JP4868853B2 - Ultra high molecular weight ethylene polymer - Google Patents

Description

  The present invention relates to an ultra high molecular weight ethylene polymer (ethylene homopolymer or ethylene copolymer) having an ultra high molecular weight of 1 million or more, a molecular weight distribution larger than 3, and a small amount of residual Ti and residual Cl in the polymer. And a method for producing such an ultrahigh molecular weight ethylene polymer.

Conventionally, ultra-high molecular weight olefins, especially ultra-high molecular weight polyethylene, are superior in impact resistance, wear resistance, slidability, and chemical resistance compared to general-purpose polyethylene, and can be used as sliding parts. It is positioned as a kind of plastic. Moreover, after uniformly mixing with a plasticizer such as paraffin oil, it is extruded into a sheet, film, or fiber, and in some cases, stretched to provide a separator for lithium ion batteries and a separator for lead acid batteries, It is also used for strength and highly elastic fibers.
Ultra high molecular weight polyethylene obtained with a metallocene catalyst has a narrow molecular weight distribution (Mw / Mn) of 3 or less and can be expected to improve impact resistance. However, since it has few low molecular weight components, It is difficult to melt and the part that has not been melted is not completely fused, resulting in a non-uniform shaped body. This is a weak physical property, and there is a problem that the performance cannot be fully exhibited even though it is originally a material having high impact resistance. Even plasticizers are difficult to dissolve uniformly and remain as an undissolved product, which tends to adversely affect the strength and film properties of the product. Moreover, when the entanglement between molecules becomes strong and stretching is necessary like a fiber, there is a problem that it is difficult to obtain necessary stretchability.
On the other hand, ultra-high molecular weight polyethylene obtained with a Ziegler-Natta catalyst generally has a broad molecular weight distribution and contains many low molecular weight components. Excellent performance in terms of stretchability and the like. However, the ultra-high molecular weight polyethylene obtained with the Ziegler-Natta catalyst has a large amount of remaining Ti and Cl, and thermal degradation is likely to occur during molding at high temperatures. For this reason, the molecular weight of the ultra-high molecular weight component may be reduced by the molecular chain cleavage, and the physical properties as the original ultra-high molecular weight may not be exhibited.
Ultra high molecular weight polyethylene is also used in ski soles because of its low friction coefficient and good slipperiness. However, ultra high molecular weight polyethylene has high crystallinity and is white and opaque, and is inferior in transparency even if it is in the form of a thin sheet or film, so that the design properties such as the brand name of the ski board sole are impaired. In view of such a current situation, a material having excellent transparency is demanded. In order to improve the transparency, Japanese Patent Publication No. 05-86803 proposes an ultrahigh molecular weight ethylene copolymer obtained from ethylene and another α-olefin (comonomer). However, when ethylene and an α-olefin are copolymerized, it is necessary to lower the polymerization temperature in order to increase the molecular weight, but such a decrease in the polymerization temperature causes a decrease in the efficiency of the industrial process. Conversely, when the copolymerization is carried out at 70 to 100 ° C., which is efficient in an industrial process, the molecular weight of the resulting copolymer is reduced. As a result, there is a problem that the wear resistance, which is a feature of the ultrahigh molecular weight polymer, is lowered and the friction coefficient is also increased. In addition, when a normal Ziegler-Natta catalyst is used in the copolymerization of ethylene and α-olefin, the comonomer α-olefin is uniformly and sufficiently inserted into the molecular chain of the copolymer. In addition, when it was made into a plate shape, sufficient transparency was not obtained.
Japanese Patent Application Laid-Open No. 09-291112 discloses an ultrahigh molecular weight ethylene (co) polymer having a very narrow molecular weight distribution using a metallocene catalyst, but the density and melting point are sufficient even in the case of a copolymer. The transparency was not sufficiently improved. Although it is disclosed in Japanese Patent Application Laid-Open No. 09-309926 that an ethylene copolymer having a relatively wide molecular weight distribution can be obtained using a metallocene-based catalyst, a description of an ultrahigh molecular weight ethylene copolymer having a molecular weight of 1 million or more is disclosed. There is no. Further, an ultrahigh molecular weight ethylene polymer having excellent wear characteristics obtained by using a metallocene catalyst is also described in JP-A-11-106417. However, since the melting point is high even if the molecular weight is high, press molding is performed. It tends to be a non-uniform plate during processing and has poor moldability.
On the other hand, it is known that an ethylene polymer having a high activity, a narrow molecular weight distribution, and a uniform composition distribution of constituent molecules can be obtained by using a metallocene catalyst. However, as a process problem in the polymerization using such a metallocene catalyst, the initial polymerization rate is generally high and a rapid polymerization reaction occurs when the catalyst and ethylene come into contact with each other, so heat removal cannot catch up. In the polymer, local heat generation sites (heat spots) are generated due to heat of polymerization. As a result, a part of the particulate polymer has a melting point or higher, and there is a problem that the polymers are fused together to form a bulk polymer. In the case of a continuous process, when such a bulk polymer is generated, the polymer extraction pipe from the polymerization reactor is blocked, so that the polymer cannot be extracted and the continuous operation is hindered.
In order to solve the above problems, Japanese Patent Application Laid-Open No. 2000-198804 and Japanese Patent Application Laid-Open No. 2001-302716 are characterized in that a metallocene catalyst is previously brought into contact with hydrogen and then introduced into a polymerization reactor. A method for producing an ethylene polymer has been proposed. However, since hydrogen, which is a chain transfer agent, is used, the molecular weight of the obtained ethylene polymer has a limit.

を満足する、上記１項記載の超高分子量エチレン系重合体。
［３］末端ビニル基量が０．０２（個／１０００Ｃ）以下である、上記１又２項に記載の超高分子量エチレン系重合体。
［４］密度ρ（ｇ／ｃｃ）と粘度平均分子量Ｍｖの関係が、下記式（２）：

を満足する、上記１〜３項のいずれか１項に記載の超高分子量エチレン系重合体。
［５］密度ρが０．８５０〜０．９２５ｇ／ｃｃである、上記１〜４項のいずれか１項に記載の超高分子量エチレン系重合体。
［６］ＡＳＴＭ Ｄ１００３に従って測定した透明性の指標であるＨＡＺＥが７０％以下である、上記１〜３及び５項のいずれか１項に記載の超高分子量エチレン系重合体。
［７］ＧＰＣ／ＦＴ−ＩＲで測定したコモノマーの挿入量分布において、重合体の分子量が大きくなるほど該コモノマーの挿入量も多くなっている、上記１〜３及び５〜６項のいずれか１項に記載の超高分子量エチレン系重合体。
［８］分子量分布プロファイルが、ＧＰＣ／ＦＴ−ＩＲ測定により下記式（３）：

（式中、Ｍｔは分子量分布プロファイル上の分子量で表される１地点であって、上記プロファイルが最大強度のピークを示す地点であり、Ｍｃは上記分子量分布プロファイル上の分子量で表される任意点である。）
で定義される範囲内である場合において、
コモノマー濃度プロファイルの最小二乗法による近似直線の傾きが、下記式（４）：

（式中、Ｍｃ^１およびＭｃ^２は、式（３）を満足させる分子量で表される２つの異なる任意点Ｍｃであり、Ｃ（Ｍｃ^１）およびＣ（Ｍｃ^２）は、それぞれ上記近似直線上のＭｃ^１およびＭｃ^２に相当するコモノマー濃度である。）
で定義される範囲を満たす、上記７項記載の超高分子量エチレン系重合体。
［９］ＣＦＣの測定において、最大抽出量を示す温度よりも１０℃以上低い温度で抽出される重合体画分の合計量が全体抽出量を基準にして８重量％以下である、上記１〜３及び５〜８項のいずれか１項に記載の超高分子量エチレン系重合体。
［１０］ＣＦＣの測定において、最大抽出量を示す第一温度と第一温度より１０℃高い第二温度の間の範囲内にある任意温度Ｔ（℃）での抽出において、
任意温度Ｔ（℃）と、任意温度Ｔ（℃）で抽出される重合体画分が示す分子量分布プロファイル上の分子量で表される１地点であって、最大強度のピークを示す分子量で表される地点Ｍｐ（Ｔ）との間の関係を最小二乗法で処理して近似直線を得るとき、この近似直線が下記式（５）：

（式中、Ｔ^１およびＴ^２は、上記第一温度と上記第二温度の間の範囲内にある２つの異なる任意抽出温度Ｔ（℃）であり、Ｍｐ（Ｔ^１）およびＭｐ（Ｔ^２）は、それぞれ上記近似直線上のＴ^１およびＴ^２に相当する分子量である。）
を満足し、かつ
ＣＦＣで測定したとき、上記第一温度より１０℃以上低い温度で抽出される重合体画分の合計量が、ＣＦＣ測定における全範囲の温度で抽出される重合体画分の全量を基準にして８重量％以下である、上記９項記載の超高分子量エチレン系重合体。
［１１］上記１〜１０項のいずれか１項に記載の超高分子量エチレン系重合体の製造方法であって、１種以上のオレフィンを重合するに際し、予め水素化剤と接触させたメタロセン系触媒（Ｃ）と水素添加能を有する化合物（Ｄ）を用いる、上記方法。
［１２］水素化剤が、水素及び／又は少なくとも一種のＲ_ｎＳｉＨ_４−ｎ（式中、０≦ｎ≦１、Ｒは炭素原子数１〜４のアルキル基、炭素原子数６〜１２のアリール基、炭素原子数７〜２０のアルキルアリール基、炭素原子数７〜２０のアリールアルキル基、炭素原子数２〜２０のアルケニル基からなる群より選ばれる炭化水素基である。）である、上記１１項記載の方法。
［１３］メタロセン系触媒（Ｃ）が、下記式（６）：

（式中、Ｌは、各々独立して、シクロペンタジエニル基、インデニル基、テトラヒドロインデニル基、フルオレニル基、テトラヒドロフルオレニル基、及びオクタヒドロフルオレニル基からなる群より選ばれる環状η結合性アニオン配位子を表し、該配位子は場合によっては１〜８個の置換基を有し、該置換基は各々独立して炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基であり、
Ｍは、形式酸化数が＋２、＋３または＋４の周期表第４族に属する遷移金属群から選ばれる遷移金属であって、少なくとも１つの配位子Ｌにη^５結合している遷移金属を表し、
Ｗは、１〜５０個の非水素原子を有する２価の置換基であって、ＬとＭとに各々１価ずつの価数で結合し、これによりＬ及びＭと共働してメタラサイクルを形成する２価の置換基を表し、
Ｘは、各々独立して、１価のアニオン性σ結合型配位子、Ｍと２価で結合する２価のアニオン性σ結合型配位子、及びＬとＭとに各々１価ずつの価数で結合する２価のアニオン性σ結合型配位子からなる群より選ばれる、１〜６０個の非水素原子を有するアニオン性σ結合型配位子を表し、
Ｘ’は、各々独立して、１〜４０個の非水素原子を有する中性ルイス塩基配位性化合物を表し、
ｊは１または２であり、但し、ｊが２である時、場合によっては２つの配位子Ｌが、１〜２０個の非水素原子を有する２価の基を介して互いに結合し、該２価の基は炭素数１〜２０のヒドロカルバジイル基、炭素数１〜１２のハロヒドロカルバジイル基、炭素数１〜１２のヒドロカルビレンオキシ基、炭素数１〜１２のヒドロカルビレンアミノ基、シランジイル基、ハロシランジイル基、及びシリレンアミノ基からなる群より選ばれる基であり、
ｋは０または１であり、
ｐは０、１または２であり、但し、Ｘが１価のアニオン性σ結合型配位子、またはＬとＭとに結合している２価のアニオン性σ結合型配位子である場合、ｐはＭの形式酸化数より１以上小さい整数であり、またＸがＭにのみ結合している２価のアニオン性σ結合型配位子である場合、ｐはＭの形式酸化数より（ｊ＋１）以上小さい整数であり、
ｑは０、１または２である。）
で表される少なくとも１種の化合物を用いて形成されたものである、上記１１項記載の方法。
［１４］メタロセン系触媒（Ｃ）が、下記式（７）：

（式中、［Ｌ−Ｈ］^ｄ＋はプロトン供与性のブレンステッド酸を表し、但し、Ｌは中性のルイス塩基を表し、ｄは１〜７の整数であり；［Ｍ_ｍＱ_ｐ］^ｄ−は両立性の非配位性アニオンを表し、但し、Ｍは、周期表第５族〜第１５族のいずれかに属する金属またはメタロイドを表し、Ｑは、各々独立して、ヒドリド、ハライド、炭素数２〜２０のジヒドロカルビルアミド基、炭素数１〜３０のヒドロカルビルオキシ基、炭素数１〜３０の炭化水素基、及び炭素数１〜４０の置換された炭化水素基からなる群より選ばれ、但し、上記（７）式中で各々独立に選ばれるＱの中でハライドであるＱの数は０又は１であり、ｍは１〜７の整数であり、ｐは２〜１４の整数であり、ｄは上で定義した通りであり、ｐ−ｍ＝ｄである。）
で表される少なくとも１種の化合物を用いて形成されたものである、上記１１〜１３項のいずれか１項に記載の方法。
［１５］水素添加能を有する化合物（Ｄ）が、チタノセン化合物単独、ハーフチタノセン化合物単独、又は、有機リチウム、有機マグネシウム、有機アルミニウムから選ばれる１種以上の有機金属化合物とチタノセン化合物又はハーフチタノセン化合物との反応混合物である、上記１１項記載の方法。
［１６］チタノセン化合物又はハーフチタノセン化合物が、下記式（８）：

（式中、Ｌは、各々独立して、シクロペンタジエニル基、インデニル基、テトラヒドロインデニル基、フルオレニル基、テトラヒドロフルオレニル基、及びオクタヒドロフルオレニル基からなる群より選ばれる環状η結合性アニオン配位子を表し、該配位子は場合によっては１〜８個の置換基を有し、該置換基は各々独立して炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基であり、
Ｔｉは、形式酸化数が＋２、＋３または＋４であって、少なくとも１つの配位子Ｌにη^５結合しているチタンを表し、
Ｗは、１〜５０個の非水素原子を有する２価の置換基であって、ＬとＴｉとに各々１価ずつの価数で結合し、これによりＬ及びＴｉと共働してメタラサイクルを形成する２価の置換基を表し、
ＸおよびＸ’は、各々独立して、１価の配位子、Ｔｉと２価で結合する２価の配位子、及びＬとＴｉとに各々１価ずつの価数で結合する２価の配位子からなる群より選ばれる配位子であって、水素原子、炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する配位子を表し、
ｊは１または２であり、但し、ｊが２である時、場合によっては２つの配位子Ｌが、１〜２０個の非水素原子を有する２価の基を介して互いに結合し、該２価の基は炭素数１〜２０のヒドロカルバジイル基、炭素数１〜１２のハロヒドロカルバジイル基、炭素数１〜１２のヒドロカルビレンオキシ基、炭素数１〜１２のヒドロカルビレンアミノ基、シランジイル基、ハロシランジイル基、及びシリレンアミノ基からなる群より選ばれる基であり、
ｋは０または１であり、
ｐは０、１または２であり、但し、Ｘが１価の配位子、またはＬとＴｉとに結合している２価の配位子である場合、ｐはＴｉの形式酸化数より１以上小さい整数であり、またＸがＴｉにのみ結合している２価のアニオン性σ結合型配位子である場合、ｐはＴｉの形式酸化数より（ｊ＋１）以上小さい整数であり、
ｑは０、１または２である。）
で表される少なくとも１種の化合物である、上記１５項記載の方法。
［１７］上記１〜１０項のいずれか１項に記載の超高分子量エチレン系重合体から得られる成形体。
［１８］上記１〜１０項のいずれか１項に記載の超高分子量エチレン系重合体から得られる繊維。One of the objects of the present invention is to provide an ultrahigh molecular weight ethylene polymer having an improved balance between moldability and heat stability during molding. In the present specification and the appended claims, the term “ethylene polymer” refers to an ethylene homopolymer or a copolymer of ethylene and another olefin comonomer (that is, an ethylene copolymer). .
Another object of the present invention is to provide an ultrahigh molecular weight ethylene polymer having a reduced density, excellent transparency and flexibility due to the insertion of a comonomer.
Still another object of the present invention is to produce the above ultrahigh molecular weight ethylene polymer stably over a long period of time at an efficient temperature in an industrial process using a metallocene as a catalyst, hardly generating scale. Manufacturing method.
As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the molecular weight distribution of the ethylene copolymer is larger than 3 obtained with a normal metallocene catalyst, and the residual Ti amount obtained with a Ziegler-Natta catalyst. It has been found that an ultra-high molecular weight ethylene polymer smaller than the amount of Cl is excellent in the balance between moldability and heat stability during molding. Furthermore, as a result of examining the ultra-high molecular weight ethylene copolymer in which the comonomer is inserted in detail, it is possible to maintain the ultra-high molecular weight even when the comonomer insertion amount is increased, and as the molecular weight increases, the insertion amount of the comonomer increases. It was found that an ultrahigh molecular weight ethylene copolymer with greatly improved flexibility and transparency can be obtained. On the other hand, by combining a metallocene catalyst previously treated with a hydrogenating agent and a compound having hydrogenation ability, it was found that the ultra-high molecular weight ethylene polymer can be produced at an efficient temperature in an industrial process. The invention has been reached.
That is, the present invention is as follows.
[1] an ethylene homopolymer (A); and an ethylene copolymer (B),
a) 99.9 to 75.0% by weight of ethylene,
b) an α-olefin having 3 to 20 carbon atoms, a cyclic olefin having 3 to 20 carbon atoms, a compound represented by the formula CH ₂ ═CHR (where R is an aryl group having 6 to 20 carbon atoms), and The ethylene copolymer obtained by copolymerizing 0.1 to 25.0% by weight of a comonomer that is at least one olefin selected from the group consisting of linear, branched or cyclic dienes having 4 to 20 carbon atoms. Polymer (B);
An ethylene polymer that is any one of
i) viscosity average molecular weight is 1 million or more,
ii) the molecular weight distribution (Mw / Mn) is greater than 3, and
iii) Ti content in the polymer is 3 ppm or less, Cl content is 5 ppm or less,
An ultra high molecular weight ethylene polymer.
[2] The relationship between density ρ (g / cc) and crystallinity X (%) is expressed by the following formula (1):

2. The ultrahigh molecular weight ethylene polymer according to 1 above, satisfying
[3] The ultrahigh molecular weight ethylene polymer according to 1 or 2 above, wherein the amount of terminal vinyl groups is 0.02 (pieces / 1000 C) or less.
[4] The relationship between the density ρ (g / cc) and the viscosity average molecular weight Mv is represented by the following formula (2):

The ultrahigh molecular weight ethylene polymer according to any one of the above items 1 to 3, which satisfies
[5] The ultrahigh molecular weight ethylene polymer according to any one of the above items 1 to 4, wherein the density ρ is 0.850 to 0.925 g / cc.
[6] The ultrahigh molecular weight ethylene polymer according to any one of the above items 1 to 3 and 5, wherein HAZE, which is a transparency index measured according to ASTM D1003, is 70% or less.
[7] In the insertion amount distribution of the comonomer measured by GPC / FT-IR, the insertion amount of the comonomer increases as the molecular weight of the polymer increases. The ultrahigh molecular weight ethylene polymer described in 1.
[8] The molecular weight distribution profile is represented by the following formula (3) by GPC / FT-IR measurement:

(In the formula, Mt is one point represented by the molecular weight on the molecular weight distribution profile, and the profile shows the peak of the maximum intensity, and Mc is an arbitrary point represented by the molecular weight on the molecular weight distribution profile. .)
In the range defined by
The slope of the approximate straight line by the least square method of the comonomer concentration profile is the following formula (4):

(In the formula, Mc ¹ and Mc ² are two different arbitrary points Mc represented by molecular weights satisfying the formula (3), and C (Mc ¹ ) and C (Mc ² ) are respectively on the above approximate straight line. The comonomer concentration corresponding to Mc ¹ and Mc ² of
8. The ultrahigh molecular weight ethylene polymer according to the above 7, which satisfies the range defined by
[9] In the measurement of CFC, the total amount of polymer fractions extracted at a temperature lower by 10 ° C. or more than the temperature indicating the maximum extraction amount is 8% by weight or less based on the total extraction amount. 9. The ultrahigh molecular weight ethylene polymer according to any one of items 3 and 5-8.
[10] In the measurement of CFC, in extraction at an arbitrary temperature T (° C.) within the range between the first temperature indicating the maximum extraction amount and the second temperature 10 ° C. higher than the first temperature,
It is a single point expressed by the molecular weight on the molecular weight distribution profile indicated by the polymer temperature extracted at the arbitrary temperature T (° C.) and the polymer fraction extracted at the arbitrary temperature T (° C.). When the approximate line is obtained by processing the relationship with the point Mp (T) by the least square method, the approximate line is expressed by the following equation (5):

(Where T ¹ and T ² are two different arbitrary extraction temperatures T (° C.) in the range between the first temperature and the second temperature, and Mp (T ¹ ) and Mp (T ² ) Are molecular weights corresponding to T ¹ and T ² on the approximate line, respectively.)
And the total amount of polymer fractions extracted at a temperature 10 ° C. or more lower than the first temperature when measured by CFC is the polymer fraction extracted at the full range of temperatures in CFC measurement. 10. The ultrahigh molecular weight ethylene polymer according to 9 above, which is 8% by weight or less based on the total amount.
[11] The method for producing an ultrahigh molecular weight ethylene polymer according to any one of the above items 1 to 10, wherein the metallocene system is brought into contact with a hydrogenating agent in advance when polymerizing one or more olefins. The said method using the compound (D) which has a catalyst (C) and hydrogenation ability.
[12] The hydrogenating agent is hydrogen and / or at least one type of R _n SiH _4-n (wherein 0 ≦ n ≦ 1, R is an alkyl group having 1 to 4 carbon atoms, and 6 to 12 carbon atoms) It is a hydrocarbon group selected from the group consisting of an aryl group, an alkylaryl group having 7 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, and an alkenyl group having 2 to 20 carbon atoms. 12. The method according to 11 above.
[13] The metallocene catalyst (C) is represented by the following formula (6):

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anionic ligand, and the ligand optionally has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, carbon A halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, and a hydrocarbyl phosphine having 1 to 12 carbon atoms 1 to 20 non-chosen selected from the group consisting of a fino group, a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group Is a substituent having an atom,
M is a transition metal selected from the group of transition metals belonging to Group 4 of the periodic table having a formal oxidation number of +2, +3, or +4, and represents a transition metal bonded to at least one ligand L by η ^5. ,
W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and M with a valence of 1 each, thereby cooperating with L and M to form a metallacycle. Represents a divalent substituent that forms
X is each independently a monovalent anionic σ-bonded ligand, a divalent anionic σ-bonded ligand that binds to M bivalently, and L and M each monovalently An anionic σ-bonded ligand having 1 to 60 non-hydrogen atoms, selected from the group consisting of divalent anionic σ-bonded ligands bonded by a valence;
X ′ each independently represents a neutral Lewis base coordination compound having 1 to 40 non-hydrogen atoms,
j is 1 or 2, provided that when j is 2, in some cases, two ligands L are bonded to each other through a divalent group having 1 to 20 non-hydrogen atoms, The divalent group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, and a hydrocarbyleneamino group having 1 to 12 carbon atoms. A group selected from the group consisting of a group, a silanediyl group, a halosilanediyl group, and a silyleneamino group,
k is 0 or 1,
p is 0, 1 or 2, provided that X is a monovalent anionic σ-bonded ligand or a divalent anionic σ-bonded ligand bonded to L and M , P is an integer 1 or more smaller than the formal oxidation number of M, and when X is a divalent anionic σ-bonded ligand bonded only to M, p is smaller than the formal oxidation number of M ( j + 1) an integer smaller than or equal to
q is 0, 1 or 2. )
12. The method according to 11 above, which is formed using at least one compound represented by the formula:
[14] The metallocene catalyst (C) is represented by the following formula (7):

(Wherein [L-H] ^{d +} represents a proton-donating Bronsted acid, wherein L represents a neutral Lewis base, d is an integer of 1 to 7; [M _m Q _p ] ^{d -} represents a non-coordinating anion of compatibility, where, M represents a metal or metalloid belonging to any of the fifth to group 15 of the periodic table, Q is each independently hydride, halide, Selected from the group consisting of a dihydrocarbylamide group having 2 to 20 carbon atoms, a hydrocarbyloxy group having 1 to 30 carbon atoms, a hydrocarbon group having 1 to 30 carbon atoms, and a substituted hydrocarbon group having 1 to 40 carbon atoms. However, in the above formula (7), each Q independently selected from Q is 0 or 1, m is an integer of 1 to 7, and p is an integer of 2 to 14. And d is as defined above, and pm = d.)
14. The method according to any one of 11 to 13 above, which is formed using at least one compound represented by the formula:
[15] The compound (D) having hydrogenation ability is a titanocene compound alone, a half titanocene compound alone, or one or more organometallic compounds selected from organic lithium, organic magnesium, and organic aluminum, and a titanocene compound or a half titanocene compound. 12. The method according to 11 above, wherein the reaction mixture is
[16] The titanocene compound or the half titanocene compound is represented by the following formula (8):

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anionic ligand, and the ligand optionally has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, carbon A halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, and a hydrocarbyl phosphine having 1 to 12 carbon atoms 1 to 20 non-chosen selected from the group consisting of a fino group, a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group Is a substituent having an atom,
Ti represents titanium having a formal oxidation number of +2, +3, or +4 and η ⁵ bonded to at least one ligand L;
W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and Ti at a valence of 1 each, thereby cooperating with L and Ti to form a metallacycle. Represents a divalent substituent that forms
X and X ′ are each independently a monovalent ligand, a divalent ligand that binds divalently to Ti, and a divalent bond that binds to L and Ti each with a monovalent valence. A ligand selected from the group consisting of: a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Aminohydrocarbyl group, hydrocarbyloxy group having 1 to 12 carbon atoms, dihydrocarbylamino group having 1 to 12 carbon atoms, hydrocarbylphosphino group having 1 to 12 carbon atoms, silyl group, aminosilyl group, hydrocarbyl having 1 to 12 carbon atoms Represents a ligand having 1 to 20 non-hydrogen atoms selected from the group consisting of an oxysilyl group and a halosilyl group;
j is 1 or 2, provided that when j is 2, in some cases, two ligands L are bonded to each other through a divalent group having 1 to 20 non-hydrogen atoms, The divalent group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, and a hydrocarbyleneamino group having 1 to 12 carbon atoms. A group selected from the group consisting of a group, a silanediyl group, a halosilanediyl group, and a silyleneamino group,
k is 0 or 1,
p is 0, 1 or 2, provided that when X is a monovalent ligand or a divalent ligand bonded to L and Ti, p is 1 from the formal oxidation number of Ti. When X is a divalent anionic σ-bonded ligand bonded only to Ti, p is an integer smaller than (j + 1) or more than the formal oxidation number of Ti,
q is 0, 1 or 2. )
16. The method according to 15 above, which is at least one compound represented by the formula:
[17] A molded product obtained from the ultrahigh molecular weight ethylene polymer according to any one of 1 to 10 above.
[18] A fiber obtained from the ultrahigh molecular weight ethylene polymer according to any one of 1 to 10 above.

（式中、Ｌは、各々独立して、シクロペンタジエニル基、インデニル基、テトラヒドロインデニル基、フルオレニル基、テトラヒドロフルオレニル基、及びオクタヒドロフルオレニル基からなる群より選ばれる環状η結合性アニオン配位子を表し、該配位子は場合によっては１〜８個の置換基を有し、該置換基は各々独立して炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基であり、
Ｍは、形式酸化数が＋２、＋３または＋４の周期表第４族に属する遷移金属群から選ばれる遷移金属であって、少なくとも１つの配位子Ｌにη^５結合している遷移金属を表し、
Ｗは、１〜５０個の非水素原子を有する２価の置換基であって、ＬとＭとに各各１価ずつの価数で結合し、これによりＬ及びＭと共働してメタラサイクルを形成する２価の置換基を表し、
Ｘは、各々独立して、１価のアニオン性σ結合型配位子、Ｍと２価で結合する２価のアニオン性σ結合型配位子、及びＬとＭとに各々１価ずつの価数で結合する２価のアニオン性σ結合型配位子からなる群より選ばれる、１〜６０個の非水素原子を有するアニオン性σ結合型配位子を表し、
Ｘ’は、各々独立して、１〜４０個の非水素原子を有する中性ルイス塩基配位性化合物を表し、
ｊは１または２であり、但し、ｊが２である時、場合によっては２つの配位子Ｌが、１〜２０個の非水素原子を有する２価の基を介して互いに結合し、該２価の基は炭素数１〜２０のヒドロカルバジイル基、炭素数１〜１２のハロヒドロカルバジイル基、炭素数１〜１２のヒドロカルビレンオキシ基、炭素数１〜１２のヒドロカルビレンアミノ基、シランジイル基、ハロシランジイル基、及びシリレンアミノ基からなる群より選ばれる基であり、
ｋは０または１であり、
ｐは０、１または２であり、但し、Ｘが１価のアニオン性σ結合型配位子、またはＬとＭとに結合している２価のアニオン性σ結合型配位子である場合、ｐはＭの形式酸化数より１以上小さい整数であり、またＸがＭにのみ結合している２価のアニオン性σ結合型配位子である場合、ｐはＭの形式酸化数より（ｊ＋１）以上小さい整数であり、
ｑは０、１または２である。）
上記式（１）の化合物中の配位子Ｘの例としては、ハライド、炭素数１〜６０の炭化水素基、炭素数１〜６０のヒドロカルビルオキシ基、炭素数１〜６０のヒドロカルビルアミド基、炭素数１〜６０のヒドロカルビルホスフィド基、炭素数１〜６０のヒドロカルビルスルフィド基、シリル基、これらの複合基等が挙げられる。
上記式（１）の化合物中の中性ルイス塩基配位性化合物Ｘ’の例としては、ホスフィン、エーテル、アミン、炭素数２〜４０のオレフィン、炭素数１〜４０のジエン、これらの化合物から誘導される２価の基等が挙げられる。
本発明において、環状η結合性アニオン配位子を有する遷移金属化合物としては、前記式（１）（ただし、ｊ＝１）で表される遷移金属化合物が好ましい。
前記式（１）（ただし、ｊ＝１）で表される化合物の好ましい例としては、下記の式（３）で表される化合物が挙げられる。

（式中、Ｍは、チタン、ジルコニウム及びハフニウムからなる群より選ばれる遷移金属であって、形式酸化数が＋２、＋３または＋４である遷移金属を表し、
Ｒ^５は、各々独立して、水素原子、炭素数１〜８の炭化水素基、シリル基、ゲルミル基、シアノ基、ハロゲン原子及びこれらの複合基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基を表し、但し、該置換基Ｒ^５が炭素数１〜８の炭化水素基、シリル基またはゲルミル基である時、場合によっては２つの隣接する置換基Ｒ^５が互いに結合して２価の基を形成し、これにより該２つの隣接する該置換基Ｒ^５にそれぞれ結合するシクロペンタジエニル環の２つの炭素原子間の結合と共働して環を形成し、
Ｘ”は、各々独立して、ハライド、炭素数１〜２０の炭化水素基、炭素数１〜１８のヒドロカルビルオキシ基、炭素数１〜１８のヒドロカルビルアミノ基、シリル基、炭素数１〜１８のヒドロカルビルアミド基、炭素数１〜１８のヒドロカルビルホスフィド基、炭素数１〜１８のヒドロカルビルスルフィド基及びこれらの複合基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基を表し、但し、場合によっては２つの置換基Ｘ”が共働して炭素数４〜３０の中性共役ジエンまたは２価の基を形成し、
Ｙ’は、−Ｏ−、−Ｓ−、−ＮＲ^＊−または−ＰＲ^＊−を表し、但し、Ｒ^＊は、水素原子、炭素数１〜１２の炭化水素基、炭素数１〜８のヒドロカルビルオキシ基、シリル基、炭素数１〜８のハロゲン化アルキル基、炭素数６〜２０のハロゲン化アリール基、またはこれらの複合基を表し、
ＺはＳｉＲ^＊ _２、ＣＲ^＊ _２、ＳｉＲ^＊ _２ＳｉＲ^＊ _２、ＣＲ^＊ _２ＣＲ^＊ _２、ＣＲ^＊＝ＣＲ^＊、ＣＲ^＊ _２ＳｉＲ^＊ _２またはＧｅＲ^＊ _２を表し、但し、Ｒ^＊は上で定義した通りであり、
ｎは１、２または３である。）
本発明において用いられる環状η結合性アニオン配位子を有する遷移金属化合物の具体例としては、以下に示すような化合物が挙げられる。
ビス（メチルシクロペンタジエニル）ジルコニウムジメチル、ビス（ｎ−ブチルシクロペンタジエニル）ジルコニウムジメチル、ビス（インデニル）ジルコニウムジメチル、ビス（１，３−ジメチルシクロペンタジエニル）ジルコニウムジメチル、
（ペンタメチルシクロペンタジエニル）（シクロペンタジエニル）ジルコニウムジメチル、ビス（シクロペンタジエニル）ジルコニウムジメチル、ビス（ペンタメチルシクロペンタジエニル）ジルコニウムジメチル、
ビス（フルオレニル）ジルコニウムジメチル、エチレンビス（インデニル）ジルコニウムジメチル、エチレンビス（４，５，６，７−テトラヒドロ−１−インデニル）ジルコニウムジメチル、エチレンビス（４−メチル−１−インデニル）ジルコニウムジメチル、エチレンビス（５−メチル−１−インデニル）ジルコニウムジメチル、
エチレンビス（６−メチル−１−インデニル）ジルコニウムジメチル、エチレンビス（７−メチル−１−インデニル）ジルコニウムジメチル、エチレンビス（５−メトキシ−１−インデニル）ジルコニウムジメチル、エチレンビス（２，３−ジメチル−１−インデニル）ジルコニウムジメチル、エチレンビス（４，７−ジメチル−１−インデニル）ジルコニウムジメチル、エチレンビス−（４，７−ジメトキシ−１−インデニル）ジルコニウムジメチル、メチレンビス（シクロペンタジエニル）ジルコニウムジメチル、
イソプロピリデン（シクロペンタジエニル）ジルコニウムジメチル、イソプロピリデン（シクロペンタジエニル−フルオレニル）ジルコニウムジメチル、
シリレンビス（シクロペンタジエニル）ジルコニウムジメチル、ジメチルシリレン（シクロペンタジエニル）ジルコニウムジメチル、［（Ｎ−ｔ−ブチルアミド）（テトラメチル−η^５−シクロペンタジエニル）−１，２−エタンジイル］チタニウムジメチル、［（Ｎ−ｔ−ブチルアミド）（テトラメチル−η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、
［（Ｎ−メチルアミド）（テトラメチル−η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−フェニルアミド）（テトラメチル−η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−ベンジルアミド）（テトラメチル−η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−ｔ−ブチルアミド）（η^５−シクロペンタジエニル）−１，２−エタンジイル］チタニウムジメチル、
［（Ｎ−ｔ−ブチルアミド）（η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−メチルアミド）（η^５−シクロペンタジエニル）−１，２−エタンジイル］チタニウムジメチル、［（Ｎ−メチルアミド）（η^５−シクロペンタジエニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−ｔ−ブチルアミド）（η^５−インデニル）ジメチルシラン］チタニウムジメチル、［（Ｎ−ベンジルアミド）（η^５−インデニル）ジメチルシラン］チタニウムジメチル、
ジブロモビストリフェニルホスフィンニッケル、ジクロロビストリフェニルホスフィンニッケル、ジブロモジアセトニトリルニッケル、ジブロモジベンゾニトリルニッケル、ジブロモ（１，２−ビスジフェニルホスフィノエタン）ニッケル、ジブロモ（１，３−ビスジフェニルホスフィノプロパン）ニッケル、ジブロモ（１，１’−ジフェニルビスホスフィノフェロセン）ニッケル、ジメチルビスジフェニルホスフィンニッケル、ジメチル（１，２−ビスジフェニルホスフィノエタン）ニッケル、メチル（１，２−ビスジフェニルホスフィノエタン）ニッケルテトラフルオロボレート、（２−ジフェニルホスフィノ−１−フェニルエチレンオキシ）フェニルピリジンニッケル、ジクロロビストリフェニルホスフィンパラジウム、ジクロロジベンゾニトリルパラジウム、ジクロロジアセトニトリルパラジウム、ジクロロ（１，２−ビスジフェニルホスフィノエタン）パラジウム、ビストリフェニルホスフィンパラジウムビステトラフルオロボレート、ビス（２，２’−ビピリジン）メチル鉄テトラフルオロボレートエーテラート等。
本発明において用いられる環状η結合性アニオン配位子を有する遷移金属化合物の具体例としては、さらに、上に挙げた各ジルコニウム及びチタン化合物の名称の「ジメチル」の部分（これは、各化合物の名称末尾の部分、すなわち「ジルコニウム」または「チタニウム」という部分の直後に現れているものであり、前記式（３）中のＸ”の部分に対応する名称である）を、以下に掲げる任意のものに替えてできる名称を持つ化合物も挙げられる。
「ジクロル」、「ジブロム」、「ジヨード」、「ジエチル」、「ジブチル」、「ジフェニル」、「ジベンジル」、「２−（Ｎ，Ｎ−ジメチルアミノ）ベンジル」、「２−ブテン−１，４−ジイル」、「ｓ−トランス−η^４−１，４−ジフェニル−１，３−ブタジエン」、「ｓ−トランス−η^４−３−メチル−１，３−ペンタジエン」、「ｓ−トランス−η^４−１，４−ジベンジル−１，３−ブタジエン」、「ｓ−トランス−η^４−２，４−ヘキサジエン」、「ｓ−トランス−η^４−１，３−ペンタジエン」、「ｓ−トランス−η^４−１，４−ジトリル−１，３−ブタジエン」、「ｓ−トランス−η^４−１，４−ビス（トリメチルシリル）−１，３−ブタジエン」、
「ｓ−シス−η^４−１，４−ジフェニル−１，３−ブタジエン」、「ｓ−シス−η^４−３−メチル−１，３−ペンタジエン」、「ｓ−シス−η^４−１，４−ジベンジル−１，３−ブタジエン」、「ｓ−シス−η^４−２，４−ヘキサジエン」、「ｓ−シス−η^４−１，３−ペンタジエン」、「ｓ−シス−η^４−１，４−ジトリル−１，３−ブタジエン」、「ｓ−シス−η^４−１，４−ビス（トリメチルシリル）−１，３−ブタジエン」等。
本発明において用いられる環状η結合性アニオン配位子を有する遷移金属化合物は、一般に公知の方法で合成できる。これら遷移金属化合物は単独で使用してもよいし組み合わせて使用してもよい。
次に本発明において用いられる遷移金属化合物と反応して触媒活性を発現する錯体を形成可能な活性化剤（本発明において以下単に「活性化剤」と称することがある）について説明する。
本発明における活性化剤として例えば、以下の一般式（２）で定義される化合物が挙げられる。

（式中、［Ｌ−Ｈ］^ｄ＋はプロトン供与性のブレンステッド酸を表し、但し、Ｌは中性のルイス塩基を表し、ｄは１〜７の整数であり；［Ｍ_ｍＱ_ｐ］^ｄ−は両立性の非配位性アニオンを表し、但し、Ｍは、周期表第５族〜第１５族のいずれかに属する金属またはメタロイドを表し、Ｑは、各々独立して、ヒドリド、ハライド、炭素数２〜２０のジヒドロカルビルアミド基、炭素数１〜３０のヒドロカルビルオキシ基、炭素数１〜３０の炭化水素基、及び炭素数１〜４０の置換された炭化水素基からなる群より選ばれ、但し、上記（２）式中で各々独立に選ばれるＱの中でハライドであるＱの数は０又は１であり、ｍは１〜７の整数であり、ｐは２〜１４の整数であり、ｄは上で定義した通りであり、ｐ−ｍ＝ｄである。）
非配位性アニオンの具体例としては、例えば、テトラキスフェニルボレート、トリ（ｐ−トリル）（フェニル）ボレート、トリス（ペンタフルオロフェニル）（フェニル）ボレート、トリス（２，４−ジメチルフェニル）（ヒドフェニル）ボレート、トリス（３，５−ジメチルフェニル）（フェニル）ボレート、トリス（３，５−ジ−トリフルオロメチルフェニル）（フェニル）ボレート、トリス（ペンタフルオロフェニル）（シクロヘキシル）ボレート、トリス（ペンタフルオロフェニル）（ナフチル）ボレート、テトラキス（ペンタフルオロフェニル）ボレート、トリフェニル（ヒドロキシフェニル）ボレート、ジフェニル−ジ（ヒドロキシフェニル）ボレート、トリフェニル（２，４−ジヒドロキシフェニル）ボレート、トリ（ｐ−トリル）（ヒドロキシフェニル）ボレート、トリス（ペンタフルオロフェニル）（ヒドロキシフェニル）ボレート、トリス（２，４−ジメチルフェニル）（ヒドロキシフェニル）ボレート、トリス（３，５−ジメチルフェニル）（ヒドロキシフェニル）ボレート、トリス（３，５−ジ−トリフルオロメチルフェニル）（ヒドロキシフェニル）ボレート、トリス（ペンタフルオロフェニル）（２−ヒドロキシエチル）ボレート、トリス（ペンタフルオロフェニル）（４−ヒドロキシブチル）ボレート、トリス（ペンタフルオロフェニル）（４−ヒドロキシ−シクロヘキシル）ボレート、トリス（ペンタフルオロフェニル）（４−（４’−ヒドロキシフェニル）フェニル）ボレート、トリス（ペンタフルオロフェニル）（６−ヒドロキシ−２−ナフチル）ボレート等が挙げられる。
他の好ましい非配位性アニオンの例としては、上記例示のボレートのヒドロキシ基がＮＨＲ基で置き換えられたボレートが挙げられる。ここで、Ｒは好ましくは、メチル基、エチル基またはｔｅｒｔ−ブチル基である。
また、プロトン付与性のブレンステッド酸の具体例としては、例えば、トリエチルアンモニウム、トリプロピルアンモニウム、トリ（ｎ−ブチル）アンモニウム、トリメチルアンモニウム、トリブチルアンモニウム及びトリ（ｎ−オクチル）アンモニウム等のようなトリアルキル基置換型アンモニウムカチオンが挙げられ、また、Ｎ，Ｎ−ジメチルアニリニウム、Ｎ，Ｎ−ジエチルアニリニウム、Ｎ，Ｎ−２，４，６−ペンタメチルアニリニウム、Ｎ，Ｎ−ジメチルベンジルアニリニウム等のようなＮ，Ｎ−ジアルキルアニリニウムカチオンも好適である。
さらに、ジ−（ｉ−プロピル）アンモニウム、ジシクロヘキシルアンモニウム等のようなジアルキルアンモニウムカチオンも好適であり、トリフェニルフォスフォニウム、トリ（メチルフェニル）ホスホニウム、トリ（ジメチルフェニル）ホスホニウム等のようなトリアリールホスホニウムカチオン、またはジメチルスルホニウム、ジエチルフルホニウム、ジフェニルスルホニウム等も好適である。
また本発明において活性化剤として次の式（４）で表されるユニットを有する有機金属オキシ化合物も用いることができる。

（但し、Ｍ^２は周期律表第１３族〜第１５族の金属またはメタロイドであり、Ｒは各々独立に炭素数１〜１２の炭化水素基又は置換炭化水素基であり、ｎは金属Ｍ^２の価数であり、ｍは２以上の整数である。）
本発明の活性化剤の好ましい例は、例えば次式（５）で示されるユニットを含む有機アルミニウムオキシ化合物である。

（但し、Ｒは炭素数１〜８のアルキル基であり、ｍは２〜６０の整数である。）
本発明の活性化剤の更に好ましい例は、例えば次式（６）で示されるユニットを含むメチルアルモキサンである。

（但し、ｍは２〜６０の整数である。）
本発明においては、活性化剤成分を単独で使用してもよいし組み合わせて使用してもよい。
本発明に於いて、これらの触媒成分は、固体成分に担持して担持型触媒としても用いることができる。このような固体成分としては、例えば、ポリエチレン、ポリプロピレンまたはスチレンジビニルベンゼンのコポリマー等の多孔質高分子材料、或いは例えばシリカ、アルミナ、マグネシア、塩化マグネシウム、ジルコニア、チタニア、酸化硼素、酸化カルシウム、酸化亜鉛、酸化バリウム、五酸化バナジウム、酸化クロム及び酸化トリウム等のような周期律表第２、３、４、１３及び１４族元素の無機固体材料、及びそれらの混合物、並びにそれらの複合酸化物から選ばれる少なくとも１種の無機固体材料が挙げられる。
シリカの複合酸化物としては、例えばシリカマグネシア、シリカアルミナ等のようなシリカと周期律表第２族または第１３族元素との複合酸化物が挙げられる。また、上記二つの触媒成分の他に、必要に応じて有機アルミニウム化合物を触媒成分として用いることができる。本発明において用いることができる有機アルミニウム化合物とは、例えば次式（７）で表される化合物である。

（但し、Ｒは炭素数１〜１２までのアルキル基、炭素数６〜２０のアリール基であり、Ｘはハロゲン、水素またはアルコキシル基であり、アルキル基は直鎖状、分岐状または環状であり、ｎは１〜３の整数である。）
本発明の有機アルミニウム化合物は、上記一般式（７）で表される化合物の混合物であっても構わない。例えば上記一般式中のＲとして、メチル基、エチル基、ブチル基、イソブチル基、ヘキシル基、オクチル基、デシル基、フェニル基、トリル基等が挙げられ、またＸとしては、メトキシ基、エトキシ基、ブトキシ基、クロル等が挙げられる。
本発明で用いられる有機アルミニウム化合物の具体例としては、トリメチルアルミニウム、トリエチルアルミニウム、トリブチルアルミニウム、トリイソブチルアルミニウム、トリヘキシルアルミニウム、トリオクチルアルミニウム、トリデシルアルミニウム等、或いはこれらの有機アルミニウムとメチルアルコール、エチルアルコール、ブチルアルコール、ペンチルアルコール、ヘキシルアルコール、オクチルアルコール、デシルアルコール等のアルコール類との反応生成物、例えばジメチルメトキシアルミニウム、ジエチルエトキシアルミニウム、ジブチルブトキシアルミニウム等が挙げられる。
次に本発明において用いられる水素化剤について説明する。
水素化剤としては例えば、水素、Ｒ_ｒ−ｎ（Ｍｔ）_αＨ_ｎ（式中、Ｍｔは周期律表第１〜３族及び１４、１５族に属する原子であり、Ｒは炭素原子数１〜４のアルキル基、炭素原子数６〜１２のアリール基、炭素原子数７〜２０のアルキルアリール基、炭素原子数７〜２０のアリールアルキル基、炭素原子数２〜２０のアルケニル基からなる群より選ばれる炭化水素基であり、ｎ＞０、ｒ−ｎ≧０、ｒはＭｔの原子価）が挙げられる。
これらの中で、好ましいものは水素またはＲ_ｎＳｉＨ_４−ｎ（式中、０≦ｎ≦１、Ｒは炭素原子数１〜４のアルキル基、炭素原子数６〜１２のアリール基、炭素原子数７〜２０のアルキルアリール基、炭素原子数７〜２０のアリールアルキル基、炭素原子数２〜２０のアルケニル基からなる群より選ばれる炭化水素基である。）で表されるシラン化合物であり、特に水素が好ましい。
水素化剤の具体例としては、例えば、水素、ナトリウムハイドライド、カルシウムハイドライド、水素化リチウムアルミニウム、ＳｉＨ_４、メチルシラン、エチルシラン、ｎ−ブチルシラン、オクチルシラン、オクタデシルシラン、フェニルシラン、ベンジルシラン、ジメチルシラン、ジエチルシラン、ジｎ−ブチルシラン、ジオクチルシラン、ジオクタデシルシラン、ジフェニルシラン、ジベンジルシラン、エテニルシラン、３−ブテニルシラン、５−ヘキセニルシラン、シクロヘキセニルシラン、７−オクテニルシラン、１７−オクタデセニルシラン、等が挙げられ、好ましくは水素またはオクチルシランまたはフェニルシランである。
本発明においては、これらの水素化剤を単独で使用してもよいし組み合わせて使用してもよい。
メタロセン系触媒（Ｃ）は予め水素化剤と接触させてから重合に使用する。メタロセン系触媒を重合反応器に導入する前に水素化剤とを接触させる方法としては、例えば１）触媒移送用の媒体に水素化剤を含有させ、触媒を重合反応器に移送中に触媒と水素化剤とを接触させる方法、２）触媒を移送する前の段階、例えば触媒貯槽等に水素化剤を導入し、触媒と水素化剤とを接触させる方法、等が挙げられる。
上記１）の方法としては、例えば、重合反応器に触媒を導入するために設けられた触媒移送ラインに、水素化剤の供給ラインを接続し、水素化剤を該ラインに供給することにより、該媒体に水素化剤を含有させることができる。或いは、重合反応器に触媒を導入するために設けられた重合反応器内部の触媒供給ノズルに、水素化剤の供給ラインを接続し、水素化剤を該ラインに供給することにより該媒体に水素化剤を含有させることができる。また、触媒を重合反応器へ移送する媒体に予め水素化剤を含有させておき、触媒を該水素化剤含有触媒移送用の媒体を用いて重合反応器へ移送してもよい。
上記２）の方法の場合は、接触時間は特に限定されるものではないが、好ましくは１０分以内、より好ましくは５分以内、さらに好ましくは１分以内、さらにまた好ましくは３０秒以内、最も好ましくは２０秒以内である。
本発明で、メタロセン系触媒と接触させる水素化剤の量は、該触媒に含まれる遷移金属化合物の０．５倍モル以上且つ５００００倍モル以下である。水素化剤の量が０．５倍モル未満であると、塊状のポリマーが生成し、安定運転が困難となる。また、水素化剤の量が５００００倍モルよりも多ければ、重合活性と分子量の低下を招く。水素化剤の量は、好ましくは１倍モル以上且つ３００００倍モル以下であり、より好ましくは１０倍モル以上且つ１０００倍モル以下である。
次に、本発明において用いられる水素添加能を有する化合物（Ｄ）について説明する。水素添加能を有する化合物としては、水素と反応し、系内のエチレンまたはα−オレフィンを水素添加し、結果的に重合反応リアクター内の水素濃度を低下させることのできる化合物であり、好ましくは重合触媒活性を低下させない化合物であればよい。メタロセン化合物や白金、パラジウム、パラジウム−クロム、ニッケル、ルテニウムを含有する化合物を使用することができる。その中でも水素添加活性能の高いメタロセン化合物が好ましく、とりわけ重合温度付近で水素添加活性能を発現できるチタノセン化合物あるいはハーフチタノセン化合物が特に好ましい。
これらのチタノセン化合物あるいはハーフチタノセン化合物は単独でも水素添加活性能があるが、有機リチウム、有機マグネシウム、有機アルミニウム等の有機金属化合物と混合・反応させることによって水素添加活性能が高くなり、好ましい。
上記有機金属化合物とチタノセン化合物あるいはハーフチタノセン化合物との混合・反応は、重合リアクター内にフィードする前に行っても良いし、重合リアクター内に別々にフィードし、重合リアクター系内で行っても良い。
本発明において使用されるチタノセン化合物またはハーフチタノセン化合物は、例えば以下の一般式（８）で表すことができる。

（式中、Ｌは、各々独立して、シクロペンタジエニル基、インデニル基、テトラヒドロインデニル基、フルオレニル基、テトラヒドロフルオレニル基、及びオクタヒドロフルオレニル基からなる群より選ばれる環状η結合性アニオン配位子を表し、該配位子は場合によっては１〜８個の置換基を有し、該置換基は各々独立して炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する置換基であり、
Ｔｉは、形式酸化数が＋２、＋３または＋４であって、少なくとも１つの配位子Ｌにη^５結合しているチタンを表し、
Ｗは、１〜５０個の非水素原子を有する２価の置換基であって、ＬとＴｉとに各々１価ずつの価数で結合し、これによりＬ及びＴｉと共働してメタラサイクルを形成する２価の置換基を表し、
ＸおよびＸ’は、各々独立して、１価の配位子、Ｔｉと２価で結合する２価の配位子、及びＬとＴｉとに各々１価ずつの価数で結合する２価の配位子からなる群より選ばれる配位子であって、水素原子、炭素数１〜２０の炭化水素基、ハロゲン原子、炭素数１〜１２のハロゲン置換炭化水素基、炭素数１〜１２のアミノヒドロカルビル基、炭素数１〜１２のヒドロカルビルオキシ基、炭素数１〜１２のジヒドロカルビルアミノ基、炭素数１〜１２のヒドロカルビルホスフィノ基、シリル基、アミノシリル基、炭素数１〜１２のヒドロカルビルオキシシリル基、及びハロシリル基からなる群より選ばれる、１〜２０個の非水素原子を有する配位子を表し、
ｊは１または２であり、但し、ｊが２である時、場合によっては２つの配位子Ｌが、１〜２０個の非水素原子を有する２価の基を介して互いに結合し、該２価の基は炭素数１〜２０のヒドロカルバジイル基、炭素数１〜１２のハロヒドロカルバジイル基、炭素数１〜１２のヒドロカルビレンオキシ基、炭素数１〜１２のヒドロカルビレンアミノ基、シランジイル基、ハロシランジイル基、及びシリレンアミノ基からなる群より選ばれる基であり、
ｋは０または１であり、
ｐは０、１または２であり、但し、Ｘが１価の配位子、またはＬとＴｉとに結合している２価の配位子である場合、ｐはＴｉの形式酸化数より１以上小さい整数であり、またＸがＴｉにのみ結合している２価のアニオン性σ結合型配位子である場合、ｐはＴｉの形式酸化数より（ｊ＋１）以上小さい整数であり、
ｑは０、１または２である。）
本発明において用いられるチタノセン化合物の具体例としては、環状η結合性アニオン配位子をシクロペンタジエニル基とした場合、以下に示すような化合物が挙げられる。
ビス（シクロペンタジエニル）チタニウムジメチル、ビス（シクロペンタジエニル）チタニウムジエチル、ビス（シクロペンタジエニル）チタニウムジイソプロピル、ビス（シクロペンタジエニル）チタニウムジ−ｎ−ブチル、ビス（シクロペンタジエニル）チタニウムジ−ｓｅｃ−ブチル、ビス（シクロペンタジエニル）チタニウムジヘキシル、ビス（シクロペンタジエニル）チタニウムジオクチル、ビス（シクロペンタジエニル）チタニウムジメトキシド、ビス（シクロペンタジエニル）チタニウムジエトキシド、ビス（シクロペンタジエニル）チタニウムジイソプロポキシド、ビス（シクロペンタジエニル）チタニウムジブトキシド、ビス（シクロペンタジエニル）チタニウムジフェニル、ビス（シクロペンタジエニル）チタニウムジ−ｍ−トリル、ビス（シクロペンタジエニル）チタニウムジ−ｐ−トリル、ビス（シクロペンタジエニル）チタニウムジ−ｍ，ｐ−キシリル、ビス（シクロペンタジエニル）チタニウムジ−４−エチルフェニル、ビス（シクロペンタジエニル）チタニウムジ−４−ヘキシルフェニル、ビス（シクロペンタジエニル）チタニウムジ−４−メトキシフェニル、ビス（シクロペンタジエニル）チタニウムジ−４−エトキシフェニル、ビス（シクロペンタジエニル）チタニウムジフェノキシド、ビス（シクロペンタジエニル）チタニウムジフルオライド、ビス（シクロペンタジエニル）チタニウムジブロマイド、ビス（シクロペンタジエニル）チタニウムジクロライド、ビス（シクロペンタジエニル）チタニウムジブロマイド、ビス（シクロペンタジエニル）チタニウムジアイオダイド、ビス（シクロペンタジエニル）チタニウムクロライドメチル、ビス（シクロペンタジエニル）チタニウムクロライドエトキサイド、ビス（シクロペンタジエニル）チタニウムクロライドフェノキシド、ビス（シクロペンタジエニル）チタニウムジベンジル、ビス（シクロペンタジエニル）チタニウムジ−ジメチルアミド、ビス（シクロペンタジエニル）チタニウムジ−ジエチルアミド、ビス（シクロペンタジエニル）チタニウムジ−ジイソプロピルアミド、ビス（シクロペンタジエニル）チタニウムジ−ジ−ｓｅｃ−ブチルアミド、ビス（シクロペンタジエニル）チタニウムジ−ジ−ｔｅｒｔ−ブチルアミド、ビス（シクロペンタジエニル）チタニウムジ−ジトリメチルシリルアミド等。
本発明において用いられるチタノセン化合物の具体例としては、さらに、上に挙げた「シクロペンタジエニル」の部分を、以下に掲げる任意の環状η結合性アニオン配位子に替えてできる名称を持つ化合物も挙げられる。
「メチルシクロペンタジエニル」、「ｎ−ブチルシクロペンタジエニル」、「１，３−ジメチルシクロペンタジエニル」、「ペンタメチルシクロペンタジエニル」、「テトラメチルシクロペンタジエニル」、「トリメチルシリルシクロペンタジエニル」、「１，３−ビストリメチルシリルシクロペンタジエニル」、「インデニル」、「４，５，６，７−テトラヒドロ−１−インデニル」、「５−メチル−１−インデニル」、「６−メチル−１−インデニル」、「７−メチル−１−インデニル」、「５−メトキシ−１−インデニル」、「２，３−ジメチル−１−インデニル」、「４，７−ジメチル−１−インデニル」、「４，７−ジメトキシ−１−インデニル」、「フルオレニル」等。
さらに、チタノセン化合物を構成する２つの環状η結合性アニオン配位子は、上に示した配位子から任意に組み合わせることができる。任意に組み合わせた具体例としては、（ペンタメチルシクロペンタジエニル）（シクロペンタジエニル）チタニウムジクロライド、（フルオレニル）（シクロペンタジエニル）チタニウムジクロライド、（フルオレニル）（ペンタメチルシクロペンタジエニル）チタニウムジクロライド、（インデニル）（シクロペンタジエニル）チタニウムジクロライド、（インデニル）（ペンタメチルシクロペンタジエニル）チタニウムジクロライド、（インデニル）（フルオレニル）チタニウムジクロライド、（テトラヒドロインデニル）（シクロペンタジエニル）チタニウムジクロライド、（テトラヒドロインデニル）（ペンタメチルシクロペンタジエニル）チタニウムジクロライド、（テトラヒドロインデニル）（フルオレニル）チタニウムジクロライド、（シクロペンタジエニル）（１，３−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、（ペンタメチルシクロペンタジエニル）（１，３−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、（フルオレニル）（１，３−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、（インデニル）（１，３−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、（テトラヒドロインデニル）（１，３−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド等が挙げられる。また、これらの化合物の「ジクロライド」の部分を以下に掲げる任意のものに替えてできる名称を持つ化合物も挙げられる。
「ジブロマイド」、「ジアイオダイド」、「メチルクロライド」、「メチルブロマイド」、「ジメチル」、「ジエチル」、「ジブチル」、「ジフェニル」、「ジベンジル」、「ジメトキシ」、「メトキシクロライド」、「ビス−２−（Ｎ，Ｎ−ジメチルアミノ）ベンジル」、「２−ブテン−１，４−ジイル」、「ｓ−トランス−η^４−１，４−ジフェニル−１，３−ブタジエン」、「ｓ−トランス−η^４−３−メチル−１，３−ペンタジエン」、「ｓ−トランス−η^４−１，４−ジベンジル−１，３−ブタジエン」、「ｓ−トランス−η^４−２，４−ヘキサジエン」、「ｓ−トランス−η^４−１，３−ペンタジエン」、「ｓ−トランス−η^４−１，４−ジトリル−１，３−ブタジエン」、「ｓ−トランス−η^４−１，４−ビス（トリメチルシリル）−１，３−ブタジエン」、「ｓ−シス−η^４−１，４−ジフェニル−１，３−ブタジエン」、「ｓ−シス−η^４−３−メチル−１，３−ペンタジエン」、「ｓ−シス−η^４−１，４−ジベンジル−１，３−ブタジエン」、「ｓ−シス−η^４−２，４−ヘキサジエン」、「ｓ−ジス−η^４−１，３−ペンタジエン」、「ｓ−シス−η^４−１，４−ジトリル−１，３−ブタジエン」、「ｓ−シス−η^４−１，４−ビス（トリメチルシリル）−１，３−ブタジエン」等。
この２つの環状η結合性アニオン配位子は以下に掲げる基を介して結合していても良い。
−ＳｉＲ^＊ _２−、−ＣＲ^＊ _２−、−ＳｉＲ^＊ _２ＳｉＲ^＊ _２−、−ＣＲ^＊ _２ＣＲ^＊ _２−、−ＣＲ^＊＝ＣＲ^＊−、−ＣＲ^＊ _２ＳｉＲ^＊ _２−、−ＧｅＲ^＊ _２−等。但し、Ｒ^＊は、水素原子、炭素数１〜１２の炭化水素基、炭素数１〜８のヒドロカルビルオキシ基、シリル基、炭素数１〜８のハロゲン化アルキル基、炭素数６〜２０のハロゲン化アリール基、またはこれらの複合基を表す。
２つの環状η結合性アニオン配位子が結合している具体例としては、エチレンビス（シクロペンタジエニル）チタニウムジクロライド、エチレンビス（テトラメチルシクロペンタジエニル）チタニウムジクロライド、エチレンビス（インデニル）チタニウムジクロライド、エチレンビス（４，５，６，７−テトラヒドロ−１−インデニル）チタニウムジクロライド、エチレンビス（４−メチル−１−インデニル）チタニウムジクロライド、エチレンビス（５−メチル−１−インデニル）チタニウムジクロライド、エチレンビス（６−メチル−１−インデニル）チタニウムジクロライド、エチレンビス（７−メチル−１−インデニル）チタニウムジクロライド、エチレンビス（５−メトキシ−１−インデニル）チタニウムジクロライド、エチレンビス（２，３−ジメチル−１−インデニル）チタニウムジクロライド、エチレンビス（４，７−ジメチル−１−インデニル）チタニウムジクロライド、エチレンビス（４，７−ジメトキシ−１−インデニル）チタニウムジクロライド、メチレンビス（シクロペンタジエニル）チタニウムジクロライド、イソプロピリデンビス（シクロペンタジエニル）チタニウムジクロライド、イソプロピリデン（シクロペンタジエニル）（フルオレニル）チタニウムジクロライド、シリレンビス（シクロペンタジエニル）チタニウムジクロライド、ジメチルシリレンビス（シクロペンタジエニル）チタニウムジクロライド、ジメチルシリレンビス（テトラメチルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレンビス（メチルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレンビス（トリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（シクロペンタジエニル）（フルオレニル）チタニウムジクロライド、ジメチルシリレン（シクロペンタジエニル）（インデニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（フルオレニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（インデニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（シクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（フルオレニル）（インデニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（トリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（３，５−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（シクロペンタジエニル）（トリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（テトラメチルシクロペンタジエニル）（３，５−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（フルオレニル）（トリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（フルオレニル）（３，５−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（インデニル）（トリメチルシリルシクロペンタジエニル）チタニウムジクロライド、ジメチルシリレン（インデニル）（３，５−ビストリメチルシリルシクロペンタジエニル）チタニウムジクロライド等が挙げられる。
本発明において用いられるハーフチタノセン化合物の具体例としては、環状η結合性アニオン配位子をシクロペンタジエニル基とした場合、以下に示すような化合物が挙げられる。
シクロペンタジエニルチタニウムトリメチル、シクロペンタジエニルチタニウムトリエチル、シクロペンタジエニルチタニウムトリイソプロピル、シクロペンタジエニルチタニウムトリ−ｎ−ブチル、シクロペンタジエニルチタニウムトリ−ｓｅｃ−ブチル、シクロペンタジエニルチタニウムトリメトキシド、シクロペンタジエニルチタニウムトリエトキシド、シクロペンタジエニルチタニウムトリイソプロポキシド、シクロペンタジエニルチタニウムトリブトキシド、シクロペンタジエニルチタニウムトリフェニル、シクロペンタジエニルチタニウムトリ−ｍ−トリル、シクロペンタジエニルチタニウムトリ−ｐ−トリル、シクロペンタジエニルチタニウムトリ−ｍ，ｐ−キシリル、シクロペンタジエニルチタニウムトリ−４−エチルフェニル、シクロペンタジエニルチタニウムトリ−４−ヘキシルフェニル、シクロペンタジエニルチタニウムトリ−４−メトキシフェニル、シクロペンタジエニルチタニウムトリ−４−エトキシフェニル、シクロペンタジエニルチタニウムトリフェノキシド、シクロペンタジエニルチタニウムトリフルオライド、シクロペンタジエニルチタニウムトリブロマイド、シクロペンタジエニルチタニウムトリクロライド、シクロペンタジエニルチタニウムトリブロマイド、シクロペンタジエニルチタニウムトリアイオダイド、シクロペンタジエニルチタニウムメチルジクロライド、シクロペンタジエニルチタニウムジメチルクロライド、シクロペンタジエニルチタニウムエトキサイドジクロライド、シクロペンタジエニルチタニウムジエトキサイドクロライド、シクロペンタジエニルチタニウムフェノキシドジクロライド、シクロペンタジエニルチタニウムジフェノキシドクロライド、シクロペンタジエニルチタニウムトリベンジル、シクロペンタジエニルチタニウムトリ−ジメチルアミド、シクロペンタジエニルチタニウムトリ−ジエチルアミド、シクロペンタジエニルチタニウムトリ−ジイソプロピルアミド、シクロペンタジエニルチタニウムトリ−ジ−ｓｅｃ−ブチルアミド、シクロペンタジエニルチタニウムトリ−ジ−ｔｅｒｔ−ブチルアミド、シクロペンタジエニルチタニウムトリ−ジトリメチルシリルアミド等。
本発明において用いられるハーフチタノセン化合物の具体例としては、さらに、上に挙げた「シクロペンタジエニル」の部分を、チタノセン化合物の具体例で掲げたのと同様に任意の環状η結合性アニオン配位子に替えてできる名称を持つ化合物も挙げられる。
さらに、以下に掲げるハーフチタノセン化合物も挙げられる。
［（Ｎ−ｔｅｒｔ−ブチルアミド）（テトラメチルシクロペンタジエニル）−１，２−エタンジイル］チタニウムジクロライド、［（Ｎ−ｔｅｒｔ−ブチルアミド）（テトラメチルシクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−メチルアミド）（テトラメチルシクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−フェニルアミド）（テトラメチルシクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−ベンジルアミド）（テトラメチルシクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−ｔｅｒｔ−ブチルアミド）（シクロペンタジエニル）−１，２−エタンジイル］チタニウムジクロライド、［（Ｎ−ｔｅｒｔ−ブチルアミド）（シクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−メチルアミド）（シクロペンタジエニル）−１，２−エタンジイル］チタニウムジクロライド、［（Ｎ−メチルアミド）（シクロペンタジエニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−ｔｅｒｔ−ブチルアミド）（インデニル）ジメチルシラン］チタニウムジクロライド、［（Ｎ−ベンジルアミド）（インデニル）ジメチルシラン］チタニウムジクロライド等。
また、これらのハーフチタノセン化合物の「ジクロライド」の部分をチタノセン化合物で掲げた任意のものに替えてできる名称を持つ化合物も挙げられる。
これらのチタノセン化合物またはハーフチタノセン化合物は単独であるいは組み合わせて用いることができる。これらの中で水素添加活性が高く、好ましい化合物としては、ビス（シクロペンタジエニル）チタニウムジクロライド、ビス（シクロペンタジエニル）チタニウムジ−ｍ−トリル、ビス（シクロペンタジエニル）チタニウムジ−ｐ−トリルが挙げられる。
また、上記チタノセン化合物またはハーフチタノセン化合物は有機リチウム、有機マグネシウム、有機アルミニウムと混合・反応させることで、水素添加活性をさらに向上させることができるので好ましい。
チタノセン化合物またはハーフチタノセン化合物と混合・反応させうる有機リチウムとして、ＲＬｉ（式中、Ｒは炭素数１〜１０のアルキル基、アルコキシ基またはアルキルアミド基、炭素数６〜１２のアリール基、アリロオキシ基またはアリールアミド基、炭素数７〜２０のアルキルアリール基、アルキルアリロオキシ基またはアルキルアリールアミド基、炭素数７〜２０のアリールアルキル基、アリールアルコキシ基、アリールアルキルアミド基、炭素数２〜２０のアルケニル基からなる群より選ばれる炭化水素基である。）で表される化合物が挙げられる。
このような有機リチウムの具体例としては、メチルリチウム、エチルリチウム、イソプロピルリチウム、ｎ−ブチルリチウム、ｓｅｃ−ブチルリチウム、ｔｅｒｔ−ブチルリチウム、メトキシリチウム、エトキシリチウム、イソプロポキシリチウム、ブトキシリチウム、ジメチルアミドリチウム、ジエチルアミドリチウム、ジイソプロピルアミドリチウム、ジブチルアミドリチウム、ジフェニルアミドリチウム、フェニルリチウム、ｍ−トリルリチウム、ｐ−トリルリチウム、キシリルリチウム、メトキシフェニルリチウム、フェノキシリチウム、４−メチルフェノキシリチウム、２，６−ジイソプロピルフェノキシリチウム、２，４，６−トリイソプロピルフェノキシリチウム、ベンジルリチウム等のモノリチウム化合物が挙げられる。
また、上記のモノリチウム化合物を開始剤として少量のモノマーを付加させた末端リビング活性を有するオリゴマー、例えば、ポリブタジエニルリチウム、ポリイソプレニルリチウム、ポリスチリルリチウム等も挙げられる。また、一分子内に２個以上のリチウムを有する化合物、例えば、ジイソプロペニルベンゼンとｓｅｃ−ブチルリチウムの反応生成物であるジリチウム化合物、ジビニルベンゼンとｓｅｃ−ブチルリチウムと少量の１，３−ブタジエンの反応生成物であるマルチリチウム化合物等も挙げられる。これらの有機リチウムは単独で、あるいは組み合わせて使用することもできる。チタノセン化合物またはハーフチタノセン化合物に対する添加量としては、Ｌｉ／Ｔｉ（モル比）で０．１〜１０の範囲が好ましい。さらに好ましくは、０．２〜５の範囲である。
チタノセン化合物またはハーフチタノセン化合物と混合・反応させうる有機マグネシウムとしては、ジアルキルマグネシウムやグリニャール試薬に代表されるアルキルハロゲンマグネシウム等が挙げられる。その具体例としては、ジメチルマグネシウム、ジエチルマグネシウム、ジブチルマグネシウム、エチルブチルマグネシウム、ジヘキシルマグネシウム、メチルマグネシウムブロマイド、メチルマグネシウムクロライド、エチルマグネシウムブロマイド、エチルマグネシウムクロライド、ブチルマグネシウムブロマイド、ブチルマグネシウムクロライド、ヘキシルマグネシウムブロマイド、シクロヘキシルマグネシウムブロマイド、フェニルマグネシウムブロマイド、フェニルマグネシウムクロライド、アリルマグネシウムブロマイド、アリルマグネシウムクロライド等が挙げられる。
これらの有機マグネシウムは単独で、あるいは組み合わせて使用することもできる。チタノセン化合物またはハーフチタノセン化合物に対する添加量としては、Ｍｇ／Ｔｉ（モル比）で０．１〜１０の範囲が好ましい。さらに好ましくは、０．２〜５の範囲である。
チタノセン化合物またはハーフチタノセン化合物と混合・反応させうる有機アルミニウムとしては、トリアルキルアルミニウムやジアルキルアルミニウムクロライド、アルキルマグネシウムジクロライド等が挙げられる。その具体例としては、トリメチルアルミニウム、トリエチルアルミニウム、トリブチルアルミニウム、トリイソブチルアルミニウム、トリヘキシルアルミニウム、トリオクチルアルミニウム、トリデシルアルミニウム、ジメチルアルミニウムクロライド、ジエチルアルミニウムクロライド、メチルアルミニウムジクロライド、エチルアルミニウムジクロライド、ジエチルエトキシアルミニウム等が使用できる。
これらの有機アルミニウムは単独で、あるいは組み合わせて使用することもできる。チタノセン化合物またはハーフチタノセン化合物に対する添加量としては、Ａｌ／Ｔｉ（モル比）で０．１〜１０の範囲が好ましい。さらに好ましくは、０．２〜５の範囲である。
これらの組み合わせの中でも、チタノセン化合物と有機アルミニウムとの混合・反応物はとりわけ水素添加能が高く、本発明において好適に使用できる。この場合、チタノセン化合物と有機アルミニウムとでメタラサイクルな化合物を形成し、Ｔｅｂｂｅ型錯体となっているものと推定される。チタノセン化合物としてチタノセンジクロライド、有機アルミニウムとしてトリメチルアルミニウムを選び、１：２（モル比）で混合・反応させて得られるＴｅｂｂｅ型錯体も水素添加能が高い。このＴｅｂｂｅ型錯体は、反応混合物から単離して得られたものを用いても、反応混合物をそのまま用いても良いが、反応混合物をそのまま用いる方法が単離する煩雑な作業を省略できるので工業的に有利である。
このようなチタノセン化合物と有機アルミニウムの反応は比較的ゆっくりとした反応であるため、十分な時間をかける必要がある。具体的には、チタノセン化合物を不活性溶媒中に分散または溶解し、有機アルミニウム化合物を加えて０℃から１００℃の温度で十分に攪拌して反応させる。反応温度は低すぎると時間がかかりすぎ、一方高すぎると副反応が起こりやすく、水素添加能が低下する。好ましくは１０℃から５０℃の温度である。又反応は２段階で進むため、好ましくは室温で１日以上の時間が必要である。
これらのチタノセン化合物またはハーフチタノセン化合物の水素添加能をさらに高めるために、アルコール類、エーテル類、アミン類、ケトン類、りん化合物等を第２成分あるいは第３成分として添加することもできる。
チタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるためのアルコール類の例としては、メチルアルコール、エチルアルコール、イソプロピルアルコール、ブチルアルコール、フェノールや、エチレングリコール等のグリコール類が挙げられる。
チタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるためのエーテル類の例としては、ジメチルエーテル、ジエチルエーテル、ジイソプロピルエーテル、ジブチルエーテル、テトラヒドロフラン、ジフェニルエーテル、エチレングリコールジメチルエーテル、エチレングリコールジエチルエーテル、エチレングリコールジブチルエーテル等のアルキルエーテル類、ビストリメチルシリルエーテル等のシリルエーテル類が挙げられる。
チタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるためのアミン類の例としては、ジメチルアミン、ジエチルアミン、ジイソプロピルアミン、ジブチルアミン、ジフェニルアミン等の２級アミンや、トリメチルアミン、トリエチルアミン、トリイソプロピルアミン、トリブチルアミン、トリフェニルアミン、Ｎ，Ｎ，Ｎ’，Ｎ’−テトラメチルエチレンジアミン等の３級アミン等が挙げられる。
チタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるためのケトン類の例としては、ジメチルケトン、ジエチルケトン、メチルエチルケトン、メチルフェニルケトン、エチルフェニルケトン等が挙げられる。
チタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるためのりん化合物の例としては、チタノセンに配位可能なりん化合物が挙げられ、例えば、トリメチルホスフィン、トリエチルホスフィン、トリフェニルホスフィン等が挙げられる。
これらのチタノセン化合物またはハーフチタノセン化合物の水素添加能を高めるための化合物は単独で、あるいは組み合わせて使用することもできる。チタノセン化合物またはハーフチタノセン化合物に対する添加量としては、Ｔｉに対するモル比で０．０１〜１０の範囲である。好ましくは、０．０２〜５の範囲である。さらに好ましくは、０．０２〜１の範囲である。
本発明の水素添加能を有する化合物（Ｄ）としては、上記のチタノセン化合物の他に、白金、パラジウム、パラジウム−クロム、ニッケル、ルテニウムを含有する化合物も使用することができる。好ましくは、Ｔｅｂｂｅ試薬またはＴｅｂｂｅ型錯体である。
本発明において、水素添加能を有する化合物（Ｄ）は、予めメタロセン系触媒（Ｃ）と接触させてから重合に使用しても良いし、別々に重合反応器に導入しても良い。各成分の使用量、使用量の比は特に制限されないが、メタロセン系触媒（Ｃ）中の遷移金属に対する水素添加能を有する化合物（Ｄ）中の金属のモル比は、０．０１〜１０００が好ましく、より好ましくは０．１〜１０である。水素添加能を有する化合物（Ｄ）の量が少ないと、分子量が向上せず、また多すぎると重合活性の低下を招く。
本発明の超高分子量エチレン系重合体は、通常の超高分子量ポリエチレンと同じ成形加工方法を用いて成形が可能である。例えば、金型に超高分子量ポリエチレン粉末を入れ、長時間加熱下圧縮成形する方法やラム押出機による押出し成形等の各種公知成形法により本発明の超高分子量エチレン系重合体の成形体を得ることができる。
また、本発明の超高分子量エチレン系重合体の成形体には、超高分子量エチレン系重合体を適当な溶剤あるいは可塑剤と混合し、フィルム状に押し出し、延伸させた後、使用した溶剤あるいは可塑剤を抽出することによって製造される微多孔質のフィルムも含まれる。このフィルムは電池用セパレータ等に使用できる。この場合、シリカ等の無機材料と混合したフィルムにすることもできる。
さらに、本発明の超高分子量エチレン系重合体粉体を適当な溶剤あるいは可塑剤に溶解あるいは混合してゲル状混合物を調製し、公知のゲル紡糸技術により超高弾性率高強度繊維を得ることもできる。
実施例１〜９及び比較例１〜４
以下、本発明を実施例、比較例を用いてさらに具体的に説明する。本発明はこれらの実施例によって一切限定されるものではない。なお、各実施例、比較例で用いた測定方法は次の通りである。
［Ｍｗ／Ｍｎの測定］
１５０−ＣＡ ＬＣ／ＧＰＣ装置（Ｗａｔｅｒｓ社製）、カラムとしてＳｈｏｄｅｘ ＡＴ−８０７Ｓ（昭和電工社製）とＴＳＫ−ｇｅｌ ＧＭＨ−Ｈ１６（東ソー社製）を直列にして用い、溶媒に１０ｐｐｍのイルガノクス１０１０を含むトリクロロベンゼンを用いて１４０℃で測定した。なお、標準物質として市販の単分散ポリスチレンを用い、検量線を作成した。
［粘度平均分子量の測定］
２０ｍｌのデカリンにポリマー２ｍｇをいれ、１５０℃、２時間攪拌してポリマーを溶解させた。その溶液を１３５℃の高温糟で、ウベローデタイプの粘度計を用いて、標線間の落下時間（ｔ_ｓ）を測定した。なお、ブランクとしてポリマーを入れていない、デカヒドロナフタレンのみの落下時間（ｔ_ｂ）を測定した。以下の式に従いポリマーの比粘度（η_ｓｐ／Ｃ）をプロットし、濃度０に外挿した極限粘度（η）を求めた。
η_ｓｐ／Ｃ ＝ （ｔ_ｓ／ｔ_ｂ−１）／０．１
この極限粘度（η）から以下の式に従い、粘度平均分子量（Ｍｖ）を求めた。
Ｍｖ＝５．３４×１０^４η^１．４９
［密度の測定］
ＡＳＴＭ Ｄ１５０５に従って測定した。試験片としては、プレスシートから切り出した切片を１２０℃で１時間アニーリングし、その後１時間かけて室温まで冷却したものを使用した。
［ＨＡＺＥの測定］
厚さ０．７ｍｍのプレスシートを作製し、２３℃±１℃で２４時間放置した試験片を用いて、ＡＳＴＭ Ｄ１００３の方法で測定した。＜測定機器（村上色彩技術研究所製、グレード名ＨＭ−１００）試料の大きさ５０ｍｍ（ｗ）＊１０ｍｍ（ｔ）＊５０ｍｍ（ｈ）、光学系ＡＳＴＭ Ｄ１００３に準拠＞
［結晶化度の測定］
示差走査型熱量計ＤＳＣ７（パーキンエルマー社製）を用い、５０℃で１分保持したのち、２００℃／分の速度で１８０℃まで昇温し、１８０℃で５分間保持したのち、１０℃／分で５０℃まで降温した。５０℃で５分間保持したのち、１０℃／分で１８０℃まで昇温し、その際に得られる融解曲線において、６０℃から１４５℃に基線を引き融解エンタルピー（Ｊ／ｇ）を求めた。これを２９３（Ｊ／ｇ）で除した値に１００を乗じた値を結晶化度（％）とした。
［末端ビニル基量の測定］
超高分子量ポリエチレンパウダーを１８０℃でプレスし、フィルムを作成した。このフィルムの赤外吸収スペクトル（ＩＲ）をＦＴ−ＩＲ５３００Ａ（日本分光社製）を用いて測定した。ビニル基は９１０ｃｍ^−１のピークの吸光度（ΔＡ）およびフィルム厚み（ｔ（ｍｍ））より次式に従い算出した。
ビニル基量（個／１０００Ｃ）＝０．９８×ΔＡ／ｔ
［残存Ｔｉ量およびＣｌ量の測定］
超高分子量エチレン系重合体パウダーを適当量採取し、硝酸を添加し分解させた。この分解物に純水を加えて測定試料を調製した。市販されている原子吸光分析用標準液を硝酸水溶液で希釈し、標準液として用いた。ＩＣＰ測定をＪＹ１３８（理学社製）を用いて測定した。
［計算値１の計算式］
計算値１は、上記粘度平均分子量Ｍｖから以下の式により求めた。
計算値１＝−９×１０^−１０×Ｍｖ＋０．９３７
［計算値２の計算式］
計算値２は、上記密度ρ（ｇ／ｃｃ）から以下の式により求めた。
計算値２＝６３０ρ−５３０  The present invention will be specifically described below. First, specific embodiments of the ultrahigh molecular weight ethylene polymer will be described.
  The ethylene homopolymer (A) in the present invention is a polymer obtained from a monomer mainly composed of ethylene, and a compound having an extremely small amount of an olefinic double bond contained as an impurity in ethylene is 0% in the polymer. .1% by weight or less may be contained.
  The ethylene copolymer (B) in the present invention contains ethylene, an α-olefin having 3 to 20 carbon atoms, a cyclic olefin having 3 to 20 carbon atoms, a formula CH₂= CHR (wherein R is an aryl group having 6 to 20 carbon atoms) and at least one selected from the group consisting of linear, branched or cyclic dienes having 4 to 20 carbon atoms. It can be produced by copolymerizing a seed olefin.
  Examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1- It is selected from the group consisting of tetradecene, 1-hexadecene, 1-octadecene, and 1-eicocene. Examples of the cyclic olefin having 3 to 20 carbon atoms include cyclopentene, cyclohexene, cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, and 2-methyl-1.4,5.8-dimethano-1. , 2,3,4,4a, 5,8,8a-octahydronaphthalene. General formula CH₂The compound represented by = CHR (wherein R is an aryl group having 6 to 20 carbon atoms) is, for example, styrene, vinylcyclohexane, etc., and is a straight chain, branched or 4 to 20 carbon atoms. Cyclic dienes are, for example, from the group consisting of 1,3-butadiene, 1,4-pentadiene, 1,5-hexadiene, 1,4-hexadiene, 1,6-octadiene, 1,7-octadiene and cyclohexadiene. To be elected.
  By copolymerizing ethylene and the olefin (comonomer), it is possible to control physical properties such as density, flexibility and transparency of the ethylene copolymer (B).
  The comonomer content in the copolymer is preferably in the range of 0.1 to 25.0% by weight, more preferably in the range of 0.1 to 20.0% by weight. When the comonomer content exceeds 25.0% by weight, the density is greatly reduced, and in the suspension polymerization method, because it dissolves in the solvent used or a bulk polymer is formed, stable continuous operation cannot be performed. . Also, in the gas phase polymerization method, the polymer is easily sticky and a bulk polymer is formed, or it adheres as a scale to the inner surface of the reactor, so that stable continuous operation cannot be performed.
  The ultra high molecular weight ethylene polymer of the present invention is produced by polymerizing ethylene or copolymerizing ethylene and a comonomer by suspension polymerization or gas phase polymerization. In the suspension polymerization method, an inert hydrocarbon can be used as a medium, and the olefin itself can also be used as a solvent.
  Specific examples of the inert hydrocarbon medium include aliphatic hydrocarbons such as propane, butane, isobutane, pentane, isopentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, and methylcyclopentane. And alicyclic hydrocarbons such as benzene, toluene, xylene and the like; halogenated hydrocarbons such as ethyl chloride, chlorobenzene and dichloromethane, and mixtures thereof.
  The polymerization temperature is usually preferably 60 ° C. or higher, more preferably 70 ° C. or higher and 150 ° C. or lower, more preferably 100 ° C. or lower. The polymerization pressure is usually preferably normal pressure to 10 MPa, more preferably 0.2 to 5 MPa, and still more preferably 0.5 to 3 MPa. The polymerization reaction can be carried out in any of batch, semi-continuous and continuous methods.
  It is also possible to carry out the polymerization in two or more stages having different reaction conditions. Furthermore, as described in, for example, West German Patent Publication No. 3127133, the molecular weight of the resulting olefin polymer is adjusted by the presence of hydrogen in the polymerization system or by changing the polymerization temperature. You can also In addition, in this invention, the other component useful for manufacture of an ultra high molecular weight ethylene polymer other than each above components can be included.
  The viscosity average molecular weight (Mv) of the ultra high molecular weight ethylene polymer of the present invention is obtained by dissolving the ultra high molecular weight ethylene polymer in decalin at different concentrations and extrapolating the solution viscosity obtained at 135 ° C. to a concentration of 0. From the obtained intrinsic viscosity (η (dl / g)), it can be obtained by the following formula.
  Mv = 5.34 × 10⁴η^1.49
  The viscosity average molecular weight of the ultrahigh molecular weight ethylene polymer of the present invention determined from this formula is usually 1 million or more, preferably 2 million or more. Ultra high molecular weight polyethylene having a viscosity average molecular weight exceeding 1,000,000 is excellent in wear resistance, low friction and strength. Therefore, sliding members such as gears, bearing members, artificial joint substitutes, ski sliding surfaces, abrasives, various magnetic tape slip sheets, flexible disk liners, bulletproof members, battery separators, various filters, foams It is also suitable as a material for applications such as film, pipe, fiber, thread, fishing line, cutting board and the like. In addition, the ultra-high molecular weight ethylene polymer of the present invention is excellent not only in low friction but also in flexibility and transparency. Sole). Further, since the strength (impact resistance and puncture strength) is higher than that of a normal ultra-high molecular weight ethylene polymer, it is also suitably used for battery separators and filters.
  The molecular weight distribution (Mw / Mn) defined as the ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the ultrahigh molecular weight ethylene polymer of the present invention can be determined by GPC measurement. For polymers in the normal molecular weight range, typically about 20 mg of polymer is dissolved in 15 ml of solvent (trichlorobenzene) and measured at 140 ° C. On the other hand, in the case of the ultra high molecular weight ethylene polymer of the present invention, since the solution viscosity was too high, about 2 mg of polymer was dissolved in 15 ml of solvent and measured. The molecular weight distribution (Mw / Mn) of the ultrahigh molecular weight ethylene polymer of the present invention determined by this method is more than 3 and 10 or less, preferably 3.8 or more and 8 or less.
  The amount of Ti and Cl remaining in the ultrahigh molecular weight ethylene polymer of the present invention can be quantified by fluorescent X-rays or ICP (ion coupling plasma). The residual amount is 3 ppm or less and 5 ppm or less, respectively, which is very small compared to the ultrahigh molecular weight ethylene polymer obtained by the Ziegler-Natta catalyst. Preferably, the residual Ti amount is 0.8 ppm or less, and the residual Cl amount is 3 ppm or less. Since the catalyst is highly active, the catalyst residue is small and a catalyst containing no Cl is used. Therefore, an ultrahigh molecular weight ethylene polymer substantially free of Cl can be obtained. As described above, the ultrahigh molecular weight ethylene polymer of the present invention containing no catalyst residue or Cl has high thermal stability, and the addition amount of an antioxidant or the like may be reduced or may not be required. .
  The crystallinity (X (%)) of the ultrahigh molecular weight ethylene polymer of the present invention was determined by DSC measurement. The sample was held at 50 ° C. for 1 minute, then heated to 180 ° C. at a rate of 200 ° C./minute, and held at 180 ° C. for 5 minutes. The temperature was further decreased to 50 ° C. at 10 ° C./min. After holding at 50 ° C. for 5 minutes, the temperature is raised to 180 ° C. at 10 ° C./min. In the melting curve obtained at that time, the baseline is drawn from 60 ° C. to 145 ° C. and the melting enthalpy (ΔH (J / g)) is Asked. The crystallinity (X (%)) of the ultrahigh molecular weight ethylene polymer of the present invention can be determined from this melting enthalpy using the following equation.
  X = ΔH × 100/293
  Further, the crystallinity (X (%)) of the ultrahigh molecular weight ethylene polymer of the present invention determined as described above and the density (ρ (g / cc)) measured according to ASTM D1505 satisfy the following relational expression.
  100X <630ρ−530
  Such low crystallinity is a characteristic of the ultrahigh molecular weight ethylene polymer of the present invention, and is a characteristic that can be clearly distinguished from known ultrahigh molecular weight ethylene polymers. The ultrahigh molecular weight ethylene polymer of the present invention has a low density without introducing a comonomer, and a flexible molded article or fiber can be obtained. Moreover, since it is not necessary to introduce a comonomer, the polymerization activity does not decrease and high activity can be maintained. On the other hand, when a large amount of comonomer is inserted, an ultrahigh molecular weight ethylene polymer excellent in transparency and flexibility can be obtained with a lower crystallinity.
  The amount of terminal vinyl groups of the ultrahigh molecular weight ethylene polymer of the present invention can be determined by measuring the infrared absorption spectrum (IR) of the ultrahigh molecular weight ethylene polymer film, and the vinyl group content is 910 cm.^-1It is calculated according to the following formula from the absorbance (ΔA) of the peak and the thickness (t (mm)) of the film.
  Amount of vinyl group (pieces / 1000 C) = 0.98 × ΔA / t
  The amount is 0.02 or less per 1000 carbons, preferably 0.005 or less. When the amount of vinyl groups is large, it becomes difficult to produce an ultrahigh molecular weight ethylene polymer. That is, when a catalyst that easily generates a terminal vinyl group is used, unless the polymerization temperature is lowered to suppress the generation of the terminal vinyl group, the ultra high molecular weight is not sufficiently achieved. In addition, the molecular weight must be controlled by a small amount of hydrogen, and stable production is difficult from the viewpoint of manufacturing operation. Further, when the polymerization is carried out at a low temperature, the activity is lowered, so the production rate is also lowered, which adversely affects the finishing process, the packaging process and the like.
  Further, the density (ρ (g / cc)) of the ultrahigh molecular weight ethylene polymer of the present invention and the viscosity average molecular weight (Mv) satisfy the following relational expression.
  ρ ≦ −9 × 10^-10× Mv + 0.937
  The density (ρ (g / cc)) of the ultrahigh molecular weight ethylene polymer of the present invention is 0.850 or more and 0.925 or less. Preferably they are 0.900 or more and 0.925 or less.
  HAZE, which is an index of transparency of the ultrahigh molecular weight ethylene polymer of the present invention, is 70% or less, preferably 65% or less when measured by the method of ASTM D1003.
  The ultrahigh molecular weight ethylene polymer of the present invention has a molecular weight distribution profile of a polymer determined by GPC / FT-IR, where Mt is the molecular weight showing the maximum peak position, and Mt is an arbitrary molecular weight, and Mc. And
  | Log (Mt) −log (Mc) | ≦ 0.5
The slope of the approximate straight line by the least square method of the comonomer concentration profile in the polymer is within the range of
  0.0005 ≦ {C (Mc¹) -C (Mc²)} / (LogMc¹-LogMc²) ≤ 0.05
(However, in the above formula, Mc¹, Mc²Indicates an arbitrary molecular weight, and C (Mc¹), C (Mc²) Is Mc¹, Mc²The comonomer density | concentration on the approximate straight line by the least squares method in is shown. )
It is in the range.
  The comonomer concentration profile can be obtained by combining gel permeation chromatography (GPC) and Fourier transform infrared absorption spectrum (FT-IR). In the present invention, GPC / FT-IR uses a 150 CA LC / GPC apparatus (manufactured by Waters), a column of Shodex AT-807S (manufactured by Showa Denko) and TSK-gel GMH-H6 (manufactured by Tosoh Corporation). Two were used in series. For FT-IR, 1760X (manufactured by PERKIN-ELMER) was used, and 2 mg to 10 mg of a sample was dissolved in 15 ml of trichlorobenzene at a temperature of 140 ° C., and 500 μl to 1000 μl were injected and measured.
  In the present invention, the comonomer concentration is defined as a value obtained by dividing the number of comonomer per 1000 methylene groups contained in the ultrahigh molecular weight ethylene polymer by the number of methylene groups. That is, when the number of comonomers per 1000 methylene groups is 5, the comonomer concentration is 0.005. Such a comonomer concentration is specifically determined from the ratio of the absorption intensity related to the comonomer determined by FT-IR and the absorption intensity of the methylene group. For example, when the comonomer is a linear α-olefin, the comonomer concentration is 2960 cm.^-1The absorption strength of methyl group and 2925 cm^-1It is calculated | required from ratio of the absorption intensity of a methylene group.
  Generally, the comonomer concentration profile obtained by the GPC / FT-IR measurement is displayed as an accumulation of points indicating the comonomer concentration. In order to increase the accuracy of measurement of the comonomer concentration profile, it is desirable to measure the same sample several times under the same conditions and increase the number of comonomer concentration measurement points as much as possible. In the present invention, an approximate straight line of the comonomer concentration profile is obtained by drawing an approximate straight line within the above range based on the measurement points thus obtained.
  In the present invention, the slope of the approximate straight line of the comonomer concentration profile is defined by the following equation.
  {C (Mc¹) -C (Mc²)} / (LogMc¹-LogMc²)
(However, in the above formula, Mc¹, Mc²Indicates an arbitrary molecular weight, and C (Mc¹), C (Mc²) Is Mc¹, Mc²The comonomer concentration on the approximate straight line at is shown. )
  The comonomer concentration profile represents the change in comonomer concentration with respect to the molecular weight, and the slope of the approximate line of the profile represents the degree of change in comonomer concentration with respect to the change in molecular weight.
  Conventionally, in an ethylene polymer obtained from a commonly used Ziegler-Natta catalyst, only a negative slope of the approximate straight line has been obtained. That is, the comonomer content decreased with increasing molecular weight. In addition, when a comonomer was introduced, it was difficult to increase the molecular weight, and there was almost no thing in the ultra-high molecular weight region. Even in ethylene polymers having a normal molecular weight range using metallocene catalysts that have been put into practical use in recent years, the value of the slope of the approximate straight line of the above-mentioned comonomer concentration profile is almost zero. Was 0.0001 or less.
  In contrast, the ultrahigh molecular weight ethylene polymer of the present invention exhibits a slope of an approximate straight line of the comonomer concentration profile of 0.0005 or more in the above range. Therefore, the ultra-high molecular weight ethylene polymer of the present invention has a remarkable tendency that the high molecular weight component has a higher comonomer content than the low molecular weight component, and has higher impact resistance and environmental stress resistance than conventional products. Excellent physical properties.
  More preferably, the ultra high molecular weight ethylene polymer of the present invention is
  | Log (Mt) −log (Mc) | ≦ 0.5
(However, Mt and Mc are as defined above.)
The slope of the approximate straight line by the least square method of the comonomer concentration profile in the polymer is within the range of
  0.001 ≦ {C (Mc¹) -C (Mc²)} / (LogMc¹-LogMc²) ≦ 0.02
(However, C (Mc¹), C (Mc²), Mc¹, Mc²Is as defined above. )
It is in the range.
  When the ultra high molecular weight ethylene polymer of the present invention is subjected to cross fractionation chromatography (cross fraction chromatography; CFC) measurement, the maximum extraction amount is obtained at each extraction temperature of the ultra high molecular weight ethylene polymer. In the temperature range not lower than the extraction temperature (first temperature) and not higher than the temperature (second temperature) 10 ° C. above, the arbitrary extraction temperature T (° C.) in the CFC and the components extracted at the arbitrary extraction temperature ( When the relationship between the molecular weight Mp (T), which is one point represented by the molecular weight on the molecular weight distribution profile of the polymer fraction) and shows the maximum intensity peak, is linearly approximated by the least square method, The inclination of the approximate line satisfies the following relational expression.
  −1 ≦ {logMp (T¹) -LogMp (T²)} / (T¹-T²) ≦ −0.005
(Where T¹And T²Are two different arbitrary extraction temperatures T (° C.) in the range between the first temperature and the second temperature, and Mp (T¹) And Mp (T²) Are T on the approximate straight line, respectively.¹And T²The molecular weight corresponding to )
  In the above formula,
  {LogMp (T¹) -LogMp (T²)} / (T¹-T²)
Is the slope of a straight line when the relationship between the extraction temperature T (° C.) in CFC and the molecular weight Mp (T) of the maximum peak position of the molecular weight distribution of the polymer component extracted at the extraction temperature is approximated by the least square method Is shown.
  CFC in the present invention was measured with CFC T-150A (Mitsubishi Chemical). The sample is measured by dissolving 2 to 10 mg in 20 ml of dichlorobenzene at 140 ° C. 5 ml of the sample is injected into a TREF (Temperature Rising Elution Fractionation) column packed with glass beads, and the temperature is lowered from 140 ° C. at 1 ° C./min. Further, the column is heated up to 140 ° C. at 1 ° C./min to extract the polymer component. The extracted polymer component is guided to a GPC column (Shodex AD806MS (manufactured by Showa Denko KK)) and detected by FT-IR (Nicolet Magna-IR Spectrometer 550).
  Conventionally, in an ethylene-based polymer obtained by a commonly used Ziegler-Natta catalyst, the slope of the approximate straight line defined in the present invention is usually almost 0 or a positive value. In addition, even in an ethylene polymer using a metallocene catalyst that has been put into practical use in recent years, the value of the slope was almost close to zero. On the other hand, as in the present invention, in the CFC measurement of an ultra-high molecular weight ethylene polymer, the slope of the straight line shows a negative value when the relation of the molecular weight of the maximum peak position to the extraction temperature is linearly approximated by the least square method. This indicates that a component having a lower extraction temperature, that is, a low-density component having a higher comonomer content has a higher molecular weight. In the ultra high molecular weight ethylene polymer of the present invention, the inclination is smaller than −0.005 and shows a considerably large negative inclination. Therefore, the high molecular weight component-containing component tends to have a higher molecular weight than the conventional product. I can ask.
  Moreover, since the ultrahigh molecular weight ethylene polymer of the present invention exhibits a negative slope over a wide continuous extraction temperature range, the low comonomer concentration low molecular weight component, that is, from the high density low molecular weight component to the high comonomer concentration high molecular weight. It also shows that the composition changes continuously over a wide range to components, ie low density high molecular weight components.
  In the CFC measurement of the ultrahigh molecular weight ethylene polymer of the present invention, the preferred range of the slope of the straight line when the relation of the molecular weight of the maximum peak position to the extraction temperature is linearly approximated by the least square method is:
−0.1 ≦ {logMp (T¹) -LogMp (T²)} / (T¹-T²) ≦ −0.01
(Mp (T¹), Mp (T²), T¹, T²Is as defined above. )
And a more preferable range is
  −0.08 ≦ {logMp (T¹) -LogMp (T²)} / (T¹-T²) ≦ −0.02
It is.
  The ultra high molecular weight ethylene polymer of the present invention has a temperature of 10 ° C. or lower than the extraction temperature at which the maximum extraction amount is obtained at each extraction temperature of the ultra high molecular weight ethylene polymer when CFC measurement is performed. The total amount of the components extracted in is 8% by weight or less. In the present invention, the amount of the extracted component is obtained from an integral curve with respect to the extraction temperature of the extracted component obtained by the CFC measurement.
  When an ethylene polymer obtained using a conventional Ziegler-Natta catalyst is subjected to CFC measurement, components can be extracted over a wide temperature range below the extraction temperature at which the maximum extraction amount is obtained. This indicates that the composition distribution of the ethylene polymer obtained by the Ziegler-Natta catalyst is wide and includes a low molecular weight wax component that can be extracted at a low temperature and an extremely low density component. An ethylene polymer obtained by a metallocene catalyst that has been put into practical use in recent years is generally considered to have a narrow composition distribution. However, according to CFC measurement, a large amount of low-temperature extraction components are detected over a wide temperature range.
  The ultra high molecular weight ethylene polymer of the present invention has extremely few such low temperature extraction components. Specifically, when the CFC measurement of the ultrahigh molecular weight ethylene polymer of the present invention is performed, the total amount of components extracted at a temperature not higher than 10 ° C. below the extraction temperature at which the maximum extraction amount is obtained is 8 wt. % Or less, more preferably 5% by weight or less, and still more preferably 3.5% by weight or less. Since the ultrahigh molecular weight ethylene polymer of the present invention has very few low-temperature extraction components as described above, there is no adverse effect on physical properties due to the presence of the wax component and the low-density component, and the quality is essentially high.
  Next, a method for producing the ultrahigh molecular weight ethylene polymer in the present invention will be described.
  The metallocene catalyst (C) used in the present invention can form at least a) a transition metal compound having a cyclic η-bonding anion ligand and b) a complex that reacts with the transition metal compound and exhibits catalytic activity. It consists of two catalyst components of an activator.
  The transition metal compound having a cyclic η-bonding anion ligand used in the present invention can be represented, for example, by the following general formula (1).

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anionic ligand, and the ligand optionally has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, carbon A halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, and a hydrocarbyl phosphine having 1 to 12 carbon atoms 1 to 20 non-chosen selected from the group consisting of a fino group, a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group Is a substituent having an atom,
  M is a transition metal selected from the group of transition metals belonging to Group 4 of the periodic table having a formal oxidation number of +2, +3, or +4, and at least one ligand L has η⁵Represents a transition metal bonded,
  W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and M at a valence of 1 each, thereby synergizing with L and M to form a metalla. Represents a divalent substituent that forms a cycle;
  X is each independently a monovalent anionic σ-bonded ligand, a divalent anionic σ-bonded ligand that binds to M bivalently, and L and M each monovalently An anionic σ-bonded ligand having 1 to 60 non-hydrogen atoms, selected from the group consisting of divalent anionic σ-bonded ligands bonded by a valence;
  X ′ each independently represents a neutral Lewis base coordination compound having 1 to 40 non-hydrogen atoms;
  j is 1 or 2, provided that when j is 2, in some cases, two ligands L are bonded to each other through a divalent group having 1 to 20 non-hydrogen atoms, The divalent group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, and a hydrocarbyleneamino group having 1 to 12 carbon atoms. A group selected from the group consisting of a group, a silanediyl group, a halosilanediyl group, and a silyleneamino group,
  k is 0 or 1,
  p is 0, 1 or 2, provided that X is a monovalent anionic σ-bonded ligand or a divalent anionic σ-bonded ligand bonded to L and M , P is an integer 1 or more smaller than the formal oxidation number of M, and when X is a divalent anionic σ-bonded ligand bonded only to M, p is smaller than the formal oxidation number of M ( j + 1) an integer smaller than or equal to
  q is 0, 1 or 2. )
  Examples of the ligand X in the compound of the above formula (1) include a halide, a hydrocarbon group having 1 to 60 carbon atoms, a hydrocarbyloxy group having 1 to 60 carbon atoms, a hydrocarbylamide group having 1 to 60 carbon atoms, Examples thereof include hydrocarbyl phosphide groups having 1 to 60 carbon atoms, hydrocarbyl sulfide groups having 1 to 60 carbon atoms, silyl groups, and composite groups thereof.
  Examples of the neutral Lewis base coordination compound X ′ in the compound of the above formula (1) include phosphine, ether, amine, olefin having 2 to 40 carbon atoms, diene having 1 to 40 carbon atoms, and these compounds. Examples thereof include a derived divalent group.
  In the present invention, the transition metal compound having a cyclic η-bonding anion ligand is preferably a transition metal compound represented by the formula (1) (where j = 1).
  Preferable examples of the compound represented by the formula (1) (where j = 1) include compounds represented by the following formula (3).

  (Wherein, M represents a transition metal selected from the group consisting of titanium, zirconium and hafnium, and represents a transition metal having a formal oxidation number of +2, +3 or +4,
  R⁵Are each independently selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 8 carbon atoms, a silyl group, a germyl group, a cyano group, a halogen atom, and a composite group thereof. Represents a substituent having an atom, provided that the substituent R⁵Is a hydrocarbon group having 1 to 8 carbon atoms, a silyl group or a germyl group, in some cases, two adjacent substituents R⁵Are bonded to each other to form a divalent group, whereby the two adjacent substituents R⁵To form a ring by cooperating with the bond between two carbon atoms of the cyclopentadienyl ring that is bonded to each of
  X ″ each independently represents a halide, a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbyloxy group having 1 to 18 carbon atoms, a hydrocarbylamino group having 1 to 18 carbon atoms, a silyl group, or a group having 1 to 18 carbon atoms. Represents a substituent having 1 to 20 non-hydrogen atoms selected from the group consisting of a hydrocarbyl amide group, a hydrocarbyl phosphide group having 1 to 18 carbon atoms, a hydrocarbyl sulfide group having 1 to 18 carbon atoms and a composite group thereof. However, in some cases, two substituents X ″ may cooperate to form a neutral conjugated diene having 4 to 30 carbon atoms or a divalent group,
  Y 'is -O-, -S-, -NR^*-Or -PR^*-, Where R^*Is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 8 carbon atoms, a silyl group, a halogenated alkyl group having 1 to 8 carbon atoms, a halogenated aryl group having 6 to 20 carbon atoms, Or these complex groups,
  Z is SiR^* ₂, CR^* ₂, SiR^* ₂SiR^* ₂, CR^* ₂CR^* ₂, CR^*= CR^*, CR^* ₂SiR^* ₂Or GeR^* ₂Where R is^*Is as defined above,
  n is 1, 2 or 3. )
  Specific examples of the transition metal compound having a cyclic η-bonding anion ligand used in the present invention include the following compounds.
  Bis (methylcyclopentadienyl) zirconium dimethyl, bis (n-butylcyclopentadienyl) zirconium dimethyl, bis (indenyl) zirconium dimethyl, bis (1,3-dimethylcyclopentadienyl) zirconium dimethyl,
  (Pentamethylcyclopentadienyl) (cyclopentadienyl) zirconium dimethyl, bis (cyclopentadienyl) zirconium dimethyl, bis (pentamethylcyclopentadienyl) zirconium dimethyl,
  Bis (fluorenyl) zirconium dimethyl, ethylenebis (indenyl) zirconium dimethyl, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) zirconium dimethyl, ethylenebis (4-methyl-1-indenyl) zirconium dimethyl, ethylene Bis (5-methyl-1-indenyl) zirconium dimethyl,
  Ethylene bis (6-methyl-1-indenyl) zirconium dimethyl, ethylene bis (7-methyl-1-indenyl) zirconium dimethyl, ethylene bis (5-methoxy-1-indenyl) zirconium dimethyl, ethylene bis (2,3-dimethyl) -1-indenyl) zirconium dimethyl, ethylenebis (4,7-dimethyl-1-indenyl) zirconium dimethyl, ethylenebis- (4,7-dimethoxy-1-indenyl) zirconium dimethyl, methylenebis (cyclopentadienyl) zirconium dimethyl ,
  Isopropylidene (cyclopentadienyl) zirconium dimethyl, isopropylidene (cyclopentadienyl-fluorenyl) zirconium dimethyl,
  Silylene bis (cyclopentadienyl) zirconium dimethyl, dimethylsilylene (cyclopentadienyl) zirconium dimethyl, [(Nt-butyramide) (tetramethyl-η⁵-Cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl, [(Nt-butyramide) (tetramethyl-η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl,
  [(N-methylamide) (tetramethyl-η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl, [(N-phenylamide) (tetramethyl-η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl, [(N-benzylamide) (tetramethyl-η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl, [(Nt-butyramide) (η⁵-Cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl,
  [(Nt-butylamide) (η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl, [(N-methylamide) (η⁵-Cyclopentadienyl) -1,2-ethanediyl] titanium dimethyl, [(N-methylamide) (η⁵-Cyclopentadienyl) dimethylsilane] titanium dimethyl, [(Nt-butyramide) (η⁵-Indenyl) dimethylsilane] titanium dimethyl, [(N-benzylamide) (η⁵-Indenyl) dimethylsilane] titanium dimethyl,
  Dibromobistriphenylphosphine nickel, dichlorobistriphenylphosphine nickel, dibromodiacetonitrile nickel, dibromodibenzonitrile nickel, dibromo (1,2-bisdiphenylphosphinoethane) nickel, dibromo (1,3-bisdiphenylphosphinopropane) nickel, Dibromo (1,1′-diphenylbisphosphinoferrocene) nickel, dimethylbisdiphenylphosphinenickel, dimethyl (1,2-bisdiphenylphosphinoethane) nickel, methyl (1,2-bisdiphenylphosphinoethane) nickeltetrafluoro Borate, (2-diphenylphosphino-1-phenylethyleneoxy) phenylpyridine nickel, dichlorobistriphenylphosphine palladium, dichlorodibe Zone nitrile palladium, dichloro-di acetonitrile palladium, dichloro (1,2-bis-diphenylphosphino ethane) palladium, bis (triphenylphosphine) palladium bistetrafluoroborate, bis (2,2'-bipyridine) methyl iron tetrafluoroborate etherate, and the like.
  Specific examples of the transition metal compound having a cyclic η-bonding anion ligand used in the present invention include “dimethyl” in the names of the zirconium and titanium compounds listed above (this is the The last part of the name, that is, the part appearing immediately after the part of “zirconium” or “titanium” and corresponding to the part of X ″ in the formula (3)) is any of the following The compound which has a name made in place of a thing is also mentioned.
  “Dichloro”, “Dibromo”, “Diiodo”, “Diethyl”, “Dibutyl”, “Diphenyl”, “Dibenzyl”, “2- (N, N-dimethylamino) benzyl”, “2-butene-1,4” -Diyl "," s-Trans-η⁴-1,4-diphenyl-1,3-butadiene "," s-trans-η⁴-3-methyl-1,3-pentadiene "," s-trans-η⁴-1,4-dibenzyl-1,3-butadiene ”,“ s-trans-η⁴-2,4-hexadiene "," s-trans-η⁴-1,3-pentadiene "," s-trans-η⁴-1,4-ditolyl-1,3-butadiene ”,“ s-trans-η⁴-1,4-bis (trimethylsilyl) -1,3-butadiene ",
  “S-cis-η⁴-1,4-diphenyl-1,3-butadiene "," s-cis-η⁴-3-methyl-1,3-pentadiene "," s-cis-η⁴-1,4-dibenzyl-1,3-butadiene "," s-cis-η⁴-2,4-hexadiene "," s-cis-η⁴-1,3-pentadiene "," s-cis-η⁴-1,4-ditolyl-1,3-butadiene "," s-cis-η⁴-1,4-bis (trimethylsilyl) -1,3-butadiene "and the like.
  The transition metal compound having a cyclic η-bonding anion ligand used in the present invention can be generally synthesized by a known method. These transition metal compounds may be used alone or in combination.
  Next, an activator capable of reacting with the transition metal compound used in the present invention to form a complex exhibiting catalytic activity (hereinafter sometimes simply referred to as “activator” in the present invention) will be described.
  Examples of the activator in the present invention include compounds defined by the following general formula (2).

(Where [L-H]^{d +}Represents a proton-donating Bronsted acid, wherein L represents a neutral Lewis base, d is an integer from 1 to 7;_mQ_p]^d-Represents a compatible non-coordinating anion, where M represents a metal or metalloid belonging to any one of Groups 5 to 15 of the periodic table, and Q each independently represents hydride, halide, carbon. Selected from the group consisting of a dihydrocarbylamide group having 2 to 20 carbon atoms, a hydrocarbyloxy group having 1 to 30 carbon atoms, a hydrocarbon group having 1 to 30 carbon atoms, and a substituted hydrocarbon group having 1 to 40 carbon atoms, However, among the Qs independently selected in the formula (2), the number of Q as a halide is 0 or 1, m is an integer of 1 to 7, and p is an integer of 2 to 14. , D are as defined above, and pm = d. )
  Specific examples of the non-coordinating anion include, for example, tetrakisphenyl borate, tri (p-tolyl) (phenyl) borate, tris (pentafluorophenyl) (phenyl) borate, tris (2,4-dimethylphenyl) (hydrphenyl) ) Borate, tris (3,5-dimethylphenyl) (phenyl) borate, tris (3,5-di-trifluoromethylphenyl) (phenyl) borate, tris (pentafluorophenyl) (cyclohexyl) borate, tris (pentafluoro) Phenyl) (naphthyl) borate, tetrakis (pentafluorophenyl) borate, triphenyl (hydroxyphenyl) borate, diphenyl-di (hydroxyphenyl) borate, triphenyl (2,4-dihydroxyphenyl) borate, tri (p-to) Ru) (hydroxyphenyl) borate, tris (pentafluorophenyl) (hydroxyphenyl) borate, tris (2,4-dimethylphenyl) (hydroxyphenyl) borate, tris (3,5-dimethylphenyl) (hydroxyphenyl) borate, Tris (3,5-di-trifluoromethylphenyl) (hydroxyphenyl) borate, Tris (pentafluorophenyl) (2-hydroxyethyl) borate, Tris (pentafluorophenyl) (4-hydroxybutyl) borate, Tris (penta Fluorophenyl) (4-hydroxy-cyclohexyl) borate, tris (pentafluorophenyl) (4- (4′-hydroxyphenyl) phenyl) borate, tris (pentafluorophenyl) (6-hydroxy-2-naphtho) Le) borate, and the like.
  Examples of other preferable non-coordinating anions include borates in which the hydroxy group of the borate exemplified above is replaced with an NHR group. Here, R is preferably a methyl group, an ethyl group or a tert-butyl group.
  Specific examples of proton-providing Bronsted acids include triethylammonium, tripropylammonium, tri (n-butyl) ammonium, trimethylammonium, tributylammonium, tri (n-octyl) ammonium and the like. And alkyl group-substituted ammonium cations. N, N-dimethylanilinium, N, N-diethylanilinium, N, N-2,4,6-pentamethylanilinium, N, N-dimethylbenzylanily Also suitable are N, N-dialkylanilinium cations such as nium.
  Furthermore, dialkylammonium cations such as di- (i-propyl) ammonium, dicyclohexylammonium and the like are also suitable, and triaryls such as triphenylphosphonium, tri (methylphenyl) phosphonium, tri (dimethylphenyl) phosphonium and the like. Also suitable are phosphonium cations, dimethylsulfonium, diethylfuronium, diphenylsulfonium and the like.
  In the present invention, an organometallic oxy compound having a unit represented by the following formula (4) can also be used as an activator.

(However, M²Is a metal or metalloid of Groups 13 to 15 of the Periodic Table, R is each independently a hydrocarbon group or substituted hydrocarbon group having 1 to 12 carbon atoms, and n is a metal M²And m is an integer of 2 or more. )
  A preferred example of the activator of the present invention is an organoaluminum oxy compound containing a unit represented by the following formula (5), for example.

(However, R is an alkyl group having 1 to 8 carbon atoms, and m is an integer of 2 to 60.)
  A further preferred example of the activator of the present invention is methylalumoxane containing a unit represented by the following formula (6), for example.

(However, m is an integer of 2-60.)
  In the present invention, the activator components may be used alone or in combination.
  In the present invention, these catalyst components can be supported on a solid component and used as a supported catalyst. Examples of such a solid component include porous polymer materials such as polyethylene, polypropylene, and copolymers of styrene divinylbenzene, or silica, alumina, magnesia, magnesium chloride, zirconia, titania, boron oxide, calcium oxide, zinc oxide, and the like. Selected from inorganic solid materials of group 2, 3, 4, 13 and 14 elements of the periodic table such as barium oxide, vanadium pentoxide, chromium oxide and thorium oxide, and mixtures thereof, and complex oxides thereof At least one inorganic solid material.
  Examples of the composite oxide of silica include composite oxides of silica such as silica magnesia, silica alumina and the like and elements of Group 2 or Group 13 of the periodic table. In addition to the above two catalyst components, an organoaluminum compound can be used as a catalyst component as required. The organoaluminum compound that can be used in the present invention is, for example, a compound represented by the following formula (7).

(However, R is an alkyl group having 1 to 12 carbon atoms and an aryl group having 6 to 20 carbon atoms, X is a halogen, hydrogen or alkoxyl group, and the alkyl group is linear, branched or cyclic. , N is an integer from 1 to 3.)
  The organoaluminum compound of the present invention may be a mixture of compounds represented by the general formula (7). For example, R in the above general formula includes a methyl group, an ethyl group, a butyl group, an isobutyl group, a hexyl group, an octyl group, a decyl group, a phenyl group, a tolyl group and the like, and X is a methoxy group, an ethoxy group , Butoxy group, chloro and the like.
  Specific examples of the organoaluminum compound used in the present invention include trimethylaluminum, triethylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, etc., or these organoaluminum and methyl alcohol, ethyl Reaction products with alcohols such as alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, octyl alcohol, and decyl alcohol, such as dimethylmethoxyaluminum, diethylethoxyaluminum, and dibutylbutoxyaluminum.
  Next, the hydrogenating agent used in the present invention will be described.
  Examples of hydrogenating agents include hydrogen and R_rn(Mt)_αH_n(In the formula, Mt is an atom belonging to Groups 1 to 3, 14 and 15 of the periodic table, and R is an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, and the number of carbon atoms. A hydrocarbon group selected from the group consisting of an alkylaryl group having 7 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, and an alkenyl group having 2 to 20 carbon atoms, and n> 0, rn ≧ 0, r is the valence of Mt).
  Of these, preferred are hydrogen or R_nSiH_4-n(In the formula, 0 ≦ n ≦ 1, R is an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, or 7 to 20 carbon atoms. A hydrocarbon group selected from the group consisting of an arylalkyl group and an alkenyl group having 2 to 20 carbon atoms.), And hydrogen is particularly preferred.
  Specific examples of the hydrogenating agent include, for example, hydrogen, sodium hydride, calcium hydride, lithium aluminum hydride, SiH₄, Methylsilane, ethylsilane, n-butylsilane, octylsilane, octadecylsilane, phenylsilane, benzylsilane, dimethylsilane, diethylsilane, di-n-butylsilane, dioctylsilane, dioctadecylsilane, diphenylsilane, dibenzylsilane, ethenylsilane, 3- Examples include butenyl silane, 5-hexenyl silane, cyclohexenyl silane, 7-octenyl silane, 17-octadecenyl silane, and the like, preferably hydrogen, octyl silane, or phenyl silane.
  In the present invention, these hydrogenating agents may be used alone or in combination.
  The metallocene catalyst (C) is used in the polymerization after contacting with a hydrogenating agent in advance. Examples of the method of bringing the metallocene catalyst into contact with the hydrogenating agent before introducing the metallocene catalyst into the polymerization reactor include, for example, 1) adding a hydrogenating agent to the catalyst transfer medium and transferring the catalyst to the polymerization reactor during transfer to the polymerization reactor. Examples include a method of bringing a hydrogenating agent into contact, and 2) a step before transferring the catalyst, for example, a method in which a hydrogenating agent is introduced into a catalyst storage tank and the catalyst is brought into contact with the hydrogenating agent.
  As the method of 1) above, for example, by connecting a supply line of a hydrogenating agent to a catalyst transfer line provided for introducing a catalyst into the polymerization reactor, and supplying the hydrogenating agent to the line, The medium can contain a hydrogenating agent. Alternatively, a hydrogenation agent supply line is connected to a catalyst supply nozzle provided inside the polymerization reactor for introducing the catalyst into the polymerization reactor, and hydrogenation agent is supplied to the line to supply hydrogen to the medium. An agent can be included. Alternatively, a hydrogenating agent may be previously contained in a medium for transferring the catalyst to the polymerization reactor, and the catalyst may be transferred to the polymerization reactor using the hydrogenating agent-containing catalyst transfer medium.
  In the case of the above method 2), the contact time is not particularly limited, but is preferably within 10 minutes, more preferably within 5 minutes, further preferably within 1 minute, still more preferably within 30 seconds, most preferably Preferably, it is within 20 seconds.
  In the present invention, the amount of the hydrogenating agent to be brought into contact with the metallocene catalyst is 0.5 to 5 000 mol of the transition metal compound contained in the catalyst. When the amount of the hydrogenating agent is less than 0.5 times mol, a massive polymer is produced and stable operation becomes difficult. On the other hand, if the amount of the hydrogenating agent is more than 50000 times mol, the polymerization activity and the molecular weight are reduced. The amount of the hydrogenating agent is preferably 1-fold mol and 30000-fold mol or less, more preferably 10-fold mol and 1000-fold mol or less.
  Next, the compound (D) having a hydrogenation ability used in the present invention will be described. The compound having hydrogenation ability is a compound that can react with hydrogen and hydrogenate ethylene or α-olefin in the system, and consequently reduce the hydrogen concentration in the polymerization reaction reactor. Any compound that does not decrease the catalytic activity may be used. A metallocene compound or a compound containing platinum, palladium, palladium-chromium, nickel, or ruthenium can be used. Among them, a metallocene compound having a high hydrogenation activity is preferable, and a titanocene compound or a half titanocene compound that can exhibit a hydrogenation activity near the polymerization temperature is particularly preferable.
  These titanocene compounds or half-titanocene compounds are capable of hydrogenation activity alone, but are preferred because they can be mixed and reacted with organometallic compounds such as organolithium, organomagnesium, and organoaluminum to increase the hydrogenation activity.
  The mixing and reaction of the organometallic compound with the titanocene compound or the half titanocene compound may be performed before feeding into the polymerization reactor, or may be performed separately in the polymerization reactor and performed in the polymerization reactor system. .
  The titanocene compound or the half titanocene compound used in the present invention can be represented, for example, by the following general formula (8).

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anionic ligand, and the ligand optionally has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, carbon A halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, and a hydrocarbyl phosphine having 1 to 12 carbon atoms 1 to 20 non-chosen selected from the group consisting of a fino group, a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group Is a substituent having an atom,
  Ti has a formal oxidation number of +2, +3 or +4, and at least one ligand L has η⁵Represents bonded titanium,
  W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and Ti at a valence of 1 each, thereby cooperating with L and Ti to form a metallacycle. Represents a divalent substituent that forms
  X and X ′ are each independently a monovalent ligand, a divalent ligand that binds divalently to Ti, and a divalent bond that binds to L and Ti each with a monovalent valence. A ligand selected from the group consisting of: a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Aminohydrocarbyl group, hydrocarbyloxy group having 1 to 12 carbon atoms, dihydrocarbylamino group having 1 to 12 carbon atoms, hydrocarbylphosphino group having 1 to 12 carbon atoms, silyl group, aminosilyl group, hydrocarbyl having 1 to 12 carbon atoms Represents a ligand having 1 to 20 non-hydrogen atoms selected from the group consisting of an oxysilyl group and a halosilyl group;
  j is 1 or 2, provided that when j is 2, in some cases, two ligands L are bonded to each other through a divalent group having 1 to 20 non-hydrogen atoms, The divalent group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, and a hydrocarbyleneamino group having 1 to 12 carbon atoms. A group selected from the group consisting of a group, a silanediyl group, a halosilanediyl group, and a silyleneamino group,
  k is 0 or 1,
  p is 0, 1 or 2, provided that when X is a monovalent ligand or a divalent ligand bonded to L and Ti, p is 1 from the formal oxidation number of Ti. When X is a divalent anionic σ-bonded ligand bonded only to Ti, p is an integer smaller than (j + 1) or more than the formal oxidation number of Ti,
  q is 0, 1 or 2. )
  Specific examples of the titanocene compound used in the present invention include the following compounds when the cyclic η-bonding anion ligand is a cyclopentadienyl group.
  Bis (cyclopentadienyl) titanium dimethyl, bis (cyclopentadienyl) titanium diethyl, bis (cyclopentadienyl) titanium diisopropyl, bis (cyclopentadienyl) titanium di-n-butyl, bis (cyclopentadienyl) ) Titanium di-sec-butyl, bis (cyclopentadienyl) titanium dihexyl, bis (cyclopentadienyl) titanium dioctyl, bis (cyclopentadienyl) titanium dimethoxide, bis (cyclopentadienyl) titanium diethoxide Bis (cyclopentadienyl) titanium diisopropoxide, bis (cyclopentadienyl) titanium dibutoxide, bis (cyclopentadienyl) titanium diphenyl, bis (cyclopentadienyl) titanium di m-tolyl, bis (cyclopentadienyl) titanium di-p-tolyl, bis (cyclopentadienyl) titanium di-m, p-xylyl, bis (cyclopentadienyl) titanium di-4-ethylphenyl, bis (Cyclopentadienyl) titanium di-4-hexylphenyl, bis (cyclopentadienyl) titanium di-4-methoxyphenyl, bis (cyclopentadienyl) titanium di-4-ethoxyphenyl, bis (cyclopentadienyl) ) Titanium diphenoxide, bis (cyclopentadienyl) titanium difluoride, bis (cyclopentadienyl) titanium dibromide, bis (cyclopentadienyl) titanium dichloride, bis (cyclopentadienyl) titanium dibromide, bis (Cyclopentadi Nyl) titanium diiodide, bis (cyclopentadienyl) titanium chloride methyl, bis (cyclopentadienyl) titanium chloride ethoxide, bis (cyclopentadienyl) titanium chloride phenoxide, bis (cyclopentadienyl) titanium di Benzyl, bis (cyclopentadienyl) titanium di-dimethylamide, bis (cyclopentadienyl) titanium di-diethylamide, bis (cyclopentadienyl) titanium di-diisopropylamide, bis (cyclopentadienyl) titanium di- Di-sec-butylamide, bis (cyclopentadienyl) titanium di-di-tert-butyramide, bis (cyclopentadienyl) titanium di-ditrimethylsilylamide, and the like.
  As specific examples of the titanocene compound used in the present invention, a compound having a name formed by replacing the above-mentioned “cyclopentadienyl” part with any cyclic η-bonding anion ligand listed below Also mentioned.
  “Methylcyclopentadienyl”, “n-butylcyclopentadienyl”, “1,3-dimethylcyclopentadienyl”, “pentamethylcyclopentadienyl”, “tetramethylcyclopentadienyl”, “trimethylsilyl” “Cyclopentadienyl”, “1,3-bistrimethylsilylcyclopentadienyl”, “indenyl”, “4,5,6,7-tetrahydro-1-indenyl”, “5-methyl-1-indenyl”, “ 6-methyl-1-indenyl, 7-methyl-1-indenyl, 5-methoxy-1-indenyl, 2,3-dimethyl-1-indenyl, 4,7-dimethyl-1- Indenyl "," 4,7-dimethoxy-1-indenyl "," fluorenyl "and the like.
  Furthermore, the two cyclic η-bonding anionic ligands constituting the titanocene compound can be arbitrarily combined from the ligands shown above. Specific examples of arbitrary combinations include (pentamethylcyclopentadienyl) (cyclopentadienyl) titanium dichloride, (fluorenyl) (cyclopentadienyl) titanium dichloride, and (fluorenyl) (pentamethylcyclopentadienyl) titanium. Dichloride, (indenyl) (cyclopentadienyl) titanium dichloride, (indenyl) (pentamethylcyclopentadienyl) titanium dichloride, (indenyl) (fluorenyl) titanium dichloride, (tetrahydroindenyl) (cyclopentadienyl) titanium dichloride , (Tetrahydroindenyl) (pentamethylcyclopentadienyl) titanium dichloride, (tetrahydroindenyl) (fluorenyl) titanium dichloride Id, (cyclopentadienyl) (1,3-bistrimethylsilylcyclopentadienyl) titanium dichloride, (pentamethylcyclopentadienyl) (1,3-bistrimethylsilylcyclopentadienyl) titanium dichloride, (fluorenyl) ( 1,3-bistrimethylsilylcyclopentadienyl) titanium dichloride, (indenyl) (1,3-bistrimethylsilylcyclopentadienyl) titanium dichloride, (tetrahydroindenyl) (1,3-bistrimethylsilylcyclopentadienyl) titanium A dichloride etc. are mentioned. In addition, compounds having names obtained by replacing the “dichloride” portion of these compounds with any of those listed below are also included.
  "Dibromide", "Diiodide", "Methyl chloride", "Methyl bromide", "Dimethyl", "Diethyl", "Dibutyl", "Diphenyl", "Dibenzyl", "Dimethoxy", "Methoxy chloride", "Bis -2- (N, N-dimethylamino) benzyl ”,“ 2-butene-1,4-diyl ”,“ s-trans-η ”⁴-1,4-diphenyl-1,3-butadiene "," s-trans-η⁴-3-methyl-1,3-pentadiene "," s-trans-η⁴-1,4-dibenzyl-1,3-butadiene ”,“ s-trans-η⁴-2,4-hexadiene "," s-trans-η⁴-1,3-pentadiene "," s-trans-η⁴-1,4-ditolyl-1,3-butadiene ”,“ s-trans-η⁴-1,4-bis (trimethylsilyl) -1,3-butadiene "," s-cis-η⁴-1,4-diphenyl-1,3-butadiene "," s-cis-η⁴-3-methyl-1,3-pentadiene "," s-cis-η⁴-1,4-dibenzyl-1,3-butadiene "," s-cis-η⁴-2,4-hexadiene "," s-dis-η⁴-1,3-pentadiene "," s-cis-η⁴-1,4-ditolyl-1,3-butadiene "," s-cis-η⁴-1,4-bis (trimethylsilyl) -1,3-butadiene "and the like.
  The two cyclic η-bonding anion ligands may be bonded via the following groups.
  -SiR^* ₂-, -CR^* ₂-, -SiR^* ₂SiR^* ₂-, -CR^* ₂CR^* ₂-, -CR^*= CR^*-, -CR^* ₂SiR^* ₂-, -GeR^* ₂-Etc. However, R^*Is a hydrogen atom, a hydrocarbon group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 8 carbon atoms, a silyl group, a halogenated alkyl group having 1 to 8 carbon atoms, a halogenated aryl group having 6 to 20 carbon atoms, Or these composite groups are represented.
  Specific examples of bonding of two cyclic η-bonding anion ligands include ethylene bis (cyclopentadienyl) titanium dichloride, ethylene bis (tetramethylcyclopentadienyl) titanium dichloride, ethylene bis (indenyl) titanium. Dichloride, ethylenebis (4,5,6,7-tetrahydro-1-indenyl) titanium dichloride, ethylenebis (4-methyl-1-indenyl) titanium dichloride, ethylenebis (5-methyl-1-indenyl) titanium dichloride, Ethylenebis (6-methyl-1-indenyl) titanium dichloride, ethylenebis (7-methyl-1-indenyl) titanium dichloride, ethylenebis (5-methoxy-1-indenyl) titanium dichloride, ethyl Bis (2,3-dimethyl-1-indenyl) titanium dichloride, ethylenebis (4,7-dimethyl-1-indenyl) titanium dichloride, ethylenebis (4,7-dimethoxy-1-indenyl) titanium dichloride, methylenebis (cyclo Pentadienyl) titanium dichloride, isopropylidenebis (cyclopentadienyl) titanium dichloride, isopropylidene (cyclopentadienyl) (fluorenyl) titanium dichloride, silylene bis (cyclopentadienyl) titanium dichloride, dimethylsilylene bis (cyclopentadi) Enyl) titanium dichloride, dimethylsilylene bis (tetramethylcyclopentadienyl) titanium dichloride, dimethylsilylene bis (methylcyclopenta) Dienyl) titanium dichloride, dimethylsilylene bis (trimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (cyclopentadienyl) (fluorenyl) titanium dichloride, dimethylsilylene (cyclopentadienyl) (indenyl) titanium dichloride, dimethylsilylene (tetra Methylcyclopentadienyl) (fluorenyl) titanium dichloride, dimethylsilylene (tetramethylcyclopentadienyl) (indenyl) titanium dichloride, dimethylsilylene (tetramethylcyclopentadienyl) (cyclopentadienyl) titanium dichloride, dimethylsilylene ( Fluorenyl) (indenyl) titanium dichloride, dimethylsilylene (tetramethylcyclope) Tadienyl) (trimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (tetramethylcyclopentadienyl) (3,5-bistrimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (cyclopentadienyl) (trimethylsilylcyclopentadienyl) Enyl) titanium dichloride, dimethylsilylene (tetramethylcyclopentadienyl) (3,5-bistrimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (fluorenyl) (trimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (fluorenyl) (3,5-bistrimethylsilylcyclopentadienyl) titanium dichloride, dimethylsilylene (indene Le) (trimethylsilyl cyclopentadienyl) titanium dichloride, dimethylsilylene (indenyl) (3,5-bis-trimethylsilyl cyclopentadienyl) titanium dichloride and the like.
  Specific examples of the half titanocene compound used in the present invention include the following compounds when the cyclic η-bonding anion ligand is a cyclopentadienyl group.
  Cyclopentadienyl titanium trimethyl, cyclopentadienyl titanium triethyl, cyclopentadienyl titanium triisopropyl, cyclopentadienyl titanium tri-n-butyl, cyclopentadienyl titanium tri-sec-butyl, cyclopentadienyl titanium tri Methoxide, cyclopentadienyl titanium triethoxide, cyclopentadienyl titanium triisopropoxide, cyclopentadienyl titanium tributoxide, cyclopentadienyl titanium triphenyl, cyclopentadienyl titanium tri-m-tolyl, cyclo Pentadienyl titanium tri-p-tolyl, cyclopentadienyl titanium tri-m, p-xylyl, cyclopentadienyl titanium tri-4-ethyl phen , Cyclopentadienyl titanium tri-4-hexylphenyl, cyclopentadienyl titanium tri-4-methoxyphenyl, cyclopentadienyl titanium tri-4-ethoxyphenyl, cyclopentadienyl titanium triphenoxide, cyclopentadienyl Titanium trifluoride, cyclopentadienyl titanium tribromide, cyclopentadienyl titanium trichloride, cyclopentadienyl titanium tribromide, cyclopentadienyl titanium triiodide, cyclopentadienyl titanium methyl dichloride, cyclopentadienyl titanium Dimethyl chloride, cyclopentadienyl titanium ethoxide dichloride, cyclopentadienyl titanium diethoxide chloride Id, cyclopentadienyl titanium phenoxide dichloride, cyclopentadienyl titanium diphenoxide chloride, cyclopentadienyl titanium tribenzyl, cyclopentadienyl titanium tri-dimethylamide, cyclopentadienyl titanium tri-diethylamide, cyclopentadienyl Titanium tri-diisopropylamide, cyclopentadienyl titanium tri-di-sec-butyramide, cyclopentadienyl titanium tri-di-tert-butyramide, cyclopentadienyl titanium tri-ditrimethylsilylamide and the like.
  As specific examples of the half titanocene compound used in the present invention, the above-mentioned “cyclopentadienyl” moiety may be substituted with any cyclic η-bonding anion as described in the specific example of the titanocene compound. A compound having a name formed by replacing the ligand is also included.
  Furthermore, the half titanocene compounds listed below are also included.
  [(N-tert-butyramide) (tetramethylcyclopentadienyl) -1,2-ethanediyl] titanium dichloride, [(N-tert-butyramide) (tetramethylcyclopentadienyl) dimethylsilane] titanium dichloride, [( N-methylamido) (tetramethylcyclopentadienyl) dimethylsilane] titanium dichloride, [(N-phenylamido) (tetramethylcyclopentadienyl) dimethylsilane] titanium dichloride, [(N-benzylamido) (tetramethylcyclo Pentadienyl) dimethylsilane] titanium dichloride, [(N-tert-butylamide) (cyclopentadienyl) -1,2-ethanediyl] titanium dichloride, [(N-tert-butylamide) (cyclo Ntadienyl) dimethylsilane] titanium dichloride, [(N-methylamido) (cyclopentadienyl) -1,2-ethanediyl] titanium dichloride, [(N-methylamido) (cyclopentadienyl) dimethylsilane] titanium dichloride, [( N-tert-butylamide) (indenyl) dimethylsilane] titanium dichloride, [(N-benzylamido) (indenyl) dimethylsilane] titanium dichloride, and the like.
  In addition, compounds having names obtained by replacing the “dichloride” portion of these half titanocene compounds with arbitrary ones listed as titanocene compounds are also included.
  These titanocene compounds or half titanocene compounds can be used alone or in combination. Among these, hydrogenation activity is high, and preferred compounds include bis (cyclopentadienyl) titanium dichloride, bis (cyclopentadienyl) titanium di-m-tolyl, and bis (cyclopentadienyl) titanium di-p. -Tolyl.
  Further, the titanocene compound or the half titanocene compound is preferable because the hydrogenation activity can be further improved by mixing and reacting with organic lithium, organic magnesium, or organic aluminum.
  As organolithium that can be mixed and reacted with a titanocene compound or a half titanocene compound, RLi (wherein R is an alkyl group having 1 to 10 carbon atoms, an alkoxy group or an alkylamide group, an aryl group having 6 to 12 carbon atoms, an allyloxy group) Alternatively, an arylamide group, an alkylaryl group having 7 to 20 carbon atoms, an alkyl allyloxy group or an alkylarylamide group, an arylalkyl group having 7 to 20 carbon atoms, an arylalkoxy group, an arylalkylamide group, and 2 to 20 carbon atoms A hydrocarbon group selected from the group consisting of alkenyl groups of
  Specific examples of such organic lithium include methyl lithium, ethyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, methoxy lithium, ethoxy lithium, isopropoxy lithium, butoxy lithium, dimethylamide. Lithium, diethylamidolithium, diisopropylamidolithium, dibutylamidolithium, diphenylamidolithium, phenyllithium, m-tolyllithium, p-tolyllithium, xylyllithium, methoxyphenyllithium, phenoxylithium, 4-methylphenoxylithium, 2,6 -Monolithium compounds such as diisopropylphenoxylithium, 2,4,6-triisopropylphenoxylithium, and benzyllithium.
  Moreover, the oligomer which has terminal living activity which added a small amount of monomers using said monolithium compound as an initiator, for example, polybutadienyl lithium, polyisoprenyl lithium, polystyryl lithium, etc. are mentioned. Further, a compound having two or more lithium atoms in one molecule, for example, a dilithium compound which is a reaction product of diisopropenylbenzene and sec-butyllithium, divinylbenzene, sec-butyllithium and a small amount of 1,3-butadiene. And a multi-lithium compound which is a reaction product of These organolithiums can be used alone or in combination. As addition amount with respect to a titanocene compound or a half titanocene compound, the range of 0.1-10 is preferable at Li / Ti (molar ratio). More preferably, it is the range of 0.2-5.
  Examples of the organic magnesium that can be mixed and reacted with the titanocene compound or the half titanocene compound include dialkyl magnesium and alkyl halogen magnesium represented by Grignard reagent. Specific examples thereof include dimethyl magnesium, diethyl magnesium, dibutyl magnesium, ethyl butyl magnesium, dihexyl magnesium, methyl magnesium bromide, methyl magnesium chloride, ethyl magnesium bromide, ethyl magnesium chloride, butyl magnesium bromide, butyl magnesium chloride, hexyl magnesium bromide, Examples include cyclohexyl magnesium bromide, phenyl magnesium bromide, phenyl magnesium chloride, allyl magnesium bromide, and allyl magnesium chloride.
  These organomagnesiums can be used alone or in combination. As addition amount with respect to a titanocene compound or a half titanocene compound, the range of 0.1-10 is preferable at Mg / Ti (molar ratio). More preferably, it is the range of 0.2-5.
  Examples of the organic aluminum that can be mixed and reacted with the titanocene compound or the half titanocene compound include trialkylaluminum, dialkylaluminum chloride, and alkylmagnesium dichloride. Specific examples include trimethylaluminum, triethylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, dimethylaluminum chloride, diethylaluminum chloride, methylaluminum dichloride, ethylaluminum dichloride, diethylethoxyaluminum. Etc. can be used.
  These organoaluminums can be used alone or in combination. As addition amount with respect to a titanocene compound or a half titanocene compound, the range of 0.1-10 is preferable at Al / Ti (molar ratio). More preferably, it is the range of 0.2-5.
  Among these combinations, a mixture / reaction product of a titanocene compound and organoaluminum has a particularly high hydrogenation ability and can be suitably used in the present invention. In this case, it is presumed that a metallacycle compound is formed by the titanocene compound and the organoaluminum to form a Teve type complex. A Tebbe type complex obtained by selecting titanocene dichloride as the titanocene compound and trimethylaluminum as the organic aluminum and mixing and reacting at 1: 2 (molar ratio) also has high hydrogenation ability. This TB type complex may be used as it is isolated from the reaction mixture or the reaction mixture may be used as it is, but the method of using the reaction mixture as it is can eliminate the troublesome work of isolating the industrial process. Is advantageous.
  Since the reaction between such a titanocene compound and organoaluminum is a relatively slow reaction, it is necessary to take a sufficient time. Specifically, a titanocene compound is dispersed or dissolved in an inert solvent, an organoaluminum compound is added, and the mixture is sufficiently stirred and reacted at a temperature of 0 ° C to 100 ° C. If the reaction temperature is too low, it takes too much time. On the other hand, if the reaction temperature is too high, side reactions are likely to occur and the hydrogenation ability is reduced. The temperature is preferably 10 ° C to 50 ° C. In addition, since the reaction proceeds in two steps, it is necessary to spend a day or more at room temperature.
  In order to further enhance the hydrogenation ability of these titanocene compounds or half titanocene compounds, alcohols, ethers, amines, ketones, phosphorus compounds and the like can be added as the second component or the third component.
  Examples of alcohols for enhancing the hydrogenation ability of the titanocene compound or the half titanocene compound include methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, phenol, and glycols such as ethylene glycol.
  Examples of ethers for enhancing the hydrogenation ability of titanocene compounds or half titanocene compounds include dimethyl ether, diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, diphenyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, etc. And silyl ethers such as bistrimethylsilyl ether.
  Examples of amines for enhancing the hydrogenation ability of titanocene compounds or half titanocene compounds include secondary amines such as dimethylamine, diethylamine, diisopropylamine, dibutylamine, diphenylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine. And tertiary amines such as triphenylamine, N, N, N ′, N′-tetramethylethylenediamine, and the like.
  Examples of ketones for enhancing the hydrogenation ability of the titanocene compound or the half titanocene compound include dimethyl ketone, diethyl ketone, methyl ethyl ketone, methyl phenyl ketone, and ethyl phenyl ketone.
  Examples of the phosphorus compound for enhancing the hydrogenation ability of the titanocene compound or the half titanocene compound include phosphorus compounds capable of coordinating with titanocene. Examples thereof include trimethylphosphine, triethylphosphine, and triphenylphosphine.
  These compounds for enhancing the hydrogenation ability of the titanocene compound or the half titanocene compound can be used alone or in combination. As addition amount with respect to a titanocene compound or a half titanocene compound, it is the range of 0.01-10 in molar ratio with respect to Ti. Preferably, it is the range of 0.02-5. More preferably, it is the range of 0.02-1.
  As the compound (D) having hydrogenation ability of the present invention, in addition to the above titanocene compound, a compound containing platinum, palladium, palladium-chromium, nickel, ruthenium can also be used. Preferably, it is a Teve reagent or a Teve type complex.
  In the present invention, the compound (D) having hydrogenation ability may be used for polymerization after previously contacting with the metallocene catalyst (C), or may be separately introduced into the polymerization reactor. The amount of each component used and the ratio of the amounts used are not particularly limited, but the molar ratio of the metal in the compound (D) having the ability to add hydrogen to the transition metal in the metallocene catalyst (C) is 0.01 to 1000. Preferably, it is 0.1-10. When the amount of the compound (D) having hydrogenation ability is small, the molecular weight is not improved, and when too large, the polymerization activity is lowered.
  The ultra high molecular weight ethylene polymer of the present invention can be molded using the same molding method as that of ordinary ultra high molecular weight polyethylene. For example, the ultra-high molecular weight polyethylene powder of the present invention is obtained by various known molding methods such as a method in which ultra-high molecular weight polyethylene powder is placed in a mold and compression-molded with heating for a long time or extrusion molding with a ram extruder. be able to.
  In addition, in the ultra-high molecular weight ethylene polymer molded product of the present invention, the ultra high molecular weight ethylene polymer is mixed with an appropriate solvent or plasticizer, extruded into a film, stretched, and then used as a solvent or Also included are microporous films made by extracting a plasticizer. This film can be used for battery separators and the like. In this case, a film mixed with an inorganic material such as silica can be used.
  Furthermore, the ultra-high molecular weight ethylene polymer powder of the present invention is dissolved or mixed in an appropriate solvent or plasticizer to prepare a gel mixture, and ultra-high elastic modulus and high-strength fibers are obtained by a known gel spinning technique. You can also.
Examples 1-9 and Comparative Examples 1-4
  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited in any way by these examples. In addition, the measuring method used by each Example and the comparative example is as follows.
  [Measurement of Mw / Mn]
  150-CA LC / GPC apparatus (manufactured by Waters), Shodex AT-807S (manufactured by Showa Denko KK) and TSK-gel GMH-H16 (manufactured by Tosoh Corporation) are used in series as a column, and 10 ppm of Irganox 1010 is used as a solvent. It measured at 140 degreeC using the containing trichlorobenzene. A calibration curve was prepared using commercially available monodisperse polystyrene as a standard substance.
  [Measurement of viscosity average molecular weight]
  20 mg of decalin was charged with 2 mg of polymer and stirred at 150 ° C. for 2 hours to dissolve the polymer. Using a Ubbelohde viscometer, the solution was dropped at a high temperature of 135 ° C., and the drop time between the marked lines (t_s) Was measured. In addition, the fall time (t of only decahydronaphthalene which does not put the polymer as a blank (t_b) Was measured. The specific viscosity of the polymer (η_sp/ C) was plotted, and the intrinsic viscosity (η) extrapolated to a concentration of 0 was determined.
  η_sp/ C = (t_s/ T_b-1) /0.1
From this intrinsic viscosity (η), the viscosity average molecular weight (Mv) was determined according to the following formula.
  Mv = 5.34 × 10⁴η^1.49
  [Density measurement]
  Measured according to ASTM D1505. As a test piece, a section cut from a press sheet was annealed at 120 ° C. for 1 hour and then cooled to room temperature over 1 hour.
    [Measurement of HAZE]
  A press sheet having a thickness of 0.7 mm was prepared and measured by the method of ASTM D1003 using a test piece left at 23 ° C. ± 1 ° C. for 24 hours. <Measurement equipment (Murakami Color Research Laboratory, grade name HM-100) Sample size 50 mm (w) * 10 mm (t) * 50 mm (h), compliant with optical system ASTM D1003>
[Measurement of crystallinity]
  Using a differential scanning calorimeter DSC7 (manufactured by Perkin Elmer), after holding at 50 ° C. for 1 minute, the temperature was raised to 180 ° C. at a rate of 200 ° C./minute, held at 180 ° C. for 5 minutes, then 10 ° C. / The temperature was lowered to 50 ° C. in minutes. After maintaining at 50 ° C. for 5 minutes, the temperature was raised to 180 ° C. at 10 ° C./min, and in the melting curve obtained at that time, a baseline was drawn from 60 ° C. to 145 ° C. to determine melting enthalpy (J / g). The value obtained by dividing this by 293 (J / g) and multiplying by 100 was taken as the crystallinity (%).
  [Measurement of terminal vinyl group content]
  Ultra high molecular weight polyethylene powder was pressed at 180 ° C. to prepare a film. The infrared absorption spectrum (IR) of this film was measured using FT-IR5300A (manufactured by JASCO Corporation). The vinyl group is 910cm^-1Was calculated according to the following formula from the absorbance (ΔA) and the film thickness (t (mm)) of the peak.
  Amount of vinyl group (pieces / 1000 C) = 0.98 × ΔA / t
[Measurement of amount of residual Ti and Cl]
An appropriate amount of ultra high molecular weight ethylene polymer powder was sampled, and nitric acid was added for decomposition. Pure water was added to this decomposed product to prepare a measurement sample. A commercially available standard solution for atomic absorption analysis was diluted with an aqueous nitric acid solution and used as a standard solution. ICP measurement was performed using JY138 (manufactured by Rigaku Corporation).
[Calculation formula for calculated value 1]
  The calculated value 1 was obtained from the viscosity average molecular weight Mv by the following formula.
  Calculated value 1 = −9 × 10^-10× Mv + 0.937
  [Calculation formula for calculated value 2]
  The calculated value 2 was obtained from the density ρ (g / cc) by the following formula.
  Calculated value 2 = 630ρ−530

(Preparation of compound (D) having hydrogenation ability)
A 3 wt% hexane suspension of 30 mmol titanocene dichloride manufactured by Wako Pure Chemical Industries, Ltd. and 60 mmol of a 1M hexane solution of trimethylaluminum were stirred at room temperature for 100 hours to prepare a Tebbe reagent.
(Ethylene polymerization: Preparation of ethylene homopolymer (A))
Isobutane, ethylene, hydrogen, a metallocene-based catalyst and a Tebbe reagent were continuously supplied to a Bessel type polymerization reactor equipped with a stirrer to produce polyethylene (ethylene homopolymer) at a rate of 10 kg / Hr. Hydrogen having a purity of 99.99 mol% or more purified by contact with molecular sieves was used. Metallocene catalysts include [(Nt-butylamide) (tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] titanium-1,3-pentadiene and bis (hydrogenated tallow alkyl) methylammonium tris (penta A mixture of fluorophenyl) (4-hydroxyphenyl) borate and triethylaluminum supported on silica treated with triethylaluminum was used. Isobutane as a solvent was supplied at 32 L / Hr. The metallocene catalyst was supplied so that the production rate was 10 kg / Hr together with 10 NL / Hr of hydrogen (NL is a normal liter (volume converted to the standard state)) using the above solvent isobutane as a transfer liquid. The Tebbe reagent was supplied at 0.13 mmol / Hr by a separate line from the metallocene catalyst. The polymerization slurry was continuously withdrawn so that the level of the polymerization reactor was kept constant, and the withdrawn slurry was sent to the drying process. There was no presence of bulk polymer, and the slurry removal piping was not blocked, and stable continuous operation was possible. The catalytic activity was 5000 g PE / g catalyst. The polyethylene thus obtained had an average molecular weight of 9.2 million, a density of 0.9272 g / cc, and a crystallinity of 46%, as determined from the intrinsic viscosity in decalin (135 ° C.). Table 1 shows the measurement results regarding this example, including other values.

  The same procedure as in Example 1 was performed except that the Tube reagent was supplied at 0.013 mmol / Hr. Also in this case, no bulk polymer was produced, and the slurry removal piping was not blocked, and the continuous operation was stable. The obtained polyethylene had an average molecular weight of 2.1 million, a density of 0.9300 g / cc, and a crystallinity of 52%, as determined from the intrinsic viscosity in decalin (135 ° C.). Table 1 shows the measurement results regarding this example, including other values.

  The same procedure as in Example 1 was performed except that the Tube reagent was supplied at 0.38 mmol / Hr. Also in this case, no bulk polymer was produced, and the slurry removal piping was not blocked, and the continuous operation was stable. The obtained polyethylene had an average molecular weight of 11 million, a density of 0.9235 g / cc, and a crystallinity of 42%, as determined from the intrinsic viscosity in decalin (135 ° C.). Table 1 shows the measurement results regarding this example, including other values.

The same procedure as in Example 1 was performed except that the Tube reagent was supplied at 0.038 mmol / Hr. Also in this case, no bulk polymer was produced, and the slurry removal piping was not blocked, and the continuous operation was stable. The obtained polyethylene had an average molecular weight of 4.4 million, a density of 0.9275 g / cc, and a crystallinity of 48%, as determined from the intrinsic viscosity in decalin (135 ° C.). Table 1 shows the measurement results regarding this example, including other values.
Comparative Example 1
In place of the metallocene catalyst, ethylene was prepared in the same manner as in Example 1 except that a Ziegler catalyst prepared according to the method described in Japanese Patent Publication No. 52-36788 (denoted as ZN catalyst in Table 1) was used. Polymerization was performed. The catalytic activity was 7000 g PE / g catalyst. The resulting polyethylene had a viscosity average molecular weight of 2 million, a density of 0.939 g / cc, and a crystallinity of 64%, as determined from the intrinsic viscosity in decalin (135 ° C.). Table 1 shows the measurement results regarding this comparative example, including other values.
Comparative Example 2
In Example 1, a metallocene catalyst prepared according to the method described in Example 1 of JP-A No. 09-291112 was used as the metallocene catalyst, and ethylene was polymerized without feeding the Teve reagent. The obtained polyethylene did not have an ultrahigh molecular weight, and the value of the melt index measured at 190 ° C. and a load of 2.16 kg was 1.0 g / 10 min. Table 1 shows the measurement results regarding this comparative example, including other values.
In addition, an experiment was attempted in which the hydrogen feed amount was decreased from 10 NL / Hr in order to increase the molecular weight, but the slurry extraction piping was blocked and the operation was stopped.

(Copolymerization of ethylene / hexene-1: Preparation of ethylene copolymer (B))
Isobutane, ethylene, hexene-1, hydrogen, metallocene catalyst, and Teve reagent were continuously supplied to a Bessel type polymerization reactor equipped with a stirrer to produce an ultra high molecular weight ethylene copolymer at a rate of 10 kg / Hr. . Hydrogen having a purity of 99.99 mol% or more purified by contact with molecular sieves was used. Metallocene catalysts include [(Nt-butylamide) (tetramethyl-η ⁵ -cyclopentadienyl) dimethylsilane] titanium-1,3-pentadiene and bis (hydrogenated tallow alkyl) methylammonium tris (penta A mixture of fluorophenyl) (4-hydroxyphenyl) borate and triethylaluminum supported on silica treated with triethylaluminum was used. Isobutane as a solvent was supplied at 30 L / Hr. The metallocene catalyst was supplied using the above-mentioned solvent isobutane as a transfer liquid together with 10 NL / Hr of hydrogen so that the production rate was 10 kg / Hr. The Tebbe reagent was supplied at 45 μmol / Hr by a separate line from the metallocene catalyst. The hexene-1 purified by contact with molecular sieves was supplied at 0.35 L / Hr. The polymerization slurry was continuously withdrawn so that the level of the polymerization reactor was kept constant, and the withdrawn slurry was sent to the drying process. There was no presence of bulk polymer, and the slurry removal piping was not blocked, and stable continuous operation was possible. The catalytic activity was 4000 g PE / g catalyst. The polyethylene thus obtained had an average molecular weight of 4.8 million, a density of 0.919 g / cc, and a crystallinity of 37%, as determined from the intrinsic viscosity in decalin (135 ° C.). HAZE as an index of transparency was 42%. Table 2 shows the measurement results regarding this example, including other values.

  The same procedure as in Example 5 was performed except that the Tube reagent was supplied at 75 μmol / Hr. The obtained polyethylene had an average molecular weight of 6,800,000, a density of 0.917 g / cc, and a crystallinity of 37%, as determined from the intrinsic viscosity in decalin (135 ° C.). HAZE as an index of transparency was 41%. Table 2 shows the measurement results regarding this example, including other values.

  The same procedure as in Example 5 was carried out except that hexene-1 was supplied at 1.10 L / hr and the Tebbe reagent was supplied at 100 μmol / Hr. The obtained polyethylene had an average molecular weight of 6,200,000, a density of 0.905 g / cc, and a crystallinity of 17%, as determined from the intrinsic viscosity in decalin (135 ° C.). HAZE as an index of transparency was 20%. Table 2 shows the measurement results regarding this example, including other values.

  The same procedure as in Example 5 was conducted, except that hexene-1 was supplied at 1.80 L / hr and the Tebbe reagent was supplied at 150 μmol / Hr. The obtained polyethylene had an average molecular weight of 4.8 million, a density of 0.885 g / cc, and a crystallinity of 8%, as determined from the intrinsic viscosity in decalin (135 ° C.). HAZE as an index of transparency was 15%. Table 2 shows the measurement results regarding this example, including other values.

(Copolymerization of ethylene / butene-1: Preparation of ethylene copolymer (B))
The same procedure as in Example 5 was conducted except that butene-1 was used in place of hexene-1, butene-1 was supplied at 1.00 L / hr, and the Tebbe reagent was supplied at 45 μmol / Hr. The obtained polyethylene had an average molecular weight of 5.1 million, a density of 0.916 g / cc, and a crystallinity of 35%, as determined from the intrinsic viscosity in decalin (135 ° C.). HAZE as an index of transparency was 32%. Table 2 shows the measurement results regarding this example, including other values.
Comparative Example 3
Instead of the metallocene catalyst, a Ziegler catalyst prepared in accordance with the method described in Japanese Patent Publication No. 52-36788 (denoted as ZN catalyst in Table 2) was used, and Example 5 was used except that a Teve catalyst was not used. Similarly, ethylene was polymerized. The catalytic activity was 7000 g PE / g catalyst. The average molecular weight of the obtained polyethylene determined from the intrinsic viscosity in decalin (135 ° C.) was 3 million, the density was 0.930 g / cm ³ , the density was higher than that of Example 5, the crystallinity was 45%, and the transparency HAZE, which is an index of, was 56%, which was inferior in transparency compared to Example 5. Table 2 shows the measurement results regarding this comparative example, including other values.
Comparative Example 4
Ethylene was polymerized in the same manner as in Example 5 except that the Teve catalyst was not used. The catalytic activity was 4000 g PE / g catalyst. The average molecular weight of the obtained polyethylene determined from the intrinsic viscosity in decalin (135 ° C.) was 150,000, which was very low compared to Example 5, and the density was 0.946 g / cm ³ , which was higher than that of Example 5. The crystallinity was 40%, and HAZE as an index of transparency was 45%. Table 2 shows the measurement results regarding this comparative example, including other values.

  The ultra-high molecular weight ethylene polymer of the present invention has a molecular weight distribution larger than 3, a small amount of residual Ti and residual Cl in the polymer, wear characteristics such as wear resistance and low friction, and mechanical properties such as strength. Excellent balance of physical properties, moldability and thermal stability during molding. From such characteristics, sliding members such as gears, bearing members, artificial joint substitutes, ski sliding surfaces, abrasives, slip sheets of various magnetic tapes, flexible disk liners, bulletproof members, battery separators, various It can be suitably used in the fields of filters, foams, films, pipes, fibers, threads, fishing lines, cutting boards and the like. Furthermore, the ultra high molecular weight ethylene polymer of the present invention can reduce density and crystallinity while maintaining the ultra high molecular weight, and is excellent in transparency and flexibility as compared with conventional polymers. Yes. Therefore, it is particularly useful as a ski sliding surface material. Moreover, the ultra high molecular weight ethylene polymer can be stably produced over a long period of time by a commercial process by the production method of the present invention.

Claims (4)

An ethylene homopolymer (A); and an ethylene copolymer (B),
a) 99.9 to 75.0% by weight of ethylene,
b) an α-olefin having 3 to 20 carbon atoms, a cyclic olefin having 3 to 20 carbon atoms, a compound represented by the formula CH ₂ ═CHR (where R is an aryl group having 6 to 20 carbon atoms), and The ethylene copolymer obtained by copolymerizing 0.1 to 25.0% by weight of a comonomer that is at least one olefin selected from the group consisting of linear, branched or cyclic dienes having 4 to 20 carbon atoms. Polymer (B);
An ethylene polymer that is any one of
i) viscosity average molecular weight is 1 million or more,
ii) the molecular weight distribution (Mw / Mn) is greater than 3, and
iii) a method for producing an ultrahigh molecular weight ethylene polymer having a Ti content of 3 ppm or less and a Cl content of 5 ppm or less in the polymer,
A metallocene system formed by using a compound represented by the following formula (6), a compound represented by the following formula (7), and an organoaluminum compound, which has been previously contacted with a hydrogenating agent when polymerizing one or more olefins. A method for producing an ultrahigh molecular weight ethylene polymer using a catalyst (C) and a compound (D) having hydrogenation ability.
Formula (6):

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anion ligand, and the ligand has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, 12 halogen-substituted hydrocarbon groups, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, a hydrocarbyl phosphino group having 1 to 12 carbon atoms, 1 to 20 non-hydrogen atoms selected from the group consisting of a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group It is a substituent,
M is a transition metal selected from the group of transition metals belonging to Group 4 of the periodic table having a formal oxidation number of +2, +3, or +4, and represents a transition metal bonded to at least one ligand L by η ^5. ,
W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and M with a valence of 1 each, thereby cooperating with L and M to form a metallacycle. Represents a divalent substituent that forms
X is each independently a monovalent anionic σ-bonded ligand, a divalent anionic σ-bonded ligand that binds to M bivalently, and L and M each monovalently An anionic σ-bonded ligand having 1 to 60 non-hydrogen atoms, selected from the group consisting of divalent anionic σ-bonded ligands bonded by a valence;
X ′ each independently represents a neutral Lewis base coordination compound having 1 to 40 non-hydrogen atoms,
j is 1 or 2, provided that when j is 2, two ligands L are bonded to each other via a divalent group having 1 to 20 non-hydrogen atoms, and the divalent The group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, a hydrocarbyleneamino group having 1 to 12 carbon atoms, and a silanediyl group. A group selected from the group consisting of a group, a halosilanediyl group, and a silyleneamino group,
k is 0 or 1,
p is 0, 1 or 2, provided that X is a monovalent anionic σ-bonded ligand or a divalent anionic σ-bonded ligand bonded to L and M , P is an integer 1 or more smaller than the formal oxidation number of M, and when X is a divalent anionic σ-bonded ligand bonded only to M, p is smaller than the formal oxidation number of M ( j + 1) or larger integer, q is 0, 1 or 2. )
Formula (7):

(Wherein [L-H] ^{d +} represents a proton-donating Bronsted acid, wherein L represents a neutral Lewis base, d is an integer of 1 to 7; [M _m Q _p ] ^{d -} represents a non-coordinating anion of compatibility, where, M represents a metal or metalloid belonging to any of the fifth to group 15 of the periodic table, Q is each independently hydride, halide, Selected from the group consisting of a dihydrocarbylamide group having 2 to 20 carbon atoms, a hydrocarbyloxy group having 1 to 30 carbon atoms, a hydrocarbon group having 1 to 30 carbon atoms, and a substituted hydrocarbon group having 1 to 40 carbon atoms. However, in the above formula (7), each Q independently selected from Q is 0 or 1, m is an integer of 1 to 7, and p is an integer of 2 to 14. And d is as defined above, and pm = d.) The hydrogenating agent is hydrogen and / or at least one type of R _n SiH _4-n (wherein 0 ≦ n ≦ 1, R is an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, And a hydrocarbon group selected from the group consisting of an alkylaryl group having 7 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, and an alkenyl group having 2 to 20 carbon atoms. The method described.   Reaction of compound (D) having hydrogenation ability with titanocene compound alone, half titanocene compound alone, or one or more organic metal compounds selected from organic lithium, organic magnesium, and organic aluminum with titanocene compound or half titanocene compound The method of claim 1, which is a mixture. The titanocene compound or the half titanocene compound is represented by the following formula (8):

(In the formula, each L is independently a cyclic η selected from the group consisting of a cyclopentadienyl group, an indenyl group, a tetrahydroindenyl group, a fluorenyl group, a tetrahydrofluorenyl group, and an octahydrofluorenyl group. Represents a binding anion ligand, and the ligand has 1 to 8 substituents, each of which is independently a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, 12 halogen-substituted hydrocarbon groups, an aminohydrocarbyl group having 1 to 12 carbon atoms, a hydrocarbyloxy group having 1 to 12 carbon atoms, a dihydrocarbylamino group having 1 to 12 carbon atoms, a hydrocarbyl phosphino group having 1 to 12 carbon atoms, 1 to 20 non-hydrogen atoms selected from the group consisting of a silyl group, an aminosilyl group, a hydrocarbyloxysilyl group having 1 to 12 carbon atoms, and a halosilyl group It is a substituent,
Ti represents titanium having a formal oxidation number of +2, +3, or +4 and η ⁵ bonded to at least one ligand L;
W is a divalent substituent having 1 to 50 non-hydrogen atoms, and is bonded to L and Ti at a valence of 1 each, thereby cooperating with L and Ti to form a metallacycle. Represents a divalent substituent that forms
X and X ′ are each independently a monovalent ligand, a divalent ligand that binds divalently to Ti, and a divalent bond that binds to L and Ti each with a monovalent valence. A ligand selected from the group consisting of: a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogen atom, a halogen-substituted hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Aminohydrocarbyl group, hydrocarbyloxy group having 1 to 12 carbon atoms, dihydrocarbylamino group having 1 to 12 carbon atoms, hydrocarbylphosphino group having 1 to 12 carbon atoms, silyl group, aminosilyl group, hydrocarbyl having 1 to 12 carbon atoms Represents a ligand having 1 to 20 non-hydrogen atoms selected from the group consisting of an oxysilyl group and a halosilyl group;
j is 1 or 2, provided that when j is 2, two ligands L are bonded to each other via a divalent group having from 1 to 20 non-hydrogen atoms, said divalent The group includes a hydrocarbadiyl group having 1 to 20 carbon atoms, a halohydrocarbadiyl group having 1 to 12 carbon atoms, a hydrocarbyleneoxy group having 1 to 12 carbon atoms, a hydrocarbyleneamino group having 1 to 12 carbon atoms, and a silanediyl group. A group selected from the group consisting of a group, a halosilanediyl group, and a silyleneamino group,
k is 0 or 1,
p is 0, 1 or 2, provided that when X is a monovalent ligand or a divalent ligand bonded to L and Ti, p is 1 from the formal oxidation number of Ti. When X is a divalent anionic σ-bonded ligand bonded only to Ti, p is an integer smaller than (j + 1) or more than the formal oxidation number of Ti, and q is 0, 1 or 2. )
The method of Claim 3 which is at least 1 sort (s) of compound represented by these.