JP5648463B2 - Polyethylene pipe - Google Patents

Description

  The present invention relates to a polyethylene pipe using a polyethylene polymer. More specifically, the present invention relates to a polyethylene pipe suitable for gas transport pipes and water supply / drainage pipes because of excellent surface smoothness during extrusion molding and excellent balance between rigidity and long-term creep property.

  Polyethylene resin has good mechanical properties such as rigidity, impact resistance, ESCR, and elongation characteristics, and is excellent in corrosion resistance and chemical resistance, and is therefore used as a pipe material for gas transportation or water supply / drainage.

  However, recently, from the viewpoint of consideration of environmental issues and ease of handling, there is a high demand for reducing the thickness and weight of pipes. Sufficient strength can be obtained even when the wall thickness is reduced, and long-term creep properties such as ESCR Also, an excellent polyethylene resin is desired. Further, from the viewpoint of product productivity, a polyethylene resin is desired that has a low load during molding, can increase the production rate, and has good surface smoothness of the obtained pipe.

  Generally, in order to maintain product strength by reducing the wall thickness, it is necessary to increase the rigidity (that is, the density of polyethylene). However, long-term creep has a contradictory relationship with the density. If the density is increased, there will be a problem that long-term creep properties such as ESCR are insufficient. In order to reduce the extrusion load, it is basically necessary to increase the MFR. However, by increasing the MFR, melt dripping occurs during extrusion molding, and pipe formability deteriorates and long-term creep occurs. There arises a problem that the performance is lowered. Therefore, it has been difficult to obtain a polyethylene pipe satisfying all of the surface smoothness, rigidity, and long-term creep property by the conventional technique.

  In recent years, for the purpose of solving the above problems, a method of improving the balance between rigidity and long-term creep property by separately producing a low molecular weight component and a high molecular weight component and introducing a comonomer only into the high molecular weight component (Patent Document 1). See), a method of improving both surface gloss and durability stability by blending linear polyethylene having specific physical properties with low-density polyethylene under high pressure (see Patent Document 2), and polyethylene resin having specific physical properties. A method of improving extrusion moldability by adding a fluorine-based elastomer and achieving both long-term creep properties and good surface smoothness (Patent Document 3) has been disclosed, but surface smoothness, rigidity, long-term creep properties are disclosed. I have not yet satisfied all of the above.

JP 2000-109521 A JP 2008-285604 A JP 2000-143892 A

  In view of the present situation, the present invention is to provide a polyethylene pipe that has good surface smoothness during extrusion molding and excellent balance between rigidity and long-term creep property, and is suitable for a gas transport pipe or a water supply / drainage pipe. .

As a result of intensive studies on the above problems, the inventors of the present invention have a density of 925 to 970 kg / m ³ or less, an MFR of 0.05 to 1 g / 10 min, two peaks are observed in the GPC measurement, and a number average molecular weight in a specific range. (Mn) and an ethylene polymer having a molecular weight distribution (Mw / Mn), a component having a Mn of 100,000 or more obtained by molecular weight fractionation at a specific ratio, and having a long chain branch of a specific value or more in the component However, the present inventors have found that the surface smoothness during extrusion molding is good and that the balance between rigidity and long-term creep properties is excellent, and the present invention has been completed.

That is, the present invention has a density of 925 to 970 kg / m ³ , a melt flow rate (MFR) of 0.05 to 1 g / 10 minutes, and shows two peaks in molecular weight measurement by gel permeation chromatography (GPC). The ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn) is in the range of 2.0 to 7.0, and the long chain in the fraction having a Mn of 100,000 or more upon molecular weight fractionation. The present invention relates to a polyethylene pipe characterized by comprising an ethylene polymer having 0.15 or more branches per 1000 carbon atoms in the main chain.

The ethylene polymer constituting the polyethylene pipe of the present invention has a density measured according to JIS K7676 in the range of 925 to 970 kg / m ³ , preferably in the range of 930 to 965 kg / m ³ , particularly preferably. Is in the range of 935-960 kg / m ³ . Here, if the density exceeds 970 kg / m ³ , long-term creep properties such as ECSR may be reduced, and if the density is less than 925 kg / m ³ , the rigidity for maintaining the internal pressure of the transport fluid may be insufficient. is there.

  The MFR at 190 ° C. and 2.16 kg load of the ethylene polymer constituting the polyethylene pipe of the present invention is 0.05 to 1 g / 10 minutes, preferably 0.1 to 0.5 g / 10 minutes. If it is less than 0.05 g / 10 min, not only the melt viscosity is too high and the extrusion load is large, but also surface roughness occurs during extrusion molding, and the smoothness of the pipe surface may be impaired. If it exceeds 1 g / 10 minutes, melt dripping or the like may occur during extrusion molding, which may deteriorate molding processability and decrease long-term creep properties.

  The ethylene polymer constituting the polyethylene pipe of the present invention shows two peaks in the molecular weight measurement by GPC. The peak top molecular weight (Mp) is obtained by dividing the molecular weight distribution curve obtained by GPC measurement into two peaks by the method described later, and evaluating the top molecular weight of the high molecular weight side peak and the low molecular weight side peak. The case of 100,000 or more was assumed to have two Mp. When it was less than 100,000, the top molecular weight of the actually measured molecular weight distribution curve was defined as one Mp.

  The molecular weight distribution curve was divided as follows. The standard deviation is 0.30 with respect to LogM of the molecular weight distribution curve in which the weight ratio is plotted against LogM which is the logarithm of molecular weight obtained by GPC measurement, and an arbitrary average value (molecular weight at the peak top position) A composite curve is created by adding together two logarithmic distribution curves having) at an arbitrary ratio. Further, the average value and the ratio are obtained so that the deviation sum of squares of the weight ratio with respect to the same molecular weight (M) value of the actually measured molecular weight distribution curve and the composite curve becomes a minimum value. The minimum value of the deviation sum of squares was set to 0.5% or less with respect to the deviation sum of squares when the ratios of the respective peaks were all zero. When the average value and the ratio giving the minimum value of the deviation sum of squares were obtained, the molecular weight at the peak top of each logarithmic distribution curve obtained by dividing into two lognormal distribution curves was defined as Mp.

  In the molecular weight measurement by GPC, one having a peak is not preferable because not only the load during extrusion molding is large, but also surface roughness occurs and the smoothness of the pipe surface is impaired.

  The ratio of the weight average molecular weight (Mw) to Mn (Mw / Mn) is 2.0 to 7.0, preferably 2.5 to 7.0, more preferably 3.0 to 6.0. When Mw / Mn is less than 2.0, not only is the load during extrusion molding large, but also surface roughness occurs and the smoothness of the pipe surface is impaired. If Mw / Mn exceeds 7.0, the impact resistance of the pipe may be reduced. Mw / Mn can be increased by reducing the amount of organic compound added during synthesis of the organically modified clay (B), lowering the temperature during polymerization, and increasing the amount of olefin other than ethylene.

  The number average molecular weight (Mn) measured by GPC is preferably 15,000 or more, more preferably 15,000 to 100,000, and particularly preferably 15,000 to 50,000. When Mn is 15,000 or more, there is no melt dripping at the time of extrusion molding, and the molding processability is excellent and the strength is improved. Mn can be increased by reducing the amount of hydrogenation during polymerization. Mn can be controlled by the type of ligand of the transition metal compound (A). For example, Mn becomes larger when the ligand of the general formula (6) and further the general formula (8) is used than when the ligand of the general formula (5) alone is used.

  The number of long chain branches of the fraction having Mn of 100,000 or more obtained by molecular weight fractionation is 0.15 or more per 1000 carbons of the main chain. When the number of long-chain branches in the fraction with Mn of 100,000 or more is less than 0.15 per 1000 carbons of the main chain, although depending on the MFR of the polyethylene-based polymer, melt dripping occurs during extrusion molding, and molding processing There is a risk of gender deterioration. The number of long-chain branches in the fraction obtained by molecular weight fractionation with Mn of 100,000 or more is increased by reducing the amount of organic compound added during synthesis of the organically modified clay (B) and increasing the amount of olefin other than ethylene during polymerization. be able to. Control is also possible by the type of ligand of the transition metal compound (A). For example, the Mn obtained by molecular weight fractionation is 100,000 or more when the ligand of the general formula (6) and further the general formula (8) is used rather than using the ligand of the general formula (5) only. The number of long-chain branches in the fraction becomes higher.

  Moreover, it is preferable that the ratio of the fraction whose Mn obtained by molecular weight fractionation is 100,000 or more is less than 40% of the whole polymer. When the ratio of the fraction having Mn of 100,000 or more obtained by molecular weight fractionation is less than 40% of the entire polymer, the extrusion load during extrusion molding is small, and the smoothness of the pipe surface is good.

  Regarding the proportion of fractions with Mn of 100,000 or more obtained by molecular weight fractionation, the amount of organic compound added during the synthesis of organically modified clay (B), the amount of hydrogen added during polymerization, the olefin other than ethylene during polymerization It can be increased by increasing the amount added. Control is also possible by the type of ligand of the transition metal compound (A). For example, the Mn obtained by molecular weight fractionation is 100,000 or more when the ligand of the general formula (6) and further the general formula (8) is used rather than using the ligand of the general formula (5) only. The proportion of the fraction becomes higher.

  As other characteristics of the ethylene polymer constituting the polyethylene pipe of the present invention, the number of long-chain branches in the polymer affects the extrusion characteristics, and the larger the number of long-chain branches, the smaller the extrusion load during extrusion molding. This is preferable because the smoothness of the film becomes good.

  Also, the melt tension affects the pipe formability, and by increasing the melt tension, it becomes possible to prevent deterioration of the moldability such as melt dripping, which is preferable.

  As described above, the ethylene polymer used in the present invention has a specific structure, and has excellent surface smoothness at the time of extrusion molding, and is capable of molding a polyethylene pipe excellent in the balance between rigidity and long-term creep property.

The ethylene polymer constituting the polyethylene pipe of the present invention is
The following general formula (1)
M ¹ Q ¹ aQ ² bQ ³ cQ ⁴ d (1)
(In the formula, M ¹ is a titanium atom, a zirconium atom or a hafnium atom, and Q ¹ , Q ² , Q ³ and Q ⁴ are a cycloalkadienyl group, a substituted cycloalkadienyl group, a chelating ligand, Lewis base, hydrogen atom, halogen atom, hydrocarbon group having 1 to 20 carbon atoms, alkoxy group having 1 to 20 carbon atoms, alkylamino group having 1 to 20 carbon atoms, alkylsilyl group having 1 to 20 carbon atoms, the above One in which oxygen is introduced between carbon-carbon bonds of a hydrocarbon group having 1 to 20 carbon atoms, and a part of the hydrocarbon group having 1 to 20 carbon atoms is substituted with an alkylamino group having 1 to 20 carbon atoms In the hydrocarbon group having 1 to 20 carbon atoms, a part of carbon is substituted with silicon, and these may be the same as or different from each other. Q ¹ , Q ² , Q ³ and Q ⁴ are And may be bonded via another atom or atomic group, and a, b, c and d each represent an integer of 0 to 4.)
The transition metal compound (A) represented by the formula (2) is a clay compound belonging to the smectite group hectorite.

（式中、Ｒ^１〜Ｒ^３は各々独立して炭素数１〜３０の炭化水素基、炭素数１〜３０のアルコキシ基、炭素数１〜３０のアルキルアミノ基、炭素数１〜３０のアルキルシリル基、上記炭素数１〜３０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜３０の炭化水素基の一部を炭素数１〜３０のアルキルアミノ基に置換したもの、上記炭素数１〜３０の炭化水素基の一部の炭素をケイ素に置換したもの、であり、かつＲ^１〜Ｒ^３のうち少なくともひとつが炭素数２１以上であり、Ｍ^２は周期表第１５族の原子であり、［Ａ⁻］はアニオンである。）
で表される有機化合物にて変性した有機変性粘土（Ｂ）及び有機アルミニウム化合物（Ｃ）からなるエチレン系重合体製造用触媒を用いて、エチレン重合を行うことにより製造することができる。

(In the formula, R ^{1 to} R ³ are each independently a hydrocarbon group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkylamino group having 1 to 30 carbon atoms, and an alkyl having 1 to 30 carbon atoms. A silyl group, a hydrocarbon group having 1 to 30 carbon atoms in which oxygen is introduced between carbon bonds, and a part of the hydrocarbon group having 1 to 30 carbon atoms is an alkylamino group having 1 to 30 carbon atoms. In which a part of carbon of the hydrocarbon group having 1 to 30 carbon atoms is substituted with silicon, and at least one of R ^{1 to} R ³ has 21 or more carbon atoms, and M ² Is an atom of Group 15 of the periodic table, and [A ⁻ ] is an anion.)
It can manufacture by carrying out ethylene polymerization using the catalyst for ethylene polymer manufacture which consists of the organic modified clay (B) modified | denatured with the organic compound represented by (A), and the organoaluminum compound (C).

The transition metal compound (A) has the following general formula (1)
M ¹ Q ¹ aQ ² bQ ³ cQ ⁴ d (1)
(In the formula, M ¹ is a titanium atom, a zirconium atom or a hafnium atom, and Q ¹ , Q ² , Q ³ and Q ⁴ are a cycloalkadienyl group, a substituted cycloalkadienyl group, a chelating ligand, Lewis base, hydrogen atom, halogen atom, hydrocarbon group having 1 to 20 carbon atoms, alkoxy group having 1 to 20 carbon atoms, alkylamino group having 1 to 20 carbon atoms, alkylsilyl group having 1 to 20 carbon atoms, the above One in which oxygen is introduced between carbon-carbon bonds of a hydrocarbon group having 1 to 20 carbon atoms, and a part of the hydrocarbon group having 1 to 20 carbon atoms is substituted with an alkylamino group having 1 to 20 carbon atoms In the hydrocarbon group having 1 to 20 carbon atoms, a part of carbon is substituted with silicon, and these may be the same as or different from each other. Q ¹ , Q ² , Q ³ and Q ⁴ are And may be bonded via another atom or atomic group, and a, b, c and d each represent an integer of 0 to 4.)
Preferably, the following general formula (3), general formula (4)

［式中、Ｍ^３はチタン原子、ジルコニウム原子またはハフニウム原子であり、Ｘは各々独立して水素原子、ハロゲン原子、炭素数１〜２０の炭化水素基、炭素数１〜２０のアルコキシ基、炭素数１〜２０のアルキルアミノ基、炭素数１〜２０のアルキルシリル基、上記炭素数１〜２０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜２０の炭化水素基の一部を炭素数１〜２０のアルキルアミノ基に置換したもの、上記炭素数１〜２０の炭化水素基の一部の炭素をケイ素に置換したものであり、Ｒ^４，Ｒ^５は各々独立して一般式（５）、（６）、（７）または（８）

[Wherein, M ³ is a titanium atom, a zirconium atom or a hafnium atom, and X is independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, carbon An alkylamino group having 1 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, a hydrocarbon group having 1 to 20 carbon atoms in which oxygen is introduced between carbon-carbon bonds, and the above 1 to 20 carbon atoms A part of the hydrocarbon group is substituted with an alkylamino group having 1 to 20 carbon atoms, a part of the hydrocarbon group having 1 to 20 carbon atoms is substituted with silicon, and R ⁴ , R ⁵ Are each independently the general formula (5), (6), (7) or (8)

（式中、Ｒ^７は各々独立して水素原子、ハロゲン原子、炭素数１〜２０の炭化水素基、炭素数１〜２０のアルキルアミノ基、炭素数１〜２０のアルキルシリル基、上記炭素数１〜２０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜２０の炭化水素基の一部を炭素数１〜２０のアルキルアミノ基に置換したもの、上記炭素数１〜２０の炭化水素基の一部の炭素をケイ素に置換したものである。）
で表されるＭ^３に配位する配位子であり、Ｒ^４とＲ^５はＭ^３と一緒にサンドイッチ構造を形成し、Ｒ^６は一般式（９）または（１０）

(In the formula, each R ⁷ independently represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, an alkylsilyl group having 1 to 20 carbon atoms, or the above carbon number. What introduced oxygen between the carbon-carbon bond of 1-20 hydrocarbon group, What substituted a part of said C1-C20 hydrocarbon group by C1-C20 alkylamino group, The above (Some carbons of the hydrocarbon group having 1 to 20 carbon atoms are substituted with silicon.)
In a ligand coordinating to ^{M 3} represented, a sandwich structure is formed with ^{R 4} and ^{R 5 M 3, R 6} is the formula (9) or (10)

（式中、Ｒ^８は各々独立して水素原子、ハロゲン原子、炭素数１〜２０の炭化水素基、炭素数１〜２０のアルコキシ基、炭素数１〜２０のアルキルアミノ基、炭素数１〜２０のアルキルシリル基、上記炭素数１〜２０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜２０の炭化水素基の一部を炭素数１〜２０のアルキルアミノ基に置換したもの、上記炭素数１〜２０の炭化水素基の一部の炭素をケイ素に置換したものであり、Ｍ^４はケイ素原子、ゲルマニウム原子または錫原子である。）
で表され、Ｒ^４とＲ^５を架橋するように作用しており、ｎは１〜５の整数である。］
で表される化合物が用いられる。

(In the formula, each R ⁸ independently represents a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylamino group having 1 to 20 carbon atoms, or 1 to 1 carbon atoms. 20 alkylsilyl groups, those having oxygen introduced between the carbon-carbon bonds of the hydrocarbon group having 1 to 20 carbon atoms, and some of the hydrocarbon groups having 1 to 20 carbon atoms having 1 to 20 carbon atoms (Substituted by an alkylamino group, or by substituting part of carbon of the hydrocarbon group having 1 to 20 carbon atoms with silicon, and M ⁴ is a silicon atom, a germanium atom, or a tin atom.)
And R ⁴ and R ⁵ are cross-linked and n is an integer of 1 to 5. ]
The compound represented by these is used.

  Further, the following general formula (12) or general formula (13)

［式中、Ｍ^５は、周期表第４〜５族の遷移金属原子を示し、ｍは、１〜２の整数を示し、Ｒ^１１〜Ｒ^１６は、互いに同一でも異なっていてもよく、水素原子、ハロゲン原子、炭素数１〜２０の炭化水素基、炭素数１〜２０のアルキルアミノ基、炭素数１〜２０のアルキルシリル基、上記炭素数１〜２０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜２０の炭化水素基の一部を炭素数１〜２０のアルキルアミノ基に置換したもの、上記炭素数１〜２０の炭化水素基の一部の炭素をケイ素に置換したものであり、Ｒ^１１〜Ｒ^１６のうちの２個以上の基、好ましくは隣接する基が互いに連結して脂肪環、芳香環または、窒素原子などの異原子を含む炭化水素環を形成していてもよく、これらの環はさらに置換基を有していてもよい。ｐは、Ｍ^５の価数を満たす数であり、Ｙは、水素原子、ハロゲン原子、炭素数１〜２０の炭化水素基、炭素数１〜２０のアルコキシ基、炭素数１〜２０のアルキルアミノ基、炭素数１〜２０のアルキルシリル基、上記炭素数１〜２０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜２０の炭化水素基の一部を炭素数１〜２０のアルキルアミノ基に置換したもの、上記炭素数１〜２０の炭化水素基の一部の炭素をケイ素に置換したものを示し、ｐが２以上の場合は、Ｙで示される複数の基は互いに同一でも異なっていてもよく、またＹで示される複数の基は互いに結合して環を形成してもよい。］

[Wherein, M ⁵ represents a transition metal atom of Groups 4 to ⁵ of the periodic table, m represents an integer of 1 to 2, R ^{11 to} R ¹⁶ may be the same as or different from each other, hydrogen Atoms and halogen atoms, hydrocarbon groups having 1 to 20 carbon atoms, alkylamino groups having 1 to 20 carbon atoms, alkylsilyl groups having 1 to 20 carbon atoms, and carbons and carbons of the above hydrocarbon groups having 1 to 20 carbon atoms. One in which oxygen is introduced between the bonds, one in which part of the hydrocarbon group having 1 to 20 carbon atoms is substituted with an alkylamino group having 1 to 20 carbon atoms, part of the hydrocarbon group having 1 to 20 carbon atoms In which two or more groups of R ^{11 to} R ¹⁶ , preferably adjacent groups, are connected to each other to contain an alicyclic ring, an aromatic ring, or a hetero atom such as a nitrogen atom. Hydrocarbon rings may be formed, and these rings further have a substituent. You may do it. p is a number that satisfies the valence of M ⁵ , and Y is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkylamino group having 1 to 20 carbon atoms. A group, an alkylsilyl group having 1 to 20 carbon atoms, a hydrocarbon group having 1 to 20 carbon atoms introduced with oxygen between carbon-carbon bonds, and a part of the hydrocarbon group having 1 to 20 carbon atoms. The one substituted with an alkylamino group having 1 to 20 carbon atoms, the one obtained by substituting a part of carbons of the hydrocarbon group having 1 to 20 carbon atoms with silicon, and when p is 2 or more, it is represented by Y. A plurality of groups may be the same as or different from each other, and a plurality of groups represented by Y may be bonded to each other to form a ring. ]

［式中、Ｒ^１７は各々の場合に水素、ヒドロカルビル、シリル、ゲルミル、ハロ、シアノおよびこれらの組み合わせから独立して選択され、かつ任意に２個のＲ^１７（ここでＲ^１７は水素、ハロまたはシアノではない）は一緒になってシクロペンタジエニル環の隣接位置に連結して結合環構造を形成するその２価誘導体を形成してもよく、Ｊは、Ｍ^６とΠ−錯体を形成する３０個以下の非水素原子を有する中性のη^４−結合ジエン基であり、Ｑは−Ｏ−、−Ｓ−、−ＮＲ^１８−、−ＰＲ^１８−であり、Ｍ^６は＋２形式酸化状態のチタンまたはジルコニウムであり、ＺはＳｉＲ^１８ _２、ＣＲ^１８ _２、ＳｉＲ^１８ _２ＳｉＲ^１８ _２、ＣＲ^１８ _２ＣＲ^１８ _２、ＣＲ^１８＝ＣＲ^１８、ＣＲ^１８ _２ＳｉＲ^１８ _２またはＧｅＲ^１８ _２であり、ここでＲ^１８は各々の場合独立して水素あるいはヒドロカルビル、シリル、ハロゲン化アルキル、ハロゲン化アリールおよびこれらの組み合わせから選択される一員であり、かつ任意にＺからの２個のＲ^１８あるいはＺからのＲ^１８およびＱからのＲ^１８（ここでＲ^１８は水素ではない）が環系を形成してもよい］
で表される化合物を用いることもできる。

[Wherein R ¹⁷ is independently selected in each case from hydrogen, hydrocarbyl, silyl, germyl, halo, cyano and combinations thereof, and optionally two R ^17, where R ¹⁷ is hydrogen, halo Or not cyano) may be joined together to form a divalent derivative thereof linked to the adjacent position of the cyclopentadienyl ring to form a bonded ring structure, and J forms a 錯 体 -complex with M ⁶ A neutral η ⁴ -bonded diene group having 30 or less non-hydrogen atoms, Q is —O—, —S—, —NR ¹⁸ —, —PR ¹⁸ —, and M ⁶ is a +2 formal oxidation a state of titanium or zirconium, Z is _{^{SiR 18 2, CR 18 2,}} SiR 18 2 SiR 18 2, CR 18 2 CR 18 2, CR 18 = CR 18, CR 18 2 SiR 18 2 or GeR ¹ _2, wherein R ¹⁸ is a member selected in each case independently hydrogen or a hydrocarbyl, silyl, halogenated alkyl, halogenated aryl, and combinations thereof, and two R from optionally Z ¹⁸ or ^{R 18} from ^{R 18} and Q from Z (wherein ^{R 18} is not hydrogen) may form a ring system '
The compound represented by these can also be used.

Examples of the cycloalkadienyl group of Q ¹ , Q ² , Q ³ and Q ⁴ include a cyclopentadienyl group, an indenyl group, a fluorenyl group and the like. Examples of substituted cycloalkadienyl groups include 2-methylcyclopentadienyl group, 2-ethylcyclopentadienyl group, 2,4-dimethylcyclopentadienyl group, 2-phenylindenyl group, 2,4-diethylcyclo Pentadienyl group, 2-methoxycyclopentadienyl group, 2-dimethylaminocyclopentadienyl group, 2-trimethylsilylcyclopentadienyl group, 7-methylindenyl group, 7-ethylindenyl group, 7-phenyl Indenyl group, 2,7-dimethylindenyl group, 2-methoxy-7-methylindenyl group, 2-dimethylamino-7-methylindenyl group, 2-trimethylsilyl-7-methylindenyl group, 4,7 -Dimethylindenyl group, 4-methoxy-7-methylindenyl group, tetrahydroindenyl group, 7-methyl Trahydroindenyl group, 7-ethyltetrahydroindenyl group, 7-phenyltetrahydroindenyl group, 2,7-dimethyltetrahydroindenyl group, 2-dimethylamino-7-methyltetrahydroindenyl group, 2-trimethylsilyl-7 -A tetrahydroindenyl group, 4,5,6,7-tetramethyltetrahydroindenyl group, etc. can be illustrated. Examples of the chelating ligand include an ethylenediamine group, a bipyridine group, a phenanthroline group, and an acetylacetonate group. Examples of Lewis bases include amines such as N, N-dimethylaniline, trimethylamine, triethylamine, tri-n-butylamine, methyldiphenylamine and pyridine, phosphines such as triethylphosphine and triphenylphosphine, thioethers such as tetrahydrothiophene, and benzoic acid. Examples include esters such as ethyl acid, and nitriles such as acetonitrile and benzonitrile. Examples of the halogen atom include fluorine, chlorine, bromine, and iodine. Examples of the hydrocarbon group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, n-butyl group, t-butyl group, and n-octyl group. Examples include a group, n-eicosyl group, phenyl group, benzyl group, o-toluyl group, m-toluyl group, p-toluyl group and the like. Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, iso-butoxy group, t-butoxy group, n-octoxy group and n-eoxy group. N-phenoxy group, 2-methylphenoxy group, 3-ethylphenoxy group, and the like. Examples of the alkylamino group having 1 to 20 carbon atoms include a methylamino group, a dimethylamino group, an ethylamino group, a methylethylamino group, and an n-propylamino group. Examples of the alkylsilyl group having 1 to 20 carbon atoms include methylsilyl group, dimethylsilyl group, trimethylsilyl group, ethylsilyl group, diethylsilyl group, triethylsilyl group, n-propylsilyl group, iso-propylsilyl group, and di (n-propylsilyl group). Group), di (iso-propylsilyl group), tri (n-propylsilyl group), tri (iso-propylsilyl group), n-butylsilyl group, iso-butylsilyl group, t-butylsilyl group, di (n-butylsilyl group) Group) and the like. As what introduce | transduced oxygen between carbon of carbon of the said C1-C20 hydrocarbon group, a methoxymethylene group, an ethoxymethylene group, etc. can be illustrated. As what substituted a part of said C1-C20 hydrocarbon group by the C1-C20 alkylamino group, a dimethylaminomethylene group, a diethylaminomethylene group, etc. can be illustrated. As what substituted a part of carbon of the said C1-C20 hydrocarbon group with silicon, a trimethylsilylmethylene group, a tert- butyldimethylsilylmethylene group, etc. can be illustrated.

  Specific examples of the transition metal compound (A) include the following compounds. As specific examples of the transition metal compound (A), those corresponding to the general formula (3) include bis (cyclopentadienyl) zirconium dichloride, bis (methylcyclopentadienyl) zirconium dichloride, bis (butylcyclopentadienyl). ) Zirconium dichloride, those corresponding to general formula (4) include methylene bis (methylcyclopentadienyl) zirconium dichloride, methylene bis (butylcyclopentadienyl) zirconium dichloride, methylene bis (tetramethylcyclopentadienyl) zirconium dichloride, As a thing corresponding to General formula (12), bis (2-tert-butyl-5-phenylimino) zirconium dichloride, as a thing corresponding to General formula (13), (tert-butylamide) ( Zirconium compounds such as tramethyl-η5-cyclopentadienyl) dimethylsilanezirconium dichloride, compounds in which the zirconium atom is changed to titanium atom, hafnium atom, and dichloro form of the above transition metal compounds are dimethyl form, diethyl form, dihydro form, diphenyl form Examples of preferred transition metal compounds (A) include bis (cyclopentadienyl) zirconium dichloride, dimethylsilanediylbis (cyclopentadienyl) zirconium dichloride, and dimethylsilane. Diyl (cyclopentadienyl) (4,7-dimethyl-1-indenyl) zirconium dichloride, dimethylsilanediyl (cyclopentadienyl) (2,4,7-trimethyl-1-indenyl) zirconium di Examples thereof include, but are not limited to, chloride and isopropylidene (cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride.

  The organically modified clay (B) has the following general formula (2)

（式中、Ｒ^１〜Ｒ^３は各々独立して炭素数１〜３０の炭化水素基、炭素数１〜３０のアルコキシ基、炭素数１〜３０のアルキルアミノ基、炭素数１〜３０のアルキルシリル基、上記炭素数１〜３０の炭化水素基の炭素と炭素の結合間に酸素を導入したもの、上記炭素数１〜３０の炭化水素基の一部を炭素数１〜３０のアルキルアミノ基に置換したもの、上記炭素数１〜３０の炭化水素基の一部の炭素をケイ素に置換したものであり、かつＲ^１〜Ｒ^３のうち少なくともひとつが炭素数２１以上であり、Ｍ^２は周期表第１５族の原子であり、［Ａ］はアニオンである。）
で表される有機化合物にて変性したものであり、有機化合物の具体的な例としては、次に例示することができる。

(In the formula, R ^{1 to} R ³ are each independently a hydrocarbon group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkylamino group having 1 to 30 carbon atoms, and an alkyl having 1 to 30 carbon atoms. A silyl group, a hydrocarbon group having 1 to 30 carbon atoms in which oxygen is introduced between carbon bonds, and a part of the hydrocarbon group having 1 to 30 carbon atoms is an alkylamino group having 1 to 30 carbon atoms. In which a part of carbon of the hydrocarbon group having 1 to 30 carbon atoms is substituted with silicon, and at least one of R ^{1 to} R ³ has 21 or more carbon atoms, and M ² is (It is a group 15 atom of the periodic table, and [A] is an anion.)
As a specific example of the organic compound, the following can be exemplified.

In the general formula (2), examples of the hydrocarbon group having 1 to 30 carbon atoms of R ¹ , R ² and R ³ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an allyl group, an n-butyl group, Isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, 2-methylbutyl, 1-methylbutyl, 1-ethylpropyl, neopentyl, tert-pentyl, cyclopentyl, n- A hexyl group etc. can be illustrated.

  Examples of the alkoxy group having 1 to 30 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, an isopropoxy group, and a phenoxy group.

  A C1-C30 alkylamino group is an amino group which has the said C1-C30 hydrocarbon group as a substituent, and is a dimethylamino group, a diethylamino group, a dipropylamino group, a dibutylamino group, a diisopropylamino group. , Diphenylamino group, methylphenylamino group and the like.

  The alkylsilyl group having 1 to 30 carbon atoms is a silyl group having the hydrocarbon group having 1 to 30 carbon atoms as a substituent, and includes a trimethylsilyl group, a tri-tert-butylsilyl group, a ditert-butylmethylsilyl group, a tert- Examples thereof include a butyldimethylsilyl group, a triphenylsilyl group, a diphenylmethylsilyl group, and a phenyldimethylsilyl group.

  As what introduce | transduced oxygen between carbon of carbon of the said C1-C30 hydrocarbon group, a methoxymethylene group, an ethoxymethylene group, etc. can be illustrated.

  As what substituted a part of said C1-C30 hydrocarbon group by the C1-C30 alkylamino group, a dimethylaminomethylene group, a diethylaminomethylene group, etc. can be illustrated.

  As what substituted a part of carbon of the said C1-C30 hydrocarbon group with silicon, a trimethylsilylmethylene group, a tert- butyldimethylsilylmethylene group, etc. can be illustrated.

At least one of R ¹ , R ² and R ³ is a hydrocarbon group having 21 or more carbon atoms represented by a behenyl group.

M ² is an atom of Group 15 of the periodic table, and can be exemplified by a nitrogen atom or a phosphorus atom. Specific examples of the organic compound represented by the general formula (2) when M ² is a nitrogen atom include N, N-dimethyl-behenylamine hydrochloride, N-methyl-N-ethyl-behenylamine hydrochloride, Examples include compounds such as N-methyl-Nn-propyl-behenylamine hydrochloride and the like, and compounds in which the hydrochloride salt of the above compound is replaced with hydrofluoride, hydrobromide, hydroiodide, or sulfate. However, the present invention is not limited to these.

Examples of the compound in which M ² is a phosphorus atom include compounds such as P, P-dimethyl-behenylphosphine hydrochloride, P, P-diethyl-behenylphosphine hydrochloride, P, P-dipropyl-behenylphosphine hydrochloride, Examples thereof include, but are not limited to, compounds in which hydrochloride is replaced with hydrofluoride, hydrobromide, hydroiodide, or sulfate.

[A ⁻ ] is an anion such as fluorine ion, chlorine ion, bromine ion, iodine ion, sulfate ion, nitrate ion, phosphate ion, perchlorate ion, oxalate ion, citrate ion, succinate ion, tetra Although fluoroborate ion or hexafluorophosphate ion can be used, it is not limited to these.

  The clay compound used for the organically modified clay (B) belongs to the smectite group hectorite.

  The organically modified clay modified with an organic compound introduces organic ions between the clay compound layers to form an ionic complex.

  In the organic compound modification treatment, it is preferable to perform the treatment by selecting the conditions of the clay compound concentration of 0.1 to 30% by weight and the treatment temperature of 0 to 150 ° C. Further, the organic compound may be prepared as a solid and dissolved in a solvent for use, or a solution of the organic compound may be prepared by a chemical reaction in the solvent and used as it is. Regarding the reaction amount ratio between the clay compound and the organic compound, it is preferable to use an organic compound having an equivalent amount or more with respect to exchangeable cations of the clay compound. As the treatment solvent, aliphatic hydrocarbons such as pentane, hexane or heptane, aromatic hydrocarbons such as benzene or toluene, alcohols such as ethyl alcohol or methyl alcohol, ethers such as ethyl ether or n-butyl ether, Halogenated hydrocarbons such as methylene chloride or chloroform, acetone, 1,4-dioxane, tetrahydrofuran, water or the like can be used, but preferably alcohols or water is used alone or as a component of a solvent. .

  Further, the particle size of the organically modified clay (B) used for the polymerization of the ethylene polymer used in the present invention is not particularly limited, but if it is too small, it is difficult to settle and the catalyst cannot be prepared efficiently and is too large. When the catalyst is transferred as a slurry, the pipe is clogged in the middle. The method for adjusting the particle size is not particularly limited, and large particles may be pulverized to an appropriate particle size, small particles may be granulated to an appropriate particle size, or pulverization and granulation may be combined. Also good. The particle size may be adjusted for unmodified clay or for modified organically modified clay.

The method of pulverization and granulation is not particularly limited. For pulverization, impact mill, rotary mill, cascade mill, cutter mill, cage mill, impact pulverizer, conical mill, colloid mill, compound mill, jet mill, vibration mill, stamp mill Tube mill, disk mill, tower mill, medium agitator mill, hammer mill, pin mill, fret mill, pebble mill, ball mill, attritor, planetary mill,
Ring ball mill, ring roll mill, rod mill, roller mill, roll crusher, etc., as granulation rolling granulation, fluidized bed granulation, stirring granulation, compression granulation, extrusion granulation, crush granulation, melt granulation, Any method such as spray granulation may be used.

  The organoaluminum compound (C) is a constituent of the catalyst for producing an ethylene polymer used in the present invention, and is used together with the transition metal compound (A) and the organically modified clay (B).

  The organoaluminum compound (C) has the following general formula (11)

（式中、Ｒ^９は炭素数１〜２０の炭化水素基であり、Ｒ^１０は各々独立して炭素数１〜２０の炭化水素基、水素原子または塩素原子である。）
で表され、遷移金属化合物をアルキル化することが可能な化合物が好ましく、具体的にはトリメチルアルミニウム、トリエチルアルミニウム、トリイソブチルアルミニウムなどのアルキルアルミニウムなどを挙げることができる。

(In the formula, R ⁹ is a hydrocarbon group having 1 to 20 carbon atoms, and R ¹⁰ is each independently a hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom, or a chlorine atom.)
And a compound capable of alkylating a transition metal compound is preferable, and specific examples include alkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum.

  Transition metal compound (A) ((A) component) and organically modified clay (B) ((B) component) used in the polymerization of the ethylene polymer used in the present invention, and organoaluminum compound (C) ((C) Although there is no restriction | limiting in the ratio of (component), it is desirable that it is the ratio shown next.

  The molar ratio of the component (A) to the component (C) per metal atom is in the range of (component A) :( component C) = 100: 1 to 1: 100000, particularly in the range of 1: 1 to 1: 10000. It is preferable that the weight ratio of the component (A) to the component (B) is (component A) :( component B) = 10: 1 to 1: 10000, particularly 3: 1 to 1: 1000. It is preferable. In particular, by combining one type of component (A), component (B) and component (C), it is possible to produce an ethylene polymer in which two peaks are observed in molecular weight measurement by GPC. Also, by combining one kind of component (A), component (B) and component (C), in addition to the appearance of the above two peaks, it has a number average molecular weight and molecular weight distribution in a specific range, and is obtained by molecular weight fractionation. The component having a Mn of 100,000 or more is a specific ratio, and the Mn obtained by molecular weight fractionation has a long chain branch of a specific value or more in the component having a Mn of 100,000 or more, so that the surface smoothness at the time of extrusion molding The ethylene-based polymer of the present invention can be obtained which is capable of forming a polyethylene pipe which is good and has a good balance between rigidity and long-term creep property.

  There is no restriction on the method for preparing the ethylene polymer production catalyst comprising the component (A), the component (B) and the component (C) used in the polymerization of the ethylene polymer used in the present invention. Examples of the method include mixing in an inert solvent with respect to each component or using a monomer for polymerization as a solvent. Moreover, there is no restriction | limiting also about the order which makes these components react, and the temperature and processing time which perform this process also have no restriction | limiting. Moreover, it is also possible to prepare an ethylene polymer production catalyst by using two or more kinds of the component (B) and the component (C).

  The catalyst used in the polymerization of the ethylene polymer used in the present invention can be used in any of usual polymerization processes, that is, slurry polymerization, gas phase polymerization, high pressure polymerization, solution polymerization, and bulk polymerization.

In the present invention, polymerization means not only homopolymerization of ethylene but also copolymerization with other olefins, and ethylene polymers obtained by these polymerizations are used to include not only homopolymers but also copolymers. .
The ethylene polymerization in the ethylene polymer used in the present invention can be carried out either in the gas phase or in the liquid phase. In particular, when the polymerization is carried out in the gas phase, the ethylene polymer having a uniform particle shape is efficiently used. It can be produced stably. Further, when the polymerization is performed in a liquid phase, the solvent used may be any organic solvent that is generally used, and specific examples include benzene, toluene, xylene, pentane, hexane, heptane, and the like. Olefins such as 1-butene, 1-octene and 1-hexene can also be used as a solvent.

  Other olefins used for copolymerization of ethylene polymers used in the polymerization of ethylene polymers used in the present invention with propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-hexene, Α-olefins such as octene, styrene and styrene derivatives, butadiene, 1,4-hexadiene, 5-ethylidene-2-norbornene, dicyclopentadiene, 4-methyl-1,4-hexadiene, 7-methyl-1,6- Examples thereof include conjugated and non-conjugated dienes such as octadiene, and cyclic olefins such as cyclobutene. Further, three or more kinds of components can be mixed and polymerized, such as ethylene, propylene and styrene, ethylene, 1-hexene and styrene, ethylene, propylene, and ethylidene norbornene.

In producing the ethylene polymer used in the present invention, there are no particular restrictions on the polymerization conditions such as polymerization temperature, polymerization time, polymerization pressure, monomer concentration, etc., but the polymerization temperature is −100 to 300 ° C., and the polymerization time is The polymerization pressure is preferably in the range of normal pressure to 3000 kg / cm ² G for 10 seconds to 20 hours. It is also possible to adjust the molecular weight using hydrogen during polymerization. The polymerization can be carried out by any of batch, semi-continuous and continuous methods, and can be carried out in two or more stages by changing the polymerization conditions. The ethylene polymer obtained after the completion of the polymerization can be obtained by separating and recovering from the polymerization solvent by a conventionally known method and drying.

  The ethylene polymer constituting the polyethylene pipe of the present invention is not added or, if necessary, an antioxidant, weathering stabilizer, antistatic agent, lubricant, antiblocking agent, organic / inorganic pigment, etc. Additives used may be added. The method of mixing the above-mentioned additives into the resin is not particularly limited, but for example, a method of directly adding in the pellet granulation step after polymerization, or a high concentration master batch is prepared in advance, Examples thereof include a method of dry blending at the time of molding.

  The ethylene polymer constituting the polyethylene pipe of the present invention is a high-density polyethylene, high-pressure low-density polyethylene, ethylene-propylene copolymer rubber, poly-1-butene, etc., within the range not impairing the effects of the present invention. It can also be used by mixing with other thermoplastic resins.

  The method for producing the polyethylene pipe of the present invention is not particularly limited. For example, the above-mentioned polyethylene polymer is melted at a temperature of 170 ° C. to 220 ° C., and a spider straight die attached to a single screw extruder. The outer diameter is formed by extruding into a more cylindrical shape and passing through a sizing plate in a sizing tank, passing through a primary cooling water tank set at 20 ° C. to 60 ° C., and further secondary cooling set at 15 ° C. to 25 ° C. It is formed by passing through a water tank and taking it at a constant speed by a take-up machine.

  The polyethylene pipe of the present invention is suitably used as a gas transportation or water supply / drainage pipe.

  The polyethylene pipe of the present invention has good surface smoothness at the time of extrusion molding and excellent balance between rigidity and long-term creep property as compared with conventional polyethylene pipes, and is therefore suitably used for gas transportation pipes and water supply / drainage pipes. The

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

  Below, the measuring method used by the Example and the comparative example is shown.

-Manufacturing and evaluation of ethylene polymers-
Examples of production will be specifically described below, but the present invention is not limited thereto. Unless otherwise noted, the reagents used were commercially available products or those synthesized according to known methods.

  A jet mill (trade name: CO-JET SYSTEM α MARK III, manufactured by Seishin Enterprise Co., Ltd.) was used for pulverization of the organically modified clay, and the particle size after pulverization was measured using a microtrack particle size distribution analyzer (trade name, manufactured by Nikkiso Co., Ltd.). MT3000) was used to measure ethanol as a dispersant.

  Preparation of the ethylene polymer production catalyst, production of the ethylene polymer and solvent purification were all carried out under an inert gas atmosphere. A hexane solution (20 wt%) of triisobutylaluminum manufactured by Tosoh Finechem Co., Ltd. was used.

  Furthermore, various physical properties of the ethylene-based polymer in the examples were measured by the following methods. Weight average molecular weight (Mw), number average molecular weight (Mn), ratio of weight average molecular weight to number average molecular weight (Mw / Mn) and peak top molecular weight (Mp) were measured by GPC. The column temperature was set to 140 ° C. using a GPC device (trade name: HLC-8121 GPC / HT, manufactured by Tosoh Corporation) and a column (trade name: TSKgel GMHhr-H (20) HT, manufactured by Tosoh Corporation). The measurement was performed using 1,2,4-trichlorobenzene as an eluent. A measurement sample was prepared at a concentration of 1.0 mg / ml, and 0.3 ml was injected and measured. The calibration curve of molecular weight was calibrated using a polystyrene sample having a known molecular weight. In addition, Mw and Mn were calculated | required as a value of linear polyethylene conversion.

  The density was measured by a density gradient tube method in accordance with JIS K6760 (1995).

  MFR (melt flow rate) was measured by a method according to ASTM D1238 Condition E.

The melting point is 200 ° C. using DSC (DSC6200, manufactured by SII Nano Technology).
The sample held for 5 minutes was cooled to −20 ° C. and then calculated by measuring the crystal melting peak when the temperature was raised at 10 ° C./min.

  For molecular weight fractionation, a glass bead packed column (diameter: 21 mm, length: 60 cm) is used as the column, the column temperature is set to 130 ° C., and 1 g of sample dissolved in 30 mL of xylene is injected. Next, distillate is removed by using a xylene / 2-ethoxyethanol ratio of 5/5 as a developing solvent. Thereafter, using xylene as a developing solvent, the components remaining in the column are distilled off to obtain a polymer solution. A component having Mn of 100,000 or more was recovered by adding 5-fold amount of methanol to the obtained polymer solution to precipitate the polymer, filtering and drying.

    The number of long-chain branches was determined by 13C-NMR using a JNM-GSX400 nuclear magnetic resonance apparatus manufactured by JEOL Ltd., and the number of branches equal to or greater than the hexyl group. The solvent is benzene-d6 / orthodichlorobenzene (volume ratio 30/70). The number per 1,000 main chain methylene carbons (chemical shift: 30 ppm) was determined from the average value of the peaks of α-carbon (34.6 ppm) and β-carbon (27.3 ppm).

  The sample for melt tension measurement was prepared by adding a heat-resistant stabilizer (Ciba Specialty Chemicals, Irganox 1010TM; 1,500 ppm, Irgafos 168TM; 1,500 ppm) to an internal mixer (Toyo Seiki Seisakusho, The product kneaded for 30 minutes at 190 ° C. and 30 rpm in a nitrogen stream was used.

  To measure the melt tension, a capillary viscometer (Toyo Seiki Seisakusho, trade name Capillograph) with a barrel diameter of 9.55 mm is attached with a die with a length of 8 mm and a diameter of 2.095 mm so that the inflow angle is 90 °. It was measured. The temperature was set to 160 ° C., the piston lowering speed was set to 10 mm / min, the stretch ratio was set to 47, and the load (mN) required for take-up was the melt tension. When the maximum draw ratio was less than 47, the load (mN) required for taking-up at the highest draw ratio that did not break was taken as the melt tension.

-Pipe forming and its evaluation-
Using a 50 mmφ extruder (manufactured by Ipec) equipped with a spider straight die (outer diameter 38 mm, inner diameter 31 mm), the molten resin was extruded into a cylindrical shape at a cylinder temperature of 170 ° C., a sizing plate and cooled at a take-up speed of 1 m / min. A water tank was passed through to form a pipe having an outer diameter of 32 mm and a thickness of 3 mm, and the moldability, surface smoothness (surface roughness), rigidity (tensile yield strength), and long-term creep property (ESCR) were evaluated.

~ Moldability ~
Those that can be molded by the above molding were marked with ◯, and those that could not be molded were marked with ×.

~ Surface smoothness (surface roughness of pipe surface) ~
The surface roughness Ra value (μm) on the inside of the pipe obtained by the above molding was measured using a digital microscope (Ultra Deep Shape Measurement Microscope VK-8550 manufactured by Keyence Corporation).

~ Rigidity (Tensile yield strength) ~
A No. 1 type small test piece [1 (1/2) type] described in Appendix 1 of JIS-K-7113 was punched out from a pipe and measured according to JIS-K-7113. The measurement was carried out with a tensile tester (manufactured by Toyo Seiki Co., Ltd., trade name: Tensilon UTM-2.5T) at a tensile speed of 50 mm / min.

~ Long term creep (ESCR) ~
This was performed according to JIS-K-6922-2. The test solution used was a 10 wt% aqueous solution of Nippon Oil & Fats Co., Ltd., trade name Nonion NS-210.

Production Example 1
(1) Denaturation of clay 300 mL of industrial alcohol (trade name: Echinen F-3 manufactured by Nippon Alcohol Sales Co., Ltd.) and 300 mL of distilled water are placed in a 1 L flask, and 15.0 g of concentrated hydrochloric acid and dimethylbehenylamine (manufactured by Lion Corporation) (Product name) Armin DM22D) 42.4 g (120 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. The mixture was stirred for 1 hour while maintaining the temperature. The slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 122 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then bis (cyclopenta 0.223 g of dienyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was taken out, washed 5 times with 200 mL of hexane, and then 200 ml of hexane was added to obtain a catalyst suspension (solid weight: 9.74 wt%).
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 146 mg (corresponding to a solid content of 14.2 mg) of the catalyst suspension obtained in (2) were added to 65 ° C. After the temperature increase, 17.5 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure was 0.75 MPa (hydrogen concentration in the ethylene / hydrogen mixed gas: 540 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 13.5 g of polymer (activity: 950 g / g catalyst). The polymer had an MFR of 0.60 g / 10 min, a density of 936 kg / m ³ and a melting point of 122 ° C. The number average molecular weight was 15,700, the weight average molecular weight was 103,700, and peaks were observed at the molecular weights of 30,300 and 205,000. The number of long chain branches contained in the polymer is 0.03 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number of fractions was 0.16 per number, and the fraction of Mn of 100,000 or more when molecular weight fractionation was 16.7 wt% of the total polymer. The melt tension was 90 mN. The evaluation results are shown in Table 1.

Production Example 2
(1) Denaturation of clay 300 mL of industrial alcohol (trade name: Echinen F-3, manufactured by Nippon Alcohol Sales Co., Ltd.) and 300 mL of distilled water are placed in a 1 L flask, and 18.8 g of concentrated hydrochloric acid and dimethylbehenylamine (manufactured by Lion Corporation) (Product name) Armin DM22D) 53.0 g (150 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. The mixture was stirred for 1 hour while maintaining the temperature. This slurry was separated by filtration, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 135 g of an organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene bis ( 0.3485 g of cyclopentadienyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was extracted, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 10.7 wt%).
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 75 mg (corresponding to a solid content of 8.0 mg) of the catalyst suspension obtained in (2) were added to 85 ° C. After the temperature increase, ethylene gas was continuously supplied so that the partial pressure was 1.20 MPa. After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 63.2 g of polymer (activity: 7,900 g / g catalyst). This polymer had an MFR of 0.25 g / 10 min, a density of 954 kg / m ³ , and a melting point of 132 ° C. The number average molecular weight was 11,400, the weight average molecular weight was 43,000, and peaks were observed at molecular weights of 18,100 and 189,200. Further, the number of long chain branches contained in the polymer is 0.05 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.17 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 9.2 wt% of the total polymer. The melt tension was 95 mN. The evaluation results are shown in Table 1.

Production Example 3
(1) Denaturation of clay 300 mL of industrial alcohol (trade name: Echinen F-3, manufactured by Japan Alcohol Sales Co., Ltd.) and 300 mL of distilled water are placed in a 1 L flask, and 12.5 g of concentrated hydrochloric acid and dimethylbehenylamine (manufactured by Lion Corporation) (Trade name) Armin DM22D) 35.3 g (100 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. The mixture was stirred for 1 hour while maintaining the temperature. The slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 118 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclohexane) 0.4266 g of pentadienyl) (4,7-dimethyl-1-indenyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was taken out, washed 5 times with 200 mL of hexane, and then 200 ml of hexane was added to obtain a catalyst suspension (solid weight: 12.5 wt%).
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum in a 2 L autoclave, and 105 mg (corresponding to a solid content of 13.1 mg) of the catalyst suspension obtained in (2) were added, and the mixture was heated to 85 ° C. After the temperature increase, ethylene gas was continuously supplied so that the partial pressure became 0.90 MPa. After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 50.2 g of polymer (activity: 3,800 g / g catalyst). This polymer had an MFR of 9.90 g / 10 min, a density of 956 kg / m ³ , and a melting point of 135 ° C. The number average molecular weight was 17,900, the weight average molecular weight was 65,800, and peaks were observed at the molecular weights of 36,500 and 297,000. The number of long chain branches contained in the polymer is 0.10 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.20 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 7.7 wt% of the total polymer. The melt tension was 30 mN. The evaluation results are shown in Table 1.

Production Example 4
(1) Modification of clay The same procedure as in Example 1 was performed.
(2) Preparation of catalyst suspension Instead of bis (cyclopentadienyl) zirconium dichloride / 0.2923 g, dimethylsilylene (cyclopentadienyl) (2,4,7-trimethyl-1-indenyl) zirconium dichloride / The same operation as in Example 1 was performed except that 0.4406 g was used (solid weight: 11.5 wt%).
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum was added to a 2 L autoclave, and 90 mg of the catalyst suspension obtained in (2) (corresponding to a solid content of 10.4 mg) was added to 65 ° C. After the temperature increase, 17.5 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure was 0.75 MPa (hydrogen concentration in the ethylene / hydrogen mixed gas: 550 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 61.4 g of polymer (activity: 5,900 g / g catalyst). This polymer had an MFR of 0.08 g / 10 min, a density of 926 kg / m ³ and a melting point of 113 ° C. The number average molecular weight was 21,900, the weight average molecular weight was 127,000, and peaks were observed at molecular weights of 31,300 and 247,800. Further, the number of long chain branches contained in the polymer is 0.17 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.32 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 36.9 wt% of the total polymer. The melt tension was 140 mN. The evaluation results are shown in Table 1.

Production Example 5
(1) Modification of clay The same procedure as in Example 1 was performed.
(2) Preparation of catalyst suspension Instead of bis (cyclopentadienyl) zirconium dichloride / 0.2923 g, dimethylmethylene (cyclopentadienyl) (2,7-di-t-butyl-9-fluorenyl) zirconium The same procedure as in Example 1 was carried out except that dichloride / 0.5447 g was used (solid weight content: 10.9 wt%).
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum in a 2 L autoclave, and 86 mg of the catalyst suspension obtained in (2) (equivalent to 9.4 mg of solid content) were added to 65 ° C. After the temperature increase, 17.5 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.75 MPa (hydrogen concentration in the ethylene / hydrogen mixed gas: 610 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 17.9 g of polymer (activity: 1,900 g / g catalyst). The polymer had an MFR of 5.00 g / 10 min, a density of 910 kg / m ³ , and melting points of 80 ° C. and 99 ° C. The number average molecular weight was 28,000, the weight average molecular weight was 82,300, and peaks were observed at the positions of molecular weights 42,500 and 260,900. The number of long chain branches contained in the polymer is 0.25 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.40 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 39.8 wt% of the total polymer. The melt tension was 45 mN. The evaluation results are shown in Table 1.

Production Example 6
(1) Modification of clay (2) Preparation of catalyst suspension The same procedure as in Example 4 was performed.
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 64 mg (corresponding to a solid content of 7.3 mg) of the catalyst suspension obtained in (2) were added. After the temperature increase, 17.6 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.80 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 570 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 61.7 g of polymer (activity: 8,500 g / g catalyst). This polymer had an MFR of 1.40 g / 10 min, a density of 929 kg / m ³ , and a melting point of 117 ° C. The number average molecular weight was 19,500, the weight average molecular weight was 92,700, and peaks were observed at molecular weights of 31,200 and 183,200. Further, the number of long chain branches contained in the polymer is 0.16 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.31 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 21.8 wt% of the total polymer. The melt tension was 78 mN. The evaluation results are shown in Table 1.

Production Example 7
(1) Modification of clay Performed in the same manner as in Example 2.
(2) Preparation of catalyst suspension Dimethylsilylene (cyclopentadienyl) (2,4,7-trimethyl-1-indenyl) zirconium instead of dimethylsilylene bis (cyclopentadienyl) zirconium dichloride / 0.3485 g The same operation as in Example 2 was carried out except that dichloride / 0.4406 g was used (solid weight: 11.9 wt%).
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum in a 2 L autoclave, and 54 mg of catalyst suspension obtained in (2) (corresponding to a solid content of 6.4 mg) were added, and the mixture was heated to 70 ° C. After the temperature increase, 17.6 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.80 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 580 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 37.6 g of polymer (activity: 5,900 g / g catalyst). This polymer had an MFR of 0.07 g / 10 min, a density of 925 kg / m ³ , and a melting point of 114 ° C. The number average molecular weight was 26,300, the weight average molecular weight was 146,300, and peaks were observed at the positions of molecular weights 42,800 and 260,800. The number of long chain branches contained in the polymer is 0.20 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.37 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 32.7 wt% of the total polymer. The melt tension was 150 mN. The evaluation results are shown in Table 1.

Production Example 8
(1) Denaturation of clay 300 mL of industrial alcohol (trade name: Echinen F-3, manufactured by Nippon Alcohol Sales Co., Ltd.) and 300 mL of distilled water are placed in a 1 L flask, and 17.5 g of concentrated hydrochloric acid and dimethylbehenylamine (manufactured by Lion Corporation) (Trade name) Armin DM22D) 49.4 g (140 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. The mixture was stirred for 1 hour while maintaining the temperature. The slurry was separated by filtration, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 132 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclohexane) 0.4406 g of pentadienyl) (2,4,7-trimethylindenyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was taken out, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 12.4 wt%).
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 52 mg (corresponding to a solid content of 6.4 mg) of the catalyst suspension obtained in (2) were added. After the temperature increase, 17.6 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.80 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 590 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 61.8 g of polymer (activity: 9,700 g / g catalyst). The MFR of this polymer was 1.60 g / 10 min, the density was 930 kg / m ³ , and the melting point was 118 ° C. The number average molecular weight was 17,600, the weight average molecular weight was 86,700, and peaks were observed at the molecular weights of 30,500 and 155,300. The number of long chain branches contained in the polymer is 0.14 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.27 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 20.1 wt% of the total polymer. The melt tension was 75 mN. The evaluation results are shown in Table 1.

Production Example 9
(1) Denaturation of clay 300 mL of industrial alcohol (trade name: Echinen F-3 manufactured by Nippon Alcohol Sales Co., Ltd.) and 300 mL of distilled water are placed in a 1 L flask, and 20.0 g of concentrated hydrochloric acid and dimethylbehenylamine (manufactured by Lion Corporation) (Product Name) Armin DM22D) 56.5 g (160 mmol) was added, heated to 45 ° C. to disperse 100 g of synthetic hectorite (Rockwood Additives (trade name) Laponite RDS), and then heated to 60 ° C. The mixture was stirred for 1 hour while maintaining the temperature. This slurry was filtered, washed twice with 600 mL of water at 60 ° C., and dried in an oven at 85 ° C. for 12 hours to obtain 145 g of organically modified clay. This organically modified clay was crushed by a jet mill to have a median diameter of 15 μm.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) and 108 mL of hexane were added, and then dimethylsilylene (cyclohexane) 0.4406 g of pentadienyl) (2,4,7-trimethyl-1-indenyl) zirconium dichloride and 142 mL of 20% triisobutylaluminum were added and stirred at 60 ° C. for 3 hours. After cooling to 45 ° C., the supernatant was extracted, washed 5 times with 200 mL of hexane, and then 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 11.2 wt%).
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 74 mg (corresponding to a solid content of 8.3 mg) of the catalyst suspension obtained in (2) were added to 65 ° C. After the temperature increase, 17.5 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure was 0.75 MPa (hydrogen concentration in the ethylene / hydrogen mixed gas: 570 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 51.5 g of polymer (activity: 6,200 g / g catalyst). The polymer had an MFR of 0.80 g / 10 min, a density of 928 kg / m ³ , and a melting point of 115 ° C. The number average molecular weight was 17,900, the weight average molecular weight was 99,300, and peaks were observed at molecular weights of 28,100 and 229,100. The number of long chain branches contained in the polymer is 0.14 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.26 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 25.4 wt% of the total polymer. The melt tension was 90 mN. The evaluation results are shown in Table 1.

Production Example 10
(1) Modification of clay (2) Preparation of catalyst suspension The same procedure as in Production Example 4 was performed.
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum was added to a 2 L autoclave, and 125 mg (corresponding to a solid content of 15.0 mg) of the catalyst suspension obtained in (2) was added at 65 ° C. After raising the temperature to 17.5 g of 1-butene, the ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure was 0.75 MPa (the concentration of hydrogen in the ethylene / hydrogen mixed gas: 1,000 ppm). ). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 75.0 g of polymer (activity: 5,000 g / g catalyst). This polymer had an MFR of 1.00 g / 10 min, a density of 920 kg / m ³ , and a melting point of 108 ° C. The number average molecular weight was 20,700, the weight average molecular weight was 105,700, and peaks were observed at molecular weights of 32,400 and 250,300. Further, the number of long chain branches contained in the polymer is 0.19 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.34 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 24.6 wt% of the total polymer. The melt tension was 81 mN. The evaluation results are shown in Table 1.

Production Example 11
(1) Modification of clay (2) Preparation of catalyst suspension The same procedure as in Production Example 4 was performed.
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 58 mg (corresponding to a solid content of 7.0 mg) of the catalyst suspension obtained in (2) were added. After the temperature rise, 8.3 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.85 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 850 ppm). After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 49.0 g of polymer (activity: 7,000 g / g catalyst). This polymer had an MFR of 3.70 g / 10 min, a density of 939 kg / m ³ and a melting point of 125 ° C. The number average molecular weight was 20,300, the weight average molecular weight was 75,200, and peaks were observed at the positions of molecular weights of 40,700 and 216,200. The number of long chain branches contained in the polymer is 0.06 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.17 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 14.3 wt% of the total polymer. The melt tension was 50 mN. The evaluation results are shown in Table 1.

Production Example 12
(1) Modification of clay (2) Preparation of catalyst suspension The same procedure as in Production Example 4 was performed.
(3) Polymerization 1.2 L of hexane, 1.0 mL of 20% triisobutylaluminum in a 2 L autoclave, and 60 mg of the catalyst suspension obtained in (2) (equivalent to a solid content of 7.2 mg) were added to 80 ° C. After the temperature increase, 8.3 g of 1-butene was added, and an ethylene / hydrogen mixed gas was continuously supplied so that the partial pressure became 0.85 MPa (concentration of hydrogen in the ethylene / hydrogen mixed gas: 350 ppm). After 90 minutes, the pressure was released, and the slurry was filtered off and dried to obtain 54.0 g of polymer (activity: 7,500 g / g catalyst). The polymer had an MFR of 0.35 g / 10 min, a density of 935 kg / m ³ and a melting point of 125 ° C. The number average molecular weight was 35,500, the weight average molecular weight was 124,300, and peaks were observed at the molecular weights 71,200 and 338,100. The number of long chain branches contained in the polymer is 0.10 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.20 per number. Moreover, the ratio of the fraction of Mn 100,000 or more when molecular weight fractionation was 17.0 wt% of the total polymer. The melt tension was 95 mN. The evaluation results are shown in Table 1.

Production Example 13
(1) Modification of clay The same procedure as in Production Example 1 was performed.
(2) Preparation of catalyst suspension After substituting a 300 mL flask equipped with a thermometer and a reflux tube with nitrogen, 25.0 g of the organically modified clay obtained in (1) was suspended in 165 mL of hexane, and dimethylsilanediyl Bis (cyclopentadienyl) zirconium dichloride (0.3485 g) and triethylaluminum in hexane (1.18 M) (85 mL) were added, and the mixture was stirred at 60 ° C. for 3 hours. After allowing to stand and cooling to room temperature, the supernatant was taken out and washed twice with 200 mL of a 1% triisobutylaluminum hexane solution. The supernatant liquid after washing was extracted and the whole was made up to 250 mL with a 5% triisobutylaluminum hexane solution. Subsequently, a 20% triisobutylaluminum hexane solution (0%) was added to a suspension of diphenylmethylene (1-cyclopentadienyl) (2,7-di-tert-butyl-9-fluorenyl) zirconium dichloride 0.1165 g in hexane 10 mL. .71M) The solution prepared by adding 5 ml was added and stirred at room temperature for 6 hours. The supernatant was removed by standing, and after washing twice with 200 mL of hexane, 200 mL of hexane was added to obtain a catalyst suspension (solid weight: 12.0 wt%).
(3) Polymerization 1.2 L of hexane and 1.0 mL of 20% triisobutylaluminum were added to a 2 L autoclave, and 125 mg (corresponding to a solid content of 15.0 mg) of the catalyst suspension obtained in (2) were added to 85 ° C. After the temperature increase, 2.4 g of 1-butene was added, and ethylene was continuously supplied so that the partial pressure became 0.90 MPa. After 90 minutes, the pressure was released, and the slurry was filtered and dried to obtain 45.0 g of polymer (activity: 3,000 g / g catalyst). The polymer had an MFR of 4.40 g / 10 min, a density of 951 kg / m ³ and a melting point of 128 ° C. The number average molecular weight was 9,100, the weight average molecular weight was 77,100, and peaks were observed at molecular weights of 10,400 and 168,400. Further, the number of long chain branches contained in the polymer is 0.11 per 1000 carbons of the main chain, and the number of long chain branches contained in the fraction of Mn of 100,000 or more when molecular weight fractionation is 1000 carbons of the main chain. The number was 0.24 per number. Moreover, the ratio of the fraction of Mn of 100,000 or more when molecular weight fractionation was 15.7 wt% of the total polymer. The melt tension was 210 mN. The evaluation results are shown in Table 1.

Example 1
The ethylene polymer obtained in Production Example 1 was molded into a pipe having an outer diameter of 32 mm and a thickness of 3 mm using a pipe molding machine (manufactured by Ipec Co., Ltd.) having a 50 mmφ extrusion screw. Roughness), rigidity (tensile yield strength), and long term creep properties (ESCR) were evaluated. It was confirmed that the obtained pipe had a smooth surface and an excellent balance between rigidity and long-term creep property. The evaluation results are shown in Table 2.

Examples 2-6
Except having changed the ethylene-type polymer as shown in Table 2, it shape | molded similarly to Example 1 and evaluated. The results are shown in Table 2.

Comparative Examples 1-7
Except having changed the ethylene-type polymer as shown in Table 3, it shape | molded similarly to Example 1 and evaluated. The results are shown in Table 3.

Comparative Example 8
Molded in the same manner as in Example 1 using a commercially available low density polyethylene (Petrocene 173 manufactured by Tosoh Corporation, MFR = 0.30 g / 10 min, density = 924 kg / m ³ ) instead of the ethylene polymer, and evaluation Went. The characteristics of the low density polyethylene are shown in Reference Example 1 of Table 1, and the molding evaluation results are shown in Table 3.

Comparative Example 9
Molded in the same manner as in Example 1 using commercially available high-density polyethylene (RS1000 manufactured by Nippon Polyolefin Co., Ltd., MFR = 0.1 g / 10 min, density = 953 kg / m ³ ) instead of the ethylene polymer, and evaluated. Went. The characteristics of the high density polyethylene are shown in Reference Example 2 of Table 1, and the molding evaluation results are shown in Table 3.

Comparative Example 10
Molded in the same manner as in Example 1 using a commercially available high-density polyethylene (KBX47D manufactured by Nippon Polyethylene Co., Ltd., MFR = 0.04 g / 10 min, density = 946 kg / m ³ ) instead of the ethylene polymer, and evaluated. Went. The characteristics of the high density polyethylene are shown in Reference Example 3 in Table 1, and the molding evaluation results are shown in Table 3.

Claims (2)

The following general formula
[M ¹ Q ¹ aQ ² bQ ³ cQ ⁴ d] (1)
(In the formula, M ¹ is a titanium atom, a zirconium atom or a hafnium atom, and Q ¹ , Q ² , Q ³ and Q ⁴ are a cycloalkadienyl group, a substituted cycloalkadienyl group, a chelating ligand, Lewis base, hydrogen atom, halogen atom, hydrocarbon group having 1 to 20 carbon atoms, alkoxy group having 1 to 20 carbon atoms, alkylamino group having 1 to 20 carbon atoms, alkylsilyl group having 1 to 20 carbon atoms, the above One in which oxygen is introduced between carbon-carbon bonds of a hydrocarbon group having 1 to 20 carbon atoms, and a part of the hydrocarbon group having 1 to 20 carbon atoms is substituted with an alkylamino group having 1 to 20 carbon atoms In the hydrocarbon group having 1 to 20 carbon atoms, a part of carbon is substituted with silicon, and these may be the same as or different from each other. Q ¹ , Q ² , Q ³ and Q ⁴ are And may be bonded via another atom or atomic group, and a, b, c and d each represent an integer of 0 to 4.)
A transition metal compound represented by the formula (A), a clay compound belonging to the smectite hectorite is represented by the general formula

(In the formula, R ^{1 to} R ³ are each independently a hydrocarbon group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkylamino group having 1 to 30 carbon atoms, and an alkyl having 1 to 30 carbon atoms. A silyl group, a hydrocarbon group having 1 to 30 carbon atoms in which oxygen is introduced between carbon bonds, and a part of the hydrocarbon group having 1 to 30 carbon atoms is an alkylamino group having 1 to 30 carbon atoms. In which a part of carbon of the hydrocarbon group having 1 to 30 carbon atoms is substituted with silicon, and at least one of R ^{1 to} R ³ has 21 or more carbon atoms, and M ² Is an atom of Group 15 of the periodic table, and [A ⁻ ] is an anion.) An ethylene-based polymer comprising an organically modified clay (B) and an organoaluminum compound (C) modified with an organic compound represented by To conduct ethylene polymerization using a catalyst for production Ri produced, density 925~970kg / ^{m 3,} a melt flow rate (MFR) 0.05 to 1 g / 10 min, showed two peaks in the molecular weight determination by gel permeation chromatography, the weight-average molecular weight The ratio of (Mw) to number average molecular weight (Mn) (Mw / Mn) is in the range of 2.0 to 7.0, and long chain branching is performed in the fraction having Mn of 100,000 or more when molecular weight fractionation is performed. A polyethylene pipe comprising an ethylene polymer having 0.15 or more per 1000 carbon atoms. The polyethylene pipe according to claim 1, wherein Mw / Mn of the ethylene-based polymer is in a range of 3.0 to 6.0, and Mn is 15,000 or more.