JP4722330B2 - Polyolefin resin composition - Google Patents

Description

【０００６】
（式中、Ｒ¹は直接結合、硫黄原子又は炭素数１〜９のアルキレン基若しくはアルキリデン基を示し、Ｒ²，Ｒ³，Ｒ⁴及びＲ⁵は水素原子又は炭素数１〜８のアルキル基を示し、Ｍ¹は１〜３価の金属原子を示し、ｎはＭ¹の価数である。）
で表される環状リン酸エステル化合物及び（Ｃ）一般式（４）
（ＲＣＯＯ）_mＭ² ・・・（４）
（式中、Ｒは炭素数が８〜２３で、炭素−炭素不飽和結合の数が３以下の不飽和又は飽和炭化水素残基を示し、Ｍ²は周期律表第２，３，１２又は１３族の金属元素を示し、ｍはＭ²の価数である。）
で表される金属石鹸を配合してなるポリオレフィン系樹脂組成物であって、前記（Ａ）成分のポリオレフィン樹脂が一種単独のポリエチレン又はポリプロピレンであり、蛍光Ｘ線法により検出される（Ａ）成分中の残留塩素濃度をＸ（重量ｐｐｍ）、該組成物中の（Ｂ）成分の濃度をＹ（重量ｐｐｍ）、（Ｃ）成分の濃度をＺ（重量ｐｐｍ）及び（Ｃ）成分の分子量をＢとしたときに、下記式
（Ｘ×Ｂ）／７１≦Ｚ＜２Ｙ
を満たし、かつ（Ｂ）成分の含有量が、ポリオレフィン系樹脂組成物中２００〜２０００重量ｐｐｍであることを特徴とするポリオレフィン系樹脂組成物を提供するものである。
【０００７】
【発明の実施の形態】
本発明で用いる（Ａ）成分のポリオレフィン樹脂は、チーグラー系触媒を用いて製造されたものを用いる。チーグラー触媒は、例えば遷移金属ハライドとアルミニウム，アルカリ土類金属もしくはアルカリ金属などのアルキル化物とを組合せた触媒であり、（Ａ）成分のポリオレフィン樹脂としては、このような触媒を用いて公知の方法により製造ものを用いることができる。ポリオレフィン樹脂としては、ポリエチレン又はポリプロピレンである。これらは、一種単独で用いられる。
ポリオレフィン樹脂中の残留塩素濃度は、蛍光Ｘ線法により測定する。測定には、通常の蛍光Ｘ線分析装置を使用することができる。
本発明で用いる（Ｂ）成分の環状リン酸エステル化合物は、一般式（１）、（２）又は（３）
【０００８】
【化３】

【０００９】
（式中、Ｒ¹ は直接結合、硫黄原子又は炭素数１〜９のアルキレン基若しくはアルキリデン基を示し、Ｒ² ，Ｒ³ ，Ｒ⁴ 及びＲ⁵ は水素原子又は炭素数１〜８のアルキル基を示し、Ｍ¹ は１〜３価の金属原子を示し、ｎはＭ¹ の価数である。
）
で表されるものである。Ｒ¹ としてはメチレン基が好ましく、Ｒ² ，Ｒ³ ，Ｒ⁴ 及びＲ⁵ としてはｔ−ブチル基が好ましく、Ｍ¹ としてはナトリウム，リチウム，カリウム，マグネシウム及びアルミニウムが好ましい。
一般式（１）で表される環状リン酸エステル化合物としては、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、カルシウムビス〔２，２’−チオビス（４−メチル−６−ｔ−ブチルフェニル）フォスフェート〕、カルシウムビス〔２，２’−チオビス（４−エチル−６−ｔ−ブチルフェニル）フォスフェート〕、カルシウムビス〔２，２’−チオビス（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’−チオビス（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’−チオビス（４−ｔ−オクチルフェニル）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（４，４’−ジメチル−６，６’−ジ−ｔ−ブチル−２，２’−ビフェニル）フォスフェート、カルシウムビス〔（４，４’−ジメチル−６，６’−ジ−ｔ−ブチル−２，２’−ビフェニル）フォスフェート〕、ナトリウム−２，２’−エチリデンビス（４−ｓ−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）フォスフェート〕、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−ブチルフェニル）フォスフェート〕、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〕及び下記式で示されるもの等が挙げられる。
【００１０】
【化４】

【００１１】
一般式（２）で表される環状リン酸エステル化合物としては、下記式で示されるもの等が挙げられる。
【００１２】
【化５】

【００１３】
一般式（３）で表される環状リン酸エステル化合物としては、下記式で示されるもの等が挙げられる。環状リン酸エステル化合物は、一種単独で用いてもよいし、二種以上を組み合わせて用いてもよい。
【００１４】
【化６】

【００１５】
本発明のポリオレフィン系樹脂組成物において、環状リン酸エステル化合物の含有量は１００〜５０００ｐｐｍであるが、２００〜２０００ｐｐｍが好ましい。環状リン酸エステル化合物が１００ｐｐｍ未満であると、十分な造核効果を得ることができず、また、５０００ｐｐｍを超えても、添加量に見合う効果が得られるものではなく、コスト高となってしまう。
本発明で用いる（Ｃ）成分の金属石鹸は、一般式（４）
（ＲＣＯＯ）_m Ｍ² ・・・（４）
（式中、Ｒは炭素数が８〜２３で、炭素−炭素不飽和結合の数が３以下の不飽和又は飽和炭化水素残基を示し、Ｍ² は周期律表第２，３，１２又は１３族の金属元素を示し、ｍはＭ² の価数である。）
で表されるものである。一般式（４）において、Ｒの炭素数が８未満であると、ポリオレフィン樹脂との相溶性が不良であって、その滲出によりポリオレフィン製品の表面がべたつくという問題が生じる。Ｒの炭素数が２３を超えると、炭素数の増大と共に効果が急激に低下する。また、炭素−炭素不飽和結合の数が３を超えると、熱劣化防止効果が低下する。Ｍ² が周期律表第１，１１族の金属元素であると、金属石鹸の水溶性が大きくなり、好ましくない。Ｍ² が周期律表第４〜１０族又は第１４族以上の金属元素、例えば鉄、コバルト又はニッケル等であると、金属石鹸をポリオレフィン樹脂に配合したときにポリオレフィン樹脂の劣化を促進して、その機械的強度を低下させたり、劣化により退色を引き起こすので不適当である。なお、一つの金属石鹸においてｍ個の脂肪酸部分は同一であっても異なっていてもよい。
好ましい脂肪酸としては、ラウリル酸（ｎ−Ｃ₁₁Ｈ₂₃；Ｒを示す、以下同様）、ミリスチン酸（ｎ−Ｃ₁₃Ｈ₂₇），パルミチン酸（ｎ−Ｃ₁₅Ｈ₃₁），ステアリン酸（ｎ−Ｃ₁₇Ｈ₃₅），オレイン酸（ｎ−Ｃ₁₇Ｈ₃₂），リノール酸（ｎ−Ｃ₁₇Ｈ₃₀），リノレイン酸（ｎ−Ｃ₁₇Ｈ₂₈）が挙げられる。また、Ｍ² としては、ベリリウム，マグネシウム，カルシウム，亜鉛，アルミニウムなどが挙げられ、本発明においてはカルシウムが好ましい。金属石鹸は、一種単独で用いてもよいし、二種以上を組み合わせて用いてもよい。
【００１６】
本発明において、（Ｃ）成分の金属石鹸は、蛍光Ｘ線法により検出される（Ａ）成分中の残留塩素濃度をＸ（重量ｐｐｍ）、該組成物中の（Ｂ）成分の濃度をＹ（重量ｐｐｍ）、（Ｃ）成分の濃度をＺ（重量ｐｐｍ）及び（Ｃ）成分の分子量をＢとしたときに、下記式
（Ｘ×Ｂ）／７１≦Ｚ＜２Ｙ
を満たす量を配合する。Ｚが（Ｘ×Ｂ）／７１未満であると、ポリオレフィン樹脂中の残留塩素と（Ｂ）成分の環状リン酸エステル化合物が反応してしまう。また、Ｚが２Ｙ以上であると、金属石鹸と環状リン酸エステル化合物が反応してしまい、環状リン酸エステルの添加効果が低下してまう。
本発明のポリオレフィン系樹脂組成物には、上記必須成分に加え、必要に応じて各種の添加剤、例えば酸化防止剤、無機系充填剤、紫外線吸収剤、耐候剤などを添加してもよい。また、本発明のポリオレフィン系樹脂組成物は、上記必須成分及びその他の添加成分を、公知の方法で混合することにより製造することができる。
本発明のポリオレフィン系樹脂組成物は、各種射出成形品やシートの成形に用いることができる。
【００１７】
【実施例】
次に、本発明を実施例によりさらに詳細に説明するが、本発明はこれらの例によってなんら限定されるものではない。
実施例１〜６，比較例１〜１０
（１）ポリプロピレンの製造
（固体触媒成分の調製）
窒素で置換した内容積５リットルの攪拌機付きの三つ口フラスコに、脱水処理したヘプタン６００ミリリットル、ジエトキシマグネシウム１６０ｇを加えた。４０℃に加熱し、四塩化ケイ素２４ミリリットルを加えて２０分間攪拌した後、フタル酸ジエチル２３ミリリットルを添加した。この溶液を８０℃まで昇温し、引き続き四塩化チタンを７７０ミリリットル滴下し、内温１１０℃で、２時間攪拌した。その後、攪拌を停止して固体を沈降させ、上澄みを抜き出した。９０℃の脱水ヘプタンを用いて７回洗浄を行なった。次に、四塩化チタンを１２２０ミリリットル加え、内温１１０℃で、２時間攪拌した。その後、攪拌を停止して固体を沈降させ、上澄みを抜き出した。６０℃の脱水ヘプタンによる洗浄を７回繰り返し、固体触媒成分を得た。
（予備重合触媒の調製）
窒素で置換した内容積１リットルの攪拌機付きの三つ口フラスコに、上記固体触媒成分４８ｇと脱水ヘプタン４００ミリリットルを添加した。４０℃に昇温し、トリエチルアルミニウム2.０ミリリットルとジシクロペンチルジメトキシシラン6.３ミリリットルを加えた。その後、プロピレンガスを流通させ、２時間反応させた。その後、脱水ヘプタンを用いて十分に洗浄を行い、予備重合触媒を得た。
（ポリプロピレンの製造）
十分に乾燥させた内容積５リットルの、投入管付きステンレス鋼製オートクレーブに脱水ヘプタン１８００ミリリットル、トリエチルアルミニウム１０ミリモル、ジシクロペンチルジメトキシシラン1.２５ミリモルを加え、８０℃に昇温し、分圧が0.２ＭＰａ・Ｇとなるように水素を導入し、その後、プロピレンを導入して全圧を0.８ＭＰａ・Ｇとした。投入管に脱水ヘプタン１００ミリリットル、チタン換算で0.１ミリモルの予備重合触媒を入れ、圧バランスによりオートクレーブ内に導入した。全圧が0.８ＭＰａ・Ｇとなるようにプロピレンを導入しながら、１時間重合を行なった。その後、降温し、脱圧し、内容物をろ過し、真空乾燥させて無脱灰のポリプロピレン（ＰＰ）を得た。後述する方法によりＰＰ中の塩素濃度を測定したところ、８０ｐｐｍであった。
（塩素濃度の調整）
上記と同様にしてプロピレンを１時間重合した後、降温し、脱圧し、内容物をメタノール中に投入し、ろ過し、真空乾燥させて塩素濃度を調整したＰＰを得た。
【００１８】
（２）高密度ポリエチレンの製造
（固体触媒成分の調製）
窒素で置換した内容積５リットルの攪拌機付き反応槽に、金属マグネシウム８０ｇ、エタノール１２１０ｇ及びヨウ素１ｇを投入し、攪拌しながら、還流条件下で系内から水素ガスの発生がなくなるまで反応させ、固体生成物を得た。この固体生成物を減圧乾燥させた後、ステンレス鋼製ボールミルに入れて１０時間粉砕した。
窒素で置換した内容積５リットルの攪拌機付きの三つ口フラスコに、上記粉砕した固体生成物１５０ｇ及び脱水処理したヘキサン３５００ミリリットルを加え、攪拌下で四塩化ケイ素３８ミリリットル及びエタノール３８ミリリットルを加えて７０℃で２時間反応を行なった。次に、四塩化チタンを２００ミリリットル加えて、７０℃で６時間攪拌した後、ヘキサンを用いて洗浄し、固体触媒成分を得た。
（高密度ポリエチレンの製造）
内容積２００リットルの攪拌機付き重合装置に、エチレン６ｋｇ／ｈｒ、ヘキサン１6.７リットル／ｈｒ、水素５５リットル／ｈｒの割合で連続的に供給するとともに、上記固体触媒成分をチタン原子換算で0.９ミリモル／ｈｒ及びトリイソブチルアルミニウムを２０ミリモル／ｈｒの速度で導入し、重合温度８０℃、重合圧力0.４ＭＰａ・Ｇ、滞留時間2.４時間の条件で重合を行なった。得られた高密度ポリエチレン（ＨＤＰＥ）をメタノール処理することにより、ＨＤＰＥの塩素濃度を５０ｐｐｍに調整した。
【００１９】
上記で得られたＰＰ及びＨＤＰＥを、環状リン酸エステル化合物としてアデカスタブ ＮＡ−１１（旭電化社製，一般式（１）においてＲ¹ がメチレン基、Ｒ² 及びＲ³ がｔ−ブチル基、Ｍ¹ がナトリウムのもの）又はアデカスタブ ＮＡ−２１（旭電化社製，一般式（３）においてＲ¹ がメチレン基、Ｒ² 及びＲ³ がｔ−ブチル基、Ｍ¹ がアルミニウムのもの）を、金属石鹸としてステアリン酸カルシウム（分子量：６０７）を用いた。上記ポリプロピレン又はポリエチレン１００重量部に、アデカスタブ ＮＡ−１１又はアデカスタブ ＮＡ−２１及びステアリン酸カルシウムを表１〜表５（ｐｐｍは重量ｐｐｍを示す。）に示す割合で加え、更に酸化防止剤として、イルガノックス１０１０（チバ・スペシャルティ・ケミカルズ社製）を0.１重量部及びイルガフォス１６８（チバ・スペシャルティ・ケミカルズ社製）を0.１重量部加え、十分に混合した後、４０ｍｍ単軸押出機にて溶融混練及び造粒してペレットを作製した。このペレットを用いて下記の方法により、腐食性、結晶化温度及び曲げ弾性率を測定した。また、ポリプロピレン及びポリエチレン中の塩素濃度を下記の方法により測定した。
【００２０】
（１）塩素濃度測定
ポリマー約１０ｇを１９０〜２３０℃においてプレスし、円盤状のシートを作製した後、理学電気社製の全蛍光Ｘ線分析装置システム３２７０を用いて測定した。
（２）腐食試験
十分に磨いた軟鋼板に厚さ５ｍｍのスペーサーを介してペレットを載せ、実際の成形温度に近い温度（約２５０℃）に加熱したプレス成形機を用い、0.１〜0.３ＭＰａの圧力で一定時間保持した。その後、冷却プレスし、軟鋼板から樹脂を剥ぎ取り、軟鋼板を、２５℃、相対湿度１００％に保った容器中に１週間放置した。軟鋼板表面の発錆状態を標準板（発錆度０〜４）と比較し、評価した。発錆度０は錆無し、発錆度４は全面に顕著に錆が発生した状態を示す。
（３）結晶化温度
ペレット約１０ｇをアルミニウム製パンに入れてクリンプし、パーキンエルマー社製のＤＳＣ７を用いて測定した。４０℃から２２０℃まで、１０℃／分で昇温し、２２０℃で３分間保持した後、４０℃まで１０℃／分で降温し、４０℃で３分間保持した。さらに、１０℃／分で２２０℃まで昇温し、降温時の発熱ピークのピークトップを結晶化温度した。
（４）曲げ弾性率
上記ペレットを用い、下記の条件で射出成形して試験片を製造し、ＪＩＳ Ｋ７２０３に準拠して曲げ弾性率を測定した。
成形機 東芝機械製，ＩＳＯ１００ＦIII
成形条件 温度：２２０℃，射出時間：１０秒，保圧時間：３秒，冷却時間：
２０秒，金型温度：４５℃
【００２１】
【表１】

【００２２】
【表２】

【００２３】
【表３】

【００２４】
【表４】

【００２５】
【表５】

【００２６】
【発明の効果】
本発明のポリオレフィン系樹脂組成物は、物性と耐腐食性とのバランスに優れるものである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polyolefin resin composition that is low in cost and exhibits excellent rigidity, hardness, and transparency due to the nucleating action of a cyclic phosphate compound.
[0002]
[Prior art]
In recent years, highly active catalysts have been developed as catalysts used in the production of polyolefin resins, and thus no deashing or washing steps are required in the production process. Along with this, chlorine, which is a catalyst residue, remains in the polyolefin resin. This residual chlorine is a factor that corrodes the molding die, and in order to prevent such corrosion, a prescription is made to add a metal soap such as calcium stearate to the polyolefin resin.
In order to improve the rigidity and transparency of the polyolefin resin, it is effective to add a nucleating agent such as a cyclic phosphate ester compound. When a metal soap and a cyclic phosphate ester compound are mixed, corrosion resistance is improved. It is expected that a polyolefin resin having excellent properties, rigidity and transparency will be obtained.
However, in a system where metal soap and cyclic phosphate compound are mixed, if metal soap remains in a large amount even after the chlorine in the polyolefin resin is neutralized, it reacts with metal soap and cyclic phosphate compound. This reaction changes the structure of the cyclic phosphate compound. This change reduces the effect obtained by adding the cyclic phosphate compound.
If the amount of metal soap added is reduced to prevent such a reaction, and the amount of metal soap added is insufficient to neutralize the chlorine in the polyolefin resin, the cyclic phosphate compound is added to the polyolefin. Since it reacts with chlorine in the resin, there is a problem that it cannot be avoided that the effect due to the addition of the cyclic phosphate compound is reduced.
[0003]
[Problems to be solved by the invention]
This invention is made | formed in view of the said situation, and aims at providing the polyolefin resin composition excellent in the balance of a physical property and corrosion resistance.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above object, the inventors of the present invention have obtained a cyclic reaction in a polyolefin resin composition comprising a polyolefin resin, a metal soap and a cyclic phosphate ester compound produced using a Ziegler catalyst. The content of the phosphate ester compound is in a certain range, and the molar concentration of the metal soap is in a certain range with respect to the molar concentration of residual chlorine contained in the polyolefin resin and the molar concentration of the cyclic phosphate compound. Furthermore, it has been found that a polyolefin-based resin composition having an excellent balance between physical properties and corrosion resistance can be obtained by defining the blending amounts of the cyclic phosphate compound and the metal soap. The present invention has been completed based on such findings.
That is, the present invention relates to (A) a polyolefin resin produced using a Ziegler catalyst, (B) a general formula (1), (2) or (3).
[0005]
[Chemical 2]

[0006]
(In the formula, R ¹ represents a direct bond, a sulfur atom, an alkylene group having 1 to 9 carbon atoms or an alkylidene group, and R ² , R ³ , R ⁴ and R ⁵ are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. M ¹ represents a 1-3 valent metal atom, and n is the valence of M ¹ .
A cyclic phosphate ester compound represented by formula (4) and (C)
(RCOO) _m M ² (4)
(In the formula, R represents an unsaturated or saturated hydrocarbon residue having 8 to 23 carbon atoms and 3 or less carbon-carbon unsaturated bonds, and M ² represents ² , 3, 12 or ² in the periodic table) Represents a group 13 metal element, and m is the valence of M ^2. )
A polyolefin resin composition comprising a metal soap represented by formula (A) , wherein the polyolefin resin of component (A) is a single type of polyethylene or polypropylene, and is detected by fluorescent X-ray method (A) component The residual chlorine concentration in the composition is X (weight ppm), the concentration of component (B) in the composition is Y (weight ppm), the concentration of component (C) is Z (weight ppm), and the molecular weight of component (C) is When B, the following formula (X × B) / 71 ≦ Z <2Y
And the content of the component (B) is 200 to 2000 ppm by weight in the polyolefin resin composition.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
As the polyolefin resin of the component (A) used in the present invention, one produced using a Ziegler catalyst is used. The Ziegler catalyst is, for example, a catalyst in which a transition metal halide and an alkylated product such as aluminum, alkaline earth metal, or alkali metal are combined. As the polyolefin resin of the component (A), a known method using such a catalyst is used. The manufactured product can be used. As the polyolefin resin is polyethylene or polypropylene. These are used alone.
The residual chlorine concentration in the polyolefin resin is measured by a fluorescent X-ray method. A normal fluorescent X-ray analyzer can be used for the measurement.
The cyclic phosphate compound of the component (B) used in the present invention is represented by the general formula (1), (2) or (3).
[0008]
[Chemical 3]

[0009]
(In the formula, R ¹ represents a direct bond, a sulfur atom, an alkylene group having 1 to 9 carbon atoms or an alkylidene group, and R ² , R ³ , R ⁴ and R ⁵ are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. , M ¹ represents a 1-3 valent metal atom, and n is the valence of M ¹ .
)
It is represented by R ¹ is preferably a methylene group, R ² , R ³ , R ⁴ and R ⁵ are preferably t-butyl groups, and M ¹ is preferably sodium, lithium, potassium, magnesium and aluminum.
Examples of the cyclic phosphate compound represented by the general formula (1) include sodium-2,2′-methylenebis (4,6-di-t-butylphenyl) phosphate, sodium-2,2′-ethylidenebis ( 4,6-di-t-butylphenyl) phosphate, lithium-2,2′-methylenebis (4,6-di-t-butylphenyl) phosphate, lithium-2,2′-ethylidenebis (4,6 -Di-t-butylphenyl) phosphate, sodium-2,2'-ethylidenebis (4-i-propyl-6-t-butylphenyl) phosphate, lithium-2,2'-methylenebis (4-methyl- 6-t-butylphenyl) phosphate, lithium-2,2′-methylenebis (4-ethyl-6-t-butylphenyl) phosphate, calcium bis [ 2,2′-thiobis (4-methyl-6-tert-butylphenyl) phosphate], calcium bis [2,2′-thiobis (4-ethyl-6-tert-butylphenyl) phosphate], calcium bis [ 2,2′-thiobis (4,6-di-t-butylphenyl) phosphate], magnesium bis [2,2′-thiobis (4,6-di-t-butylphenyl) phosphate], magnesium bis [ 2,2′-thiobis (4-t-octylphenyl) phosphate], sodium-2,2′-butylidenebis (4,6-dimethylphenyl) phosphate, sodium-2,2′-butylidenebis (4,6- Di-t-butylphenyl) phosphate, sodium-2,2′-t-octylmethylenebis (4,6-dimethylphenyl) phosphate, Thorium-2,2′-t-octylmethylene bis (4,6-di-t-butylphenyl) phosphate, calcium bis [2,2′-methylenebis (4,6-di-t-butylphenyl) phosphate ], Magnesium bis [2,2'-methylenebis (4,6-di-t-butylphenyl) phosphate], barium bis [2,2'-methylenebis (4,6-di-t-butylphenyl) phosphate] ] Sodium-2,2'-methylenebis (4-methyl-6-t-butylphenyl) phosphate, sodium-2,2'-methylenebis (4-ethyl-6-t-butylphenyl) phosphate, sodium ( 4,4′-dimethyl-6,6′-di-t-butyl-2,2′-biphenyl) phosphate, calcium bis [(4,4′-dimethyl-6, '-Di-t-butyl-2,2'-biphenyl) phosphate], sodium-2,2'-ethylidenebis (4-s-butyl-6-t-butylphenyl) phosphate, sodium-2,2 '-Methylenebis (4,6-dimethylphenyl) phosphate, sodium-2,2'-methylenebis (4,6-diethylphenyl) phosphate, potassium-2,2'-ethylidenebis (4,6-di-t -Butylphenyl) phosphate, calcium bis [2,2'-ethylidenebis (4,6-di-t-butylphenyl) phosphate], magnesium bis [2,2'-ethylidenebis (4,6-di-) t-butylphenyl) phosphate], barium bis [2,2′-ethylidenebis (4,6-di-t-butylphenyl) phosphate], aluminum Umtris [2,2′-methylenebis (4,6-di-t-butylphenyl) phosphate], aluminum tris [2,2′-ethylidenebis (4,6-di-t-butylphenyl) phosphate] and What is shown by a following formula is mentioned.
[0010]
[Formula 4]

[0011]
Examples of the cyclic phosphate compound represented by the general formula (2) include those represented by the following formula.
[0012]
[Chemical formula 5]

[0013]
Examples of the cyclic phosphate compound represented by the general formula (3) include those represented by the following formula. A cyclic phosphate ester compound may be used individually by 1 type, and may be used in combination of 2 or more type.
[0014]
[Chemical 6]

[0015]
In the polyolefin-based resin composition of the present invention, the content of the cyclic phosphate compound is 100 to 5000 ppm, preferably 200 to 2000 ppm. If the cyclic phosphate compound is less than 100 ppm, a sufficient nucleating effect cannot be obtained, and even if it exceeds 5000 ppm, an effect commensurate with the amount of addition cannot be obtained, resulting in high costs. .
The metal soap of the component (C) used in the present invention has the general formula (4)
(RCOO) _m M ² (4)
(In the formula, R represents an unsaturated or saturated hydrocarbon residue having 8 to 23 carbon atoms and 3 or less carbon-carbon unsaturated bonds, and M ² represents ² , 3, 12 or ² in the periodic table) Represents a group 13 metal element, and m is the valence of M ^2. )
It is represented by In the general formula (4), if the carbon number of R is less than 8, the compatibility with the polyolefin resin is poor and the surface of the polyolefin product becomes sticky due to the leaching. When the carbon number of R exceeds 23, the effect decreases rapidly with an increase in the carbon number. On the other hand, if the number of carbon-carbon unsaturated bonds exceeds 3, the effect of preventing thermal degradation is reduced. When M ² is a metal element belonging to Groups 1 and 11 of the periodic table, the water solubility of the metal soap is increased, which is not preferable. When M ² is a metal element of Group 4 to 10 or Group 14 or more of the periodic table, such as iron, cobalt or nickel, the deterioration of the polyolefin resin is promoted when the metal soap is blended with the polyolefin resin, It is unsuitable because it lowers its mechanical strength and causes discoloration due to deterioration. In one metal soap, m fatty acid portions may be the same or different.
Preferred fatty acids include lauric acid (n-C ₁₁ H ₂₃ ; R represents the same hereinafter), myristic acid (n-C ₁₃ H ₂₇ ), palmitic acid (n-C ₁₅ H ₃₁ ), stearic acid (n- C ₁₇ H _35), oleic acid _{(n-C 17 H 32)} , linoleic acid _{(n-C 17 H 30)} , include linoleic acid _{(n-C 17 H 28)} . Examples of M ² include beryllium, magnesium, calcium, zinc, and aluminum. In the present invention, calcium is preferable. A metal soap may be used individually by 1 type, and may be used in combination of 2 or more type.
[0016]
In the present invention, the metal soap of component (C) has a residual chlorine concentration in component (A) detected by the fluorescent X-ray method of X (weight ppm), and the concentration of component (B) in the composition is Y. (Weight ppm), when the concentration of component (C) is Z (weight ppm) and the molecular weight of component (C) is B, the following formula (X × B) / 71 ≦ Z <2Y
The amount which satisfies is blended. When Z is less than (X × B) / 71, residual chlorine in the polyolefin resin and the cyclic phosphate ester compound of component (B) react. On the other hand, when Z is 2Y or more, the metal soap and the cyclic phosphate ester compound react with each other, and the effect of adding the cyclic phosphate decreases.
In addition to the essential components described above, various additives such as antioxidants, inorganic fillers, ultraviolet absorbers, weathering agents and the like may be added to the polyolefin resin composition of the present invention as necessary. Moreover, the polyolefin resin composition of this invention can be manufactured by mixing the said essential component and another additive component by a well-known method.
The polyolefin resin composition of the present invention can be used for molding various injection molded products and sheets.
[0017]
【Example】
EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
Examples 1-6, Comparative Examples 1-10
(1) Production of polypropylene (preparation of solid catalyst component)
600 ml of dehydrated heptane and 160 g of diethoxymagnesium were added to a three-necked flask equipped with a stirrer with an internal volume of 5 liters substituted with nitrogen. After heating to 40 ° C. and adding 24 ml of silicon tetrachloride and stirring for 20 minutes, 23 ml of diethyl phthalate was added. This solution was heated to 80 ° C., and subsequently 770 ml of titanium tetrachloride was added dropwise, followed by stirring at an internal temperature of 110 ° C. for 2 hours. Then, stirring was stopped, solid was settled, and the supernatant liquid was extracted. Washing was performed 7 times using 90 ° C. dehydrated heptane. Next, 1220 ml of titanium tetrachloride was added, and the mixture was stirred at an internal temperature of 110 ° C. for 2 hours. Then, stirring was stopped, solid was settled, and the supernatant liquid was extracted. Washing with dehydrated heptane at 60 ° C. was repeated 7 times to obtain a solid catalyst component.
(Preparation of prepolymerization catalyst)
48 g of the above solid catalyst component and 400 ml of dehydrated heptane were added to a three-neck flask equipped with a stirrer with an internal volume of 1 liter substituted with nitrogen. The temperature was raised to 40 ° C., and 2.0 ml of triethylaluminum and 6.3 ml of dicyclopentyldimethoxysilane were added. Thereafter, propylene gas was circulated and reacted for 2 hours. Thereafter, it was thoroughly washed with dehydrated heptane to obtain a prepolymerized catalyst.
(Manufacture of polypropylene)
Add 1800 ml of dehydrated heptane, 10 mmol of triethylaluminum, and 1.25 mmol of dicyclopentyldimethoxysilane to a 5 liter stainless steel autoclave with a charging tube that has been thoroughly dried, and raise the temperature to 80 ° C. Hydrogen was introduced so that the pressure became 0.2 MPa · G, and then propylene was introduced to make the total pressure 0.8 MPa · G. A prepolymerized catalyst of 100 milliliters of dehydrated heptane and 0.1 millimole in terms of titanium was placed in the charging tube and introduced into the autoclave by pressure balance. Polymerization was carried out for 1 hour while introducing propylene so that the total pressure was 0.8 MPa · G. Thereafter, the temperature was lowered, the pressure was released, the contents were filtered, and vacuum-dried to obtain non-deashed polypropylene (PP). When the chlorine concentration in PP was measured by the method described later, it was 80 ppm.
(Adjustment of chlorine concentration)
After propylene was polymerized for 1 hour in the same manner as described above, the temperature was lowered and the pressure was released, and the contents were put into methanol, filtered, and vacuum dried to obtain PP with adjusted chlorine concentration.
[0018]
(2) Production of high density polyethylene (Preparation of solid catalyst component)
Into a reaction vessel equipped with a stirrer having an internal volume of 5 liters substituted with nitrogen, 80 g of magnesium metal, 1210 g of ethanol and 1 g of iodine were added and reacted while stirring until the generation of hydrogen gas disappeared from the system under reflux conditions. The product was obtained. The solid product was dried under reduced pressure and then placed in a stainless steel ball mill and pulverized for 10 hours.
To a three-necked flask equipped with a stirrer with an internal volume of 5 liters substituted with nitrogen, 150 g of the pulverized solid product and 3500 ml of dehydrated hexane were added, and 38 ml of silicon tetrachloride and 38 ml of ethanol were added under stirring. Reaction was performed at 70 degreeC for 2 hours. Next, 200 ml of titanium tetrachloride was added and stirred at 70 ° C. for 6 hours, followed by washing with hexane to obtain a solid catalyst component.
(Manufacture of high density polyethylene)
While continuously supplying ethylene 6 kg / hr, hexane 16.7 liters / hr, and hydrogen 55 liters / hr to a polymerization apparatus equipped with a stirrer having an internal volume of 200 liters, the solid catalyst component was added in an amount of 0.001 in terms of titanium atoms. 9 mmol / hr and triisobutylaluminum were introduced at a rate of 20 mmol / hr, and polymerization was carried out under conditions of a polymerization temperature of 80 ° C., a polymerization pressure of 0.4 MPa · G, and a residence time of 2.4 hours. The resulting high-density polyethylene (HDPE) was treated with methanol to adjust the HDPE chlorine concentration to 50 ppm.
[0019]
PP and HDPE obtained above were used as cyclic phosphate ester compounds as ADK STAB NA-11 (manufactured by Asahi Denka Co., Ltd., in general formula (1), R ¹ is a methylene group, R ² and R ³ are t-butyl groups, M ¹ is sodium, or Adekastab NA-21 (Asahi Denka Co., Ltd., R ¹ is a methylene group, R ² and R ³ are t-butyl groups, M ¹ is aluminum) Calcium stearate (molecular weight: 607) was used as soap. Irganox is added to 100 parts by weight of the above-mentioned polypropylene or polyethylene in a proportion shown in Tables 1 to 5 (ppm indicates weight ppm), and further as an antioxidant, Adekastab NA-11 or Adekastab NA-21 and calcium stearate. Add 0.1 part by weight of 1010 (Ciba Specialty Chemicals) and 0.1 part by weight of Irgafos 168 (Ciba Specialty Chemicals), mix thoroughly, and melt in a 40 mm single screw extruder. Pellets were prepared by kneading and granulating. Corrosivity, crystallization temperature and flexural modulus were measured using the pellets by the following method. Moreover, the chlorine concentration in polypropylene and polyethylene was measured by the following method.
[0020]
(1) Chlorine concentration measurement About 10 g of a polymer was pressed at 190 to 230 ° C. to prepare a disk-shaped sheet, and then measured using a total fluorescent X-ray analyzer system 3270 manufactured by Rigaku Corporation.
(2) Corrosion test Using a press molding machine with pellets placed on a sufficiently polished mild steel plate with a spacer of 5 mm thickness and heated to a temperature close to the actual molding temperature (about 250 ° C.), 0.1 to 0 The pressure was maintained at a pressure of 3 MPa for a certain time. Then, it was cooled and pressed, the resin was peeled off from the mild steel plate, and the mild steel plate was left in a container kept at 25 ° C. and relative humidity 100% for one week. The rusting state on the surface of the mild steel plate was compared with a standard plate (rusting degree 0 to 4) and evaluated. A degree of rusting of 0 indicates no rusting, and a degree of rusting of 4 indicates a state in which rust is significantly generated on the entire surface.
(3) About 10 g of crystallization temperature pellets were put in an aluminum pan, crimped, and measured using DSC7 manufactured by PerkinElmer. The temperature was raised from 40 ° C. to 220 ° C. at 10 ° C./min, held at 220 ° C. for 3 minutes, then lowered to 40 ° C. at 10 ° C./min, and held at 40 ° C. for 3 minutes. Furthermore, the temperature was raised to 220 ° C. at 10 ° C./min, and the peak top of the exothermic peak when the temperature was lowered was set to the crystallization temperature.
(4) Flexural modulus Using the above pellets, a test piece was manufactured by injection molding under the following conditions, and the flexural modulus was measured according to JIS K7203.
Molding machine, Toshiba Machine, ISO100FIII
Molding conditions Temperature: 220 ° C., injection time: 10 seconds, pressure holding time: 3 seconds, cooling time:
20 seconds, mold temperature: 45 ℃
[0021]
[Table 1]

[0022]
[Table 2]

[0023]
[Table 3]

[0024]
[Table 4]

[0025]
[Table 5]

[0026]
【The invention's effect】
The polyolefin resin composition of the present invention has an excellent balance between physical properties and corrosion resistance.

Claims (3)

(A) Polyolefin resin produced using a Ziegler catalyst, (B) General formula (1), (2) or (3)

(In the formula, R ¹ represents a direct bond, a sulfur atom, an alkylene group having 1 to 9 carbon atoms or an alkylidene group, and R ² , R ³ , R ⁴ and R ⁵ are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. M ¹ represents a 1-3 valent metal atom, and n is the valence of M ¹ .
A cyclic phosphate ester compound represented by formula (4) and (C)
(RCOO) _m M ² (4)
(In the formula, R represents an unsaturated or saturated hydrocarbon residue having 8 to 23 carbon atoms and 3 or less carbon-carbon unsaturated bonds, and M ² represents ² , 3, 12 or ² in the periodic table) Represents a group 13 metal element, and m is the valence of M ^2. )
A polyolefin resin composition comprising a metal soap represented by formula (A) , wherein the polyolefin resin of component (A) is a single type of polyethylene or polypropylene, and is detected by fluorescent X-ray method (A) component The residual chlorine concentration in the composition is X (weight ppm), the concentration of component (B) in the composition is Y (weight ppm), the concentration of component (C) is Z (weight ppm), and the molecular weight of component (C) is When B, the following formula (X × B) / 71 ≦ Z <2Y
And the content of component (B) is 200 to 2000 ppm by weight in the polyolefin resin composition. The polyolefin resin composition according to claim 1, wherein the component (B) is a cyclic phosphate compound represented by the general formula (1). The polyolefin resin composition according to claim 1, wherein the component (B) is a cyclic phosphate ester compound represented by the general formula (3).