JP3943422B2 - Propylene block copolymer - Google Patents

Description

【００２１】
また、本発明のプロピレンブロック共重合体は、平均粒径１００〜５０００μm の粒子状物であって、その粒子表面上に析出しているエチレン−プロピレン共重合体が、全体のエチレン−プロピレン共重合体の０．３容量％以下、好ましくは０．２容量％以下、特に好ましくは０．１容量％以下であり、共重合体粒子の表面上に存在するゴム部が非常に少ないという特徴を有する。従来のプロピレンブロック共重合体あるいはその製造方法では、ゴム部の割合が低い場合、重合体粒子の内部、あるいはＰＰ部のマトリックス内部にゴム部が生成し、重合体粒子の表面には析出してこないが、ゴム部の割合が高い場合、ＰＰ部に割れが生じてゴム部が重合体表面に析出してしまう。そのため重合体粒子は付着性を示し、結果として重合体粒子同士が付着し凝集したり、反応槽内壁あるいは移送配管内壁などに付着しトラブルの原因となっていた。本発明のプロピレンブロック共重合体では、ゴム部の割合が５０重量％以上と高い場合であっても、ゴム部がほとんど重合体粒子表面上になく、付着性がほとんど見られない。粒子表面に析出しているゴム部の割合は、ＴＥＭ（透過型電子顕微鏡）による重合体の断面写真の画像解析により求められ、粒子表面に析出しているゴム部の面積及び全体のゴム部の面積から容量に換算して算出する。
【００２２】
次に、本発明のプロピレンブロック共重合体の製造方法について説明する。本発明のプロピレンブロック共重合体は、２段階以上の多段重合により行い、通常第１段目で重合用触媒の存在下にプロピレンを重合し、第２段目でエチレン及びプロピレンを共重合することにより得られる。第２段目あるいはこれ以降の重合時にプロピレン以外のα−オレフィンを共存あるいは単独で重合させることも可能である。α−オレフィンの例としては、エチレン、１−ブテン、４−メチル−１−ペンテン、ビニルシクロヘキサン、１−ヘキセン、１−オクテン等が挙げられる。具体的には、第１段目でＰＰ部割合が２０〜８０重量％になるように重合温度および時間を調整して重合し、次いで、第２段目においてエチレンおよびプロピレンあるいは他のα−オレフィンを導入して、ゴム部割合が２０〜８０重量％になるように重合する。第１段目及び第２段目における重合温度は共に、２００℃以下、好ましくは１００℃以下であり、重合圧力は１０ＭＰａ以下、好ましくは５ＭＰａ以下である。また、各重合段階での重合時間あるいは連続重合の場合、滞留時間は通常１分〜５時間である。重合方法としては、シクロヘキサン、ヘプタン等の不活性炭化水素の溶媒を試用するスラリー重合法、液化プロピレン等の溶媒を使用するバルク重合法、及び実質的に溶媒を使用しない気相重合法が挙げられる。好ましい重合方法としては、バルク重合法、気相重合法である。
【００２３】
本発明のプロピレンブロック共重合体の製造に用いられる重合用触媒としては、マグネシウム、チタン、ハロゲン及び電子供与性化合物を含む固体触媒成分と、有機アルミニウム化合物、また、必要に応じて外部電子供与性化合物を組合せた触媒が用いられる。
【００２４】
上述したような本発明のプロピレンブロック共重合体の新規で特異な構造は、重合に使用する固体触媒成分の構造に主に起因するものであり、表２に示すような粒子特性を有するマグネシウム、チタン、ハロゲン及び電子供与性化合物を含む固体触媒成分が用いられる。比表面積及び細孔容積はＢＥＴ法、細孔分布はｔ−プロット法を用い、分析中に得られる相対圧と吸着容積データセットを使用してＢＪＨ（Barrett, Joyner, Halenda）法で算出した。これら一連のデータはアサップ２４０５（島津製作所）で測定した。
【００２５】
【表２】

【００２６】
上記のように本発明のプロピレンブロック共重合体の製造に用いられる固体触媒は、その特徴として細孔容積が小さく、かつ直径１００Å以上の比較的大きな細孔が少なく、逆に直径１００Å以下の微細な細孔が微分散しているものである。また、その粒子は微細な１次粒子が凝集して２次粒子を形成しており、その１次粒子の平均直径は０．０１〜０．１μm である。
【００２７】
上記のような固体触媒成分はマグネシウム化合物、ハロゲン化チタン化合物および電子供与性化合物を接触させて調製される。マグネシウム化合物としては、二塩化マグネシウムなどのハロゲン化マグネシウムまたはアルコキシマグネシウムが好ましく用いられる。ジアルコキシマグネシウムとしては、ジエトキシマグネシウム、ジプロポキシマグネシウム、ジブトキシマグネシウム、エトキシプロポキシマグネシウム及びブトキシエトキシマグネシウム等が挙げられる。これらの中、二塩化マグネシウムおよびジエトキシマグネシウムが好ましい。さらに、上述した粒子特性を有する固体触媒成分を調製するために、担体となるこれらのマグネシウム化合物においても前述の固体触媒成分の粒子特性とほぼ同等の粒子特性を有することが望ましい。このようなマグネシウム化合物担体は、種々の方法で調製されるが、二塩化マグネシウムあるいはジエトキシマグネシウムの場合、先ず振動ミルやホモジナイザーなどの機械的粉砕または解砕によって微細化し、これをスプレードライなどの方法により凝集させ担体粒子を形成させる。
【００２８】
上記のマグネシウム化合物のうち、特にジエトキシマグネシウムが好ましい。ジエトキシマグネシウムの嵩比重は、０．２０〜０．４０g／ml、より好ましくは０．２３〜０．３７g／ml、特に好ましくは０．２５〜０．３５g／mlの範囲のものを用いることが望ましい。この嵩比重が０．２０g／ml未満であると、嵩比重の高い、高立体規則性のポリオレフィンを高収率で得ることが不可能となる。一方、嵩比重が０．４０g／mlを越えると生成ポリオレフィンの粒子性状に好ましくない影響を与える。ここで嵩比重はＪＩＳ Ｋ６７２１（１９７７）に従って測定したものである。
【００２９】
また、ジエトキシマグネシウムの細孔容積は、０．０１〜０．１ml／gのものが好ましく、より好ましくは０．０１〜０．０６ml／g、さらに好ましくは０．０１５〜０．０５ml／g、の範囲であることが望ましい。このように比較的小さい特定の範囲の細孔容積を有する多孔質のジエトキシマグネシウムを使用し調製した固体触媒成分をオレフィン類の重合に供した際、高立体規則性と優れた粒子性状を有した重合体が高収率で得られ、しかもブロック共重合においては、ゴム状重合体の生成割合が高い場合であっても、優れた粒子性状の共重合体を高収率で得ることが可能となる。
【００３０】
さらに、ジエトキシマグネシウムの細孔容積分布をｌｎ（Ｒ９０／Ｒ１０) （ここでＲ９０は積算細孔容積で９０％のところの細孔半径、Ｒ１０は積算細孔容積で１０％のところの細孔半径を表わす）で示すと、１．５以上であり、好ましくは１．５から３．５の範囲であり、さらに好ましくは２．０から３．０の範囲である。このようにある程度の広い細孔容積分布を有するものが好ましい。ここで、細孔容積分布は窒素ガスの吸着等温線による方法で測定したものである。
【００３１】
さらにまた、ジエトキシマグネシウムの窒素吸着比表面積（Ｎ₂ ＳＡ）は、５〜５０m²／g、好ましくは１０〜４０m²／g、より好ましくは１５〜３０m²／gのものを用いることが望ましく、その形状は球状あるいは楕円球状でさらに狭い粒度分布を有するものを使用することがより好ましい。ここに球状あるいは楕円球状とは、必ずしも顕微鏡観察で表面が平滑な真球あるいは楕円球状である必要はなく、粒子の球形係数として長軸径ｌと短軸径ｗの比（ｌ／ｗ）が３以下であり、好ましくは１〜２であり、より好ましくは１〜１．５のものである。したがって、例えば馬鈴薯のような形状、すなわち表面に凹凸のある粒子形状をしたものも用いることができる。このように球状あるいは楕円球状のジエトキシマグネシウムを用いて得られた固体触媒成分も球状あるいは楕円球状であり、さらにその固体触媒成分を用いて製造されるポリオレフィンも同様の球状あるいは楕円球状になり、結果として非常に流動性に優れた重合体が得られ、ポリオレフィン製造プロセスにおけるメリットとなる。
【００３２】
さらに、ジエトキシマグネシウムの平均粒径は、１〜１００μm 、好ましくは１０〜８０μm 、さらに好ましくは１５〜６０μm であり、その粒度分布は微粉および粗粉の少ない、粒度分布幅の狭いものを使用することが望ましい。具体的には、５μm 以下の粒子が２０重量％以下、好ましくは１５重量％以下、より好ましくは１０重量％以下であり、同時に１００μm 以上の粒子が１０重量％以下、好ましくは５重量％以下のものである。さらに粒度分布を（Ｄ９０−Ｄ１０）／Ｄ５０（ここでＤ９０は積算粒度で９０重量％のところの粒径、Ｄ１０は積算粒度で１０重量％のところの粒径、Ｄ５０は積算粒度で５０重量％のところの粒径を表わす）で示すと、３以下であり、好ましくは２．５、より好ましくは２以下である。このように微粉の少ないジアルコキシマグネシウムを用いることにより、結果として得られるポリオレフィンの微粉を少なくすることが可能となる。
【００３３】
上記のように嵩比重が高く、特定の細孔容積を有する球状あるいは楕円球状で、微粉および粗粉の少ない狭い粒度分布を有するジエトキシマグネシウムは、例えば次に示す方法が好ましく用いられる。すなわち、金属マグネシウムとエタノールを、溶媒の不存在下また触媒の存在下に直接反応させてジエトキシマグネシウムを製造する。この方法において、金属マグネシウムとエタノールの反応系への最終添加割合を金属マグネシウム／エタノール（重量比）＝１／９〜１５／１とし、前記最終添加割合の金属マグネシウムとエタノールを、エタノール反応系に連続的または断続的に添加し、５〜８０分間に亘り反応させ、次いで、エタノールの還流下に１〜３０時間保持し、熟成反応を行う。上記の方法で用いられる金属マグネシウムは例えば、数十〜数百メッシュ、より具体的には１００メッシュ程度の粉末状の反応性の良好なものが好ましい。
【００３４】
また上記触媒としては、例えば、臭化メチル、塩化メチル、臭化エチル、塩化エチルなどのハロゲン化アルキル、塩化マグネシウム、塩化アルミニウムなどの金属ハロゲン化物、ジエトキシマグネシウムなどのジアルコキシマグネシウム、沃素、酢酸エステルなどが使用され、この中でも沃素が好ましく用いられる。
【００３５】
さらに上述した特定の範囲の平均粒径、比表面積、細孔容積及び細孔分布を有する固体触媒成分を調製するためには、上記のようなジエトキシマグネシウムの特性の他、微細な１次粒子がある程度の強さで凝集し２次粒子を形成していることが重要である。１次粒子の大きさとしては０．０１〜０．１μｍである。このようなジエトキシマグネシウムはその調製条件を調整することによって得ることができ、初期の反応速度を上げることにより１次粒子は小さくなる。具体的手段としては金属マグネシウムとエタノールの反応時に存在させる触媒量を多くし、より具体的には沃素などの触媒量を、反応に供する金属マグネシウム１ｇ当り０．１ｇ以上、好ましくは０．１３ｇ以上、特に好ましくは０．１５ｇ以上添加する方法、あるいは金属マグネシウムとエタノールを、エタノール反応系に連続的または断続的に添加する際、添加速度を上げる方法などが挙げられる。
【００３６】
ハロゲン化チタン化合物としては、具体的には、TiCl₄、Ti(OCH₃)Cl₃、
Ti(OC₂H₅)Cl₃、Ti(OC₃H₇)Cl₃、Ti(O-n-C₄H₉)Cl₃、Ti(OCH₃)₂Cl₂、Ti(OC₂H₅)₂Cl₂、Ti(OC₃H₇)₂Cl₂、Ti(O-n-C₄H₉)₂Cl₂ 、Ti(OCH₃)₃Cl 、Ti(OC₂H₅)₃Cl、Ti(OC₃H₇)₃Cl、Ti(O-n-C₄H₉)₃Cl 等が例示され、この中、TiCl₄が好ましく用いられる。これらの四価のハロゲン化チタン化合物は、１種単独又は２種以上組み合わせて用いることもできる。
【００３７】
電子供与性化合物は、酸素原子あるいは窒素原子を含有する有機化合物であり、例えばアルコール類、フェノール類、エーテル類、エステル類、ケトン類、酸ハライド類、アルデヒド類、アミン類、アミド類、ニトリル類、イソシアネート類、Ｓｉ−Ｏ−Ｃ結合を含む有機ケイ素化合物等が挙げられる。具体的には、メタノール、エタノール、ｎ−プロパノール、２−エチルヘキサノール等のアルコール類、フェノール、クレゾール等のフェノール類、メチルエーテル、エチルエーテル、プロピルエーテル、ブチルエーテル、アミルエーテル、ジフェニルエーテル、９，９−ビス（メトキシメチル）フルオレン、２−イソプロピル−２−イソペンチル−１，３―ジメトキシプロパン等のエーテル類、ギ酸メチル、酢酸エチル、酢酸ビニル、酢酸プロピル、酢酸オクチル、酢酸シクロヘキシル、プロピオン酸エチル、酪酸エチル、安息香酸メチル、安息香酸エチル、安息香酸プロピル、安息香酸ブチル、安息香酸オクチル、安息香酸シクロヘキシル、安息香酸フェニル、ｐ−トルイル酸メチル、ｐ−トルイル酸エチル、アニス酸メチル、アニス酸エチル等のモノカルボン酸エステル類、マレイン酸ジエチル、マレイン酸ジブチル、アジピン酸ジメチル、アジピン酸ジエチル、アジピン酸ジプロピル、アジピン酸ジブチル、アジピン酸ジイソデシル、アジピン酸ジオクチル、フタル酸ジエステル等のジカルボン酸エステル類、アセトン、メチルエチルケトン、メチルブチルケトン、アセトフェノン、ベンゾフェノン等のケトン類、フタル酸ジクロライド、テレフタル酸ジクロライド等の酸ハライド類、アセトアルデヒド、プロピオンアルデヒド、オクチルアルデヒド、ベンズアルデヒド等のアルデヒド類、メチルアミン、エチルアミン、トリブチルアミン、ピペリジン、アニリン、ピリジン等のアミン類、オレイン酸アミド、ステアリン酸アミド等のアミド類、アセトニトリル、ベンゾニトリル、トルニトリル等のニトリル類、イソシアン酸メチル、イソシアン酸エチル等のイソシアネート類、フェニルアルコキシシラン、アルキルアルコキシシラン、フェニルアルキルアルコキシシラン、シクロアルキルアルコキシシラン、シクロアルキルアルキルアルコキシシラン等のＳｉ−Ｏ−Ｃ結合を含む有機ケイ素化合物を挙げることができる。
【００３８】
上記の電子供与性化合物のうち、エステル類、とりわけ芳香族ジカルボン酸ジエステルが好ましく用いられ、特に、フタル酸ジエステルが好適である。これらのフタル酸ジエステルの具体例としては、フタル酸ジメチル、フタル酸ジエチル、フタル酸ジ−ｎ−プロピル、フタル酸ジ−ｉｓｏ−プロピル、フタル酸ジ−ｎ−ブチル、フタル酸ジ−ｉｓｏ−ブチル、フタル酸エチルメチル、フタル酸メチル（ｉｓｏ−プロピル）、フタル酸エチル（ｎ−プロピル）、フタル酸エチル（ｎ−ブチル）、フタル酸エチル（ｉｓｏ−ブチル）、フタル酸ジ−ｎ−ペンチル、フタル酸ジ−ｉｓｏ−ペンチル、フタル酸ジ−ｎｅｏ−ペンチル、フタル酸ジヘキシル、フタル酸ジ−ｎ−ヘプチル、フタル酸ジ−ｎ−オクチル、フタル酸ビス（２，２−ジメチルヘキシル）、フタル酸ビス（２−エチルヘキシル）、フタル酸ジ−ｎ−ノニル、フタル酸ジ−ｉｓｏ−デシル、フタル酸ビス（２，２−ジメチルヘプチル）、フタル酸ｎ−ブチル（ｉｓｏ−ヘキシル）、フタル酸ｎ−ブチル（２−エチルヘキシル）、フタル酸ｎ−ペンチルヘキシル、フタル酸ｎ−ペンチル（ｉｓｏ−ヘキシル）、フタル酸ｉｓｏ−ペンチル（ヘプチル）、フタル酸ｎ−ペンチル（２−エチルヘキシル）、フタル酸ｎ−ペンチル（ｉｓｏ−ノニル）、フタル酸ｉｓｏ−ペンチル（ｎ−デシル）、フタル酸ｎ−ペンチルウンデシル、フタル酸ｉｓｏ−ペンチル（ｉｓｏ−ヘキシル）、フタル酸ｎ−ヘキシル（２，２−ジメチルヘキシル）、フタル酸ｎ−ヘキシル（２−エチルヘキシル）、フタル酸ｎ−ヘキシル（ｉｓｏ−ノニル）、フタル酸ｎ−ヘキシル（ｎ−デシル）、フタル酸ｎ−ヘプチル（２−エチルヘキシル）、フタル酸ｎ−ヘプチル（ｉｓｏ−ノニル）、フタル酸ｎ−ヘプチル（ｎｅｏ−デシル）、フタル酸２−エチルヘキシル（ｉｓｏ−ノニル）が例示される。これらの１種あるいは２種以上が使用される。なお、上記のエステル類は、２種以上組み合わせて用いることも好ましく、その際用いられるエステルのアルキル基の炭素数合計が他のエステルのそれと比べ、その差が４以上になるように該エステル類を組み合わせることが望ましい。
【００３９】
更に、これらのフタル酸ジエステルの芳香環に１または２個の炭素数１〜５のアルキル基または塩素、臭素及びフッ素などのハロゲン原子が置換したものも好ましく用いられる。具体的には、４−メチルフタル酸ジネオペンチル、４−エチルフタル酸ジネオペンチル、４，５−ジメチルフタル酸ジネオペンチル、４，５−ジエチルフタル酸ジネオペンチル、４−クロロフタル酸ジエチル、４−クロロフタル酸ジ−ｎ−ブチル、４−クロロフタル酸ジイソブチル、４−クロロフタル酸ジイソヘキシル、４−クロロフタル酸ジイソオクチル、４−ブロモフタル酸ジエチル、４−ブロモフタル酸ジ−ｎ−ブチル、４−ブロモフタル酸ジイソブチル、４−ブロモフタル酸ジイソヘキシル、４−ブロモフタル酸ジイソオクチル、４−ブロモフタル酸ジイソネオペンチル、４，５−ジクロロフタル酸ジエチル、４，５−ジクロロフタル酸ジ−ｎ−ブチル、４，５−ジクロロフタル酸ジイソヘキシル、４，５−ジクロロフタル酸ジイソオクチルが挙げられる。
【００４０】
固体触媒成分は上記マグネシウム化合物、ハロゲン化チタン化合物および電子供与性化合物を接触させることにより調製することができ、この接触は、不活性有機溶媒の不存在下で処理することも可能であるが、操作の容易性を考慮すると、該溶媒の存在下で処理することが好ましい。用いられる不活性有機溶媒としては、ヘキサン、ヘプタン、シクロヘキサン等の飽和炭化水素化合物、ベンゼン、トルエン、キシレン、エチルベンゼン等の芳香族炭化水素化合物、オルトジクロルベンゼン、塩化メチレン、四塩化炭素、ジクロルエタン等のハロゲン化炭化水素化合物等が挙げられるが、このうち、沸点が９０〜１５０℃程度の、常温で液状状態の芳香族炭化水素化合物、具体的にはトルエン、キシレン、エチルベンゼンが好ましく用いられる。各成分の接触は、不活性ガス雰囲気下、水分等を除去した状況下で、撹拌機を具備した容器中で、撹拌しながら行われる。接触温度は、単に接触させて撹拌混合する場合や、分散あるいは懸濁させて変性処理する場合には、室温付近の比較的低温域であっても差し支えないが、接触後に反応させて生成物を得る場合には、４０〜１３０℃の温度域が好ましい。反応時の温度が４０℃未満の場合は充分に反応が進行せず、結果として調製された固体触媒成分の性能が不充分となり、１３０℃を超えると使用した溶媒の蒸発が顕著になるなどして、反応の制御が困難になる。なお、反応時間は１分以上、好ましくは１０分以上、より好ましくは３０分以上である。前記した特有のマグネシウム化合物を担体として用いる場合、その粒子特性を壊さずそのまま維持しながらハロゲン化チタン化合物および電子供与性化合物と接触させ固体触媒成分を調製する必要があり、特にジエトキシマグネシウムを用いる場合、ハロゲン化チタン化合物と接触により急激なハロゲン化反応が進み、粒子が破壊される場合があるので、特に初期段階での接触反応の条件に留意する必要がある。
【００４１】
固体触媒成分の好ましい調製方法としては、以下のような方法が挙げられる。例えば、ジアルコキシマグネシウムをトルエンのごとき常温で液体の芳香族炭化水素化合物に懸濁させることによって懸濁液を形成し、次いでこの懸濁液を四塩化チタン中に、反応系の温度を低温に維持しながら添加する。このときの好ましい温度範囲は−１５〜５℃、より好ましくは−１０〜０℃である。添加終了後さらに低温に保持し熟成反応を行う。このときの好ましい温度範囲も−１５〜５℃、より好ましくは−１０〜０℃である。その後昇温し７０〜１２０℃で反応させる。この際、上記の懸濁液に四塩化チタンを接触させる前又は接触した後に、フタル酸ジエステルなどの電子供与性化合物を、−２０〜１３０℃で接触させ、固体反応生成物を得る。この固体反応生成物を常温で液体の芳香族炭化水素化合物で洗浄した後、再度四塩化チタンを、芳香族炭化水素化合物の存在下に添加し、７０〜１２０℃で接触反応させ、更に常温で液体の炭化水素化合物で洗浄し固体触媒成分を得る。さらに四塩化チタンを繰り返し接触させることも触媒の活性を向上させる上で好ましい態様である。
【００４２】
各化合物の使用量比は、調製法により異なるため一概には規定できないが、例えば、マグネシウム化合物１モル当たり、ハロゲン化チタン化合物が０．５〜１００モル、好ましくは０．５〜５０モル、より好ましくは１〜１０モルであり、電子供与性化合物が０．０１〜１０モル、好ましくは０．０１〜１モル、より好ましくは０．０２〜０．６モルである。
【００４３】
重合用触媒を形成する際に用いられる有機アルミニウム化合物としては、トリエチルアルミニウム、ジエチルアルミニウムクロライド、トリ−ｉｓｏ−ブチルアルミニウム、ジエチルアルミニウムブロマイド、ジエチルアルミニウムハイドライドが挙げられ、１種あるいは２種以上が使用できる。好ましくは、トリエチルアルミニウム、トリ−ｉｓｏ−ブチルアルミニウムである。
【００４４】
重合用触媒を形成する際に用いられる外部電子供与性化合物としては、前述の固体触媒成分を構成する電子供与性化合物と同じものが用いられるが、その中でも、９，９−ビス（メトキシメチル）フルオレン、２−イソプロピル−２−イソペンチル−１，３―ジメトキシプロパン等のエーテル類、安息香酸メチルおよび安息香酸エチルなどのエステル類、及び有機ケイ素化合物が好適である。有機ケイ素化合物としては、一般式R¹ _qSi(OR²)_4-q（式中、R¹は炭素数１〜１２のアルキル基、シクロアルキル基、フェニル基、ビニル基、アリル基、アラルキル基を示し、同一又は異なっていてもよい。R²は炭素数１〜４のアルキル基、シクロアルキル基、フェニル基、ビニル基、アリル基、アラルキル基を示し、同一又は異なっていてもよい。q は０≦q ≦３の整数である。）で表される化合物が用いられる。このような有機ケイ素化合物としては、フェニルアルコキシシラン、アルキルアルコキシシラン、フェニルアルキルアルコキシシラン、シクロアルキルアルコキシシラン、シクロアルキルアルキルアルコキシシラン等を挙げることができる。
【００４５】
上記の有機ケイ素化合物を具体的に例示すると、トリメチルメトキシシラン、トリメチルエトキシシラン、トリ−ｎ−プロピルメトキシシラン、トリ−ｎ−プロピルエトキシシラン、トリ−ｎ−ブチルメトキシシラン、トリ−ｉｓｏ−ブチルメトキシシラン、トリ−ｔ−ブチルメトキシシラン、トリ−ｎ−ブチルエトキシシラン、トリシクロヘキシルメトキシシラン、トリシクロヘキシルエトキシシラン、シクロヘキシルジメチルメトキシシラン、シクロヘキシルジエチルメトキシシラン、シクロヘキシルジエチルエトキシシラン、ジメチルジメトキシシラン、ジメチルジエトキシシラン、ジ−ｎ−プロピルジメトキシシラン、ジ−ｉｓｏ−プロピルジメトキシシラン、ジ−ｎ−プロピルジエトキシシラン、ジ−ｉｓｏ−プロピルジエトキシシラン、ジ−ｎ−ブチルジメトキシシラン、ジ−ｉｓｏ−ブチルジメトキシシラン、ジ−ｔ−ブチルジメトキシシラン、ジ−ｎ−ブチルジエトキシシラン、ｎ−ブチルメチルジメトキシシラン、ビス（２−エチルヘキシル）ジメトキシシラン、ビス（２−エチルヘキシル）ジエトキシシラン、ジシクロペンチルジメトキシシラン、ジシクロペンチルジエトキシシラン、ジシクロヘキシルジメトキシシラン、ジシクロヘキシルジエトキシシラン、ビス（３−メチルシクロヘキシル）ジメトキシシラン、ビス（４−メチルシクロヘキシル）ジメトキシシラン、ビス（３，５−ジメチルシクロヘキシル）ジメトキシシラン、シクロヘキシルシクロペンチルジメトキシシラン、シクロヘキシルシクロペンチルジエトキシシラン、シクロヘキシルシクロペンチルジプロポキシシラン、３−メチルシクロヘキシルシクロペンチルジメトキシシラン、４−メチルシクロヘキシルシクロペンチルジメトキシシラン、３，５−ジメチルシクロヘキシルシクロペンチルジメトキシシラン、３−メチルシクロヘキシルシクロヘキシルジメトキシシラン、４−メチルシクロヘキシルシクロヘキシルジメトキシシラン、３，５−ジメチルシクロヘキシルシクロヘキシルジメトキシシラン、シクロペンチルメチルジメトキシシラン、シクロペンチルメチルジエトキシシラン、シクロペンチルエチルジエトキシシラン、シクロペンチル（ｉｓｏ−プロピル）ジメトキシシラン、シクロペンチル（ｉｓｏ−ブチル）ジメトキシシラン、シクロヘキシルメチルジメトキシシラン、シクロヘキシルメチルジエトキシシラン、シクロヘキシルエチルジメトキシシラン、シクロヘキシルエチルジエトキシシラン、シクロヘキシル（ｎ−プロピル）ジメトキシシラン、シクロヘキシル（ｉｓｏ−プロピル）ジメトキシシラン、シクロヘキシル（ｎ−プロピル）ジエトキシシラン、シクロヘキシル（ｉｓｏ−ブチル）ジメトキシシラン、シクロヘキシル（ｎ−ブチル）ジエトキシシラン、シクロヘキシル（ｎ−ペンチル）ジメトキシシラン、シクロヘキシル（ｎ−ペンチル）ジエトキシシラン、ジフェニルジメトキシシラン、ジフェニルジエトキシシラン、フェニルメチルジメトキシシラン、フェニルメチルジエトキシシラン、フェニルエチルジメトキシシラン、フェニルエチルジエトキシシラン、メチルトリメトキシシラン、メチルトリエトキシシラン、エチルトリメトキシシラン、エチルトリエトキシシラン、ｎ−プロピルトリメトキシシラン、ｉｓｏ−プロピルトリメトキシシラン、ｎ−プロピルトリエトキシシラン、ｉｓｏ−プロピルトリエトキシシラン、ｎ−ブチルトリメトキシシラン、ｉｓｏ−ブチルトリメトキシシラン、ｔ−ブチルトリメトキシシラン、ｎ−ブチルトリエトキシシラン、２−エチルヘキシルトリメトキシシラン、２−エチルヘキシルトリエトキシシラン、シクロペンチルトリメトキシシラン、シクロペンチルトリエトキシシラン、シクロヘキシルトリメトキシシラン、シクロヘキシルトリエトキシシラン、ビニルトリメトキシシラン、ビニルトリエトキシシラン、フェニルトリメトキシシラン、フェニルトリエトキシシラン、テトラメトキシシラン、テトラエトキシシラン、テトラプロポキシシラン、テトラブトキシシラン等を挙げることができる。上記の中でも、ジ−ｎ−プロピルジメトキシシラン、ジ−ｉｓｏ−プロピルジメトキシシラン、ジ−ｎ−ブチルジメトキシシラン、ジ−ｉｓｏ−ブチルジメトキシシラン、ジ−ｔ−ブチルジメトキシシラン、ジ−ｎ−ブチルジエトキシシラン、ｔ−ブチルトリメトキシシラン、ジシクロヘキシルジメトキシシラン、ジシクロヘキシルジエトキシシラン、シクロヘキシルメチルジメトキシシラン、シクロヘキシルメチルジエトキシシラン、シクロヘキシルエチルジメトキシシラン、シクロヘキシルエチルジエトキシシラン、ジシクロペンチルジメトキシシラン、ジシクロペンチルジエトキシシラン、シクロペンチルメチルジメトキシシラン、シクロペンチルメチルジエトキシシラン、シクロペンチルエチルジエトキシシラン、シクロヘキシルシクロペンチルジメトキシシラン、シクロヘキシルシクロペンチルジエトキシシラン、３−メチルシクロヘキシルシクロペンチルジメトキシシラン、４−メチルシクロヘキシルシクロペンチルジメトキシシラン、３，５−ジメチルシクロヘキシルシクロペンチルジメトキシシランが好ましく用いられ、該有機ケイ素化合物は１種単独あるいは２種以上組み合わせて用いることができる。
【００４６】
固体触媒成分、有機アルミニウム化合物、および外部電子供与性化合物の使用量比は、本発明の効果に影響を及ぼすことのない限り任意であり、特に限定されるものではないが、通常、有機アルミニウム化合物は固体触媒成分中のチタン原子１モル当たり、１〜２０００モル、好ましくは５０〜１０００モルの範囲で用いられる。外部電子供与性化合物は、有機アルミニウム化合物１モル当たり、０．００２〜１０モル、好ましくは０．０１〜２モル、特に好ましくは０．０１〜０．５モルの範囲で用いられる。
【００４７】
各成分の接触順序は任意であるが、重合系内にまず有機アルミニウム化合物を装入し、次いで、外部電子供与性化合物を接触させ、更に固体触媒成分を接触させることが望ましい。
【００４８】
更に、上記触媒を用いて本発明のプロピレンブロック共重合体を製造するにあたり、触媒活性、立体規則性及び生成する重合体の粒子性状等を一層改善させるために、本重合に先立ち予備重合を行うことが望ましい。予備重合の際には、本重合と同様のオレフィン類あるいはスチレン等のモノマーを用いることができる。予備重合を行うに際して、各成分及びモノマーの接触順序は任意であるが、好ましくは、不活性ガス雰囲気あるいはプロピレンなどの重合を行うガス雰囲気に設定した予備重合系内にまず有機アルミニウム化合物を装入し、次いで固体触媒成分を接触させた後、プロピレン等のオレフィン及び／または１種あるいは２種以上の他のオレフィン類を接触させる。外部電子供与性化合物を組み合わせて予備重合を行う場合は、不活性ガス雰囲気あるいはプロピレンなどの重合を行うガス雰囲気に設定した予備重合系内にまず有機アルミニウム化合物を装入し、次いで外部電子供与性化合物を接触させ、更に固体触媒成分を接触させた後、プロピレン等のオレフィン及び／または１種あるいはその他の２種以上のオレフィン類を接触させる方法が望ましい。
【００４９】
【実施例】
次に、本発明の実施例を比較例と対比しつつ、具体的に説明する。なお、重合体の各特性は以下の方法により評価した。
【００５０】
（メルトインデックス（メルトフローレート）の値（ＭＦＲ））
ＡＳＴＭ Ｄ１２３８の方法に準じて測定した。
【００５１】
（曲げ弾性率）
重合体に耐熱安定剤を配合した後、押出機でペレット化し、これを射出成形機により成型して測定試料を作成し、ＡＳＴＭ Ｄ７９０に従って２３℃で測定した。
【００５２】
（アイゾット衝撃強度）
重合体に耐熱安定剤を配合した後、押出機でペレット化し、これを射出成形機により成型して測定試料を作成し、ＡＳＴＭ Ｄ２５６に従ってノッチ付き射出成形試験片について、２３℃で測定した。
【００５３】
（プロピレンブロック共重合体の組成）
ゴム部割合（ブロック率）、表面上のゴム部割合、ＰＰ部セクションの平均直径、ゴム部セクションの平均直径、ゴム部セクション直径累積分布９０％及びＤpp／Ｄr は、透過型電子顕微鏡（Ｈ−７１００ＦＡ型；日立製作所社製）及び画像処理装置（ＬＵＺＥＸ Ｆ型；ニレコ社製）を使用して解析した。また、ＭＦＲはＡＳＴＭ Ｄ１２３８の方法に準じて測定した。また、ＰＰ部キシレン不溶分は以下の方法で求めた。４．０g のポリマーを２００mlのパラキシレンに装入し、沸点下（１３８℃）で２時間かけてポリマーを溶解した。その後２３℃まで冷却し、溶解成分と不溶解成分とをろ過分別した。その溶解成分を加熱乾燥し、得られたポリマーをキシレン溶解成分(XS)とした（重量％）。
【００５４】
（エチレン含有量、ＥＰＲ含有量）
プロピレンブロック共重合体中のエチレン含有量は、¹³Ｃ−ＮＭＲにより定量した。また、プロピレンブロック共重合体中のエチレンプロピレンゴム成分（ＥＰＲ） の含有量を以下の方法により測定した。攪拌機および冷却管を具備した１リッターのフラスコに、共重合体を約２．５g 、２，６−ジ−ｔ−ブチル−ｐ−クレゾール８mg、ｐ−キシレン２５０mlを投入し、沸点下で、共重合体が完全に溶解するまで攪拌した。次に、フラスコを室温まで冷却し、１５時間放置し、固形物を析出させた。これを遠心分離機により固形物と液相部分とに分離した。その後分離した固形物をビーカーにとり、アセトン５００mlを流入し、室温で１５時間攪拌した後、固形物を濾過乾燥させ、重量を測定した（この重量をＢとする）。また分離した液相部分も同様の操作を行い、固形物を析出させ重量を測定した（この重量をＣ とする）。共重合体中のエチレンプロピレンゴム成分（ＥＰＲ） の含有量（重量％）は、〔Ｃ(g)/[Ｂ(g)+Ｃ(g)]×100 〕式により算出した。
【００５５】
（プロピレンブロック共重合体の流動性）
図３に示すように出口位置にダンパー２を介設した漏斗１（上部口径；91mm、ダンパー位置口径；８mm、傾斜角；20°、ダンパー位置までの高さ；114mm ）を上部にセットし、前記ダンパー２の下部に３８mmの間隔を置いて容器状の受器３（内径；40mm、高さ；81mm）を設置した装置を用い、先ず上部の漏斗１に重合体５０g を投入した後、ダンパー２を開口して重合体を受器３に落下させ、全ての重合体が落下する時間を計測した。この操作をプロピレンブロック共重合体およびこのプロピレンブロック共重合体の重合に使用したものと同じ固体触媒成分を使用して重合したプロピレン単独重合体（実施例１の重プロピレンブロック共重合体の製造においてプロピレンの重合反応のみを実施して得られた重合体）について行い、落下時間をそれぞれＴ１およびＴ２とし、Ｔ１／Ｔ２で求めた値を流動性として示した。
【００５６】
実施例１
（ジエトキシマグネシウムの調製）
エタノール１０００ml中にヨウ素１００ｇを溶解して加熱し沸騰還流させた。この中に金属マグネシウムとエタノールのスラリーを連続的に２時間かけて添加して、金属マグネシウムを合計５００ｇ添加し還流下で反応させた。この時、エタノールの量は７．６ｌであった。その後、３時間熟成反応させ、得られた固形物をエタノールで洗浄し、乾燥してジエトキシマグネシウム粉末を得た。このジエトキシマグネシウムを分析したところ、嵩比重０．３１g／ml、比表面積（Ｎ₂ ＳＡ）１９．８m²／g、球形度（ｌ／ｗ）１．１０、平均粒径２５μm 、細孔容積０．０２ml／g、細孔分布〔ｌｎ（Ｒ９０／Ｒ１０）〕２．３０、５μm 以下の微粉含有率５％、粒度分布〔（Ｄ９０−Ｄ１０）／Ｄ５０〕 １．０５であった。
【００５７】
（固体触媒成分の調製）
攪拌機を具備し窒素ガスで充分に置換された容量２０００mlの丸底フラスコに、前記ジエトキシマグネシウム１５０g 、トルエン７５０ml及び及びフタル酸ジ−ｎ−ブチル５４mlを装入し、懸濁状態とした。次いで、該懸濁溶液を、攪拌機を具備し窒素ガスで充分に置換された容量３０００mlの丸底フラスコ中に予め装入されたトルエン４５０ml及び四塩化チタン３００mlの溶液中に１時間かけて連続的に添加した。その際、反応系の温度を−５℃に保持した。上記混合溶液を−５℃に保持したまま１時間攪拌し、その後、１００℃まで４時間かけて昇温し、攪拌しながら２時間反応させた。次いで、反応終了後、生成物を８０℃の温度を維持して攪拌しながら２時間接触反応させた。次いで、生成物を４０℃のヘプタンで７回洗浄し、濾過、乾燥して粉末状の固体触媒成分を得た。この固体触媒成分中のチタン含有量を測定したところ、３．１５重量％であった。該固体触媒成分の平均粒径、比表面積、細孔容積及び細孔分布を測定した。結果を表３に示す。
【００５８】
（プロピレンブロック共重合体の製造）
窒素ガスで完全に置換された内容積２．０リットルの撹拌機付オートクレーブに、トリエチルアルミニウム（ＴＥＡＬ）、シクロヘキシルメチルジメトキシシラン（ＣＭＤＭＳ）および前記固体触媒成分をチタン原子として０．００２６ｍｍｏｌ装入し、重合用触媒を形成した。このとき固体触媒成分中のＴｉ、ＴＥＡＬおよびＣＭＤＭＳのモル比（Ｔｉ／ＴＥＡＬ／ＣＭＤＭＳ）は、１／４００／６７とした。その後、水素ガス２．０リットル、液化プロピレン１．２リットルを装入し、７０℃で１時間プロピレン重合反応を行い、ＰＰ部割合が約７０重量％になるように重合反応を行った。その後、エチレンガスおよびプロピレンガスをエチレン／プロピレンモル比０．７で供給しながら、１．７ＭＰａの圧力で気相で７０℃で２時間重合を行い、ゴム部割合が約３０重量％になるように、プロピレンブロック共重合体を製造した。得られたプロピレンブロック共重合体のＴＥＭ（透過型電子顕微鏡）写真を図１に、ゴム部割合（ブロック率）、表面上のゴム部割合、エチレン含有量、ＥＰＲ含有量、ＰＰ部ＭＦＲ、ＰＰ部キシレン不溶分、ＰＰ部セクションの平均直径、ゴム部セクションの平均直径、ゴム部セクション直径累積分布９０％、Ｄpp／Ｄr 、ＭＩ、曲げ弾性率及びアイゾット衝撃強度を表３にそれぞれ示す。なお、ＰＰ部のＭＦＲ及びＰＰ部のキシレン不溶分は、上記プロピレン重合反応後の、反応生成物を測定したものである。
【００５９】
実施例２
（プロピレンブロック共重合体の製造）
ゴム部割合を６３．５重量％とするために、７０℃で０．５時間プロピレン重合を行い、７０℃で２時間エチレンプロピレン共重合を行ってプロピレンブロック共重合体を製造した以外は、実施例１と同様に方法で行った。得られたプロピレンブロック共重合体のＴＥＭ（透過型電子顕微鏡）写真を図２に、実施例１と同様の特性値を表３にそれぞれ示す。
【００６０】
実施例３
（ジエトキシマグネシウムの調製）
エタノール１０００ml中にヨウ素１００ｇを溶解して加熱し沸騰還流させた。この中に金属マグネシウムとエタノールのスラリーを連続的に１時間かけて添加して、金属マグネシウムを合計５００ｇ添加し還流下で反応させた。この時、エタノールの量は７．６ｌであった。その後、３時間熟成反応させ、得られた固形物をエタノールで洗浄し、乾燥してジエトキシマグネシウム粉末を得た。このジエトキシマグネシウムを分析したところ、嵩比重０．３０g／ml、比表面積（Ｎ₂ ＳＡ）２０．５m²／g、球形度（ｌ／ｗ）１．０５、平均粒径２４μm 、細孔容積０．０１８ml／g、細孔分布〔ｌｎ（Ｒ９０／Ｒ１０）〕２．１０、５μm 以下の微粉含有率５％、粒度分布〔（Ｄ９０−Ｄ１０）／Ｄ５０〕 １．０５であった。
【００６１】
（固体触媒成分の調製及びプロピレンブロック共重合体の製造）
上記で得られたジエトキシマグネシウムを用いた以外は実施例１と同様に固体触媒成分の調製及びプロピレンブロック共重合体の製造を行った。得られた結果を表３に示す。
【００６２】
実施例４
（固体触媒成分の調製）
攪拌機を具備し窒素ガスで充分に置換された容量２０００mlの丸底フラスコに、実施例１で調製したジエトキシマグネシウム１５０g 、トルエン７５０ml及び及びフタル酸ジ−ｎ−ブチル５４mlを装入し、懸濁状態とした。次いで、該懸濁溶液を、攪拌機を具備し窒素ガスで充分に置換された容量３０００mlの丸底フラスコ中に予め装入されたトルエン４５０ml及び四塩化チタン３００mlの溶液中に１時間かけて連続的に添加した。その際、反応系の温度を−８℃に保持した。上記混合溶液を−８℃に保持したまま１時間攪拌し、その後、１００℃まで４時間かけて昇温し、攪拌しながら２時間反応させた。次いで、反応終了後、生成物を８０℃の温度を維持して攪拌しながら２時間接触反応させた。次いで、生成物を４０℃のヘプタンで７回洗浄し、濾過、乾燥して粉末状の固体触媒成分を得た。この固体触媒成分中のチタン含有量を測定したところ、３．１５重量％であった。該固体触媒成分の平均粒径、比表面積、細孔容積及び細孔分布を測定した。結果を表３に示す。
【００６３】
（プロピレンブロック共重合体の製造）
上記で得られた固体触媒成分を用いた以外は実施例１と同様にプロピレンブロック共重合体の製造を行った。得られた結果を表３に示す。
【００６４】
比較例１
（ジエトキシマグネシウムの調製）
市販のヒュルス社製顆粒状ジエトキシマグネシウム（品名：マグネシウムエチラート、粒径５００〜１５００μｍ）１ｋｇを窒素ガスで置換した内容積約１０リッターのボールミルに装入して５分間粉砕した。得られたジエトキシマグネシウムの物性を測定した結果、ＪＩＳ Ｋ６７２１に従って測定した嵩比重が０．４１ｇ／ｍｌ、比表面積（Ｎ₂ＳＡ）が９．８ｍ²／ｇ、球形度（ｌ／ｗ）が２．０、平均粒径が１０１．９μｍ、細孔容積が０．０１０ｍｌ／ｇ、細孔分布［ｌｎ（Ｄ９０／Ｄ１０）］が２．６３、５μｍ以下の微粉含有率が４．１％、粒度分布［（Ｄ９０−Ｄ１０）／Ｄ５０］が２．４４であった。
【００６５】
（固体触媒成分の調製）
攪拌機を具備し窒素ガスで充分に置換された容量２０００mlの丸底フラスコに、上記の顆粒状のジエトキシマグネシウム１５０g 、トルエン７５０ml及びフタル酸ジ−ｎ−ブチル５４mlを装入し、懸濁状態とした。次いで、該懸濁溶液を、攪拌機を具備し窒素ガスで充分に置換された容量３０００mlの丸底フラスコ中に予め装入されたトルエン４５０ml及び四塩化チタン３００mlの溶液中に１時間かけて連続的に添加した。その際、反応系の温度を５℃に保持した。その後、１００℃まで４時間かけて昇温し、攪拌しながら２時間反応させた。次いで、反応終了後、生成物を８０℃の温度を維持して攪拌しながら２時間接触反応させた。次いで、生成物を４０℃のヘプタンで７回洗浄し、濾過、乾燥して粉末状の固体触媒成分を得た。この固体触媒成分中のチタン含有量を測定したところ、３．１５重量％であった。該固体触媒成分の平均粒径、比表面積、細孔容積及び細孔分布を測定した。結果を表３に示す。
【００６６】
（プロピレンブロック共重合体の製造）
実施例１と同様に実験を行い、プロピレンブロック共重合体を得た。得られたプロピレンブロック共重合体の特性値を表３に示す。
【００６７】
比較例２
（固体触媒成分の調製）
二塩化マグネシウム９５．２ｇ、デカン４４２ml及び２−エチルヘキシルアルコール３９０．６ｇを１３０℃で２時間加熱反応を行って均一溶液とした後、この溶液に無水フタル酸２１．３ｇを添加し、更に、１３０℃で１時間攪拌混合を行い、無水フタル酸を溶解させ均一溶液を得た。室温に冷却した後、四塩化チタン２００ml中に、この均一溶液の７５mlを滴下し、その後、１１０℃に昇温し、１１０℃に達したところでフタル酸ジイソブチル５．２２ｇを添加し、２時間攪拌しながら反応させた。反応終了後、生成物を２７５mlの四塩化チタンに再懸濁させた後、１１０℃で２時間処理した。次いで、生成物を４０℃のヘプタンで７回洗浄し、濾過、乾燥して粉末状の固体触媒成分を得た。この固体触媒成分中のチタン含有量を測定したところ、２．８０重量％であった。該固体触媒成分の平均粒径、比表面積、細孔容積及び細孔分布を測定した。結果を表３に示す。
【００６８】
（プロピレンブロック共重合体の製造）
７０℃で１時間プロピレン重合を行い、７０℃で１時間エチレンプロピレン共重合を行ってプロピレンブロック共重合体を製造した以外は、実施例１と同様に実験を行い、プロピレンブロック共重合体を得た。得られたプロピレンブロック共重合体の特性値を表３にそれぞれ示す。
【００６９】
比較例３
（ジエトキシマグネシウムの調製）
エタノール１０００ml中にヨウ素１０ｇを溶解して加熱し沸騰還流させた。この中に金属マグネシウムとエタノールのスラリーを連続的に２時間かけて添加して、金属マグネシウムを合計５００ｇ添加し還流下で反応させた。この時、エタノールの量は７．６ｌであった。その後、３時間熟成反応させ、得られた固形物をエタノールで洗浄し、乾燥してジエトキシマグネシウム粉末を得た。このジエトキシマグネシウムを分析したところ、嵩比重０．２６g／ml、比表面積（Ｎ₂ ＳＡ）１９．８m²／g、球形度（ｌ／ｗ）１．１０、平均粒径３１μm 、細孔容積０．０３ml／g、細孔分布〔ｌｎ（Ｒ９０／Ｒ１０）〕２．３０、５μm 以下の微粉含有率５％、粒度分布〔（Ｄ９０−Ｄ１０）／Ｄ５０〕 １．０５であった。
【００７０】
（固体触媒成分の調製）
攪拌機を具備し窒素ガスで充分に置換された容量２０００mlの丸底フラスコに、前記ジエトキシマグネシウム１５０g 、トルエン７５０ml及び及びフタル酸ジ−ｎ−ブチル５４mlを装入し、懸濁状態とした。次いで、該懸濁溶液を、攪拌機を具備し窒素ガスで充分に置換された容量３０００mlの丸底フラスコ中に予め装入されたトルエン４５０ml及び四塩化チタン３００mlの溶液中に１時間かけて連続的に添加した。その際、反応系の温度を１０℃に保持した。上記混合溶液を１０℃に保持したまま１時間攪拌し、その後、１００℃まで４時間かけて昇温し、攪拌しながら２時間反応させた。次いで、反応終了後、生成物を８０℃の温度を維持して攪拌しながら２時間接触反応させた。次いで、生成物を４０℃のヘプタンで７回洗浄し、濾過、乾燥して粉末状の固体触媒成分を得た。この固体触媒成分中のチタン含有量を測定したところ、２．７０重量％であった。該固体触媒成分の平均粒径、比表面積、細孔容積及び細孔分布を測定した。結果を表３に示す。
【００７１】
（プロピレンブロック共重合体の製造）
上記のようにして得られた固体触媒成分を用いた以外は実施例１と同様に共重合体の製造を行った。得られた結果を表３に示す。
【００７２】
【表３】

【００７３】
【発明の効果】
本発明のプロピレンブロック共重合体は、プロピレン重合体中にゴム成分であるエチレン−プロピレン共重合体を高比率で、且つ高分散に配合できる新規な構造を有する。更に、粒子表面上のゴム比率が少なく、重合体粒子間の付着や装置内壁への付着等が生じることがないため、安定した高品質のブロック共重合体の製造を可能にする。また、このような特有な構造を有することから、剛性および耐衝撃性の両方の性能においてバランスがよく、特に、バンパーなどの自動車部品や家電部品などの用途に非常に有用である。
【図面の簡単な説明】
【図１】実施例１のプロピレンブロック共重合体の断面のＴＥＭ（透過型電子顕微鏡）写真である。
【図２】実施例２のプロピレンブロック共重合体の断面のＴＥＭ（透過型電子顕微鏡）写真である。
【図３】プロピレンブロック共重合体の流動性を測定する装置の図面である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a block copolymer comprising a propylene polymer and an ethylene-propylene copolymer, and in particular, even when the ratio of the ethylene-propylene copolymer as a rubber component is high, the propylene polymer is highly dispersed. In addition, the present invention relates to a propylene block copolymer having no impact on polymer particles and having good impact resistance since there are few rubber components on the surface.
[0002]
[Prior art]
While isotactic polypropylene has excellent properties in rigidity and heat resistance, it has a problem of poor impact resistance. In order to improve the impact resistance while maintaining the rigidity of this polypropylene, various techniques have been developed to blend crystalline polypropylene with ethylene-propylene rubber by a polymer blend to obtain a resin composition. However, with this polymer blend technology, it is difficult to disperse different polymers to a high level at the micro level, and as a result, it is difficult to prepare a resin composition with well-balanced characteristics that maintain high rigidity and impact resistance. Met. In addition, the polymer blend requires a step of blending and kneading different types of polymers, and the cost is very high, and there are some in which the production cost is more than double that of a normal propylene polymer.
[0003]
On the other hand, as a method for improving the problems of such polymer blends, a chemical blend method in which propylene and ethylene or other olefins are polymerized stepwise to form a block copolymer has been studied for a long time. In general, block copolymers by chemical blends are produced by two-stage or multistage polymerization, and are usually produced by first polymerizing propylene and then copolymerizing ethylene with propylene or other olefins. At this time, in order to improve impact resistance, the ratio of the rubber-like polymer produced by copolymerization of ethylene and propylene is increased, but the produced rubber component is deposited on the surface of the polymer particles. As a result, adhesion between the polymer particles and adhesion of the polymer to the inner wall of the apparatus occur. For this reason, it becomes difficult to produce a block copolymer that is stable over the long term.
[0004]
The propylene block copolymer is one in which an ethylene-propylene copolymer is dispersed in a propylene polymer section (or matrix), but in the conventional one, an ethylene-propylene copolymer particle (or section) is very much. Therefore, as described above, the polymer particles are deposited on the surface of the polymer particles, and especially after the copolymer is crystallized, the ethylene-propylene copolymer block particles grow and become larger, and the block copolymer weight dispersed in the micro is highly dispersed. It was difficult to unite, and as a result, there was a problem that the impact resistance was not improved in spite of increasing the content ratio of the rubber component. Thus, the conventional propylene block copolymer has not yet improved the impact resistance significantly.
[0005]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a propylene block copolymer having a novel structure in which an ethylene-propylene copolymer which is a rubber component in a propylene polymer is highly dispersed even at a very high rubber component ratio. Furthermore, the present invention provides a propylene block copolymer having extremely low adhesion of polymer particles and extremely good impact resistance.
[0006]
[Means for Solving the Problems]
In such a situation, the present inventors have intensively studied, and as a result, if a specific solid catalyst component is used, propylene is polymerized, and then ethylene and propylene are copolymerized, the propylene polymer is a rubber component. An ethylene-propylene copolymer can be blended at a high ratio and in a high dispersion, and a propylene block copolymer having a novel structure excellent in impact resistance can be obtained. We found that the ratio of rubber on the surface is small and that it is possible to produce a stable and high-quality block copolymer without causing adhesion between polymer particles or adhesion to the inner wall of the device. It came to do.
[0007]
That is, the present invention is a propylene block copolymer comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer. When the propylene copolymer section is finely dispersed and the irregular-shaped ethylene-propylene copolymer section is converted into a circle having the same area, the average diameter (Dr) of the ethylene-propylene copolymer section is The following formula (1);
Dr (μm) ≦ 0.005 × A (1)
(Wherein A represents the content (% by weight) of the ethylene-propylene copolymer in the propylene block polymer, and 20 ≦ A (% by weight) ≦ 80). A block copolymer is provided.
[0008]
Further, it is a propylene block copolymer comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer, and the propylene polymer and the ethylene-propylene copolymer are complex with each other. Are mixed together to form a propylene polymer section and an ethylene-propylene copolymer section, both of which are indefinite shapes, and when the ethylene-propylene copolymer section is converted into a circle of the same area, the ethylene- The average diameter of the propylene copolymer section (Dr) is the following formula (1);
Dr (μm) ≦ 0.005 × A (1)
(Wherein, A is as defined above) is provided to provide a propylene block copolymer.
[0009]
Further, the present invention is a propylene block copolymer of a particulate material having an average particle size of 100 to 5000 μm, comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer. The ratio of the ethylene-propylene copolymer on the particle surface is 0.3 area% or less of the entire ethylene-propylene block copolymer, to provide a propylene block copolymer.
[0010]
Further, the present invention is obtained by polymerizing propylene and then copolymerizing ethylene and propylene, or contains magnesium, titanium and halogen atoms, has an average particle diameter of 1 to 100 μm and a specific surface area of 100 to 100. 500m²/ G, a polymerization catalyst comprising a solid catalyst component having a pore distribution with a pore volume of less than 0.2 ml / g and a pore diameter of 100% or less and a cumulative pore volume of 50% or more, The propylene block copolymer obtained by polymerizing propylene and then copolymerizing ethylene and propylene is provided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The propylene block copolymer of the present invention comprises a propylene polymer (hereinafter also referred to as “PP part”) 20 to 80% by weight, preferably 30 to 70% by weight, and an ethylene-propylene copolymer (hereinafter referred to as “rubber”). Part). A block copolymer comprising 20 to 80% by weight, preferably 30 to 70% by weight, wherein the propylene polymer has an amorphous ethylene-propylene copolymer section (hereinafter referred to as “parts”). The rubber section is also finely dispersed, in other words, the propylene polymer and the ethylene-propylene copolymer are mixed and mixed together, and the propylene polymer section and the ethylene are both indefinite shape. -A propylene copolymer section (hereinafter also referred to as "PP section") is formed, and the rubber section has the same area. When converted to, the average diameter of the rubber portion section (Dr) satisfies the above equation (1), preferably the following equation (4);
0.02 ≦ Dr (μm) ≦ 0.0045 × A (4)
(Wherein A is as defined above), more preferably the following formula (5);
0.02 ≦ Dr (μm) ≦ 0.004 × A (5)
(In the formula, A is as defined above).
[0012]
In the propylene block copolymer of the present invention, the particle diameter (Dr90) at 90% of the cumulative particle size distribution of the diameter of the ethylene-propylene copolymer section is represented by the following formula (3):
Dr90 (μm) ≦ 0.01 × A (3)
(Wherein A is as defined above), preferably the following formula (6);
0.05 ≦ Dr90 (μm) ≦ 0.01 × A (6) (wherein A is as defined above).
[0013]
FIGS. 1 and 2 are cross-sectional TEM (transmission electron microscope) photographs of the propylene block copolymer of the present invention. FIG. 1 shows PP part 72.1 wt% and rubber part 27.9 wt%. The PP part is 36.5% by weight and the rubber part is 63.5% by weight. As described above, the propylene block copolymer of the present invention is a PP portion (white portion) in which an irregularly shaped rubber portion section (black portion) having a very small size is finely dispersed or highly dispersed, or The PP part and the rubber part are mixed and mixed with each other. When there is a lot of PP part, the rubber part gets into the cracked and island-like parts of the PP part that becomes the matrix phase. When the rubber section is observed in a dispersed state and the rubber section is mixed, it is as if the rubber section is in the matrix phase, and the PP section enters the cracked or island-shaped section of the section. Observed in a dispersed state. Further, when the blending ratio of the PP part and the rubber part is 30 to 70% by weight: 70 to 30% by weight, both are indistinguishable from the matrix phase and the disperse phase, and are indefinitely shaped fines. Are mixed (see FIGS. 1 and 2).
[0014]
In the present invention, the rubber section is one unit of an irregularly shaped rubber part, such as particles or threads, finely dispersed in the PP part. The independent part is defined as one unit, and a plurality of sections are provided. When it is continuous, the portion whose minimum width is less than 0.01 μm is regarded as a PP portion and is one unit. The average diameter was calculated by image-analyzing a TEM photograph of a cross section of the copolymer, obtaining the area of each rubber section, and converting it to a diameter of a circle equal to the area.
[0015]
The rubber part may contain a crystalline ethylene polymer. When the rubber part is composed of a crystalline ethylene polymer and an ethylene-propylene copolymer rubber, the crystalline ethylene polymer is 1 to 80% by weight, preferably 10 to 50% by weight, ethylene-propylene copolymer in the rubber part. The combined rubber is the balance.
[0016]
Furthermore, in the propylene block copolymer of the present invention, the average diameter (Dpp) of the propylene polymer section (hereinafter also referred to as PP section) is represented by the following formula (2):
5.0 ≧ Dpp ≧ e^-0.02×^A   (2)
(Wherein, A is as defined above). In the present invention, the PP part section is a unit of particles in which an irregularly shaped rubber part such as a particle or thread exists in the periphery thereof, and an independent one is a unit, and a plurality of sections are included. If it is continuous, the portion with a minimum width of less than 0.2 μm is regarded as a rubber part and is taken as one unit. The average diameter was calculated by analyzing the image of a TEM photograph of the polymer cross section, obtaining the area of each PP section, and converting it to the diameter of a circle equal to the area.
[0017]
As described above, in the present invention, the average diameter of the PP part section, which is the PP part particle, becomes smaller as the ratio (block ratio) of the rubber part increases, and the structure is basically different. That is, the PP part of the conventional propylene block copolymer is not regarded as a PP part section, and is basically a continuous matrix state, and has a structure in which a rubber part is present in pores inside the PP part. there were. However, the propylene block copolymer of the present invention forms a PP part section having a very small average diameter (or volume) of one unit, particularly when the rubber part ratio exceeds 50% by weight, and has a diameter around or inside thereof. It has a structure in which a very small particle-like or thread-like irregular rubber part exists.
[0018]
In the propylene block copolymer of the present invention, the average diameter of the PP section is 0.5 to 20 times, preferably 1.0 to 15 times, particularly preferably 3.0 to 12 times the average diameter of the rubber section. It is. The average diameter of the PP section varies depending on the ratio of the rubber section in the propylene block copolymer. The higher the ratio of the rubber section, the smaller the average diameter of the PP section. Conversely, the average diameter of the rubber section is growing. That is, as the proportion of the rubber part increases, the PP part particles are subdivided. As described above, since the rubber part can be finely dispersed in the PP part, the proportion of the rubber part in the copolymer can be 50% or more. The rubber part on the surface of the coalesced particles does not precipitate, the polymer particles do not adhere, and the fluidity is maintained.
[0019]
Table 2 shows preferable characteristics of the propylene block copolymer of the present invention. In Table 1, “MFR” indicates the melt flow rate value, and “(η)” indicates the intrinsic viscosity.
[0020]
[Table 1]

[0021]
The propylene block copolymer of the present invention is a particulate material having an average particle size of 100 to 5000 μm, and the ethylene-propylene copolymer deposited on the particle surface is the entire ethylene-propylene copolymer. 0.3 volume% or less of the coalescence, preferably 0.2 volume% or less, particularly preferably 0.1 volume% or less, and has a feature that the rubber part existing on the surface of the copolymer particles is very small. . In the conventional propylene block copolymer or the production method thereof, when the ratio of the rubber part is low, a rubber part is formed inside the polymer particle or inside the PP part matrix, and is deposited on the surface of the polymer particle. However, when the ratio of the rubber part is high, the PP part is cracked and the rubber part is deposited on the polymer surface. Therefore, the polymer particles showed adhesion, and as a result, the polymer particles adhered to each other and aggregated, or adhered to the inner wall of the reaction vessel or the inner wall of the transfer pipe, causing trouble. In the propylene block copolymer of the present invention, even when the ratio of the rubber part is as high as 50% by weight or more, there is almost no rubber part on the surface of the polymer particles, and adhesion is hardly seen. The ratio of the rubber part deposited on the particle surface is determined by image analysis of a cross-sectional photograph of the polymer using a TEM (transmission electron microscope). The area of the rubber part deposited on the particle surface and the total rubber part Calculated by converting from area to capacity.
[0022]
Next, the manufacturing method of the propylene block copolymer of this invention is demonstrated. The propylene block copolymer of the present invention is carried out by multistage polymerization of two or more stages, usually propylene is polymerized in the presence of a polymerization catalyst in the first stage, and ethylene and propylene are copolymerized in the second stage. Is obtained. An α-olefin other than propylene can be coexisted or polymerized alone during the second stage or subsequent polymerization. Examples of α-olefins include ethylene, 1-butene, 4-methyl-1-pentene, vinylcyclohexane, 1-hexene, 1-octene and the like. Specifically, polymerization is carried out by adjusting the polymerization temperature and time so that the PP part ratio is 20 to 80% by weight in the first stage, and then ethylene and propylene or other α-olefins in the second stage. To polymerize the rubber part ratio to 20 to 80% by weight. The polymerization temperatures in the first and second stages are both 200 ° C. or less, preferably 100 ° C. or less, and the polymerization pressure is 10 MPa or less, preferably 5 MPa or less. In the case of polymerization time in each polymerization stage or continuous polymerization, the residence time is usually 1 minute to 5 hours. Examples of the polymerization method include a slurry polymerization method using an inert hydrocarbon solvent such as cyclohexane and heptane, a bulk polymerization method using a solvent such as liquefied propylene, and a gas phase polymerization method using substantially no solvent. . Preferred polymerization methods are bulk polymerization and gas phase polymerization.
[0023]
The polymerization catalyst used in the production of the propylene block copolymer of the present invention includes a solid catalyst component containing magnesium, titanium, halogen and an electron donating compound, an organoaluminum compound, and, if necessary, an external electron donating property. A catalyst combining the compounds is used.
[0024]
The novel and unique structure of the propylene block copolymer of the present invention as described above is mainly attributable to the structure of the solid catalyst component used in the polymerization, and has the particle characteristics as shown in Table 2, A solid catalyst component containing titanium, halogen and an electron donating compound is used. Specific surface area and pore volume were calculated by BET method, pore distribution was calculated by BJH (Barrett, Joyner, Halenda) method using t-plot method and relative pressure and adsorption volume data set obtained during analysis. These series of data were measured with Asap 2405 (Shimadzu Corporation).
[0025]
[Table 2]

[0026]
As described above, the solid catalyst used in the production of the propylene block copolymer of the present invention is characterized by small pore volume, few relatively large pores having a diameter of 100 mm or more, and conversely, a fine catalyst having a diameter of 100 mm or less. Fine pores are finely dispersed. In addition, fine primary particles aggregate to form secondary particles, and the average diameter of the primary particles is 0.01 to 0.1 μm.
[0027]
The solid catalyst component as described above is prepared by contacting a magnesium compound, a titanium halide compound and an electron donating compound. As the magnesium compound, magnesium halide such as magnesium dichloride or alkoxymagnesium is preferably used. Examples of dialkoxymagnesium include diethoxymagnesium, dipropoxymagnesium, dibutoxymagnesium, ethoxypropoxymagnesium, and butoxyethoxymagnesium. Of these, magnesium dichloride and diethoxymagnesium are preferred. Furthermore, in order to prepare the solid catalyst component having the above-mentioned particle characteristics, it is desirable that these magnesium compounds as the support also have particle characteristics substantially equivalent to the particle characteristics of the above-described solid catalyst component. Such a magnesium compound carrier is prepared by various methods. In the case of magnesium dichloride or diethoxymagnesium, it is first refined by mechanical pulverization or crushing such as a vibration mill or a homogenizer, and this is spray-dried or the like. Aggregation is performed by the method to form carrier particles.
[0028]
Of the above magnesium compounds, diethoxymagnesium is particularly preferred. The bulk specific gravity of diethoxymagnesium should be 0.20 to 0.40 g / ml, more preferably 0.23 to 0.37 g / ml, particularly preferably 0.25 to 0.35 g / ml. Is desirable. If the bulk specific gravity is less than 0.20 g / ml, it is impossible to obtain a high stereospecific polyolefin having a high bulk specific gravity in a high yield. On the other hand, if the bulk specific gravity exceeds 0.40 g / ml, it adversely affects the particle properties of the produced polyolefin. Here, the bulk specific gravity is measured according to JIS K6721 (1977).
[0029]
The pore volume of diethoxymagnesium is preferably 0.01 to 0.1 ml / g, more preferably 0.01 to 0.06 ml / g, still more preferably 0.015 to 0.05 ml / g. It is desirable to be in the range of. Thus, when a solid catalyst component prepared using porous diethoxymagnesium having a relatively small pore volume in a specific range is used for the polymerization of olefins, it has high stereoregularity and excellent particle properties. In addition, in block copolymerization, it is possible to obtain a copolymer with excellent particle properties in high yield even when the production rate of rubbery polymer is high. It becomes.
[0030]
Furthermore, the pore volume distribution of diethoxymagnesium is ln (R90 / R10) (where R90 is the pore radius at 90% of the cumulative pore volume, and R10 is the pore at 10% of the cumulative pore volume. The radius is 1.5 or more, preferably in the range of 1.5 to 3.5, and more preferably in the range of 2.0 to 3.0. Thus, what has a certain wide pore volume distribution is preferable. Here, the pore volume distribution is measured by a method using an adsorption isotherm of nitrogen gas.
[0031]
Furthermore, the nitrogen adsorption specific surface area (N₂ SA) is 5-50m²/ G, preferably 10 to 40 m²/ G, more preferably 15-30 m²/ G is desirable, and the shape is more preferably spherical or elliptical and has a narrower particle size distribution. Here, the spherical or elliptical sphere does not necessarily need to be a true sphere or elliptical sphere having a smooth surface by microscopic observation, and the ratio of the major axis diameter l to the minor axis diameter w (l / w) is the spherical coefficient of the particles. 3 or less, preferably 1 to 2, more preferably 1 to 1.5. Therefore, for example, a potato-like shape, that is, a particle shape having irregularities on the surface can be used. Thus, the solid catalyst component obtained using spherical or elliptical diethoxymagnesium is also spherical or elliptical, and the polyolefin produced using the solid catalyst component also has the same spherical or elliptical shape, As a result, a polymer having excellent fluidity is obtained, which is an advantage in the polyolefin production process.
[0032]
Furthermore, the average particle diameter of diethoxymagnesium is 1 to 100 μm, preferably 10 to 80 μm, more preferably 15 to 60 μm, and the particle size distribution is small in fine powder and coarse powder and has a narrow particle size distribution width. It is desirable. Specifically, particles of 5 μm or less are 20% by weight or less, preferably 15% by weight or less, more preferably 10% by weight or less, and particles of 100 μm or more are 10% by weight or less, preferably 5% by weight or less. Is. Further, the particle size distribution is (D90-D10) / D50 (where D90 is the particle size of 90% by weight of the integrated particle size, D10 is the particle size of 10% by weight of the integrated particle size, and D50 is 50% by weight of the integrated particle size. In this case, the particle size is 3 or less, preferably 2.5, and more preferably 2 or less. Thus, by using dialkoxymagnesium with a small amount of fine powder, it is possible to reduce the resulting fine powder of polyolefin.
[0033]
As described above, for example, the following method is preferably used for diethoxymagnesium having a high bulk specific gravity, a spherical or elliptical sphere having a specific pore volume, and a narrow particle size distribution with little fine and coarse powder. That is, magnesium metal and ethanol are directly reacted in the absence of a solvent or in the presence of a catalyst to produce diethoxymagnesium. In this method, the final addition ratio of metal magnesium and ethanol to the reaction system is metal magnesium / ethanol (weight ratio) = 1/9 to 15/1, and the metal magnesium and ethanol of the final addition ratio are added to the ethanol reaction system. Add continuously or intermittently, react for 5 to 80 minutes, and then hold for 1 to 30 hours under reflux of ethanol for aging reaction. The metal magnesium used in the above method is preferably, for example, several tens to several hundreds of mesh, more specifically about 100 mesh of powdery good reactivity.
[0034]
Examples of the catalyst include alkyl halides such as methyl bromide, methyl chloride, ethyl bromide and ethyl chloride, metal halides such as magnesium chloride and aluminum chloride, dialkoxymagnesium such as diethoxymagnesium, iodine and acetic acid. Esters are used, among which iodine is preferably used.
[0035]
Furthermore, in order to prepare the solid catalyst component having the average particle diameter, specific surface area, pore volume and pore distribution in the specific ranges described above, in addition to the above-mentioned characteristics of diethoxymagnesium, fine primary particles Is agglomerated with a certain degree of strength to form secondary particles. The primary particle size is 0.01 to 0.1 μm. Such diethoxymagnesium can be obtained by adjusting the preparation conditions, and primary particles become smaller by increasing the initial reaction rate. As a specific means, the amount of catalyst present during the reaction of metal magnesium and ethanol is increased. More specifically, the amount of catalyst such as iodine is 0.1 g or more, preferably 0.13 g or more per 1 g of metal magnesium used for the reaction. Particularly preferred is a method of adding 0.15 g or more, or a method of increasing the addition rate when metallic magnesium and ethanol are continuously or intermittently added to the ethanol reaction system.
[0036]
Specifically, as the titanium halide compound, TiCl_Four, Ti (OCH_Three) Cl_Three,
Ti (OC₂H_Five) Cl_Three, Ti (OC_ThreeH₇) Cl_Three, Ti (O-n-C_FourH₉) Cl_Three, Ti (OCH_Three)₂Cl₂, Ti (OC₂H_Five)₂Cl₂, Ti (OC_ThreeH₇)₂Cl₂, Ti (O-n-C_FourH₉)₂Cl₂ , Ti (OCH_Three)_ThreeCl, Ti (OC₂H_Five)_ThreeCl, Ti (OC_ThreeH₇)_ThreeCl, Ti (O-n-C_FourH₉)_ThreeCl etc. are exemplified, and among these, TiCl_FourIs preferably used. These tetravalent titanium halide compounds can be used alone or in combination of two or more.
[0037]
An electron-donating compound is an organic compound containing an oxygen atom or a nitrogen atom. For example, alcohols, phenols, ethers, esters, ketones, acid halides, aldehydes, amines, amides, nitriles , Isocyanates, organosilicon compounds containing Si—O—C bonds, and the like. Specifically, alcohols such as methanol, ethanol, n-propanol and 2-ethylhexanol, phenols such as phenol and cresol, methyl ether, ethyl ether, propyl ether, butyl ether, amyl ether, diphenyl ether, 9,9- Ethers such as bis (methoxymethyl) fluorene and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, methyl formate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate, ethyl butyrate , Methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, methyl p-toluate, ethyl p-toluate, methyl anisate, anisic acid Monocarboxylic esters such as chill, dicarboxylic esters such as diethyl maleate, dibutyl maleate, dimethyl adipate, diethyl adipate, dipropyl adipate, dibutyl adipate, diisodecyl adipate, dioctyl adipate, phthalate diester , Ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, acetophenone, benzophenone, acid halides such as phthalic acid dichloride, terephthalic acid dichloride, aldehydes such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, methylamine, ethylamine, triphenyl Amines such as butylamine, piperidine, aniline, pyridine, amides such as oleic acid amide, stearic acid amide, acetonitrile, benzoic acid Nitriles such as ril and tolunitrile, isocyanates such as methyl isocyanate and ethyl isocyanate, Si-O-C such as phenylalkoxysilane, alkylalkoxysilane, phenylalkylalkoxysilane, cycloalkylalkoxysilane, and cycloalkylalkylalkoxysilane Mention may be made of organosilicon compounds containing bonds.
[0038]
Of the electron donating compounds, esters, particularly aromatic dicarboxylic acid diesters are preferably used, and phthalic acid diesters are particularly preferable. Specific examples of these phthalic acid diesters include dimethyl phthalate, diethyl phthalate, di-n-propyl phthalate, di-iso-propyl phthalate, di-n-butyl phthalate, and di-iso-butyl phthalate. , Ethyl methyl phthalate, methyl phthalate (iso-propyl), ethyl phthalate (n-propyl), ethyl phthalate (n-butyl), ethyl phthalate (iso-butyl), di-n-pentyl phthalate, Di-iso-pentyl phthalate, di-neo-pentyl phthalate, dihexyl phthalate, di-n-heptyl phthalate, di-n-octyl phthalate, bis (2,2-dimethylhexyl) phthalate, phthalic acid Bis (2-ethylhexyl), di-n-nonyl phthalate, di-iso-decyl phthalate, bis (2,2-dimethylheptyl phthalate) ), N-butyl phthalate (iso-hexyl), n-butyl phthalate (2-ethylhexyl), n-pentylhexyl phthalate, n-pentyl phthalate (iso-hexyl), iso-pentyl phthalate (heptyl) N-pentyl (2-ethylhexyl) phthalate, n-pentyl phthalate (iso-nonyl), iso-pentyl phthalate (n-decyl), n-pentyl undecyl phthalate, iso-pentyl phthalate (iso- Hexyl), n-hexyl phthalate (2,2-dimethylhexyl), n-hexyl phthalate (2-ethylhexyl), n-hexyl phthalate (iso-nonyl), n-hexyl phthalate (n-decyl), N-heptyl phthalate (2-ethylhexyl), n-heptyl phthalate (iso-nonyl), n-phthalate Heptyl (neo-decyl) phthalate 2-ethylhexyl (an iso-nonyl) are exemplified. One or more of these are used. The above esters are preferably used in combination of two or more, and the esters are used so that the total carbon number of the alkyl group of the ester used is 4 or more compared to that of other esters. It is desirable to combine.
[0039]
Further, those having 1 or 2 alkyl groups having 1 to 5 carbon atoms or halogen atoms such as chlorine, bromine and fluorine substituted on the aromatic rings of these phthalic acid diesters are also preferably used. Specifically, dineopentyl 4-methylphthalate, dineopentyl 4-ethylphthalate, dineopentyl 4,5-dimethylphthalate, dineopentyl 4,5-diethylphthalate, diethyl 4-chlorophthalate, di-n-butyl 4-chlorophthalate Diisobutyl 4-chlorophthalate, diisohexyl 4-chlorophthalate, diisooctyl 4-chlorophthalate, diethyl 4-bromophthalate, di-n-butyl 4-bromophthalate, diisobutyl 4-bromophthalate, diisohexyl 4-bromophthalate, 4-bromophthalate Diisooctyl acid, diisoneopentyl 4-bromophthalate, diethyl 4,5-dichlorophthalate, di-n-butyl 4,5-dichlorophthalate, diisohexyl 4,5-dichlorophthalate, 4,5-dichlorophthalic acid Diiso Rot and the like.
[0040]
The solid catalyst component can be prepared by contacting the magnesium compound, the titanium halide compound and the electron donating compound, and this contact can be processed in the absence of an inert organic solvent. In consideration of ease of operation, it is preferable to perform the treatment in the presence of the solvent. Examples of the inert organic solvent used include saturated hydrocarbon compounds such as hexane, heptane, and cyclohexane, aromatic hydrocarbon compounds such as benzene, toluene, xylene, and ethylbenzene, orthodichlorobenzene, methylene chloride, carbon tetrachloride, dichloroethane, and the like. Among them, aromatic hydrocarbon compounds having a boiling point of about 90 to 150 ° C. and in a liquid state at room temperature, specifically, toluene, xylene and ethylbenzene are preferably used. The contact of each component is performed with stirring in a container equipped with a stirrer in an inert gas atmosphere and in a state where moisture and the like are removed. The contact temperature may be a relatively low temperature range around room temperature when the mixture is simply brought into contact with stirring and mixed, or dispersed or suspended for modification, but the product is allowed to react after contact. When obtaining, the temperature range of 40-130 degreeC is preferable. If the temperature during the reaction is less than 40 ° C., the reaction does not proceed sufficiently, resulting in insufficient performance of the prepared solid catalyst component, and if it exceeds 130 ° C., evaporation of the solvent used becomes remarkable. Therefore, it becomes difficult to control the reaction. The reaction time is 1 minute or longer, preferably 10 minutes or longer, more preferably 30 minutes or longer. When the above-mentioned specific magnesium compound is used as a carrier, it is necessary to prepare a solid catalyst component by contacting with a halogenated titanium compound and an electron donating compound while maintaining the particle characteristics as it is, and particularly diethoxymagnesium is used. In this case, since a rapid halogenation reaction proceeds by contact with the titanium halide compound and the particles may be destroyed, it is necessary to pay attention to the conditions of the contact reaction particularly in the initial stage.
[0041]
Preferred methods for preparing the solid catalyst component include the following methods. For example, a suspension is formed by suspending dialkoxymagnesium in a liquid aromatic hydrocarbon compound at room temperature such as toluene, and this suspension is then placed in titanium tetrachloride and the temperature of the reaction system is lowered. Add while maintaining. A preferable temperature range at this time is −15 to 5 ° C., more preferably −10 to 0 ° C. After completion of the addition, the reaction is kept at a lower temperature for aging reaction. The preferable temperature range at this time is also −15 to 5 ° C., more preferably −10 to 0 ° C. Thereafter, the temperature is raised and the reaction is carried out at 70 to 120 ° C. At this time, before or after contacting titanium tetrachloride with the above suspension, an electron donating compound such as phthalic acid diester is contacted at −20 to 130 ° C. to obtain a solid reaction product. After washing the solid reaction product with a liquid aromatic hydrocarbon compound at room temperature, titanium tetrachloride is added again in the presence of the aromatic hydrocarbon compound, and contact reaction is performed at 70 to 120 ° C., and further at room temperature. The solid catalyst component is obtained by washing with a liquid hydrocarbon compound. Furthermore, repeated contact with titanium tetrachloride is also a preferred embodiment for improving the activity of the catalyst.
[0042]
The amount ratio of each compound varies depending on the preparation method and cannot be defined unconditionally. For example, 0.5 to 100 mol, preferably 0.5 to 50 mol, of titanium halide compound per mol of magnesium compound Preferably it is 1-10 mol, and an electron-donating compound is 0.01-10 mol, Preferably it is 0.01-1 mol, More preferably, it is 0.02-0.6 mol.
[0043]
Examples of the organoaluminum compound used in forming the polymerization catalyst include triethylaluminum, diethylaluminum chloride, tri-iso-butylaluminum, diethylaluminum bromide, diethylaluminum hydride, and one or more can be used. . Triethylaluminum and tri-iso-butylaluminum are preferable.
[0044]
As the external electron donating compound used for forming the polymerization catalyst, the same electron donating compounds as those constituting the solid catalyst component described above are used, and among them, 9,9-bis (methoxymethyl) Preference is given to ethers such as fluorene and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, esters such as methyl benzoate and ethyl benzoate, and organosilicon compounds. As the organosilicon compound, the general formula R¹ _qSi (OR²)_4-q(Where R¹Represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, a phenyl group, a vinyl group, an allyl group, or an aralkyl group, which may be the same or different. R²Represents an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group, a phenyl group, a vinyl group, an allyl group, or an aralkyl group, which may be the same or different. q is an integer of 0 ≦ q ≦ 3. ) Is used. Examples of such an organosilicon compound include phenylalkoxysilane, alkylalkoxysilane, phenylalkylalkoxysilane, cycloalkylalkoxysilane, and cycloalkylalkylalkoxysilane.
[0045]
Specific examples of the organosilicon compound include trimethylmethoxysilane, trimethylethoxysilane, tri-n-propylmethoxysilane, tri-n-propylethoxysilane, tri-n-butylmethoxysilane, tri-iso-butylmethoxy. Silane, tri-t-butylmethoxysilane, tri-n-butylethoxysilane, tricyclohexylmethoxysilane, tricyclohexylethoxysilane, cyclohexyldimethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxy Silane, di-n-propyldimethoxysilane, di-iso-propyldimethoxysilane, di-n-propyldiethoxysilane, di-iso-propyldiethoxy Orchid, di-n-butyldimethoxysilane, di-iso-butyldimethoxysilane, di-t-butyldimethoxysilane, di-n-butyldiethoxysilane, n-butylmethyldimethoxysilane, bis (2-ethylhexyl) dimethoxysilane Bis (2-ethylhexyl) diethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, bis (3-methylcyclohexyl) dimethoxysilane, bis (4-methylcyclohexyl) dimethoxysilane Bis (3,5-dimethylcyclohexyl) dimethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, cyclohexylcyclo Nthyldipropoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, 3,5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, 3,5 -Dimethylcyclohexylcyclohexyldimethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane, cyclopentyl (iso-propyl) dimethoxysilane, cyclopentyl (iso-butyl) dimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldi Ethoxysilane, Cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclohexyl (n-propyl) dimethoxysilane, cyclohexyl (iso-propyl) dimethoxysilane, cyclohexyl (n-propyl) diethoxysilane, cyclohexyl (iso-butyl) dimethoxysilane, cyclohexyl ( n-butyl) diethoxysilane, cyclohexyl (n-pentyl) dimethoxysilane, cyclohexyl (n-pentyl) diethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenylethyldimethoxy Silane, phenylethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimeth Sisilane, ethyltriethoxysilane, n-propyltrimethoxysilane, iso-propyltrimethoxysilane, n-propyltriethoxysilane, iso-propyltriethoxysilane, n-butyltrimethoxysilane, iso-butyltrimethoxysilane, t -Butyltrimethoxysilane, n-butyltriethoxysilane, 2-ethylhexyltrimethoxysilane, 2-ethylhexyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, vinyltrimethoxy Silane, vinyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, tet Propoxysilane, mention may be made of tetrabutoxysilane and the like. Among the above, di-n-propyldimethoxysilane, di-iso-propyldimethoxysilane, di-n-butyldimethoxysilane, di-iso-butyldimethoxysilane, di-t-butyldimethoxysilane, di-n-butyldi Ethoxysilane, t-butyltrimethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxy Silane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane, cyclohexylsilane Lopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, and 3,5-dimethylcyclohexylcyclopentyldimethoxysilane are preferably used. Two or more types can be used in combination.
[0046]
The amount ratio of the solid catalyst component, the organoaluminum compound, and the external electron donating compound is arbitrary as long as it does not affect the effect of the present invention, and is not particularly limited. Is used in the range of 1 to 2000 mol, preferably 50 to 1000 mol, per mol of titanium atom in the solid catalyst component. The external electron donating compound is used in an amount of 0.002 to 10 mol, preferably 0.01 to 2 mol, particularly preferably 0.01 to 0.5 mol, per mol of the organoaluminum compound.
[0047]
The order of contacting the components is arbitrary, but it is desirable to first introduce the organoaluminum compound into the polymerization system, then contact the external electron donating compound, and then contact the solid catalyst component.
[0048]
Further, in producing the propylene block copolymer of the present invention using the above catalyst, prepolymerization is carried out prior to the main polymerization in order to further improve the catalytic activity, stereoregularity, particle properties of the resulting polymer, and the like. It is desirable. In the prepolymerization, the same olefins as in the main polymerization or monomers such as styrene can be used. In conducting the prepolymerization, the order of contacting each component and the monomer is arbitrary, but preferably, an organoaluminum compound is first charged into a prepolymerization system set to an inert gas atmosphere or a gas atmosphere for performing polymerization such as propylene. Then, after contacting the solid catalyst component, an olefin such as propylene and / or one or more other olefins are contacted. When prepolymerization is performed in combination with an external electron donating compound, an organoaluminum compound is first charged in a prepolymerization system set to an inert gas atmosphere or a gas atmosphere to carry out polymerization of propylene, etc. A method in which a compound is contacted and a solid catalyst component is further contacted, and then an olefin such as propylene and / or one or other two or more olefins is contacted is desirable.
[0049]
【Example】
Next, an example of the present invention will be specifically described in comparison with a comparative example. Each characteristic of the polymer was evaluated by the following method.
[0050]
(Melt index (melt flow rate) value (MFR))
It measured according to the method of ASTM D1238.
[0051]
(Flexural modulus)
After blending a heat-resistant stabilizer with the polymer, it was pelletized with an extruder, molded with an injection molding machine to prepare a measurement sample, and measured at 23 ° C. according to ASTM D790.
[0052]
(Izod impact strength)
After blending the polymer with a heat stabilizer, it was pelletized with an extruder, molded with an injection molding machine to prepare a measurement sample, and measured for an injection molded test piece with a notch at 23 ° C. according to ASTM D256.
[0053]
(Composition of propylene block copolymer)
Ratio of rubber part (block ratio), ratio of rubber part on the surface, average diameter of PP part section, average diameter of rubber part section, 90% cumulative distribution of rubber part diameter and Dpp / Dr were measured by transmission electron microscope (H- 7100FA type; manufactured by Hitachi, Ltd.) and an image processing apparatus (LUZEX F type; manufactured by Nireco) were used for analysis. Moreover, MFR was measured according to the method of ASTM D1238. Moreover, PP part xylene insoluble matter was calculated | required with the following method. 4.0 g of polymer was charged into 200 ml of paraxylene and dissolved at boiling point (138 ° C.) over 2 hours. Thereafter, the mixture was cooled to 23 ° C., and the dissolved component and the insoluble component were separated by filtration. The dissolved component was dried by heating, and the resulting polymer was used as a xylene-soluble component (XS) (% by weight).
[0054]
(Ethylene content, EPR content)
The ethylene content in the propylene block copolymer is¹³Quantified by C-NMR. Further, the content of ethylene propylene rubber component (EPR) in the propylene block copolymer was measured by the following method. To a 1-liter flask equipped with a stirrer and a condenser tube, about 2.5 g of the copolymer, 8 mg of 2,6-di-t-butyl-p-cresol, and 250 ml of p-xylene were added, Stir until the polymer is completely dissolved. Next, the flask was cooled to room temperature and left for 15 hours to precipitate a solid. This was separated into a solid and a liquid phase part by a centrifuge. Thereafter, the separated solid was taken in a beaker, 500 ml of acetone was poured in, stirred for 15 hours at room temperature, the solid was filtered and dried, and the weight was measured (this weight is designated as B). Further, the same operation was performed on the separated liquid phase portion, and a solid was precipitated, and the weight was measured (this weight is C 1). The content (% by weight) of the ethylene propylene rubber component (EPR) in the copolymer was calculated by the formula [C (g) / [B (g) + C (g)] × 100].
[0055]
(Fluidity of propylene block copolymer)
As shown in FIG. 3, set the funnel 1 (upper diameter: 91 mm, damper position diameter: 8 mm, inclination angle: 20 °, height to the damper position: 114 mm) with the damper 2 at the outlet position, Using a device in which a container-like receiver 3 (inner diameter: 40 mm, height: 81 mm) is installed at the bottom of the damper 2 with a spacing of 38 mm, first, 50 g of the polymer is put into the upper funnel 1 and then the damper is placed. 2 was opened, the polymer was dropped into the receiver 3, and the time for all the polymers to drop was measured. Propylene homopolymer obtained by polymerizing this operation using the same solid catalyst component as that used for propylene block copolymer and polymerization of this propylene block copolymer (in the production of the heavy propylene block copolymer of Example 1) Polymer obtained by carrying out only the polymerization reaction of propylene), the drop times were T1 and T2, respectively, and the value obtained by T1 / T2 was shown as fluidity.
[0056]
Example 1
(Preparation of diethoxymagnesium)
100 g of iodine was dissolved in 1000 ml of ethanol and heated to reflux. Into this, a slurry of metal magnesium and ethanol was continuously added over 2 hours, and a total of 500 g of metal magnesium was added and reacted under reflux. At this time, the amount of ethanol was 7.6 l. Thereafter, the mixture was aged for 3 hours, and the resulting solid was washed with ethanol and dried to obtain diethoxymagnesium powder. When this diethoxymagnesium was analyzed, the bulk specific gravity was 0.31 g / ml, the specific surface area (N₂SA) 19.8m²/ G, sphericity (l / w) 1.10, average particle size 25 μm, pore volume 0.02 ml / g, pore distribution [ln (R90 / R10)] 2.30, fine powder content 5 or less 5 μm %, Particle size distribution [(D90-D10) / D50] 1.05.
[0057]
(Preparation of solid catalyst component)
A 2000 ml round bottom flask equipped with a stirrer and sufficiently substituted with nitrogen gas was charged with 150 g of diethoxymagnesium, 750 ml of toluene, and 54 ml of di-n-butyl phthalate, and suspended. The suspension was then continuously added over a period of 1 hour in a solution of 450 ml toluene and 300 ml titanium tetrachloride pre-charged in a 3000 ml round bottom flask equipped with a stirrer and thoroughly substituted with nitrogen gas. Added to. At that time, the temperature of the reaction system was kept at -5 ° C. The mixed solution was stirred for 1 hour while being kept at −5 ° C., then heated to 100 ° C. over 4 hours, and reacted for 2 hours while stirring. Subsequently, after completion of the reaction, the product was contact-reacted for 2 hours while maintaining a temperature of 80 ° C. and stirring. Next, the product was washed 7 times with 40 ° C. heptane, filtered and dried to obtain a powdery solid catalyst component. The titanium content in the solid catalyst component was measured and found to be 3.15% by weight. The average particle diameter, specific surface area, pore volume and pore distribution of the solid catalyst component were measured. The results are shown in Table 3.
[0058]
(Production of propylene block copolymer)
Into an autoclave with a stirrer having an internal volume of 2.0 liters completely substituted with nitrogen gas, 0.0026 mmol of triethylaluminum (TEAL), cyclohexylmethyldimethoxysilane (CMDMS) and the solid catalyst component as titanium atoms was charged, A polymerization catalyst was formed. At this time, the molar ratio of Ti, TEAL and CMDMS (Ti / TEAL / CMDMS) in the solid catalyst component was 1/400/67. Thereafter, 2.0 liters of hydrogen gas and 1.2 liters of liquefied propylene were charged, and a propylene polymerization reaction was performed at 70 ° C. for 1 hour, so that a PP part ratio was about 70% by weight. Then, while supplying ethylene gas and propylene gas at an ethylene / propylene molar ratio of 0.7, polymerization is carried out in a gas phase at 70 ° C. for 2 hours at a pressure of 1.7 MPa so that the rubber part ratio is about 30% by weight. In addition, a propylene block copolymer was produced. A TEM (transmission electron microscope) photograph of the obtained propylene block copolymer is shown in FIG. 1, rubber part ratio (block ratio), rubber part ratio on the surface, ethylene content, EPR content, PP part MFR, PP Table 3 shows the xylene insoluble content, the average diameter of the PP section, the average diameter of the rubber section, 90% cumulative distribution of the diameter of the rubber section, Dpp / Dr, MI, flexural modulus, and Izod impact strength. The MFR in the PP part and the xylene-insoluble matter in the PP part are obtained by measuring the reaction product after the propylene polymerization reaction.
[0059]
Example 2
(Production of propylene block copolymer)
Except that propylene polymerization was carried out at 70 ° C. for 0.5 hours and ethylene propylene copolymerization was carried out at 70 ° C. for 2 hours to produce a propylene block copolymer in order to obtain a rubber part ratio of 63.5% by weight. Performed in the same manner as in Example 1. A TEM (transmission electron microscope) photograph of the obtained propylene block copolymer is shown in FIG. 2, and characteristic values similar to those of Example 1 are shown in Table 3, respectively.
[0060]
Example 3
(Preparation of diethoxymagnesium)
100 g of iodine was dissolved in 1000 ml of ethanol and heated to reflux. Into this, a slurry of metallic magnesium and ethanol was continuously added over 1 hour, and a total of 500 g of metallic magnesium was added and reacted under reflux. At this time, the amount of ethanol was 7.6 l. Thereafter, the mixture was aged for 3 hours, and the resulting solid was washed with ethanol and dried to obtain diethoxymagnesium powder. When this diethoxymagnesium was analyzed, the bulk specific gravity was 0.30 g / ml, the specific surface area (N₂SA) 20.5m²/ G, sphericity (l / w) 1.05, average particle size 24 μm, pore volume 0.018 ml / g, pore distribution [ln (R90 / R10)] 2.10, fine powder content 5 or less 5 μm %, Particle size distribution [(D90-D10) / D50] 1.05.
[0061]
(Preparation of solid catalyst component and production of propylene block copolymer)
A solid catalyst component was prepared and a propylene block copolymer was prepared in the same manner as in Example 1 except that the diethoxymagnesium obtained above was used. The obtained results are shown in Table 3.
[0062]
Example 4
(Preparation of solid catalyst component)
A 2000 ml round bottom flask equipped with a stirrer and thoroughly substituted with nitrogen gas was charged with 150 g of diethoxymagnesium prepared in Example 1, 750 ml of toluene and 54 ml of di-n-butyl phthalate and suspended. It was in a state. The suspension was then continuously added over a period of 1 hour in a solution of 450 ml toluene and 300 ml titanium tetrachloride pre-charged in a 3000 ml round bottom flask equipped with a stirrer and thoroughly substituted with nitrogen gas. Added to. At that time, the temperature of the reaction system was kept at -8 ° C. The mixed solution was stirred for 1 hour while being kept at -8 ° C, then heated to 100 ° C over 4 hours, and reacted for 2 hours with stirring. Subsequently, after completion of the reaction, the product was contact-reacted for 2 hours while maintaining a temperature of 80 ° C. and stirring. Next, the product was washed 7 times with 40 ° C. heptane, filtered and dried to obtain a powdery solid catalyst component. The titanium content in the solid catalyst component was measured and found to be 3.15% by weight. The average particle diameter, specific surface area, pore volume and pore distribution of the solid catalyst component were measured. The results are shown in Table 3.
[0063]
(Production of propylene block copolymer)
A propylene block copolymer was produced in the same manner as in Example 1 except that the solid catalyst component obtained above was used. The obtained results are shown in Table 3.
[0064]
Comparative Example 1
(Preparation of diethoxymagnesium)
A commercially available granular diethoxymagnesium (product name: magnesium ethylate, particle size: 500-1500 μm) manufactured by Huls was placed in a ball mill having an internal volume of about 10 liters substituted with nitrogen gas, and pulverized for 5 minutes. As a result of measuring the physical properties of the obtained diethoxymagnesium, the bulk specific gravity measured according to JIS K6721 was 0.41 g / ml, and the specific surface area (N₂SA) is 9.8m²/ G, sphericity (l / w) of 2.0, average particle size of 101.9 μm, pore volume of 0.010 ml / g, pore distribution [ln (D90 / D10)] of 2.63, 5 μm The following fine powder content rate was 4.1%, and particle size distribution [(D90-D10) / D50] was 2.44.
[0065]
(Preparation of solid catalyst component)
A 2000 ml round bottom flask equipped with a stirrer and sufficiently substituted with nitrogen gas was charged with 150 g of granular diethoxymagnesium, 750 ml of toluene and 54 ml of di-n-butyl phthalate, and suspended. did. The suspension was then continuously added over a period of 1 hour in a solution of 450 ml toluene and 300 ml titanium tetrachloride pre-charged in a 3000 ml round bottom flask equipped with a stirrer and thoroughly substituted with nitrogen gas. Added to. At that time, the temperature of the reaction system was maintained at 5 ° C. Then, it heated up to 100 degreeC over 4 hours, and was made to react for 2 hours, stirring. Subsequently, after completion of the reaction, the product was contact-reacted for 2 hours while maintaining a temperature of 80 ° C. and stirring. Next, the product was washed 7 times with 40 ° C. heptane, filtered and dried to obtain a powdery solid catalyst component. The titanium content in the solid catalyst component was measured and found to be 3.15% by weight. The average particle diameter, specific surface area, pore volume and pore distribution of the solid catalyst component were measured. The results are shown in Table 3.
[0066]
(Production of propylene block copolymer)
Experiments were conducted in the same manner as in Example 1 to obtain a propylene block copolymer. Table 3 shows the characteristic values of the resulting propylene block copolymer.
[0067]
Comparative Example 2
(Preparation of solid catalyst component)
Magnesium dichloride (95.2 g), decane (442 ml) and 2-ethylhexyl alcohol (390.6 g) were heated at 130 ° C. for 2 hours to form a homogeneous solution, and then phthalic anhydride (21.3 g) was added to the solution. Stir and mix at 1 ° C. for 1 hour to dissolve phthalic anhydride to obtain a uniform solution. After cooling to room temperature, 75 ml of this homogeneous solution is dropped into 200 ml of titanium tetrachloride, and then the temperature is raised to 110 ° C. When the temperature reaches 110 ° C., 5.22 g of diisobutyl phthalate is added and stirred for 2 hours. While reacting. After completion of the reaction, the product was resuspended in 275 ml of titanium tetrachloride and treated at 110 ° C. for 2 hours. Next, the product was washed 7 times with 40 ° C. heptane, filtered and dried to obtain a powdery solid catalyst component. The titanium content in the solid catalyst component was measured and found to be 2.80% by weight. The average particle diameter, specific surface area, pore volume and pore distribution of the solid catalyst component were measured. The results are shown in Table 3.
[0068]
(Production of propylene block copolymer)
Propylene polymerization was carried out at 70 ° C. for 1 hour and ethylene propylene copolymerization was carried out at 70 ° C. for 1 hour to produce a propylene block copolymer. It was. Table 3 shows the characteristic values of the resulting propylene block copolymer.
[0069]
Comparative Example 3
(Preparation of diethoxymagnesium)
In 1000 ml of ethanol, 10 g of iodine was dissolved and heated to boiling to reflux. Into this, a slurry of metal magnesium and ethanol was continuously added over 2 hours, and a total of 500 g of metal magnesium was added and reacted under reflux. At this time, the amount of ethanol was 7.6 l. Thereafter, the mixture was aged for 3 hours, and the resulting solid was washed with ethanol and dried to obtain diethoxymagnesium powder. When this diethoxymagnesium was analyzed, the bulk specific gravity was 0.26 g / ml, the specific surface area (N₂ SA) 19.8m²/ G, sphericity (l / w) 1.10, average particle size 31 μm, pore volume 0.03 ml / g, pore distribution [ln (R90 / R10)] 2.30, fine powder content 5 or less 5 μm %, Particle size distribution [(D90-D10) / D50] 1.05.
[0070]
(Preparation of solid catalyst component)
A 2000 ml round bottom flask equipped with a stirrer and sufficiently substituted with nitrogen gas was charged with 150 g of diethoxymagnesium, 750 ml of toluene, and 54 ml of di-n-butyl phthalate, and suspended. The suspension was then continuously added over a period of 1 hour in a solution of 450 ml toluene and 300 ml titanium tetrachloride pre-charged in a 3000 ml round bottom flask equipped with a stirrer and thoroughly substituted with nitrogen gas. Added to. At that time, the temperature of the reaction system was maintained at 10 ° C. The mixed solution was stirred for 1 hour while being kept at 10 ° C., then heated to 100 ° C. over 4 hours, and reacted for 2 hours with stirring. Subsequently, after completion of the reaction, the product was contact-reacted for 2 hours while maintaining a temperature of 80 ° C. and stirring. Next, the product was washed 7 times with 40 ° C. heptane, filtered and dried to obtain a powdery solid catalyst component. The titanium content in the solid catalyst component was measured and found to be 2.70% by weight. The average particle diameter, specific surface area, pore volume and pore distribution of the solid catalyst component were measured. The results are shown in Table 3.
[0071]
(Production of propylene block copolymer)
A copolymer was produced in the same manner as in Example 1 except that the solid catalyst component obtained as described above was used. The obtained results are shown in Table 3.
[0072]
[Table 3]

[0073]
【The invention's effect】
The propylene block copolymer of the present invention has a novel structure in which an ethylene-propylene copolymer, which is a rubber component, can be blended in a high ratio and a high dispersion in the propylene polymer. Further, since the rubber ratio on the particle surface is small and adhesion between polymer particles and adhesion to the inner wall of the apparatus does not occur, it is possible to produce a stable and high-quality block copolymer. In addition, since it has such a unique structure, it has a good balance in both performance of rigidity and impact resistance, and is particularly useful for applications such as automobile parts such as bumpers and household appliance parts.
[Brief description of the drawings]
1 is a TEM (transmission electron microscope) photograph of a cross section of a propylene block copolymer of Example 1. FIG.
2 is a TEM (transmission electron microscope) photograph of a cross section of the propylene block copolymer of Example 2. FIG.
FIG. 3 is a drawing of an apparatus for measuring the fluidity of a propylene block copolymer.

Claims (8)

A propylene block copolymer comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer, wherein the propylene polymer has an amorphous ethylene-propylene copolymer section. When the irregularly-shaped ethylene-propylene copolymer section is converted into a circle having the same area, the average diameter (Dr) of the ethylene-propylene copolymer section is the following formula (1):
Dr (μm) ≦ 0.005 × A (1)
(Wherein A represents the content (% by weight) of the ethylene-propylene copolymer in the propylene block polymer, and 20 ≦ A (% by weight) ≦ 80). Block copolymer. A propylene block copolymer comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer. The propylene polymer and the ethylene-propylene copolymer are complexed with each other. A propylene polymer section and an ethylene-propylene copolymer section, which are both mixed and have an indefinite shape, are formed, and when the ethylene-propylene copolymer section is converted into a circle of the same area, the ethylene-propylene copolymer section The average diameter of the polymer section (Dr) is the following formula (1):
Dr (μm) ≦ 0.005 × A (1)
(Wherein A represents the content (% by weight) of the ethylene-propylene copolymer in the propylene block polymer, and 20 ≦ A (% by weight) ≦ 80). Block copolymer. When the propylene polymer section is converted into a circle of the same area, the average diameter (Dpp) (μm) is the following formula (2):
5.0 ≧ Dpp (μm) ≧ e ^-0.02 × ^A (2)
The propylene block copolymer according to claim 2, wherein (wherein A is as defined above) is satisfied. The propylene block copolymer according to claim 1 or 2, wherein the propylene polymer is 30 to 70% by weight and the ethylene-propylene copolymer is 30 to 70% by weight. The particle diameter (Dr90) in the cumulative particle size distribution 90% of the diameter of the ethylene-propylene copolymer section is represented by the following formula (3):
Dr90 (μm) ≦ 0.01 × A (3)
The propylene block copolymer according to claim 1 or 2, wherein (wherein A is as defined above) is satisfied. A propylene block copolymer having a mean particle size of 100 to 5000 μm, comprising 20 to 80% by weight of a propylene polymer and 20 to 80% by weight of an ethylene-propylene copolymer, comprising ethylene on the particle surface A propylene block copolymer, wherein the proportion of the propylene copolymer is 0.3% by volume or less of the total ethylene-propylene block copolymer. The propylene block copolymer according to claim 1, which is obtained by polymerizing propylene and then copolymerizing ethylene and propylene. It contains magnesium, titanium and halogen atoms, has an average particle diameter of 1 to 100 μm, a specific surface area of 100 to 500 m ² / g, a pore volume of less than 0.2 ml / g, and a pore diameter of 100 mm or less. It is obtained by polymerizing propylene with a polymerization catalyst containing a solid catalyst component having a pore distribution with a cumulative pore volume of 50% or more, and then copolymerizing ethylene and propylene. 6. The propylene block copolymer according to 6.

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