaming and the foam was measured with a hydrometer and determined by the following formula.
Foaming ratio = specific gravity of sample before foaming / specific gravity of foam

<Foamed state, appearance>
The appearance of the foam sheet was visually evaluated.

<Strength at break, elongation at break>
A test piece having a length of 40 mm, a width of 10 mm, and a thickness of 2 mm was cut out from the obtained foam, and the strength at break and the elongation at break were determined by a tensile test of the test piece. The measurement conditions of the tensile test are as follows.
Tensile testing machine: Tensilon universal testing machine RTG1310 manufactured by A & D
Measurement temperature: 23 ° C
Test speed: 300 mm / min.
Distance between chucks: 30mm

[Catalyst Synthesis Example 1] Synthesis of dimethylsilylene (cyclopentadienyl) (3-n-propylcyclopentadienyl) zirconium dichloride (A1)
<Step 1> Synthesis of chloro (cyclopentadienyl) dimethylsilane To 14.3 g (110 mmol) of dimethylsilyl dichloride, 100 ml of tetrahydrofuran (THF) was added and cooled to -78 ° C. 38.7 ml (77.4 mmol) of 2M-sodium cyclopentadienide in THF was added dropwise over 30 minutes, the temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. Concentration under reduced pressure was performed, and sodium chloride was removed by filtration. After washing with hexane, hexane in the filtrate was distilled under reduced pressure, and the resulting chloro (cyclopentadienyl) dimethylsilane was used in the next step.

<Step 2> Synthesis of dimethylsilyl (3-n-propylcyclopentadienyl) (cyclopentadienyl) 100 ml of THF was added to 2.16 g (20 mmol) of n-propylcyclopentadiene and cooled to -78 ° C. 1.53 M-n-butyllithium / hexane solution (13.3 ml, 22 mmol) was slowly added dropwise, and the mixture was stirred at room temperature for 3 hours. The reactor was cooled again to −78 ° C., and 3.97 g (25 mmol) of chloro (cyclopentadienyl) dimethylsilane was dissolved in 20 ml of THF and added dropwise to the reactor. After stirring at room temperature for 18 hours, the completion of the reaction was confirmed by TLC. The reaction was stopped by adding water at 0 ° C. Extraction was performed with hexane, and the organic layer was washed with saturated brine. After drying with magnesium sulfate, the solution obtained after filtration was concentrated under reduced pressure. Purification was performed by silica gel column chromatography (eluent: hexane: triethylamine = 98: 2 v / v) and vacuum distillation to obtain 1.73 g of dimethylsilyl (3-n-propylcyclopentadienyl) (cyclopentadienyl). (Yield 38%) was obtained.
^The target product was identified by ¹ H-NMR and GC-MS.
¹ H-NMR (CDCl ₃ , TMS standard); 7.0-6.0 (br, 7H), 3.0 (s, 1H), 2.9 (s, 1H), 2.3 (m, 2H) ), 1.6 (m, 2H), 0.9 (t, 3H), 0.1 (t, 3H), -0.2 ppm (s, 3H)
GC-MS; 230 (MS)

<Step 3> Synthesis of dimethylsilylene (3-n-propylcyclopentadienyl ) (cyclopentadienyl) zirconium dichloride (A1) Dimethylsilyl (3-n-propylcyclopentadienyl) (cyclopentadienyl) 90 g (3.9 mmol) was dissolved in 40 ml of diethyl ether. After cooling to −78 ° C., 5.09 ml (8.0 mmol) of 1.57 M-n-butyllithium / hexane solution was added dropwise. The temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. The solution was concentrated under reduced pressure and washed with 13 ml of hexane three times. The obtained white solid was suspended in 50 ml of hexane, and 820 mg (3.5 mmol) of zirconium tetrachloride was added at −78 ° C. The temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. Filter and wash with hexane to remove salts. The filtrate was concentrated under reduced pressure and washed with pentane. The obtained solid was dried under reduced pressure to obtain 210 mg (yield 14%) of dimethylsilylene (3-n-propylcyclopentadienyl) (cyclopentadienyl) zirconium dichloride (A1).
^The target product was identified by ¹ H-NMR and FD-MS.
¹ H-NMR (CDCl ₃ , TMS standard); 7.1-6.9 (m, 2H), 6.6 (s, 1H), 6.0-5.8 (m, 3H), 5.5 (S, 1H), 2.6 (m, 2H), 1.5 (m, 2H), 0.9 (t, 3H), 0.8-0.7 ppm (d, 6H)
FD-MS; 388 (MS)

[Catalyst Synthesis Example 2] Synthesis of dimethylsilylene (cyclopentadienyl) (3-n-butylcyclopentadienyl) zirconium dichloride (A2)
<Step 1> Synthesis of (3-n-butylcyclopentadienyl) chlorodimethylsilane 50 ml of THF was added to 30.1 g (61.5 mmol) of 25 wt% -butylcyclopentadiene / THF solution. The solution was cooled to 0 ° C., and 38.4 ml (58.4 mol) of a 1.52 M-n-butyllithium / hexane solution was added dropwise. The mixture was stirred at room temperature for 2 hours, and added dropwise to 14.3 g (110 mmol) of dimethylsilyl dichloride and 50 ml of THF at −78 ° C. The temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. Concentration was performed under reduced pressure, and insoluble materials were removed by filtration. After washing with hexane, the filtrate was distilled under reduced pressure. Distillation under reduced pressure was performed to obtain 8.09 g (yield 64%) of (3-n-butylcyclopentadienyl) chlorodimethylsilane.
The target product was identified by GC-MS.
GC-MS; 214 (MS)

<Step 2> Synthesis of dimethylsilyl (3-n-butylcyclopentadienyl) (cyclopentadienyl) 50 ml of THF was added to 8.8 ml (16.6 mmol ) of 2M-sodium cyclopentadienide in THF, and -78 ° C. Cooled to. 1.89 g (8.8 mmol) of (3-n-butylcyclopentadienyl) chlorodimethylsilane was dissolved in 20 ml of THF and added dropwise to the reactor. After stirring at room temperature for 2 hours, the mixture was stirred at 50 ° C. for 2 hours. The completion of the reaction was confirmed by TLC, and water was added at 0 ° C. to stop the reaction. Extraction was performed with hexane, and the organic layer was washed with saturated brine. After drying with magnesium sulfate, the solution obtained after filtration was concentrated under reduced pressure. Distillation under reduced pressure was performed to obtain 1.07 g (yield 50%) of dimethylsilyl (3-n-butylcyclopentadienyl) (cyclopentadienyl).
^The target product was identified by ¹ H-NMR and GC-MS.
¹ H-NMR (CDCl ₃ , TMS standard); 7.0-6.0 (br, 7H), 3.2 (d, 1H), 2.9 (d, 1H), 2.3 (t, 2H) ), 1.4 (m, 4H) 0.9 (t, 3H), 0.1 (t, 3H), -0.2 ppm (s, 3H)
GC-MS; 244 (MS)

<Step 3> Synthesis of dimethylsilylene (3-n-butylcyclopentadienyl ) (cyclopentadienyl) zirconium dichloride (A2) Dimethylsilyl (3-n-butylcyclopentadienyl) (cyclopentadienyl) 58 g (2.38 mmol) was dissolved in 30 ml of diethyl ether. The mixture was cooled to −78 ° C., and 3.16 ml (4.99 mmol) of a 1.57 M-n-butyllithium / hexane solution was added dropwise. The temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. The solution was concentrated under reduced pressure and washed 3 times with 6 ml of hexane. The obtained white solid was suspended in 60 ml of hexane, and 500 mg (2.15 mmol) of zirconium tetrachloride was added at −78 ° C. The temperature was gradually raised, and the mixture was stirred at room temperature for 24 hours. Filter and wash with hexane to remove salts. The filtrate was concentrated under reduced pressure to obtain 510 mg of a crude product. The solid obtained after washing with diethyl ether and pentane was dried under reduced pressure to obtain 190 mg (yield 20%) of dimethylsilylene (3-n-butylcyclopentadienyl) (cyclopentadienyl) zirconium dichloride (A2). It was.
^The target product was identified by ¹ H-NMR and FD-MS.
¹ H-NMR (CDCl ₃ , TMS standard); 6.9 (d, 2H), 6.6 (s, 1H), 5.9 (t, 3H), 5.5 (s, 1H), 2. 6 (m, 2H), 1.4 (m, 2H), 1.3 (m, 2H), 0.9 (t, 3H), 0.8 ppm (m, 3H)
FD-MS; 404 (MS)

[Catalyst Synthesis Example 3] Synthesis of isopropylidene (cyclopentadienyl-2,7-di-t-butyl-9-fluorenyl) zirconium dichloride (B1) Synthesis based on the method described in JP-A-4-69394 did.

[Example 1]
Preparation of solid component (S) 10 kg of silica (SiO ₂ ; average particle size 12 μm) dried at 250 ° C. for 10 hours under a nitrogen atmosphere was suspended in 66.5 liters of toluene in a reactor with an internal volume of 200 liters. After becoming cloudy, it was cooled to 0-5 ° C. 19.8 liters of a toluene solution of methylalumoxane (3.575 mmol / mL in terms of Al atoms) was diluted with 30.2 liters of toluene. Diluted toluene solution of methylalumoxane was added dropwise to this suspension over 1 hour. At this time, the temperature in the system was kept at 0 to 5 ° C. Subsequently, the mixture was reacted at 0 to 5 ° C. for 30 minutes, then heated to 95 to 100 ° C. over about 1.5 hours, and then reacted at 95 to 100 ° C. for 4 hours. Thereafter, the temperature was lowered, and the supernatant was removed by decantation. The solid component thus obtained was washed 4 times with toluene. Toluene was added to make a total volume of 140 liters, and a toluene slurry of solid component (S) was prepared.
A part of the obtained solid component (S) was collected and examined for concentration. As a result, the slurry concentration was 98.04 g / L and the Al concentration was 0.471 mol / L.

Preparation of solid catalyst component (X-1) A reactor equipped with a stirrer with an internal volume of 150 liters was charged with toluene and a toluene slurry of solid component (S) (1575 g of solid component) under a nitrogen atmosphere, and the total amount Was adjusted to 33 liters. Next, 3.58 g (9.18 mmol in terms of Zr atom) of the metallocene compound (A1) obtained in Catalyst Synthesis Example 1 and the metallocene compound obtained in Catalyst Synthesis Example 3 in a 2 liter glass reactor in a nitrogen atmosphere (B1) 15.83 g (29.06 mmol in terms of Zr atom) was collected (molar ratio of (A1) / (B1) = 24/76), dissolved in 2.0 liters of toluene, and pumped to the reactor. After pumping, the reaction is allowed to proceed at an internal temperature of 73 to 76 ° C. for 2 hours, the supernatant is removed by decantation, the solid catalyst component is washed three times with hexane, and hexane is added to make a total volume of 25 liters. A hexane slurry of (X-1) was prepared.

Preparation of pre-polymerization catalyst component (XP-1) Subsequently, the hexane slurry of the solid catalyst component (X-1) obtained above was cooled to 10.8 ° C., and then the chemical stud 2500 (Sanyo Chemical Industries) was used as a surfactant. 15.9 g of a hexane solution was pumped into the reactor, and then 1.4 mol of diisobutylaluminum hydride (DiBAl-H) was added. Further, ethylene was continuously fed into the system for several minutes under normal pressure. During this time, the temperature in the system was maintained at 10 to 15 ° C., and then 103 mL of 1-hexene was added. After the addition of 1-hexene, ethylene supply was started at 1.5 kg / h, and prepolymerization was performed at a system temperature of 32 to 37 ° C. After 85 minutes from the start of the prepolymerization, 52 mL of 1-hexene was added, and also after 155 minutes, 52 mL of 1-hexene was added. After 217 minutes from the start of the prepolymerization, the ethylene supply reached 4643 g, and the ethylene supply was stopped. . Thereafter, the supernatant was removed by decantation and the solid catalyst component was washed four times with hexane, and then hexane was added to make a total volume of 25 liters.

  Next, a hexane solution of Chemistad 2500 (63.8 g) was pumped into the reactor at a system temperature of 34 to 36 ° C., and then kept at 34 to 36 ° C. for 2 hours to prepare Chemistad 2500 as a prepolymerized catalyst component. Was supported. Thereafter, the supernatant was removed by decantation, and the prepolymerized catalyst component was washed four times with hexane.

Next, 25 liters of hexane slurry of the above prepolymerization catalyst (6456 g as a solid prepolymerization catalyst) was transferred to a 43 liter internal evaporator with a stirrer under a nitrogen atmosphere. After the liquid transfer, the inside of the dryer was depressurized to -68 kPaG over about 60 minutes, and when it reached -68 kPaG, vacuum drying was performed for about 4.3 hours to remove volatile components of hexane and the prepolymerized catalyst. Further, the pressure was reduced to −100 kPaG, and when the pressure reached −100 kPaG, vacuum drying was performed for 8 hours to obtain a prepolymerized catalyst component (XP-1) in which 3 g of polymer was polymerized per 1 g of the solid catalyst component.
A part of the obtained prepolymerized catalyst component (XP-1) was dried and the composition was examined. As a result, 0.5 mg of Zr atom was contained per 1 g of the solid catalyst component.

In a fluidized bed gas phase polymerization reactor having a polymerization internal volume of 1.7 m ³ , an ethylene / 1-hexene copolymer was produced using a prepolymerization catalyst (XP-1).

  In accordance with the conditions shown in Table 1, the prepolymerization catalyst component (XP-1) was continuously fed into the reactor, the total pressure was 2.0 MPa · G, the ethylene partial pressure was 1.2 MPa · abs (absolute pressure), the polymerization temperature. Ethylene, nitrogen and 1-hexene were continuously fed at 80 ° C. and a gas linear velocity of 0.8 m / sec in the reactor. The polymerization reaction product was continuously withdrawn from the polymerization reactor and dried with a drying apparatus to obtain an ethylene / 1-hexene copolymer.

To the resulting ethylene / 1-hexene copolymer, 0.1% by weight of Irganox 1076 (manufactured by Ciba Specialty Chemicals) and 0.1% by weight of Irgafos 168 (manufactured by Ciba Specialty Chemicals) were added as a heat-resistant stabilizer. Using a 20 mmφ extruder with a biaxial different direction manufactured by Seisakusho, melt kneading was performed under the conditions of a set temperature of 200 ° C. and a screw rotation speed of 100 rpm, and then extruded into a strand shape and cut to obtain pellets.
Physical properties were measured using the obtained pellets as measurement samples. The results are shown in Table 2.

[Example 2]
Preparation of solid catalyst component (X-2) In the preparation of the solid catalyst component (X-1) of Example 1, the reaction ratio of the metallocene compound (A1) and the metallocene compound (B1) was (A1) / (B1) = 24. The solid catalyst component (X-2) was prepared in the same manner as in the preparation of the solid catalyst component (X-1), except that / 76 (molar ratio) was changed to (A1) / (B1) = 18/82 (molar ratio). A hexane slurry was prepared.

Preparation of prepolymerization catalyst component (XP-2) Preparation of prepolymerization catalyst component (XP-1) was carried out except that solid catalyst component (X-2) was used instead of solid catalyst component (X-1). A prepolymerized catalyst component (XP-2) was obtained in the same manner as in the preparation of the polymerization catalyst component (XP-1).
When the composition of the obtained prepolymerization catalyst component (XP-2) was examined, 0.50 mg of Zr atoms were contained per 1 g of the solid catalyst component.

In the polymerization of Polymerization Example 1, an ethylene / 1-hexene copolymer was obtained in the same manner as in Example 1 except that the catalyst components and the polymerization conditions were changed to the conditions shown in Table 1.

A measurement sample was prepared in the same manner as in Example 1 using the obtained ethylene / 1-hexene copolymer.
Table 2 shows the results of physical property measurements using the above samples, Table 3 shows the results of non-crosslinked foam molding, and Table 4 shows the results of cross-linked foam molding.

[Example 3]
Preparation of Solid Catalyst Component (X-3) In the preparation of the solid catalyst component (X-1) of Example 1, the reaction ratio of the metallocene compound (A1) and the metallocene compound (B1) was (A1) / (B1) = 24. / 76 (molar ratio) to (A1) / (B1) = 28/72 (molar ratio) in the same manner as the solid catalyst component (X-1) hexane of the solid catalyst component (X-3) A slurry was prepared.

Preparation of prepolymerization catalyst component (XP-3) Preparation of prepolymerization catalyst component (XP-1) was carried out except that solid catalyst component (X-3) was used instead of solid catalyst component (X-1). Preliminary polymerization catalyst component (XP-3) was obtained in the same manner as in the preparation of polymerization catalyst component (XP-1).
When the composition of the obtained prepolymerization catalyst component (XP-3) was examined, 0.50 mg of Zr atoms were contained per 1 g of the solid catalyst component.

In the polymerization of Polymerization Example 1, an ethylene / 1-hexene copolymer was obtained in the same manner as in Example 1 except that the catalyst components and the polymerization conditions were changed to the conditions shown in Table 1.

A measurement sample was prepared in the same manner as in Example 1 using the obtained ethylene polymer.
Table 2 shows the results of physical property measurements using the above samples, Table 3 shows the results of non-crosslinked foam molding, and Table 4 shows the results of cross-linked foam molding.

[Example 4]
Preparation of solid catalyst component (X-4) To a reactor equipped with a stirrer having an internal volume of 150 liters, 50.1 liters of toluene and a toluene slurry of solid component (S) prepared in Example 1 (in solid components) 1265 g) was charged. Next, in a 2-liter glass reactor, under a nitrogen atmosphere, 5.72 g (14.65 mmol in terms of Zr atom) of the metallocene compound (A2) obtained in Catalyst Synthesis Example 2 and 9.00 g (Zr) of the metallocene compound (B1). (16.52 mmol in terms of atoms) was collected in a molar ratio of (A2) / (B1) = 40/60, dissolved by adding 2.0 liters of toluene, and then pumped to the reactor equipped with a stirrer. did. After pumping, the mixture is reacted at an internal temperature of 20 to 25 ° C. for 1 hour, the supernatant liquid is removed by decantation, hexane is added to wash the solid catalyst component twice, and hexane is added again to make the total volume 50 liters. A hexane slurry of the catalyst component (X-4) was prepared.

Preparation of prepolymerized catalyst component (XP-4) Subsequently, the hexane slurry of the solid catalyst component (X-4) obtained above was cooled to 10.0 ° C., and then ethylene was continuously introduced into the system under normal pressure. Feed for several minutes. During this time, the temperature in the system was maintained at 10 to 15 ° C. Then 2.7 mol of diisobutylaluminum hydride (DiBAl-H) and 84 mL of 1-hexene were added. After adding 1-hexene, ethylene supply was started at 1.82 kg / h, and prepolymerization was performed at a system temperature of 32 to 37 ° C. 58 minutes after the start of prepolymerization, 43.0 mL of 1-hexene was added, and 43.0 mL of 1-hexene was added 111 minutes later, and ethylene supply reached 3827 g 153 minutes after the start of prepolymerization. By the way, ethylene supply was stopped. Thereafter, the supernatant was removed by decantation, and the solid catalyst component was washed three times with hexane, and then hexane was added again to make the total volume 66 liters.

  Next, the system temperature is set to 34 to 36 ° C., and a hexane solution of Chemistad 2500 (13.1 g) is pumped to the reactor. Supported. Thereafter, the supernatant liquid was removed by decantation, and the prepolymerized catalyst was washed four times with hexane.

Next, 25 liters of hexane slurry of the above prepolymerization catalyst (5269 g as a solid prepolymerization catalyst) was transferred to a 43 liter evaporative dryer with a stirrer under a nitrogen atmosphere. After the liquid transfer, the inside of the dryer was depressurized to -65 kPaG over about 3.5 hours, and when it reached -65 kPaG, it was vacuum-dried for about 4.0 hours to remove hexane and volatile components of the prepolymerized catalyst. The pressure was further reduced to −100 kPaG, and when the pressure reached −100 kPaG, vacuum drying was performed for 6 hours to obtain a prepolymerized catalyst component (XP-4) in which 3 g of polymer was polymerized per 1 g of the solid catalyst component.
A part of the obtained prepolymerized catalyst component (XP-4) was dried and the composition was examined. As a result, 0.50 mg of Zr atom was contained per 1 g of the solid catalyst component.

In the polymerization of Polymerization Example 1, an ethylene / 1-hexene copolymer was obtained in the same manner as in Example 1 except that the catalyst components and the polymerization conditions were changed to the conditions shown in Table 1.

A measurement sample was prepared in the same manner as in Example 1 using the obtained ethylene / 1-hexene copolymer.
Table 2 shows the results of physical property measurements using the above samples, Table 3 shows the results of non-crosslinked foam molding, and Table 4 shows the results of cross-linked foam molding.

[Comparative Example 1]
An ethylene / 1-hexene copolymer (trade name: Evolue SP2040) obtained by the gas phase polymerization method commercially available from Prime Polymer Co., Ltd. was obtained by using product pellets as measurement samples. The results of the physical property measurement are shown in Table 2, and the results of non-crosslinking foam molding are shown in Table 3.

In Comparative Example 1, MT / [η ^* (1.0)] is smaller than the lower limit value of Claim 1 (III), and zero shear viscosity (η ₀ ) is larger than the upper limit value of Claim 1 (V). For this reason, the foaming ratio of a foam is low, there are many foam breaks, and a bubble is non-uniform | heterogenous. Moreover, since η ^* (100) / η ^* (1.0) is large, the cylinder back pressure during extrusion is high and the extrusion characteristics are poor.

[Comparative Example 2]
Polyethylene (trade name: Mirason 11) obtained by the high pressure radical polymerization method commercially available from Prime Polymer Co., Ltd. was measured using product pellets. The results of the physical property measurement are shown in Table 2, and the results of non-crosslinking foam molding are shown in Table 3.

  In Comparative Example 2, the sum (A + B) of the number of methyl branches [A / (1000C)] and the number of ethyl branches [B / (1000C)] is larger than the upper limit of claim 1 (IV). For this reason, the breaking strength and elongation at break of the foam are inferior.

[Comparative Example 3]
The ethylene / 1-octene copolymer (trade name: Affinity PF1140) obtained by a solution polymerization method commercially available from Dow Chemical Company was evaluated for physical properties using a product pellet as a measurement sample. The results are shown in Table 2.

In Comparative Example 3, MT / [η ^* (1.0)] is smaller than the lower limit value of Claim 1 (III), and the zero shear viscosity (η ₀ ) is larger than the upper limit value of Claim 1 (V). For this reason, it is estimated that the foaming ratio of a foam is low and it is inferior to a foaming state.

[Comparative Example 4]
A product pellet of polyethylene (trade name: Mirason 14P) obtained by the high pressure radical polymerization method commercially available from Prime Polymer Co., Ltd. was used as a measurement sample. Table 2 shows the results of physical property measurements, Table 3 shows the results of non-crosslinked foam molding, and Table 4 shows the results of cross-linked foam molding.

  In Comparative Example 4, the sum (A + B) of the number of methyl branches [A / (1000C)] and the number of ethyl branches [B / (1000C)] is larger than the upper limit of claim 1 (IV). For this reason, the breaking strength and elongation at break of the foam are inferior.

[Comparative Example 5]
A product pellet of low density polyethylene (trade name: Excellen GMH CU1002) having a long chain branching by a metallocene catalyst commercially available from Sumitomo Chemical was used as a measurement sample. The results of the physical property measurement are shown in Table 2, and the results of non-crosslinking foam molding are shown in Table 3.

In Comparative Example 5, MT / [η ^* (1.0)] is smaller than the lower limit value of Claim 1 (III), and zero shear viscosity (η ₀ ) is larger than the upper limit value of Claim 1 (V). For this reason, the foaming ratio of a foam is low, there are many foam breaks, and a bubble is non-uniform | heterogenous.

[Comparative Example 6]
[Preparation of solid component (S2)]
10 kg of silica (SiO ₂ : average particle size 12 μm) dried at 250 ° C. for 10 hours under a nitrogen atmosphere was suspended in 90.5 L of toluene in a reactor with an internal volume of 260 L, and then cooled to 0 to 5 ° C. did. To this suspension, 45.5 L of a toluene solution of methylalumoxane (3.0 mmol / mL in terms of Al atom) was added dropwise over 30 minutes. At this time, the temperature in the system was kept at 0 to 5 ° C. Subsequently, the mixture was reacted at 0 to 5 ° C. for 30 minutes, then heated to 95 to 100 ° C. over about 1.5 hours, and then reacted at 95 to 100 ° C. for 4 hours. Thereafter, the temperature was lowered to room temperature, and the supernatant was removed by decantation. The solid component thus obtained was washed twice with toluene, and then toluene was added to a total volume of 129 L to prepare a toluene slurry of the solid component (S2). A part of the obtained solid component was collected and examined for concentration. As a result, the slurry concentration was 137.5 g / L and the Al concentration was 1.1 mol / L.

Preparation of solid catalyst component (X-5) 50 mL of toluene was placed in a 200 mL glass flask purged with nitrogen, and the toluene slurry of the solid component (S2) prepared above was added with stirring (2.0 g in terms of solid part). I entered. Next, 32.5 mL of a toluene solution (0.002 mmol / mL in terms of Zr atom) of dimethylsilylene bis (cyclopentadienyl) zirconium dichloride (A3) mixed in advance and isopropylidene (cyclopentadienyl) (fluorenyl) zirconium A mixed solution of 7.23 mL of a toluene solution of dichloride (B2) (0.001 mmol / mL in terms of Zr atom) was dropped, and the mixture was reacted at room temperature for 1 hour. Thereafter, the supernatant was removed by decantation and washed twice with decane to obtain a decane slurry (solid catalyst component X-5). The mixing molar ratio of the metallocene compound (A3) and (B2) during the preparation of the solid catalyst component is (A3) / (B2) = 90/10. Further, when a portion of the resulting decane slurry of the solid catalyst component (X-5) was collected to examine the concentration, the Zr concentration was 0.065 mg / mL and the Al concentration was 3.77 mg / mL.

Polymerization Purified heptane (500 mL) was placed in a 1-liter SUS autoclave sufficiently purged with nitrogen, ethylene was circulated, and the liquid phase and gas phase were saturated with ethylene. Next, after replacing the inside of the system with a hydrogen-ethylene mixed gas (hydrogen concentration: 0.06 vol%), 1 mL of 1-hexene, 0.375 mmol of triisobutylaluminum, 0.01 mmol of a solid catalyst in terms of zirconium Ingredient (X-5) was charged in this order. The temperature was raised to 70 ° C., and polymerization was carried out at 0.78 MPa · G for 90 minutes. The obtained polymer was vacuum-dried for 10 hours to obtain 92.9 g of an ethylene / 1-hexene copolymer.

To prepare a measurement sample, Irganox 1076 (manufactured by Ciba Specialty Chemicals) 0.1% by weight and Irgafos168 (manufactured by Ciba Specialty Chemicals) 0.1% by weight were added to the obtained ethylene polymer as a heat-resistant stabilizer. Using a Laboplast mill manufactured by Seiki Seisakusho, melt kneading was performed for 5 minutes at a resin temperature of 180 ° C. and a rotation speed of 50 rpm. Further, this molten polymer was cooled using a press molding machine manufactured by Shindo Metal Industries under the conditions of a cooling temperature of 20 ° C., a cooling time of 5 minutes, and a cooling pressure of 100 kg / cm ² . Table 2 shows the results of physical properties measured using the above samples, and Table 4 shows the results of cross-linked foam molding. In Comparative Example 6, the molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve is smaller than the lower limit value of claim 1 (VI). For this reason, the breaking strength of the foam is inferior.

  The ethylene polymer for foam molding of the present invention has sufficiently high melt tension, excellent extrusion characteristics, and mechanical strength compared to conventional ethylene polymers produced with Ziegler-Natta catalysts or metallocene catalysts. Especially excellent. Therefore, the foam obtained from the ethylene-based polymer for foam molding of the present invention or the resin composition for foam molding containing the polymer has a high expansion ratio, a good foamed state, and sufficient mechanical strength. Therefore, it is suitably used for floor materials, building materials, packaging and packing materials, automobile interior materials, daily goods, mats, sheets, sports equipment, and the like.

Claims (5)

Ethylene homopolymer, or copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms, and satisfying the following requirements (I) to (VI) simultaneously: A foam obtained from a polymer.
(I) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is in the range of 0.1 to 10 g / 10 min.
(II) The density (d) is in the range of 875 to 970 kg / m ³ .
(III) Ratio [MT / η ^* (1) of melt tension [MT (g)] at 190 ° C. and shear viscosity [η ^* (1.0) (P)] at 200 ° C. and an angular velocity of 1.0 rad / sec. 0.0)] is in the range of 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ g / P.
(IV) The sum [(A + B) (/ 1000C)] of the number of methyl branches A (/ 1000C) and the number of ethyl branches B (/ 1000C) per 1000 carbon atoms measured by ¹³ C-NMR is 1.8. It is as follows.
(V) Zero shear viscosity η ₀ (P) at 200 ° C. and a weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) satisfy the following relational expression.
0.10 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 60 × 10 ⁻³¹ × Mw ^6.8
(VI) The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is in the range of 1.0 × 10 ^{4.20 to} 1.0 × 10 ^4.60 . The foam-forming ethylene polymer foam according to claim 1, characterized by further satisfying the following requirement (VII) and (VIII).
(VII) The intrinsic viscosity [η] (dl / g) measured in decalin at 135 ° C. and the weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) Eq-1] is satisfied.
0.80 × 10 ⁻⁴ × Mw ^0.776 ≦ [η] ≦ 1.65 × 10 ⁻⁴ × Mw ^0.776 [Eq-1]
(VIII) Shear viscosity [η ^* (100)] (P) at 200 ° C. and angular velocity 100 rad / sec, and Shear viscosity [η ^* (1.0)] (P) at 200 ° C. and angular velocity 1.0 rad / sec The ratio [η ^* (100) / η ^* (1.0)] is in the range of 0.04 to 0.40. An ethylene homopolymer, or a copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms, and simultaneously satisfying the following requirements (I) to (VI): A resin composition for foam molding comprising a thermoplastic resin other than the ethylene polymer for foam molding.
(I) The melt flow rate (MFR) at a load of 2.16 kg at 190 ° C. is in the range of 0.1 to 10 g / 10 min.
(II) The density (d) is in the range of 875 to 970 kg / m ³ .
(III) Ratio [MT / η ^* (1 ) of melt tension [MT (g)] at 190 ° C. and shear viscosity [η ^* (1.0) (P)] at 200 ° C. and an angular velocity of 1.0 rad / sec. 0.0)] is in the range of 1.00 × 10 ^{−4 to} 7.00 × 10 ⁻⁴ g / P.
(IV) The sum [(A + B) (/ 1000C)] of the number of methyl branches A (/ 1000C) and the number of ethyl branches B (/ 1000C) per 1000 carbon atoms measured by ¹³ C-NMR is 1.8. It is as follows.
(V) Zero shear viscosity η ₀ (P ) at 200 ° C. and a weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) satisfy the following relational expression.
0.10 × 10 ⁻³¹ × Mw ^6.8 ≦ η ₀ ≦ 60 × 10 ⁻³¹ × Mw ^6.8
(VI) The molecular weight (peak top M) at the maximum weight fraction in the molecular weight distribution curve obtained by GPC measurement is in the range of 1.0 × 10 ^{4.20 to} 1.0 × 10 ^4.60 . The resin composition for foam molding according to claim 3, wherein the ethylene polymer for foam molding further satisfies the following requirements (VII) and (VIII).
(VII) The intrinsic viscosity [η] (dl / g) measured in decalin at 135 ° C. and the weight average molecular weight (Mw) measured by GPC-viscosity detector method (GPC-VISCO) Eq-1] is satisfied.
0.80 × 10 ^-Four × Mw ^0.776 ≦ [η] ≦ 1.65 × 10 ^-Four × Mw ^0.776 [Eq-1]
(VIII) Shear viscosity [η at 200 ° C. and angular velocity of 100 rad / sec. ^* (100)] (P) and shear viscosity [η at an angular velocity of 1.0 rad / sec at 200 ° C. ^* (1.0)] Ratio to (P) [η ^* (100) / η ^* (1.0)] is in the range of 0.04 to 0.40. 請 Motomeko 3 or foam obtainable from the foamed molding resin composition according to 4.