JP4174352B2 - Propylene-based resin composition for sheet molding and transparent sheet using the same - Google Patents

Description

（ここで、Ｒ^１は炭素数１〜１０の２価炭化水素基であり、Ｒ^２およびＲ^３は水素又は炭素数１〜１０の炭化水素基であって、Ｒ^２とＲ^３は同じであっても異なっていてもよく、Ｍは１〜３価の金属原子であり、ｎは１〜３の整数である。）
【００４２】
【化２】

（ここで、Ｒ^１は炭素数１〜１０の２価炭化水素基であり、Ｒ^２およびＲ^３は水素又は炭素数１〜１０の炭化水素基であって、Ｒ^２とＲ^３は同じであっても異なっていてもよく、ｍは１又は２である。）
【００４３】
一般式（１）で表される化合物の具体例としては、ナトリウム−２，２’−メチレン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、リチウム−２，２’−メチレン−ビス−（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、リチウム−２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−エチリデン−ビス（４−ｉ−プロピル−６−ｔ−ブチルフェニル）フォスフェート、リチウム−２，２’−メチレン−ビス（４−メチル−６−ｔ−ブチルフェニル）フォスフェート、リチウム−２，２’−メチレン−ビス（４−エチル−６−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−ブチリデン−ビス（４，６−ジ−メチルフェニル）フォスフェート、ナトリウム−２，２’−ブチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−ｔ−オクチルメチレン−ビス（４，６−ジ−メチルフェニル）フォスフェート、ナトリウム−２，２’−ｔ−オクチルメチレン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、カルシウム−ビス−（２，２’−メチレン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート）、マグネシウム−ビス［２，２’−メチレン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート］、バリウム−ビス［２，２’−メチレン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート］、ナトリウム−２，２’−メチレン−ビス（４−メチル−６−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−メチレン−ビス（４−エチル−６−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−エチリデン−ビス（４−ｍ−ブチル−６−ｔ−ブチルフェニル）フォスフェート、ナトリウム−２，２’−メチレン−ビス（４，６−ジ−メチルフェニル）フォスフェート、ナトリウム−２，２’−メチレン−ビス（４，６−ジ−エチルフェニル）フォスフェート、カリウム−２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート、カルシウム−ビス［２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フオスフェート］、マグネシウム−ビス［２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート］、バリウム−ビス［２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート］、アルミニウム−トリス［２，２’−メチレン−ビス（４，６−ジ−ｔ−ブチルフェル）フォスフェート］およびアルミニウム−トリス［２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェート］、が挙げられ、これらの中ではナトリウム−２，２’−エチリデン−ビス（４，６−ジ−ｔ−ブチルフェニル）フォスフェートが好ましい。
【００４４】
一般式（２）で表される化合物は、Ｒ^２とＲ^３が共にｔ−ブチル基であるものが好ましく、その具体例としては、ビス（２，４，８，１０−テトラ−ｔ−ブチル−６−オキソ−１２Ｈ−ジベンゾ［ｄ，ｇ］［１，３，２］ジオキサホスホシン−６−オキシド）水酸化アルミニウム塩が挙げられる。
【００４５】
有機リン酸エステル系結晶化核剤の配合量は、プロピレン系重合体１００重量部に対して、０．０１〜２．０重量部、好ましくは０．０５〜１．０重量部、特に好ましくは０．１〜０．３重量部である。配合量がこの範囲未満であると目的とする透明性の改良効果がなく、逆にこの範囲を超えると配合量に応じた透明改良効果が飽和して経済的でない。
【００４６】
３．帯電防止剤
本発明のプロピレン系重合体組成物で用いられる帯電防止剤としては、非イオン系帯電防止剤、カチオン系帯電防止剤、両性イオン系帯電防止剤、アニオン系帯電防止剤等が挙げられる。
【００４７】
非イオン系帯電防止剤としては、グリセリン脂肪酸エステル、ソルビタン脂肪酸エステル、ポリオキシエチレンアルキルアミン、ポリオキシエチレンアルキルアミド、脂肪酸ジエタノールアミド、ポリオキシアルキレンアルキルエーテル、ポリオキシアルキレンアルキルフェニルエーテル、ポリオキシエチレン−ポリオキシプロピレンアルキルエーテル、脂肪酸のエチレンオキサイド付加体等が挙げられる。
【００４８】
グリセリン脂肪酸エステルとしては、グリセリンモノカプリル酸エステル、グリセリンモノラウリン酸エステル、グリセリンモノミリスチン酸エステル、グリセリンモノパルミチン酸エステル、グリセリンモノステアリン酸エステル、グリセリンモノオレイン酸エステル、グリセリンモノベヘニン酸エステル、グリセリンモノエルカ酸エステル等のモノグリセリン脂肪酸エステル類、ジグリセリンモノベヘニン酸エステル、ジグリセリンモノステアリン酸エステル、ジグリセリンモノオレイン酸エステル、ジグリセリンモノパルミチン酸エステル、ジグリセリンモノミリスチン酸エステル、ジグリセリンモノラウリン酸エステル等のジグリセリン脂肪酸エステル類が挙げられる。
【００４９】
ソルビタン脂肪酸エステルは、脂肪酸と多価アルコ−ルの一種であるソルビタンとのモノエステル乃至はトリエステル体である。
ポリオキシエチレンアルキルアミンは、ラウリルアミン等の高級アルキルアミンの２個の活性水素に酸化エチレンを反応させて窒素に結合した水素の１つまたは２つに酸化エチレンが付加重合して得られる。
ポリオキシエチレンアルキルアミドは、高級脂肪酸アミドに酸化エチレンの付加重合または高級脂肪酸アミドとポリエチレングリコ−ルの脱水縮合によって得られる。
脂肪酸ジエタノールアミドは、ラウリン酸ジエタノールアミド、パルチミン酸ジエタノールアミド、ステアリン酸ジエタノールアミド等が挙げられる。
ポリオキシアルキレンアルキルエーテルは、具体的には、ポリオキシエチレンアルキルエーテル等が挙げられ、ラウリル、セチル、オレイルアルコ−ル等のＣ１２〜Ｃ２２の高級脂肪族アルコ−ルに酸化エチレンを付加重合して得られる。
ポリオキシアルキレンアルキルフェニルエーテルは、具体的にはポリオキシエチレンアルキルフェニルエーテルが挙げられ、アルキルフェノ−ルまたはアルキルナフト−ルに酸化エチレンを付加重合して得られる。
【００５０】
非イオン系帯電防止剤のなかでは、グセリン脂肪酸エステルが好ましく、特にモノエステル含量が５０重量％以上のグリセリン脂肪酸エステルが好ましい。最も好ましくは有効成分がグリセリンモノパルミチン酸エステル、グリセリンモノステアリン酸エステル、グリセリンモノオレイン酸エステル、グリセリンモノエルカ酸エステルのものである。
【００５１】
さらに、両性イオン系帯電防止剤としてば、アルキルベタイン型等が例示され、カチオン系帯電防止剤としては、第４級アンモニウムクロライド等が例示され、アニオン系帯電防止剤としては、アルキルスルフォネート等のが挙げられるが、帯電防止性能、ロール汚れ性、印刷適性からより好ましい帯電防止剤は、非イオン系帯電防止剤である。
【００５２】
帯電防止剤の配合量は、プロピレン系重合体１００重量部に対して、０．０１〜２．０重量部、好ましくは０．０２〜０．５重量部、特に好ましくは０．０３〜０．３重量部である。配合量がこの範囲未満であると目的とする帯電防止性能や表面滑性効果が持続性をもって得られず、逆にこの範囲を超えると表面にブリードし外観不良等の問題を起こし易くなり好ましくない。
【００５３】
４．その他の成分
本発明のプロピレン系樹脂組成物には、本発明の目的を損ねない範囲で必要に応じて、上記以外の添加剤を処方することが可能であり、例えば、フェノール系酸化防止剤および／または、リン系酸化防止剤、中和剤、耐候剤、紫外線吸収剤、光安定剤、滑剤、分子量調整剤（過酸化物）、着色剤、各種フィラー等の各種助剤、プロピレン単独あるいは他のα−オレフィンとの共重合体、低密度ポリエチレン、高密度ポリエチレン等の他の熱可塑性樹脂、各種熱可塑性エラストマー、無機または有機充填剤等から少なくとも１種類以上添加剤を配合してシート成形用プロピレン系樹脂組成物とすることができる。
【００５４】
［ＩＩ］プロピレン系樹脂組成物の製造
本発明のプロピレン系樹脂組成物は、上記のプロピレン系共重合体に有機リン酸エステル系結晶化核剤と帯電防止剤、必要に応じて、その他の成分の所定量を混合して得られる。これらの混合には、例えば、ヘンシェルミキサーやスーパーミキサー等の高速撹拌機付混合機、リボンブレンダー、タンブラーなどの通常の混合装置が使用でき、混合後に押出機やニーダー等でペレット化することにより、プロピレン系樹脂組成物とすることができる。
【００５５】
［ＩＩＩ］シート
本発明のシートは、前述のプロピレン系樹脂組成物を用いて、公知の成形方法、例えば、押出成形法、カレンダー成形法、圧縮成形法、注型成形法等により製造することができる。好ましくは押出成形法であり、押出成形法としては、例えばＴダイ法、インフレーション法が挙げられる。押出されたシートは、ポリッシングロール法、エアーナイフ法、金属鏡面ベルト法、等の公知の方法で冷却固化される。層構成は単層でも、本発明の組成物層を少なくとも１層を含む多層であってもよい。
押出温度は、シートの透明性、成形性の点で１８０〜２６０℃が好ましく、１８０〜２４０℃がより好ましい。押出温度が１８０℃以上であれば、十分に溶融され、また２６０℃を超えると熱劣化が起き易くなり好ましくない。
【００５６】
本発明のシートは、透明性に優れ、ヘイズが好ましくは１５％以下であり、より好ましくは１〜１０％である。また、保存後のシートにおける透明性の低下も少ない。
本発明の透明シートの厚みは、特に制限されないが、通常０．１０〜３．０ｍｍ、特に文具用途では０．１５〜２．０ｍｍが好ましい。
また、本発明の透明シートは、本発明の目的を損ねない範囲で必要に応じて通常工業的に採用されているコロナ放電処理、火炎処理、プラズマ処理、オゾン処理などの表面処理を施すことも可能である。また、本発明の透明シートは表面に改質剤を塗布したり、貼り付けたりすることもできる。
【００５７】
本発明のシートは、透明性、剛性、低温での耐衝撃性、折曲げ時の耐白化性に優れ、かつ、帯電防止性や最近のオフセット印刷方法も含めた印刷性に優れ、さらにその効果の持続性に優れるので、文具向けシート、磁気記録媒体用包装ケースなどに好適に用いることができる。文具としては、ファイルケースやバインダー等が例示され、磁気記録媒体用包装ケースとしては、ビデオカセットやＤＶＤ等の包装ケース等が例示される。
【００５８】
【実施例】
以下、実施例によって具体的に説明するが、本発明の範囲は実施例のみに限定されるものではない。なお、発明の詳細な説明および実施例中の各項目の測定は下記の方法で実施した。
（１）ＭＦＲ（メルトフローレイト）：プロピレン系共重合体とプロピレン系樹脂組成物のＭＦＲは、ＪＩＳ−Ｋ７２１０（１９９９）「ポリプロピレン試験方法」のメルトフローレイト（温度２３０℃、荷重２１．１８Ｎ）に従って測定した。
なお、成分ＢのＭＦＲ_Ｂは、先の式に示したように、前段重合工程にて得られた成分ＡのＭＦＲ_Ａと、後段重合工程終了後に測定したＭＦＲ_Ｔおよび成分Ａの製造割合；Ｗ_Ａ重量％、成分Ｂの製造割合；Ｗ_Ｂ重量％から、次式により成分ＢのＭＦＲ_Ｂを決定した。
ｌｏｇ（ＭＦＲ_Ａ）×Ｗ_Ａ／１００＋ｌｏｇ（ＭＦＲ_Ｂ）×Ｗ_Ｂ／１００＝ｌｏｇ（ＭＦＲ_Ｔ）
（２）エチレン含有量：成分Ｂのエチレン含有量は、前段重合工程の成分Ａの重合終了後に測定したエチレン含有量；Ｅ_Ａと、後段重合工程の重合終了後に測定したエチレン含有量；Ｅ_{ＴＯＴＡＬ}および成分Ａの製造割合；Ｗ_Ａ重量％、成分Ｂの製造割合；Ｗ_Ｂ重量％から、次式により成分Ｂのエチレン含有量；Ｅ_Ｂを決定した。なお、エチレン含有量は、^１３Ｃ−ＮＭＲにて求めた。
Ｅ_Ａ×Ｗ_Ａ／１００＋Ｅ_Ｂ×Ｗ_Ｂ／１００＝Ｅ_{ＴＯＴＡＬ}
（３）金属ロール汚れ：押出シート成形時に冷却金属ロールの汚れ度合いを目視にて観察し、以下の基準で判定した。
○：汚れ無し。
△：僅かに汚れが発生。
×：著しく汚れが発生。
（４）透明性：ＪＩＳ−Ｋ７１３６−２０００に従ってＨＡＺＥを評価した。
シート成形１日後にＨＡＺＥを測定してこれをＨＡＺＥ１とし、さらにこのシートについて温度４０℃で１４日間保存した後にＨＡＺＥを測定した。このＨＡＺＥ値をＨＡＺＥ２とした。ＨＡＺＥ変化（ＨＡＺＥ２−ＨＡＺＥ１）の値が大きいほど表面外観が悪化した目安とした。
（５）引張弾性率：押出しシートの引張弾性率は、ＪＩＳ−Ｋ７１２７−１９９９に従って評価した。
（６）デュポン衝撃強度：押出シートのデュポン衝撃強度は、ＡＳＴＭ−Ｄ２７９４に準拠し、（株）東洋精機製作所製のデュポン衝撃強度測定機にて評価した。
（７）耐折曲げ白化性：押出シートを１８０度に折り曲げ、曲げた部分の白化性を目視にて観察し、以下の基準で判定した。
○：白化せず。
△：僅かに白化。
×：著しく白化。
（８）帯電防止性（帯電圧減衰半減期）：押出シート成形１日後にスタチックオネストメーター（宍戸静電気株式会社製）にかけて１０ｋｖ、２分間荷電し、荷電を停止した後の半減期を測定した。この値（秒）が小さいほど帯電防止性が優れている。
（９）印刷性：押出シートについてＲＩテスターを使用して印刷（印刷インクは東洋インキ社製のフラッシュドライＦＤＯ−Ｇ黒を使用した。）し、８０Ｗ／ｃｍ高圧水銀灯の下１０ｃｍを２４ｃｍ／分の速度で１０回通過させて紫外線硬化を行った。この印刷されたシートについて着色の濃さを目視にて観察し、着色性の判定とした。
○：鮮やかに着色した。
△：着色がやや薄い。
×：著しく着色が薄い。
【００５９】
実施例１
（１）プロピレン系共重合体の製造
（ｉ）固体触媒の製造
攪拌翼、温度計、ジャケット、冷却コイルを備えた１００リッターの反応器に、ジエトキシマグネシウム（以下、Ｍｇ（ＯＥｔ）_２と記す。）：３０ｍｏｌを仕込み、次いで、テトラブトキシチタン（以下、Ｔｉ（ＯＢｕ）_４と記す。）を、仕込んだＭｇ（ＯＥｔ）_２中のＭｇに対して、Ｔｉ（ＯＢｕ）_４／Ｍｇ＝０．６０（モル比）となるように仕込んだ。さらに、トルエンを１９．２ｋｇ仕込み、攪拌しながら昇温した。１３９℃で３時間反応させた後、１３０℃に降温して、メチルトリフェノキシシラン（以下、ＭｅＳｉ（ＯＰｈ）_３と記す。）のトルエン溶液を、先に仕込んだＭｇ（ＯＥｔ）_２中のマグネシウムに対して、ＭｅＳｉ（ＯＰｈ）_３／Ｍｇ＝０．６７（モル比）になるように添加した。なお、ここで用いたトルエン量は、７．８ｋｇであった。添加終了後、１３０Ｃで２時間反応させ、その後、室温に降温し、テトラエトキシシラン（以下、Ｓｉ（ＯＥｔ）_４と記す。）を添加した。Ｓｉ（ＯＥｔ）_４の添加量は、先に仕込んだＭｇ（ＯＥｔ）_２中のマグネシウムに対して、Ｓｉ（ＯＥｔ）_４／Ｍｇ＝０．０５６（モル比）となるようにした。
次に、得られた反応混合物に対して、マグネシウム濃度が、０．５８ｍｏｌ／Ｌ−トルエンになるように、トルエンを添加した。さらに、フタル酸ジエチル（以下、ＤＥＰと記す。）を、先に仕込んだＭｇ（ＯＥｔ）_２中のマグネシウムに対して、ＤＥＰ／Ｍｇ＝０．１０（モル比）になるように添加した。得られた混合物を、引き続き攪拌しながら１０℃に冷却し、四塩化チタン（以下、ＴｉＣｌ_４と記す。）を２時間かけて滴下して均一溶液を得た。なお、ＴｉＣｌ_４は、先に仕込んだＭｇ（ＯＥｔ）_２中のマグネシウムに対して、ＴｉＣｌ_４／Ｍｇ＝４．０（モル比）になるようにした。ＴｉＣｌ_４添加終了後、攪拌しながら０．５℃／ｍｉｎで１５℃まで昇温し、同温度で１時間保持した。次いで、再び０．５℃／ｍｉｎで５０℃まで昇温し、同温度で１時間保持した。さらに、１℃／ｍｉｎで１１８℃まで昇温し、同温度で１時間処理を行った。処理終了後、攪拌を停止し、上澄み液を除去した後、トルエンで、残液率＝１／７３（重量比）になるように洗浄し、スラリーを得た。
次に、ここで得られたスラリーに、室温で、トルエンとＴｉＣｌ_４を添加した。なお、ＴｉＣｌ_４は、先に仕込んだＭｇ（ＯＥｔ）_２中のマグネシウムに対して、ＴｉＣｌ_４／Ｍｇ（ＯＥｔ）_２＝５．０（モル比）となるようにした。また、トルエンは、ＴｉＣｌ_４濃度が、２．０ｍｏｌ／Ｌ−トルエンになるように調製した。このスラリーを攪拌しながら昇温し、１１８℃で１時間反応を行った。反応終了後、攪拌を停止し、上澄み液を除去した後、トルエンで、残液率＝１／１５０（重量比）となるように洗浄し、固体成分のスラリーを得た。
【００６０】
（ｉｉ）固体触媒成分（Ａ）の製造
得られた固体成分のうち、４００ｇを、攪拌翼、温度計、冷却ジャケットを有する別の反応器に移送し、ノルマルヘキサンを加えて、固体成分の濃度として５．０ｇ／ｌになるように希釈した。得られたスラリーを攪拌しながら、１５Ｃで、トリメチルビニルシラン、トリエチルアルミニウム（以下、ＴＥＡと記す。）およびターシャリーブチルメチルジエトキシシラン（以下、ＴＢＭＤＥＳと記す。）を添加した。なお、ＴＥＡ、トリメチルビニルシラン、ＴＢＭＤＥＳの添加量は、それぞれ、固体触媒成分（Ａ）中の固体成分１ｇに対して、３．１ｍｍｏｌ、０．２ｍｌ、０．２ｍｌとなるようにした。添加終了後、引き続き攪拌しながら、１５℃で１時間保持し、さらに、３０℃に昇温して、同温度で２時間攪拌した。次に、再び１５℃に降温し、同温度を保持しながら、反応器の気相部に、４．８ｋｇのプロピレンガスを８時間かけて定速でフィードして予備重合を行った。フィード終了後、攪拌を停止して上澄み液を除去した後、ノルマルヘキサンで洗浄を行い、固体触媒成分（Ａ）のスラリーを得た。なお、残液率は、１／１２（重量比）とした。得られた固体触媒成分（Ａ）は、固体触媒成分（Ａ）：１ｇあたり、１１．５ｇのプロピレン重合体を有していた。
【００６１】
（ｉｉｉ）プロピレン−エチレン共重合体の製造
内容積０．４ｍ^３の攪拌装置付き液相重合槽１、０．５ｍ^３の攪拌式気相重合槽２の間に、二重管式熱交換器と流動フラッシュ槽からなる脱ガスシステムを組み込んだプロセスにより、プロピレン−エチレン共重合体の連続製造を実施した。
液相重合槽１には、液化プロピレン、エチレン、水素、ＴＥＡ、ＴＢＥＤＭＳを連続的にフィードした。なお、液化プロピレン、ＴＥＡ、ＴＢＥＤＭＳのフィード量は、それぞれ、１６３ｋｇ／ｈｒ、２２．１ｇ／ｈｒ、１．９１ｇ／ｈｒであり、水素は気相の濃度が２．３８ｍｏｌ％に、エチレンは気相の濃度が１．５５ｍｏｌ％にそれぞれなるようにフィードした。さらに、上記（ｉｉ）で得られた固体触媒成分（Ａ）を、（Ａ）中に含まれる固体成分として、０．１３ｇ／ｈｒとなるようにフィードした。また、重合温度が７０℃となるように、重合槽を冷却した。
この重合槽１で重合したスラリーは、２重管式熱交換器により加熱され、流動フラッシュ槽に抜き出した。スラリーの抜き出しレートは、該スラリーに含まれるポリプロピレン粒子として、約２４ｋｇ／ｈｒになるように調節した。該ポリプロピレン粒子の液相重合槽１における平均滞留時間は１．４時間であった。流動フラッシュ槽においては、下部より加熱したプロピレンガスをフィードしながら、槽内温度を７０℃に維持した。この流動フラッシュ槽から、少量のサンプルとして抜き出したポリプロピレンを分析したところ、ＭＦＲは３．５ｇ／１０分、エチレンの含有量は３．０重量％であった。ここで得られた固体状ポリプロピレン粒子は、気相重合槽２に送り、さらにエチレンとプロピレンの共重合を行った。
エチレンとプロピレンは、エチレンとプロピレンの分圧の和が１７．０ｋｇｆ／ｃｍ^２Ｇ、かつ、エチレンのモル分率が４．１ｍｏｌ％で一定になるようにフィードした。また、水素は、水素濃度が０．７５ｍｏｌ％となるようにフィードした。重合温度は７５℃で、気相重合槽２から抜き出したプロピレン・エチレンブロック共重合体の抜き出しレートが、約３３ｋｇ／ｈｒになるように調節した。気相重合槽２における平均滞留時間は、１．７ｈｒであった。気相重合槽２から抜き出された重合体粒子を分析したところ、ＭＦＲは２．７ｇ／１０分、エチレンの含有量は４．０重量％であった。こららの結果より、１段目と２段目の重合量比は、それぞれ７５重量％、２５重量％、２段目の重合によって生成したエチレン−プロピレン共重合体のＭＦＲおよびエチレン含有量は、それぞれ１．２ｇ／１０分、７重量％であることがわかった。以上の重合条件、重合結果を表１に示した。
【００６２】
（２）プロピレン系樹脂組成物の製造
上記で得られたプロピレン系共重合体粉末１００重量部に、有機リン酸エステル系結晶化核剤として、ビス（２，４，８，１０−テトラ−ｔ−ブチルー６−オキソ−１２Ｈ−ジベンゾ［ｄ，ｇ］［１，３，２］ジオキサホスホシン−６−オキシド）水酸化アルミニウム塩（商品名：アデカ（株）製マークＮＡ２１、表中に「ＮＡ２１」と記載）０．２重量部、帯電防止剤として、グリセリンモノステアレート（商品名：（株）花王製エレクトロストリッパーＴＳ５、表中に「ＴＳ５」と記載）０．０７重量部、さらに、ステアリン酸カルシウム０．０３重量部、商品名イルガノックス１０１０（チバガイギー社製）０．２重量部を加えてヘンシェルミキサーで混合後、２５０℃で溶融混練し、ＭＦＲが２．６ｇ／１０分になるように調整しプロピレン系樹脂組成物を得た。得られた組成物の内容を表２に示す。
【００６３】
（３）シートの製造
このプロピレン系樹脂組成物を２３０℃に加熱されたスクリュー径５０ｍｍの押出シート成形機にてダイ幅５００ｍｍのコートハンガーダイから押出し、４０℃の水が内部で循環した硬質クロムメッキ加工の金属ロールで挟み冷却固化した後、コロナ放電処理機にて表面処理をかけながら表面張力４５ダインで厚み０．６ｍｍの押出シートを製造した。得られたシートの評価を行った。その結果を表２に示す。
【００６４】
実施例２〜４
実施例１の（ｉｉｉ）における１段目、２段目の重合条件を表１に示すとおりに調整し、表１に示すプロピレン系共重合体を得た。これらのプロピレン系共重合体を用い、実施例１と同様にして、プロピレン系樹脂組成物の製造、シート成形を行い評価した。得られた結果を表２に示す。
【００６５】
比較例１〜５
実施例１の（ｉｉｉ）における１段目、２段目の重合条件を表１に示すとおりに調整し、表１に示すプロピレン系ブロック共重合体を得た。これらのプロピレン系ブロック共重合体を用い、実施例１と同様にして、プロピレン系樹脂組成物の製造、シート成形を行い評価した。得られた結果を表２に示す。
【００６６】
【表１】

【００６７】
【表２】

【００６８】
なお、表２中のＮＡ２１、ＴＳ５以外の配合物は以下の通りである。
ゲルオールＭＤ（商品名）：新日本理化（株）製１，３，２，４−ジ（パラメチルベンジリデン）−ソルビトール
Ａ４０８５（商品名）：三井化学（株）製エチレン−ブテン−ランダム共重合エラストマー
【００６９】
表２より明らかなように、本発明のプロピレン系樹脂組成物からのシートは、弾性率、透明性、低温での耐衝撃性、折曲げ時の耐白化性に優れ、かつ帯電防止性や印刷性に優れたものであった（実施例１〜４）。一方、１段の重合工程のみによる共重合体の組成物では帯電防止性に劣り（比較例１）、１段の重合工程による共重合体にエチレン−ブテン共重合体エラストマーを配合した組成物では折り曲げ白化性及び帯電防止性に劣り（比較例２）、エチレン含有量の高い１段の重合工程のみによる共重合体の組成物では透明性に劣り（比較例３）、有機リン酸エステル系結晶化核剤以外の核剤を用いると金属ロール汚れがあり（比較例４）、前段の反応器におけるプロピレン・エチレン共重合体の生成量が多すぎる共重合体の組成物では衝撃強度に劣った（比較例５）。
【００７０】
【発明の効果】
本発明のシート成形用ポリプロピレン系樹脂組成物は、透明性、剛性、低温での耐衝撃性、折曲げ時の耐白化性に優れ、かつ帯電防止性や印刷性にも優れており、文具向けシート等の透明シート用途に好適なものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a propylene-based resin composition for forming a sheet and a transparent sheet using the same, and more specifically, it is excellent in transparency, rigidity, impact resistance at low temperature, and whitening resistance during bending, and antistatic. The present invention relates to a propylene-based resin composition for sheet molding having excellent properties and printability and a transparent sheet using the same.
[0002]
[Prior art]
Polypropylene polymer is a resin having excellent moldability, mechanical strength, heat resistance, and chemical stability, and is used in various applications including sheet or film applications. Among sheet applications, transparency is particularly demanded in recent years for sheets for stationery such as file cases and binders, and sheets for packaging cases such as video cassettes or DVDs that emphasize appearance.
Examples of techniques for imparting transparency to polypropylene polymer sheets include, for example, a method for improving transparency by copolymerizing propylene and an α-olefin such as ethylene to reduce crystallinity, and organic carboxylic acid. In addition, a method of adding and blending a metal salt of an organic carboxylic acid or a crystallization nucleating agent such as dibenzylidene sorbitol is widely used (see, for example, Patent Documents 1 and 2). However, these methods often result in insufficient polypropylene rigidity, low temperature impact resistance, and whitening resistance during bending.
In addition, the conventionally proposed improved method of blending polyethylene or olefinic rubber with polypropylene (see, for example, Patent Document 3) has a problem of greatly impairing transparency, and further includes a specific nucleating agent and polyethylene or olefin. Even when the transparency and mechanical strength of the product are satisfied by an improved method of blending rubbers (for example, see Patent Document 4), so-called micro-crazing occurs when subjected to impact or bending stress, and whitening occurs. The problem of coming is not solved.
[0003]
On the other hand, in sheet applications, in addition to the requirements for transparency, rigidity, impact resistance at low temperatures, and whitening resistance during bending, dust and dust in the air do not adhere and products block between products. In addition, it is required to provide a suitable surface slipperiness with durability so that the surface does not rub against other objects and be damaged, particularly at the time of sale or actual use. Such demands are usually dealt with by adding additives such as antistatic agents such as alkylamines, alkylamides, and glycerin fatty acid esters.
The effect of the antistatic agent is manifested by bleeding of the antistatic agent on the surface of the sheet, but at the time of extrusion sheet molding, the bleed antistatic agent adheres to the cooling roll, annealing roll, etc., and stains occur. Even if problems arise that the transparency of the sheet is impaired, or the sheet becomes a sheet or product, the surface is whitened (so-called bleed whitening) due to bleed of the antistatic agent on the surface and crystallization, so the appearance and printing There may be a problem that the performance is significantly impaired.
In particular, with respect to printability, the number of products that have been subjected to complex printing has increased due to the variety of products in recent years, and the printing method has been changed from silk screen printing using conventional general epoxy inks. For the purpose of increasing printing speed, offset printing using fast-drying acrylic and other UV-curable inks has come to be used, so the antistatic agent may make printability worse. . For this, anchor coating is performed before printing, restrictions are imposed on the selection of the type of antistatic agent that is difficult to deteriorate printability, and the addition amount setting is becoming more important and difficult.
[0004]
As a sheet for improving the printability of a polypropylene sheet, a sheet containing palmitic monoglyceride and stearyl monoglyceride in polypropylene has been proposed (see, for example, Patent Document 5), but this method is excellent in printability. However, depending on the product such as a highly transparent sheet, there remains a problem that bleed whitening tends to be noticeable. In addition, a sheet in which alkyl dialkanolamide or glycerin fatty acid monoester is contained in polypropylene has been proposed (see, for example, Patent Document 6). However, this method requires time for the development of antistatic performance, and sheet molding is performed. There is a problem in that the slipperiness immediately after is insufficient and the surface is easily scratched.
[0005]
On the other hand, as a polypropylene sheet with improved scratch resistance, there is a proposal of a sheet containing an antioxidant, glycerin fatty acid ester and / or fatty acid amide, and a nucleating agent in polypropylene (see, for example, Patent Document 7). However, in this proposal, although improvement of scratch resistance is recognized, the problem that takes time to develop antistatic performance still remains, and impact resistance is lowered.
[0006]
Therefore, it is not easy to satisfy the conventional polypropylene sheet with transparency, rigidity, impact resistance at low temperature, whitening resistance at the time of bending, antistatic property, and printability. At the same time, there is no polypropylene material that sufficiently satisfies the practical level.
[0007]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 60-215048
[Patent Document 2]
Japanese Patent Laid-Open No. 06-234895
[Patent Document 3]
Japanese Examined Patent Publication No. 58-25893
[Patent Document 4]
JP 57-164135 A
[Patent Document 5]
JP-A-63-145076
[Patent Document 6]
JP 7-82431 A
[Patent Document 7]
JP-A-8-134230 (Claim 2)
[0008]
[Problems to be solved by the invention]
In view of the above-mentioned problems, the object of the present invention is excellent in transparency, rigidity, impact resistance at low temperature, and whitening resistance at the time of bending, and printability including antistatic properties and recent offset printing methods. Another object of the present invention is to provide a propylene-based resin composition for forming a sheet that is excellent in durability and has a sustained effect, and a transparent sheet using the same.
[0009]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors incorporated an organic phosphate ester crystallization nucleating agent and an antistatic agent into a propylene copolymer obtained by a specific polymerization method. The present inventors have found that the above problems can be solved by using the propylene-based resin composition thus obtained, and have reached the present invention.
[0010]
  That is, according to the first invention of the present invention, 0.01 to 2.0 parts by weight of an organic phosphate ester crystallization nucleating agent and 0.01 to A propylene-based resin composition containing 2.0 parts by weight, wherein the propylene-based copolymer is a pre-stage reactor,ethyleneContent of0.5-4% By weight of propyleneethyleneCopolymer part (component A) is made of all propylene copolymer70-90% By weight, and then in the latter reactor,ethyleneContent of4-10% By weight of propylene / ethylene copolymer part (component B) of all propylene copolymer10-30Obtained by weight% production,The ethylene content of the entire propylene copolymer is 1 to 5% by weight, and the ethylene content of component B with respect to the ethylene content of component A is 1.5 times or more,And MFR of component A_ABut1-15g / 10 min, component B MFR_BBut0.1-6g / 10 min, and MFR_AMFR_BTo MFR (MFR_A/ MFR_B)But2-10Provided is a propylene-based resin composition for sheet molding, which is a copolymer.
[0014]
  In addition, the first of the present invention2According to the invention of No.1In the present invention, the organophosphate crystallization nucleating agent is bis (2,4,8,10-tetra-t-butyl-6-oxo-12H-dibenzo [d, g] [1,3,2]. Dioxaphosphocin-6-oxide) aluminum hydroxide salt or 2,2′-methylenebis (4,6-di-t-butylphenyl) sodium phosphate, a propylene-based resin for sheet molding A composition is provided.
[0015]
  In addition, the first of the present invention3According to the invention of the firstOr 2According to the invention, there is provided a propylene-based resin composition for sheet molding, wherein the antistatic agent is a glycerin fatty acid ester.
[0016]
  In addition, the first of the present invention4According to the invention,3A transparent sheet using the propylene-based resin composition for sheet molding according to any one of the inventions is provided.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a propylene-based resin composition for sheet molding in which an organic phosphate ester-based crystallization nucleating agent, an antistatic agent, and other additives as necessary are blended with a propylene-based copolymer, and the same Embodiments relating to the constituent resins, additives, sheets, and the like will be described in detail below.
[0018]
[I] Component of propylene resin composition
1. Propylene copolymer
(1) Physical properties of propylene copolymer
The propylene-based copolymer constituting the propylene-based resin composition of the present invention is a copolymer of propylene and α-olefin by multistage polymerization, and propylene is used in each polymerization step in the former reactor and the latter reactor. Is a propylene / α-olefin copolymer obtained by copolymerization in which the content of α-olefin and the constituent ratio thereof are different. The α-olefin is preferably an α-olefin having 2 to 10 carbon atoms, and examples thereof include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, etc. Among these, ethylene, 1 -Butene and 1-hexene are preferred, with ethylene being most preferred.
[0019]
In the former reactor, the content of α-olefin other than propylene is 0.1 to 5% by weight, preferably 0.5 to 4.0% by weight, more preferably 1.5 to 3.5% by weight. Propylene and propylene so that the propylene / α-olefin copolymer portion (component A) is 60 to 95% by weight, preferably 70 to 90% by weight, more preferably 70 to 80% by weight of the total polypropylene copolymer. Other α-olefins are copolymerized.
In the latter reactor, following the reaction in the former stage, the content of α-olefin other than propylene is 0.5 to 12% by weight, preferably 2 to 11% by weight, more preferably 4 to 10% by weight. Other than propylene and propylene, the α-olefin copolymer part (component B) is contained in an amount of 5 to 40% by weight, preferably 10 to 30% by weight, more preferably 20 to 30% by weight of the total polypropylene copolymer. Copolymerize with α-olefin.
Further, the α-olefin content other than propylene of component B relative to the α-olefin content other than propylene of component A is 1.5 times or more, preferably 1.8 times or more, more preferably 2 times or more. It is more preferable from the viewpoints of the balance between transparency and rigidity, impact resistance at low temperature, and sustainability of appropriate and stable antistatic performance.
Furthermore, the α-olefin content of the entire propylene copolymer is preferably 1 to 6% by weight, preferably 1 to 5% by weight, and more preferably 2 to 4.5% by weight.
[0020]
If the content of α-olefin other than propylene of component A is less than 0.1% by weight, the transparency is lowered, and if it exceeds 5% by weight, the rigidity is lowered and the durability of proper and stable antistatic performance is impaired. Therefore, it is not preferable.
If the content of α-olefin other than propylene of component B is less than 0.5% by weight, transparency and impact resistance at low temperature are insufficient, and if it exceeds 12% by weight, the rigidity is remarkably reduced, and also in production. Production efficiency is lowered, which is not preferable.
When the α-olefin content other than propylene as the component B is less than 1.5 times the α-olefin content other than the propylene as the component A, the balance between transparency, rigidity, and impact resistance at low temperatures is poor.
When the α-olefin content of the entire propylene-based copolymer is less than 1% by weight, transparency and impact resistance at low temperatures are insufficient, and when it exceeds 6% by weight, rigidity is reduced and proper and stable antistatic performance is obtained. Sustainability may be impaired.
Further, in the constitution of Component A and Component B, if Component B is less than 5% by weight, impact resistance at low temperature is insufficient, and if it exceeds 40% by weight, rigidity is lowered and proper and stable antistatic performance is sustained. This is not preferable because the properties are impaired.
[0021]
MFR of component A copolymerized in the previous reactor_AIs 20 g / 10 min or less, preferably 1 to 15 g / 10 min, more preferably 3 to 10 g / 10 min, and the MFR of Component B copolymerized in the latter reactor_BIs 0.05 to 10 g / 10 min, preferably 0.1 to 6 g / 10 min, more preferably 0.5 to 4 g / 10 min. In addition, MFR of component A_AMFR of component B of_BTo MFR (MFR_A/ MFR_B) Is 1.8 or more, preferably 2 to 10, more preferably 2.5 to 8.
MFR_AExceeds 20 g / 10 min, or MFR_BIf it exceeds 10 g / 10 min, the impact resistance at low temperatures is lowered, which is not preferable. Also MFR_BIs less than 0.05 g / 10 min, the compatibility of Component A and Component B is deteriorated, which is not preferable. MFR_AMFR_BIf the ratio is less than 1.8, it is not preferable from the viewpoint of balancing transparency, rigidity and low temperature impact resistance at a high level.
MFR_BIs the MFR of the propylene α-olefin polymer portion (component A) in the previous stage_AAnd MFR of all-propylene copolymer_TAnd the value calculated from the following correlation equation from the polymerization amount (Wb) of component B. The polymerization amount of component B is calculated from the difference between the polymerization amount in the former stage and the total polymer quantity coming out from the latter stage.
log (MFR_T) = (1−Wb / 100) × log (MFR_A) + Wb / 100 × log (MFR_B)
Here, MFR is a value measured based on JIS K7210 (1999) (230 degreeC, 21.18N load).
[0022]
2. Propylene copolymer production
As described above, the propylene-based copolymer of the present invention produces the propylene / α-olefin copolymer portion of component A in the former reactor, and then the propylene / α-olefin of component B in the latter reactor. It is a copolymer obtained by producing a copolymer portion.
Here, the pre-stage reactor and the post-stage reactor mean reactors that perform the pre-stage polymerization step and the post-stage polymerization step, respectively. The production of the propylene-based copolymer in the present invention is optional as long as it includes a pre-stage polymerization step and a post-stage polymerization step, and does not exclude the addition of other suitable steps. As a manufacturing method of the propylene-type copolymer in this invention, the following manufacturing methods can be mentioned, for example.
That is, (a) a batch polymerization is performed in a single polymerization tank, the first polymerization step is first performed, and then the second polymerization step is performed, or (b) two polymerization tanks are connected in series. A prepolymerization step is carried out in the first polymerization tank, the polymer obtained here is transferred to the second polymerization tank, and the postpolymerization process is carried out in the second polymerization tank, (c ) A further development of the above method (b), in which the pre-stage polymerization step and / or the post-stage polymerization step are performed in a plurality of polymerization tanks, (d) a method based on a combination of the methods mentioned here, etc. Can do.
Hereinafter, the catalyst, the former polymerization step, the latter polymerization step, and the transition from the former polymerization step to the latter polymerization step will be described in detail.
[0023]
(I) Catalyst
In the production of the propylene-based copolymer used in the present invention, the polymerization catalyst is not limited, and TiCl applicable to so-called stereoregular polymerization of propylene.₃Type, Magnesium-supported TiCl₄Various olefin polymerization catalysts such as metal type and metallocene type are applicable. Preferable examples include a propylene polymerization catalyst formed by combining the following catalyst components (A) and (B). Here, “combined” does not mean that the components consist only of those exemplified, and does not exclude the coexistence of the purposeful third and fourth components.
[0024]
Catalyst component (I)
The catalyst component (a) used in the production of the propylene-based copolymer used in the present invention is a solid catalyst component for stereoregular polymerization of α-olefin, which contains titanium, magnesium, halogen and an electron donor as essential components. It is. Here, “contained as an essential component” may contain other desired elements in addition to the listed three components.
The solid components themselves containing titanium, magnesium and halogen are known. For example, JP-A-53-45688, 54-31092, 54-118484, 55-90510, 55-155003, 56-18609, 56-70005, 56-72001 56-86905, 56-90807, 56-155206, 57-63310, 57-34103, 58-5309, 58-32605, 58-145707, 58-183708, 59-149905, 59-149906, 60-23404, 63-108008, 63-235307, 63-264607, JP-A-1-79203, 1-98603, 2-163104, 7-258328, 8-20607, 8-269125, It is exemplified those described in JP etc. No. 11-21309.
[0025]
Examples of the magnesium compound used as the magnesium source of the catalyst component (A) include metal magnesium, magnesium dihalide, dialkoxymagnesium, alkoxymagnesium halide, magnesium oxyhalide, dialkylmagnesium, alkylmagnesium halide, magnesium oxide, magnesium hydroxide, and magnesium. Examples thereof include carboxylates. Among these, Mg (OR such as magnesium dihalide and dialkoxymagnesium¹)_2-mX_m(Where R¹Is a hydrocarbon group, preferably having about 1 to 10 carbon atoms, X is halogen, and m is 0 ≦ m ≦ 2. ) Is preferred.
[0026]
As a titanium compound used as a titanium source, general formula Ti (OR²)_4-nX_n(Where R²Is a hydrocarbon group, preferably having about 1 to 10 carbon atoms, X is halogen, and n is 0 ≦ n ≦ 4. ). As a specific example, TiCl₄, TiBr₄, Ti (On-C₄H₉) Cl₃, Ti (On-C₄H₉)₂Cl₂, Ti (OC₂H₅) (On-C₄H₉)₂Cl, Ti (On-C₄H₉)₃Cl, Ti (OC₆H₅) Cl₃, Ti (O-i-C₄H₉)₂Cl₂, Ti (On-C₄H₉)₄, Ti (O-i-C₄H₉)₄, Etc.
[0027]
The halogen is usually supplied from the aforementioned magnesium and / or titanium halogen compounds, but other halogen sources such as Br₂, I₂, ICl₃Halogen such as, interhalogen compounds, AlCl₃, AlBr₃, AlI₃Aluminum halide such as BCl₃, BBr₃, BI₃Boron halides such as SiCl₄Silicon halides such as PCl₃, PCl₅Phosphorus halides such as WCl₆Tungsten halides such as MoCl₅It is also possible to supply from known halogenating agents such as molybdenum halides. The halogen contained in the catalyst component may be fluorine, chlorine, bromine, iodine or a mixture thereof, and chlorine is particularly preferable.
[0028]
As electron donors, oxygen-containing electron donors such as alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, acid anhydrides, Examples thereof include nitrogen-containing electron donors such as ammonia, amines, nitriles, and isocyanates, and sulfur-containing electron donors such as sulfonate esters.
More specifically, (i) alcohols having 1 to 18 carbon atoms such as ethanol, propanol, hexanol and octanol, and (b) carbon atoms having 6 to 25 carbon atoms which may have an alkyl group such as phenol, xylenol and naphthol. (C) C3-C15 ketones such as acetone, methylethylketone, methylisobutylketone, acetophenone, benzophenone, (d) C2-C15 aldehydes such as acetaldehyde, propionaldehyde, octylaldehyde, etc. , (E) ethyl acetate, cellosolve acetate, ethyl propionate, methyl butyrate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, phenyl benzoate, cellosolve benzoate, methyl toluate, toluyl Organic acid monoesters such as ethyl, ethyl ethylbenzoate, methyl anisate, ethyl ethoxybenzoate, γ-butyrolactone, or diethyl phthalate, dibutyl phthalate, diheptyl phthalate, diethyl succinate, dibutyl diisopropyl succinate, malein Dibutyl acid, diethyl 1,2-cyclohexanecarboxylate, dibutyl diisopropyl tartrate, ethylene carbonate, norbornanedienyl-1,2-dimethylcarboxylate, cyclopropane-1,2-dicarboxylic acid-n-hexyl, 1,1-cyclobutane C2-20 organic acid esters of organic acid polyvalent esters such as diethyl dicarboxylate, inorganic acid esters such as silicate esters such as (f) ethyl silicate and butyl silicate, (to) acetyl chloride , Benzoyl chloride , Acid halides having 2 to 15 carbon atoms such as toluic acid chloride, phthaloyl chloride, (thi) butyl ether, amyl ether, tetrahydrofuran, diphenyl ether, 2,2-dimethyl-1,3-dimethoxypropane, 2,2-diisopropyl Ethers having 2 to 20 carbon atoms such as -1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, Acid amides such as acetic acid amide, benzoic acid amide, toluic acid amide, (nu) diethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, amines such as tetramethylethylenediamine, (l) acetonitrile, benzo Nitrile, Tornitri Nitriles such as (E) 2- (ethoxymethyl) -ethyl benzoate, alkoxy ester compounds such as ethyl 2- (t-butoxymethyl) -benzoate, ethyl 3-ethoxy-2-phenylpropionate, ( Wa) Ketoester compounds such as ethyl 2-benzoylbenzoate, ethyl 2- (4′-methylbenzoyl) benzoate, ethyl 2-benzoyl-4,5-dimethylbenzoate, (f) methyl benzenesulfonate, benzenesulfone Sulfonic acid esters such as ethyl acrylate, ethyl p-toluenesulfonate, (yo) R³ _pR⁴ _qSi (OR⁵)_r(OR⁶)_4-pqr(Where R³And R⁴Are each a branched, cyclic or straight chain hydrocarbon group having 1 to 20 carbon atoms which may be the same or different, and R⁵Is a hydrocarbon group having 1 to 10 carbon atoms and R⁶Is a hydrocarbon group having 1 to 4 carbon atoms, p, q, and r are 1 ≦ p ≦ 2, 0 ≦ q ≦ 1, 0 ≦ r ≦ 2, and p + q + r ≦ 3, respectively. ) And the like, and the like.
Two or more kinds of these electron donors can be used. Among these, organic acid ester compounds, acid halide compounds and ether compounds, and organic alkoxysilicon compounds are preferable, and phthalic acid diester compounds, acetic acid cellosolve ester compounds, phthalic acid dihalide compounds, diether compounds, and alkoxy are particularly preferable. It is an organic alkoxy silicon compound having 2 to 3 groups.
[0029]
Further, the catalyst component (A) may be preliminarily polymerized before being subjected to polymerization, if necessary. The prepolymerization can be performed by contacting olefins, diene compounds, styrenes and the like. Specific examples of olefins used in the preliminary polymerization include those having about 2 to 20 carbon atoms, specifically, ethylene, propylene, 1-butene, 3-methylbutene-1, 1-pentene, 1-hexene, 4-methylpentene-1, 1-octene and the like. Specific examples of the diene compound include 1,5-hexadiene, 2,6-octadiene, 5-methyl-1,4-hexadiene, 1, There are 9-decadiene, p-divinylbenzene, m-divinylbenzene, o-divinylbenzene, dicyclopentadiene and the like. Specific examples of styrenes include styrene, α-methylstyrene, allylbenzene, chlorostyrene and the like. These can also be used as a mixture.
[0030]
Catalyst component (b)
The catalyst component (b) used in the production of the propylene-based copolymer used in the present invention is an organoaluminum compound. As a specific example, R⁷ _3-sAlX_sOr R⁸ _3-tAl (OR⁹)_t(Where R⁷And R⁸Is a C1-C20 hydrocarbon group or hydrogen atom, R⁹Is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen, and s and t are 0 ≦ s <3 and 0 <t <3, respectively. ) Or alumoxanes.
Specifically, (I) trialkylaluminum such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, tri-n-decylaluminum, (b) diethylaluminum monochroma Aldehyde, diisobutylaluminum monochloride, ethylaluminum sesquichloride, alkylaluminum halides such as ethylaluminum dichloride, (c) alkylaluminum hydrides such as diethylaluminum hydride, diisobutylaluminum hydride, (d) diethylaluminum ethoxide, diethylaluminum phenoxide Alkyl aluminum alkoxide, (e) methylalumoxane, butylalumo San include alumoxane and methyl isobutyl alumoxane. A plurality of these organoaluminum compounds (a) to (d) can be used.
[0031]
The ratio of the organoaluminum compound component of the catalyst component (b) and the titanium component in the solid catalyst component of the catalyst component (b) is generally Al / Ti = 1 to 1000 mol / mol, preferably Al / Ti Ti is used at a rate of 10 to 500 mol / mol.
[0032]
In addition to the catalyst components (a) and (b), an electron donating compound can be used as necessary as a catalyst component.
Examples of such electron donating compounds include compounds that can be used as essential components in component (a). Preferred electron donating compounds are diethers, inorganic acid esters, organic acid esters, and organosilicon alkoxy compounds. Particularly preferred are organosilicon alkoxy compounds represented by the following general formula and 2,2-substituted, 1 , 3-diether. Particularly preferred organosilicon alkoxy compounds include those represented by the general formula
R¹¹ _vR¹² _wSi (OR¹³)_4-v-w
(However, R¹¹Is a branched or cyclic chain hydrocarbon residue having 3 to 20, preferably 4 to 10 carbon atoms, or a cyclic aliphatic hydrocarbon residue having 5 to 20 carbon atoms, preferably 6 to 10 carbon atoms, R¹²Represents a hydrocarbon residue having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, R¹³Is an aliphatic hydrocarbon residue having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms, v is 0 ≦ v ≦ 3, w is 0 ≦ w ≦ 3 and v + w ≦ 3, respectively. Inorganic and organic silicon alkoxy compounds. In the above general formula, R¹¹Is preferably branched from a carbon atom adjacent to the silicon atom.
Examples of particularly preferred diether compounds include 2,2-dimethyl-1,3-dimethoxypropane, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane and the like.
[0033]
In the later polymerization step described later, an oxygen-containing compound or an active hydrogen-containing compound can also be used from the viewpoint of preventing stickiness. Of the active hydrogen compounds, preferred are those having a relatively low boiling point and a low odor. In particular, an alcohol having a relatively low carbon number is preferable, and methanol, ethanol, n-propyl alcohol, and i-propyl alcohol are most preferable.
[0034]
(Ii) Pre-stage polymerization step
The pre-stage polymerization step for producing the propylene / α-olefin copolymer portion of the component A of the present invention can be any as long as the propylene copolymer targeted by the present invention is obtained. For example, slurry polymerization using a hydrocarbon solvent, bulk polymerization using substantially no solvent, solution polymerization, gas phase polymerization, and the like can be given. Among these, slurry polymerization, bulk polymerization, and gas phase polymerization are preferable, and bulk polymerization and gas phase polymerization are more preferable.
The polymerization can take any form such as continuous polymerization, batch polymerization, and semi-batch polymerization. Of these, continuous polymerization is most preferable from the viewpoint of high productivity.
As the polymerization tank, any conventionally known polymerization tank can be used. That is, a tank type stirred polymerization tank, a loop type polymerization tank, a fluidized bed type polymerization tank, a stirred fluidized bed type polymerization tank, and the like can be used. As long as the component A can be produced, the polymerization vessel may be used alone, or a plurality of polymerization vessels may be connected in series and / or in parallel. Furthermore, you may use combining a polymerization tank and a classifier. In addition, when using a some polymerization tank, the polymerization conditions in each polymerization tank may be the same or different as long as the component A can be manufactured.
[0035]
As the olefin supplied to the polymerization tank, propylene and α-olefin such as ethylene, 1-butene, 1-pentene, hexene, octene and the like are used. The olefin is usually used after purification such as dehydration with a molecular sieve or the like before supplying it to the polymerization tank.
In order to control the molecular weight of the olefin polymer, various chain transfer agents are generally used. As a preferred example, hydrogen can be used. Usually, hydrogen is also purified by dehydration or deoxygenation before being supplied to the polymerization tank. There is no restriction | limiting in particular in the supply amount of hydrogen, What is necessary is just to supply the quantity of hydrogen required in order to obtain a desired molecular weight according to the property of the catalyst to be used. It is preferable to control the hydrogen supply amount by using the measured value of the hydrogen supply rate by the flow meter and the measured value of the hydrogen concentration in the polymerization tank by the process gas chromatograph in combination.
In the present invention, the polymerization temperature, polymerization pressure, average residence time and the like are not particularly limited. These can be arbitrarily set depending on the capability of the process, the performance of the catalyst, economic reasons, and the like. Generally, the polymerization temperature is about 20 to 200 ° C., preferably about 50 to 150 ° C., and the polymerization pressure is atmospheric pressure to 300 kg / cm.²G level, preferably atmospheric pressure to 100 kg / cm²About G and the average residence time are about 0.1 to 10 hours, preferably about 0.2 to 6 hours.
[0036]
(Ii) Subsequent polymerization step
The subsequent polymerization step for producing the propylene / α-olefin copolymer portion of component B of the present invention can be any as long as the propylene copolymer targeted by the present invention is obtained. For example, slurry polymerization using a hydrocarbon solvent, bulk polymerization using substantially no solvent, solution polymerization, gas phase polymerization, and the like can be given. Among these, slurry polymerization, bulk polymerization, and gas phase polymerization are preferable, and gas phase polymerization is more preferable.
The polymerization is carried out under the action of a stereoregular catalyst in the pre-stage polymerization step by supplying an olefin, optionally hydrogen, and optionally an electron donating compound to the polymerization vessel.
The polymerization can take any form such as continuous polymerization, batch polymerization, and semi-batch polymerization. Among these, batch polymerization and continuous polymerization are preferable, and continuous polymerization is most preferable in terms of high productivity.
As the polymerization tank, any conventionally known polymerization tank can be used. That is, a tank type stirred polymerization tank, a loop type polymerization tank, a fluidized bed type polymerization tank, a stirred fluidized bed type polymerization tank, and the like can be used. As long as component B can be produced, the polymerization tank may be used alone, or a plurality of polymerization tanks may be connected in series and / or in parallel. In addition, when using a some polymerization tank, the polymerization conditions in each polymerization tank may be the same or different as long as the component B can be manufactured.
[0037]
As the olefin supplied to the polymerization tank, propylene and α-olefin such as ethylene, 1-butene, 1-pentene, hexene, octene and the like are used. The olefin is usually used after purification such as dehydration with a molecular sieve or the like before supplying it to the polymerization tank.
In order to control the molecular weight of the olefin polymer obtained in the subsequent polymerization step, it is possible to use hydrogen supplementarily as in the previous step. There is no particular limitation on the supply amount of hydrogen, and a necessary amount of hydrogen may be supplied in accordance with the properties of the catalyst used and in order to achieve the molecular weight ratio with the preceding polymer. It is preferable to control the hydrogen supply amount by using the measured value of the hydrogen supply rate by the flow meter and the measured value of the hydrogen concentration in the polymerization tank by the process gas chromatograph in combination.
The weight ratio of the polymer obtained in the former polymerization step and the latter polymerization step can be arbitrarily controlled by changing the polymerization conditions in each polymerization step. Specifically, the polymerization temperature, the residence time for the reaction, the partial pressure occupied by the monomer component, and the subsequent polymerization step can be controlled by the supply amount of the electron donating compound described below.
In addition, there is no restriction | limiting in particular in the supply amount of this electron-donating compound, It can set to the range which can control suitably the polymerization amount ratio obtained by pre-stage polymerization and post-stage polymerization.
[0038]
In the present invention, the polymerization temperature, polymerization pressure, average residence time and the like are not particularly limited. These can be arbitrarily set depending on the capability of the process, the performance of the catalyst, economic reasons, and the like. Generally, the polymerization temperature is about 20 to 200 ° C., preferably about 50 to 150 ° C., and the polymerization pressure is atmospheric pressure to 300 kg / cm.²G level, preferably atmospheric pressure to 100 kg / cm²About G and the average residence time are about 0.1 to 10 hours, preferably about 0.2 to 6 hours.
[0039]
(Iv) Transition from the pre-stage polymerization process to the post-stage polymerization process
The latter polymerization step in the present invention is performed under the action of the stereoregular catalyst in the former polymerization step. Therefore, it is necessary to retain at least a part of the catalyst activity when shifting from the pre-stage polymerization step to the post-stage polymerization step.
When the present invention is carried out batchwise in a single polymerization tank, the catalyst is held in the polymerization tank throughout the entire process, so the transition from the pre-stage polymerization process to the post-stage polymerization process is the pre-stage polymerization process. After completion, the polymerization conditions can be changed by changing the polymerization conditions to those in the subsequent polymerization step.
On the other hand, if the polymerization tank in the pre-stage polymerization step is different from the polymerization tank in the post-stage polymerization step, the polymer containing the stereoregular catalyst obtained in the pre-stage polymerization step is subjected to post-stage polymerization while retaining at least part of the catalytic activity. Transfer to process.
Any method can be used for transferring the polymer. For example, a method of transferring using gravity, a method of transferring using the pressure difference between the pre-stage polymerization step and the post-stage polymerization step, a method of transferring using a pump, a method of transferring using a blower, and combinations thereof The method of use etc. can be mentioned.
It is one of the preferred embodiments of the present invention to provide a so-called degassing step for removing at least a part of the unreacted monomer in the pre-stage polymerization step during the transfer.
[0040]
2. Organophosphate crystallization nucleating agent
The organic phosphate ester crystallization nucleating agent used in the propylene polymer composition of the present invention is selected from compounds that are aromatic phosphate metal salts represented by the general formula (1) or the general formula (2). Or a mixture of two or more.
[0041]
[Chemical 1]

(Where R¹Is a divalent hydrocarbon group having 1 to 10 carbon atoms, R²And R³Is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R²And R³May be the same or different, M is a 1-3 valent metal atom, and n is an integer of 1-3. )
[0042]
[Chemical 2]

(Where R¹Is a divalent hydrocarbon group having 1 to 10 carbon atoms, R²And R³Is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and R²And R³May be the same or different, and m is 1 or 2. )
[0043]
Specific examples of the compound represented by the general formula (1) include sodium-2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2′-ethylidene- Bis (4,6-di-t-butylphenyl) phosphate, lithium-2,2′-methylene-bis- (4,6-di-t-butylphenyl) phosphate, lithium-2,2′-ethylidene -Bis (4,6-di-t-butylphenyl) phosphate, sodium-2,2'-ethylidene-bis (4-i-propyl-6-t-butylphenyl) phosphate, lithium-2,2 ' -Methylene-bis (4-methyl-6-t-butylphenyl) phosphate, lithium-2,2'-methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, Thorium-2,2′-butylidene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2′-butylidene-bis (4,6-di-t-butylphenyl) phosphate, sodium 2,2′-t-octylmethylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2′-t-octylmethylene-bis (4,6-di-t-butylphenyl) phosphate Fate, calcium-bis- (2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate), magnesium-bis [2,2′-methylene-bis (4,6-di-) t-butylphenyl) phosphate], barium-bis [2,2′-methylene-bis (4,6-di-t-butylphenyl) phosphate], sodium-2,2 -Methylene-bis (4-methyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylene-bis (4-ethyl-6-t-butylphenyl) phosphate, sodium-2,2 ' -Ethylidene-bis (4-m-butyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylene-bis (4,6-di-methylphenyl) phosphate, sodium-2,2 ' -Methylene-bis (4,6-di-ethylphenyl) phosphate, potassium-2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate, calcium-bis [2,2 ' -Ethylidene-bis (4,6-di-t-butylphenyl) phosphate], magnesium-bis [2,2'-ethylidene-bis (4,6-di-t- Butylphenyl) phosphate], barium-bis [2,2′-ethylidene-bis (4,6-di-t-butylphenyl) phosphate], aluminum-tris [2,2′-methylene-bis (4 6-di-t-butylfell) phosphate] and aluminum-tris [2,2′-ethylidene-bis (4,6-di-t-butylphenyl) phosphate], among which sodium- 2,2′-ethylidene-bis (4,6-di-t-butylphenyl) phosphate is preferred.
[0044]
The compound represented by the general formula (2) is R²And R³Are preferably t-butyl groups, and specific examples thereof include bis (2,4,8,10-tetra-t-butyl-6-oxo-12H-dibenzo [d, g] [1,3 , 2] dioxaphosphocin-6-oxide) aluminum hydroxide salt.
[0045]
The compounding amount of the organic phosphate ester crystallization nucleating agent is 0.01 to 2.0 parts by weight, preferably 0.05 to 1.0 parts by weight, particularly preferably 100 parts by weight of the propylene polymer. 0.1 to 0.3 parts by weight. If the blending amount is less than this range, the intended transparency improving effect is not obtained. Conversely, if it exceeds this range, the transparency improving effect according to the blending amount is saturated and it is not economical.
[0046]
3. Antistatic agent
Examples of the antistatic agent used in the propylene polymer composition of the present invention include nonionic antistatic agents, cationic antistatic agents, zwitterionic antistatic agents, and anionic antistatic agents.
[0047]
Nonionic antistatic agents include glycerin fatty acid ester, sorbitan fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, fatty acid diethanolamide, polyoxyalkylene alkyl ether, polyoxyalkylene alkylphenyl ether, polyoxyethylene- Examples include polyoxypropylene alkyl ethers and ethylene oxide adducts of fatty acids.
[0048]
Examples of glycerin fatty acid esters include glycerin monocaprylate, glycerin monolaurate, glycerin monomyristic ester, glycerin monopalmitate, glycerin monostearate, glycerin monooleate, glycerin monobehenate, glycerin monobehenate. Monoglycerin fatty acid esters such as erucic acid ester, diglycerin monobehenic acid ester, diglycerin monostearic acid ester, diglycerin monooleic acid ester, diglycerin monopalmitic acid ester, diglycerin monomyristic acid ester, diglycerin monolaurin Examples include diglycerin fatty acid esters such as acid esters.
[0049]
Sorbitan fatty acid ester is a monoester or triester of fatty acid and sorbitan which is a kind of polyhydric alcohol.
The polyoxyethylene alkylamine is obtained by reacting ethylene oxide with two active hydrogens of a higher alkylamine such as laurylamine, and adding ethylene oxide to one or two of hydrogen bonded to nitrogen.
Polyoxyethylene alkylamide is obtained by addition polymerization of ethylene oxide to higher fatty acid amide or dehydration condensation of higher fatty acid amide and polyethylene glycol.
Examples of the fatty acid diethanolamide include lauric acid diethanolamide, palmitic acid diethanolamide, and stearic acid diethanolamide.
Specific examples of polyoxyalkylene alkyl ethers include polyoxyethylene alkyl ethers, which are obtained by addition polymerization of ethylene oxide to C12-C22 higher aliphatic alcohols such as lauryl, cetyl, and oleyl alcohol. can get.
Specific examples of the polyoxyalkylene alkylphenyl ether include polyoxyethylene alkylphenyl ether, which can be obtained by addition polymerization of ethylene oxide to alkylphenol or alkylnaphthol.
[0050]
Among the nonionic antistatic agents, a glycerin fatty acid ester is preferable, and a glycerin fatty acid ester having a monoester content of 50% by weight or more is particularly preferable. Most preferably, the active ingredient is glycerol monopalmitate, glycerol monostearate, glycerol monooleate, or glycerol monoerucate.
[0051]
Furthermore, examples of the zwitterionic antistatic agent include alkylbetaine type, examples of the cationic antistatic agent include quaternary ammonium chloride, and examples of the anionic antistatic agent include alkyl sulfonate. However, a more preferable antistatic agent from the viewpoint of antistatic performance, roll stain resistance, and printability is a nonionic antistatic agent.
[0052]
The blending amount of the antistatic agent is 0.01 to 2.0 parts by weight, preferably 0.02 to 0.5 parts by weight, particularly preferably 0.03 to 0. 0 parts by weight with respect to 100 parts by weight of the propylene polymer. 3 parts by weight. If the blending amount is less than this range, the desired antistatic performance and surface slippery effect cannot be obtained with sustainability. Conversely, if the blending amount exceeds this range, the surface will bleed and problems such as poor appearance are likely to occur. .
[0053]
4). Other ingredients
In the propylene-based resin composition of the present invention, additives other than those described above can be formulated as necessary as long as the object of the present invention is not impaired. For example, a phenol-based antioxidant and / or Phosphorous antioxidants, neutralizers, weathering agents, ultraviolet absorbers, light stabilizers, lubricants, molecular weight modifiers (peroxides), colorants, various auxiliaries such as various fillers, propylene alone or other α- Copolymer with olefin, other thermoplastic resins such as low-density polyethylene and high-density polyethylene, various thermoplastic elastomers, and at least one additive selected from inorganic or organic fillers, and propylene resin for sheet molding It can be a composition.
[0054]
[II] Production of propylene-based resin composition
The propylene-based resin composition of the present invention can be obtained by mixing the above-mentioned propylene-based copolymer with an organic phosphate ester-based crystallization nucleating agent and an antistatic agent, and if necessary, other amounts of other components. For these mixing, for example, a normal mixing device such as a mixer with a high-speed stirrer such as a Henschel mixer or a super mixer, a ribbon blender, or a tumbler can be used, and after mixing, by pelletizing with an extruder or kneader, It can be set as a propylene-type resin composition.
[0055]
[III] Sheet
The sheet of the present invention can be produced by using the above-described propylene-based resin composition by a known molding method, for example, an extrusion molding method, a calendar molding method, a compression molding method, a cast molding method, or the like. The extrusion molding method is preferable, and examples of the extrusion molding method include a T-die method and an inflation method. The extruded sheet is cooled and solidified by a known method such as a polishing roll method, an air knife method, or a metal mirror belt method. The layer structure may be a single layer or a multilayer including at least one composition layer of the present invention.
The extrusion temperature is preferably from 180 to 260 ° C, more preferably from 180 to 240 ° C in terms of the transparency and formability of the sheet. If the extrusion temperature is 180 ° C. or higher, it is sufficiently melted, and if it exceeds 260 ° C., thermal deterioration tends to occur, which is not preferable.
[0056]
The sheet of the present invention is excellent in transparency and has a haze of preferably 15% or less, more preferably 1 to 10%. Moreover, there is little decrease in transparency in the sheet after storage.
The thickness of the transparent sheet of the present invention is not particularly limited, but it is usually preferably 0.10 to 3.0 mm, particularly 0.15 to 2.0 mm for stationery use.
In addition, the transparent sheet of the present invention may be subjected to surface treatment such as corona discharge treatment, flame treatment, plasma treatment, ozone treatment, etc., which are usually employed industrially, as long as the object of the present invention is not impaired. Is possible. In addition, the transparent sheet of the present invention can be coated with or affixed with a modifier on the surface.
[0057]
The sheet of the present invention is excellent in transparency, rigidity, impact resistance at low temperature, and whitening resistance at the time of bending, and is excellent in printability including antistatic properties and recent offset printing methods, and further effects thereof. Therefore, it can be suitably used for stationery sheets, packaging cases for magnetic recording media, and the like. Examples of the stationery include a file case and a binder, and examples of the magnetic recording medium packaging case include a video cassette and DVD packaging case.
[0058]
【Example】
Hereinafter, the present invention will be specifically described with reference to examples. However, the scope of the present invention is not limited to the examples. The detailed description of the invention and the measurement of each item in the examples were carried out by the following methods.
(1) MFR (melt flow rate): The MFR of the propylene copolymer and the propylene resin composition is the melt flow rate (temperature 230 ° C., load 21.18 N) of JIS-K7210 (1999) “polypropylene test method”. Measured according to
In addition, MFR of component B_BIs the MFR of component A obtained in the previous polymerization step, as shown in the previous equation._AAnd MFR measured after completion of the latter polymerization step_TAnd production ratio of component A; W_A% By weight, production ratio of component B; W_BFrom the weight percentage, MFR of component B according to the following formula:_BIt was determined.
log (MFR_A) X W_A/ 100 + log (MFR_B) X W_B/ 100 = log (MFR_T)
(2) Ethylene content: The ethylene content of component B is the ethylene content measured after completion of polymerization of component A in the preceding polymerization step; E_AAnd ethylene content measured after completion of polymerization in the latter stage polymerization step; E_TOTALAnd production ratio of component A; W_A% By weight, production ratio of component B; W_BFrom wt%, the ethylene content of component B according to the formula: E_BIt was determined. The ethylene content is¹³Obtained by C-NMR.
E_A× W_A/ 100 + E_B× W_B/ 100 = E_TOTAL
(3) Metal roll contamination: The degree of contamination of the cooling metal roll was visually observed during extrusion sheet molding, and judged according to the following criteria.
○: No dirt.
Δ: Slightly stained.
X: Significant contamination occurs.
(4) Transparency: HAZE was evaluated according to JIS-K7136-2000.
One day after the sheet was formed, HAZE was measured to obtain HAZE1, and the sheet was stored at a temperature of 40 ° C. for 14 days, and then HAZE was measured. This HAZE value was designated as HAZE2. The larger the value of the change in HAZE (HAZE2-HAZE1), the better the surface appearance deteriorated.
(5) Tensile modulus: The tensile modulus of the extruded sheet was evaluated according to JIS-K7127-1999.
(6) DuPont impact strength: The DuPont impact strength of the extruded sheet was evaluated with a DuPont impact strength measuring machine manufactured by Toyo Seiki Seisakusho, in accordance with ASTM-D2794.
(7) Bending whitening resistance: The extruded sheet was bent at 180 degrees, and the whitening property of the bent part was visually observed and judged according to the following criteria.
○: not whitened.
Δ: Slightly whitened.
X: Remarkably whitened.
(8) Antistatic property (electrostatic voltage decay half-life): One day after extrusion sheet forming, charged to static static meter (manufactured by Shido Static Electric Co., Ltd.), charged for 10 kv for 2 minutes, and measured for half-life after stopping charging. . The smaller this value (second), the better the antistatic property.
(9) Printability: The extruded sheet was printed using an RI tester (printing ink used was Toyo Ink's flash dry FDO-G black), and 10 cm under an 80 W / cm high-pressure mercury lamp was 24 cm / min. UV curing was carried out by passing 10 times at a speed of 5 mm. The printed sheet was visually observed for coloring to determine the colorability.
○: Vividly colored.
Δ: Coloring is slightly light.
X: Remarkably light coloring.
[0059]
Example 1
(1) Production of propylene copolymer
(I) Production of solid catalyst
Diethoxymagnesium (hereinafter referred to as Mg (OEt)) is added to a 100 liter reactor equipped with a stirring blade, thermometer, jacket, and cooling coil.₂. ): 30 mol charged, then tetrabutoxy titanium (hereinafter referred to as Ti (OBu))₄. ), Mg (OEt) charged₂Ti (OBu) for Mg₄/Mg=0.60 (molar ratio). Furthermore, 19.2 kg of toluene was charged, and the temperature was raised while stirring. After reacting at 139 ° C. for 3 hours, the temperature was lowered to 130 ° C. and methyltriphenoxysilane (hereinafter, MeSi (OPh)₃. ) In toluene solution previously charged with Mg (OEt)₂MeSi (OPh) for magnesium₃/Mg=0.67 (molar ratio). The amount of toluene used here was 7.8 kg. After the addition was completed, the reaction was performed at 130C for 2 hours, and then the temperature was lowered to room temperature, and tetraethoxysilane (hereinafter referred to as Si (OEt)).₄. ) Was added. Si (OEt)₄The amount of addition of Mg (OEt) previously charged₂Si (OEt) against magnesium in₄/Mg=0.056 (molar ratio).
Next, toluene was added to the obtained reaction mixture so that the magnesium concentration was 0.58 mol / L-toluene. Further, diethyl phthalate (hereinafter referred to as DEP) was charged with Mg (OEt) previously charged.₂It added so that it might become DEP / Mg = 0.10 (molar ratio) with respect to magnesium in. The resulting mixture was cooled to 10 ° C. with continued stirring, and titanium tetrachloride (hereinafter referred to as TiCl).₄. ) Was added dropwise over 2 hours to obtain a homogeneous solution. TiCl₄Is the previously charged Mg (OEt)₂TiCl for magnesium in₄/Mg=4.0 (molar ratio). TiCl₄After completion of the addition, the temperature was raised to 15 ° C. at 0.5 ° C./min with stirring, and kept at the same temperature for 1 hour. Next, the temperature was raised again to 50 ° C. at 0.5 ° C./min, and kept at the same temperature for 1 hour. Further, the temperature was raised to 118 ° C. at 1 ° C./min, and the treatment was performed at the same temperature for 1 hour. After completion of the treatment, stirring was stopped and the supernatant liquid was removed, followed by washing with toluene so that the residual liquid ratio = 1/73 (weight ratio) to obtain a slurry.
Next, the slurry obtained here was mixed with toluene and TiCl at room temperature.₄Was added. TiCl₄Is the previously charged Mg (OEt)₂TiCl for magnesium in₄/ Mg (OEt)₂= 5.0 (molar ratio). Toluene is TiCl₄The concentration was adjusted to 2.0 mol / L-toluene. The slurry was heated with stirring and reacted at 118 ° C. for 1 hour. After completion of the reaction, stirring was stopped and the supernatant liquid was removed, followed by washing with toluene so that the residual liquid ratio = 1/150 (weight ratio) to obtain a solid component slurry.
[0060]
(Ii) Production of solid catalyst component (A)
400 g of the obtained solid component was transferred to another reactor having a stirring blade, a thermometer, and a cooling jacket, and diluted with normal hexane to a solid component concentration of 5.0 g / l. did. While stirring the resulting slurry, trimethylvinylsilane, triethylaluminum (hereinafter referred to as TEA) and tertiary butylmethyldiethoxysilane (hereinafter referred to as TBMDES) were added at 15C. The addition amounts of TEA, trimethylvinylsilane, and TBMDES were 3.1 mmol, 0.2 ml, and 0.2 ml, respectively, with respect to 1 g of the solid component in the solid catalyst component (A). After completion of the addition, the mixture was kept at 15 ° C. for 1 hour with continuous stirring, further heated to 30 ° C., and stirred at the same temperature for 2 hours. Next, the temperature was lowered again to 15 ° C., and while maintaining the same temperature, 4.8 kg of propylene gas was fed into the reactor at a constant rate over 8 hours to carry out prepolymerization. After completion of the feed, stirring was stopped and the supernatant liquid was removed, followed by washing with normal hexane to obtain a slurry of the solid catalyst component (A). The remaining liquid ratio was 1/12 (weight ratio). The obtained solid catalyst component (A) had 11.5 g of propylene polymer per 1 g of the solid catalyst component (A).
[0061]
(Iii) Production of propylene-ethylene copolymer
Internal volume 0.4m³Liquid phase polymerization tank with stirring device 1, 0.5m³Propylene-ethylene copolymer was continuously produced by a process incorporating a degassing system comprising a double-pipe heat exchanger and a fluidized flash tank between the stirred gas phase polymerization tanks 2.
Liquid phase polymerization tank 1 was continuously fed with liquefied propylene, ethylene, hydrogen, TEA, and TBEDMS. The feed amounts of liquefied propylene, TEA, and TBEDMS are 163 kg / hr, 22.1 g / hr, 1.91 g / hr, hydrogen has a gas phase concentration of 2.38 mol%, and ethylene has a gas phase. Was fed to a concentration of 1.55 mol%. Furthermore, the solid catalyst component (A) obtained in the above (ii) was fed as a solid component contained in (A) so as to be 0.13 g / hr. Further, the polymerization tank was cooled so that the polymerization temperature became 70 ° C.
The slurry polymerized in the polymerization tank 1 was heated by a double pipe heat exchanger and extracted into a fluidized flash tank. The slurry extraction rate was adjusted to about 24 kg / hr as polypropylene particles contained in the slurry. The average residence time of the polypropylene particles in the liquid phase polymerization tank 1 was 1.4 hours. In the fluidized flash tank, the temperature in the tank was maintained at 70 ° C. while feeding propylene gas heated from below. When the polypropylene extracted from the fluid flash tank as a small sample was analyzed, the MFR was 3.5 g / 10 min and the ethylene content was 3.0% by weight. The solid polypropylene particles obtained here were sent to the gas phase polymerization tank 2 and further copolymerized with ethylene and propylene.
For ethylene and propylene, the sum of the partial pressures of ethylene and propylene is 17.0 kgf / cm.²G was fed so that the mole fraction of ethylene was constant at 4.1 mol%. Hydrogen was fed so that the hydrogen concentration was 0.75 mol%. The polymerization temperature was 75 ° C., and the extraction rate of the propylene / ethylene block copolymer extracted from the gas phase polymerization tank 2 was adjusted to be about 33 kg / hr. The average residence time in the gas phase polymerization tank 2 was 1.7 hr. When the polymer particles extracted from the gas phase polymerization tank 2 were analyzed, the MFR was 2.7 g / 10 minutes and the ethylene content was 4.0% by weight. From these results, the polymerization amount ratios of the first and second stages are 75% by weight and 25% by weight, respectively, and the MFR and ethylene content of the ethylene-propylene copolymer produced by the second stage polymerization are: They were found to be 1.2 g / 10 min and 7% by weight, respectively. The above polymerization conditions and polymerization results are shown in Table 1.
[0062]
(2) Production of propylene-based resin composition
To 100 parts by weight of the propylene copolymer powder obtained above, bis (2,4,8,10-tetra-t-butyl-6-oxo-12H-dibenzo [ d, g] [1,3,2] dioxaphosphocin-6-oxide) aluminum hydroxide salt (trade name: Mark NA21 manufactured by Adeka Co., Ltd., described as “NA21” in the table) 0.2 parts by weight As an antistatic agent, 0.07 part by weight of glycerin monostearate (trade name: electro stripper TS5 manufactured by Kao Corporation, described as “TS5” in the table), 0.03 part by weight of calcium stearate, trade name Add 0.2 parts by weight of Irganox 1010 (Ciba Geigy), mix with a Henschel mixer, melt knead at 250 ° C., and adjust the MFR to 2.6 g / 10 min. To obtain a pyrene-based resin composition. The contents of the composition obtained are shown in Table 2.
[0063]
(3) Sheet manufacturing
This propylene-based resin composition was extruded from a coat hanger die having a die width of 500 mm with an extrusion sheet molding machine heated to 230 ° C. and having a screw diameter of 50 mm. After sandwiching and cooling and solidifying, an extruded sheet having a surface tension of 45 dynes and a thickness of 0.6 mm was produced while applying surface treatment with a corona discharge treatment machine. The obtained sheet was evaluated. The results are shown in Table 2.
[0064]
Examples 2-4
The polymerization conditions for the first and second stages in (iii) of Example 1 were adjusted as shown in Table 1, and the propylene copolymers shown in Table 1 were obtained. Using these propylene copolymers, the production of propylene resin compositions and sheet molding were performed and evaluated in the same manner as in Example 1. The obtained results are shown in Table 2.
[0065]
Comparative Examples 1-5
The polymerization conditions for the first and second stages in (iii) of Example 1 were adjusted as shown in Table 1, and the propylene block copolymers shown in Table 1 were obtained. Using these propylene block copolymers, in the same manner as in Example 1, production of propylene resin compositions and sheet molding were performed and evaluated. The obtained results are shown in Table 2.
[0066]
[Table 1]

[0067]
[Table 2]

[0068]
The compounds other than NA21 and TS5 in Table 2 are as follows.
Gerol MD (trade name): 1,3,2,4-di (paramethylbenzylidene) -sorbitol manufactured by Shin Nippon Rika Co., Ltd.
A4085 (trade name): ethylene-butene-random copolymer elastomer manufactured by Mitsui Chemicals, Inc.
[0069]
As is clear from Table 2, the sheet from the propylene-based resin composition of the present invention is excellent in elastic modulus, transparency, impact resistance at low temperature, and whitening resistance during bending, and has antistatic properties and printing. (Examples 1 to 4). On the other hand, in the composition of the copolymer only by the one-stage polymerization process, the antistatic property is inferior (Comparative Example 1). In the composition in which the ethylene-butene copolymer elastomer is blended with the copolymer by the one-stage polymerization process, It is inferior in whitening and antistatic properties (Comparative Example 2), and is poor in transparency in the composition of the copolymer only by a single-stage polymerization process having a high ethylene content (Comparative Example 3). When a nucleating agent other than the nucleating agent was used, there was metal roll contamination (Comparative Example 4), and the copolymer composition in which the amount of propylene / ethylene copolymer produced in the previous reactor was too high was inferior in impact strength. (Comparative Example 5).
[0070]
【The invention's effect】
The polypropylene resin composition for sheet molding of the present invention is excellent in transparency, rigidity, impact resistance at low temperature, whitening resistance when bent, and in antistatic properties and printability. It is suitable for use in transparent sheets such as sheets.

Claims (4)

Propylene resin composition containing 0.01 to 2.0 parts by weight of an organic phosphate crystallization nucleating agent and 0.01 to 2.0 parts by weight of an antistatic agent with respect to 100 parts by weight of a propylene copolymer. The propylene-based copolymer is a reactor in the previous stage, and the propylene / ethylene copolymer portion (component A) having an ethylene content of 0.5 to 4 % by weight is converted into the total propylene-based copolymer. 70-90% by weight is produced, subsequently, 10 to 30 weight in subsequent reactors, propylene-ethylene copolymer portion of the content of ethylene is 4-10 wt% (component B) the total propylene copolymer % , The ethylene content of the total propylene copolymer is 1 to 5% by weight, the ethylene content of component B is 1.5 times or more of the ethylene content of component A , and component A of MFR _a 1 to 15 / 10 min, and wherein the MFR _B is 0.1 to 6 g / 10 min Component B, and the ratio MFR _B of _{MFR A (MFR A / MFR B} ) is a copolymer which is a 2-10 A propylene-based resin composition for sheet molding. Organophosphate crystallization nucleating agent is bis (2,4,8,10-tetra-t-butyl-6-oxo-12H-dibenzo [d, g] [1,3,2] dioxaphosphocin The propylene for sheet molding according to claim 1 , which is a 6-oxide) aluminum hydroxide salt or 2,2'-methylenebis (4,6-di-t-butylphenyl) sodium phosphate. -Based resin composition. The propylene resin composition for sheet molding according to claim 1 or 2 , wherein the antistatic agent is a glycerin fatty acid ester. The transparent sheet which uses the propylene-type resin composition for sheet shaping | molding of any one of Claims 1-3 .