JP3729372B2 - Polymer composition - Google Patents

Description

【００２１】
（ここで、Ｒ₁，Ｒ₂，Ｒ₃，およびＲ₄はそれぞれ、水素、ハロゲン、炭素数１〜７までの第一級または第二級低級アルキル基、フェニル基、ハロアルキル基、アミノアルキル基、炭化水素オキシ基または少なくとも２個の炭素原子がハロゲン原子と酸素原子とを隔てているハロ炭化水素オキシ基からなる群から選択されるものであり、互いに同一でも異なっていてもよい）からなり、還元粘度（０．５ｇ／ｄｌ，クロロホルム溶液，３０℃測定）が、０．１５〜０．７０の範囲、より好ましくは０．２０〜０．６０の範囲にあるホモ重合体および／または共重合体である。
【００２２】
このＰＰＥの具体的な例としては、例えばポリ（２，６−ジメチル−１，４−フェニレンエーテル）、ポリ（２−メチル−６−エチル−１，４−フェニレンエーテル）、ポリ（２−メチル−６−フェニル−１，４−フェニレンエーテル）、ポリ（２，６−ジクロロ−１，４−フェニレンエーテル）等が挙げられ、さらに２，６−ジメチルフェノールと他のフェノール類（例えば、２，３，６−トリメチルフェノールや２−メチル−６−ブチルフェノール）との共重合体のごときポリフェニレンエーテル共重合体も挙げられる。中でもポリ（２，６−ジメチル−１，４−フェニレンエーテル）、２，６−ジメチルフェノールと２，３，６−トリメチルフェノールとの共重合体が好ましく、さらにポリ（２，６−ジメチル−１，４−フェニレンエーテル）が好ましい。
【００２３】
かかるＰＰＥの製造方法は公知の方法で得られるものであれば特に限定されるものではなく、例えば、米国特許第３３０６８７４号記載のＨａｙによる第一銅塩とアミンのコンプレックスを触媒として用い、例えば２，６−キシレノールを酸化重合することにより容易に製造でき、そのほかにも米国特許第３３０６８７５号、同第３２５７３５７号および同第３２５７３５８号、特公昭５２−１７８８０号および特開昭５０−５１１９７号および同６３−１５２６２８号等に記載された方法で容易に製造できる。
【００２４】
また、本発明で用いるＰＰＥは、上記したＰＰＥのほかに、該ＰＰＥとスチレン系モノマーおよび／もしくはα，β−不飽和カルボン酸またはその誘導体とをラジカル発生剤の存在下、非存在下で溶融状態、溶液状態、スラリー状態で８０〜３５０℃の温度下で反応させることによって得られる公知の変性（該スチレン系モノマーおよび／もしくはα，β−不飽和カルボン酸またはその誘導体が０．０１〜１０重量％グラフトまたは付加）ＰＰＥであってもよく、さらに上記したＰＰＥと該変性ＰＰＥの任意の割合の混合物であってもかまわない。
【００２５】
また、本発明で用いるＰＰＥは上記したＰＰＥのほかに、これらＰＰＥ１００重量部に対してポリスチレンまたはハイインパクトポリスチレンを４００重量部を超えない範囲で加えたものも好適に用いることができる。
【００２６】
つぎに本発明で（ｃ）成分として用いる水添ブロック共重合体は、（ａ）成分のポリプロピレン樹脂と（ｂ）成分のポリフェニレンエーテル樹脂を溶融混合した際に、（ｂ）成分のポリフェニレンエーテル樹脂を（ａ）成分のポリプロピレン樹脂中に好適に微分散させたり、（ａ）成分のポリプロピレン樹脂を（ｂ）成分のポリフェニレンエーテル樹脂中に好適に微分散させる能力を有する水添ブロック共重合体である。すなわち、本発明では、ブロック共重合体が、ビニル芳香族化合物を主体とする少なくとも１個の重合体ブロックＡと、共役ジエン化合物の１，２−ビニル結合量および３，４−ビニル結合量の合計量が５〜４５％未満である少なくとも１個の共役ジエン化合物を主体とする重合体ブロックＤと、イソプレンの１，２−ビニル結合量および３，４−ビニル結合量の合計量が４５〜７０％である少なくとも１個のイソプレンを主体とする重合体ブロックＩより構成され、かつＤ／Ｉ＝５／９５〜６０／４０（重量比）であるブロック共重合体を水素添加してなる水添ブロック共重合体である。
【００２７】
このような構造を示す水添ブロック共重合体としては、例えば、Ａ−Ｄ−Ｉ、Ａ−Ｄ−Ｉ−Ａ、Ａ−Ｉ−Ａ−Ｄ、Ａ−Ｉ−Ａ−Ｉ−Ｄ、Ａ−Ｄ−Ａ−Ｉ−Ａ−Ｉ、Ｄ−Ａ−Ｉ、Ｄ−Ａ−Ｄ−Ｉ、Ｄ−Ａ−Ｄ−Ａ−Ｉ、Ｄ−Ａ−Ｄ−Ａ−Ｄ−Ｉ等が挙げられる。
【００２８】
ここで、水添する前の共役ジエン化合物を主体とする重合体ブロックＤの１，２−ビニル結合量もしくは３，４−ビニル結合量の合計量（以下、ビニル結合量と略記する）は、５〜４５％未満、好ましくは１０〜４５％未満、より好ましくは３０〜４５％未満である。かかる重合体ブロックＤのビニル結合量が４５％以上であるとポリプロピレン樹脂とポリフェニレンエーテル樹脂の混和性は向上するが、得られるポリマー組成物の低温衝撃強度は顕著に低下し好ましくない。
【００２９】
また、水添する前のイソプレンを主体とする重合体ブロックＩの１，２−ビニル結合量もしくは３，４−ビニル結合量の合計量（以下、ビニル結合量と略記する）は、４５〜７０％、好ましくは４５〜６０％、より好ましくは４８〜５８％である。かかる重合体ブロックＩのビニル結合量が４５％未満であるとポリプロピレン樹脂とポリフェニレンエーテル樹脂の混和性が低下し、得られるポリマー組成物が層剥離をおこしたり、制振性能が極度に悪化し好ましくない。またビニル結合量が７０％を超えてもポリプロピレン樹脂とポリフェニレンエーテル樹脂の混和性は大幅に改良されるものではなく、また制振性能も顕著に改良されるものではない。
【００３０】
これらの１，２−ビニル結合量もしくは３，４−ビニル結合量は通常、赤外分光光度計やＮＭＲ等で知ることができる。
【００３１】
また、（Ｃ）成分の水添ブロック共重合体において、重合体ブロックＤと重合体ブロックＩは、Ｄ／Ｉ＝５／９５〜６０／４０（重量比）を満たすことが必要である。Ｄが５％未満では低温衝撃強度の低下が著しく、また４０％を越えると低温衝撃強度は優れるものの制振性の低下が著しく好ましくない。
【００３２】
この（Ｃ）成分の水添ブロック共重合体は、その水素添加する前のブロック共重合体において結合したビニル芳香族化合物を１５〜９５重量％、好ましくは２０〜７０重量％、さらに好ましくは３５〜５０重量％含んでいる。
【００３３】
またブロック構造に言及すると、ビニル芳香族化合物を主体とする重合体ブロックＡが、ビニル芳香族化合物のホモ重合体ブロックまたは、ビニル芳香族化合物を５０重量％を超え好ましくは７０重量％以上含有するビニル芳香族化合物と共役ジエン化合物との共重合体ブロックの構造を有しており、そしてさらに、共役ジエン化合物を主体とする重合体ブロックＤが、共役ジエン化合物のホモ重合体ブロックまたは、共役ジエン化合物を５０重量％を超え好ましくは７０重量％以上含有する共役ジエン化合物とビニル芳香族化合物との共重合体ブロックの構造を有するものである。
【００３４】
そしてイソプレンを主体とする重合体ブロックＩが、イソプレンのホモ重合体ブロックまたは、イソプレンを５０重量％を超え好ましくは７０重量％以上含有するイソプレンとビニル芳香族化合物、イソプレン以外の共役ジエン化合物との共重合体ブロックの構造を有するものである。
【００３５】
また、これらのビニル芳香族化合物を主体とする重合体ブロックＡ、共役ジエン化合物を主体とする重合体ブロックＤおよびイソプレンを主体とする重合体ブロックＩは、それぞれの重合体ブロックにおける分子鎖中の共役ジエン化合物またはビニル芳香族化合物の分布がランダム、テーパード（分子鎖に沿ってモノマー成分が増加または減少するもの）、一部ブロック状またはこれらの任意の組み合わせで成っていてもよく、該ビニル芳香族化合物を主体とする重合体ブロックＡおよび該共役ジエン化合物を主体とする重合体ブロックＤおよびイソプレンを主体とする重合体ブロックＩはそれぞれ少なくとも１個以上であり、各重合体ブロックはそれぞれ同一構造であってもよく、異なる構造であってもよい。
【００３６】
このブロック共重合体を構成するビニル芳香族化合物としては、例えば、スチレン、α−メチルスチレン、ビニルトルエン、ｐ−ｔｅｒｔ−ブチルスチレン、ジフェニルエチレン等のうちから１種または２種以上が選択でき、中でもスチレンが好ましい。また、共役ジエン化合物としては、例えば、ブタジエン、イソプレン、１，３−ペンタジエン、２，３−ジメチル−１，３−ブタジエン等のうちから１種または２種以上が選ばれ、中でもブタジエン、イソプレンおよびこれらの組み合わせが好ましい。
【００３７】
また、上記の構造を有するブロック共重合体の数平均分子量は５，０００〜１，０００，０００、好ましくは１０，０００〜８００，０００、さらに好ましくは３０，０００〜５００，０００の範囲であり、分子量分布〔ゲルパーミエーションクロマトグラフィーで測定し、検量線として用いた単分散ポリスチレン分子量で換算した重量平均分子量（Ｍｗ）と数平均分子量（Ｍｎ）の比〕は１０以下である。さらに、このブロック共重合体の分子構造は、直鎖状、分岐状、放射状あるいはこれらの任意の組み合わせのいずれであってもよい。
【００３８】
このような構造を持つブロック共重合体は、上記したブロック共重合体の共役ジエン化合物を主体とする重合体ブロックＤおよびイソプレンを主体とする重合体ブロックＩの脂肪族系二重結合を水素添加した水添ブロック共重合体として本発明の（ｃ）成分として用いることができる。かかる脂肪族系二重結合の水素添加率は少なくとも６０％を超え、好ましくは８０％以上、より好ましくは耐熱安定性の観点より８５％以上である。そしてこの水素添加率は通常、赤外分光光度計やＮＭＲ等で知ることができる。
【００３９】
これらの上記した（ｃ）成分の水添ブロック共重合体は、上記した構造を有するものであればどのような製造方法で得られるものであってもかまわない。公知の製造方法の例としては、例えば、特開昭４７−１１４８６号公報、特開昭４９−６６７４３号公報、特開昭５０−７５６５１号公報、特開昭５４−１２６２５５号公報、特開昭５６−１０５４２号公報、特開昭５６−６２８４７号公報、特開昭５６−１００８４０号公報、特開平２−３００２１８号公報、英国特許第１１３０７７０号および米国特許第３２８１３８３号および同第３６３９５１７号に記載された方法や英国特許第１０２０７２０号および米国特許第３３３３０２４号および同第４５０１８５７号に記載された方法がある。
【００４０】
また、本発明で用いる（ｃ）成分の水添ブロック共重合体は、上記した水添ブロック共重合体のほかに、該水添ブロック共重合体とα，β−不飽和カルボン酸またはその誘導体とをラジカル発生剤の存在下、非存在下で溶融状態、溶液状態、スラリー状態で８０〜３５０℃の温度下で反応させることによって得られる公知の変性（該α，β−不飽和カルボン酸またはその誘導体が０．０１〜１０重量％グラフトまたは付加）水添ブロック共重合体であってもよく、さらに上記した水添ブロック共重合体と該変性水添ブロック共重合体の任意の割合の混合物であってもかまわない。
【００４１】
本発明のポリマー組成物は、上記した（ａ）〜（ｃ）成分を基本成分として構成される。（ａ）成分のポリプロピレン樹脂の配合量は、５〜９５重量％であり、好ましくは１０〜９０重量％である。かかる配合量が５重量％未満では、得られるポリマー組成物の耐熱性は優れるものの、成形加工性、耐溶剤性が劣り好ましくない。また、９５重量％を超える場合は成形加工性、耐溶剤性は良好なものの、耐熱性が劣り耐熱性材料として利用できない。
【００４２】
（ｂ）成分のポリフェニレンエーテルの配合量は９５〜５重量％、好ましくは９０〜１０重量％である。かかる配合量が９５重量％を超える場合、得られるポリマー組成物の耐熱性は極度に優れるものの、成形加工性、耐溶剤性が劣り好ましくない。また、５重量％未満では成形加工性、耐溶剤性に優れるものの、耐熱性が劣り耐熱材料として利用できない。
【００４３】
（ｃ）成分の水添ブロック共重合体の配合量は、上記（ａ）、（ｂ）成分の合計１００重量部に対して、１〜３０重量部である。かかる配合量が１重量部未満では混和剤としての効果、制振性および低温衝撃強度の改良効果が見られず好ましくない。また、かかる配合量が３０重量部を超えても、制振性および低温衝撃強度の改良効果は顕著でなく、逆に（ａ）、（ｂ）成分が示す作用効果の耐熱性、耐溶剤性、剛性および機械的強度に対して低下をもたらし好ましくない。
【００４４】
本発明では、上記の成分の他に、本発明の特徴および効果を損なわない範囲で必要に応じて他の附加的成分、例えば、結合スチレン量１０〜９０％のスチレン−ブタジエンブロック共重合体、結合スチレン量１０〜９０％のスチレン−イソプレンブロック共重合体およびこれらブロック共重合体の共役ジエン化合物に起因する脂肪族系二重結合の８０％以上を水素添加した本発明とは異なる構造の水添ブロック共重合体、酸化防止剤、金属不活性化剤、難燃剤（有機リン酸エステル系化合物、無機リン系化合物、芳香族ハロゲン系難燃剤、シリコーン系難燃剤など）、フッ素系ポリマー、可塑剤（オイル、低分子量ポリエチレン、エポキシ化大豆油、ポリエチレングリコール、脂肪酸エステル類等）、三酸化アンチモン等の難燃助剤、耐候（光）性改良剤、ポリオレフィン用造核剤、スリップ剤、無機または有機の充填材や強化材（ガラス繊維、カーボン繊維、ポリアクリロニトリル繊維、ウィスカー、マイカ、タルク、カーボンブラック、酸化チタン、炭酸カルシウム、チタン酸カリウム、ワラストナイト、導電性金属繊維、導電性カーボンブラック等）、各種着色剤、離型剤等を添加してもかまわない。
【００４５】
本発明のポリマー組成物は、上記した各成分を用いて、（ｂ）成分と（ｃ）成分を前もって溶融混練したものを再度（ａ）成分と一緒に溶融混練する方法、（ｃ）成分の一部を前もって（ａ）成分や（ｂ）成分と予備混練しこれらの予備混練物を再度一緒に溶融混練する方法、押出機の最初のフィード口より（ｂ）成分と（ｃ）成分を供給し、溶融状態のこれらの組成物中に押出機の中間口より（ａ）成分を供給し溶融混練する方法などの種々の方法で製造することができる。これらの方法として例えば、単軸押出機、二軸押出機、ロール、ニーダー、ブラベンダープラストグラフ、バンバリーミキサー等による加熱溶融混練方法が挙げられるが、中でも二軸押出機を用いた溶融混練方法が最も好ましい。この際の溶融混練温度は特に限定されるものではないが、通常２００〜３５０℃の中から任意に選ぶことができる。
【００４６】
このようにして得られる本発明のポリマー組成物は、従来より公知の種々の方法、例えば、射出成形、押出成形、中空成形により各種部品の成形体として成形できる。これら各種部品としては、例えば自動車部品が挙げられ、具体的には、バンパー、フェンダー、ドアーパネル、各種モール、エンブレム、エンジンフード、ホイールキャップ、ルーフ、スポイラー、各種エアロパーツ等の外装品や、インストゥルメントパネル、コンソールボックス、トリム等の内装部品等に適している。さらに、電気機器の内外装部品としても好適に使用でき、具体的には各種コンピューターおよびその周辺機器、その他のＯＡ機器、テレビ、ビデオ、各種ディスクプレーヤー等のキャビネット、シャーシー、トレーや冷蔵庫等の部品用途に適している。
【００４７】
【発明の実施の形態】
本発明を実施例によって、さらに詳細に説明するが、これらの実施例により限定されるものではない。
【００４８】
実施例に使用した（ａ）成分のポリプロピレン樹脂
（ａ）：ホモ−ポリプロピレン
融点＝１６０℃、ＭＦＩ＝１．６
実施例に使用した（ｂ）成分のＰＰＥ
（ｂ）：２，６−キシレノールを酸化重合して得た、還元粘度０．４５のポリフェニレンエーテル
実施例に使用した（ｃ）成分の水添ブロック共重合体
（ｃ−１）：ポリスチレン−水素添加されたビニル結合量３６％のポリブタジエン−水素添加されたビニル結合量５５％のポリイソプレンの構造を有し、結合スチレン量３５％、水素添加されたビニル結合量３６％のポリブタジエン／水素添加されたビニル結合量５５％のポリイソプレン＝３０／７０（重量比）、ポリスチレンの数平均分子量２８０００、ポリブタジエン部とポリイソプレン部の全水素添加率が８９．５％の水添ブロック共重合体を合成し、このポリマーを（ｃ−１）とした。
【００４９】
（ｃ−２）：同様に、ポリスチレン−水素添加されたビニル結合量１１％のポリイソプレン−水素添加されたビニル結合量５３％のポリイソプレン−ポリスチレンの構造を有し、結合スチレン量４８％、水素添加されたビニル結合量１１％のポリイソプレン／水素添加されたビニル結合量５３％のポリイソプレン＝５０／５０（重量比）、２つのポリスチレンブロックの数平均分子量が同一で２８３００、全ポリイソプレン部の水素添加率が９２．５％の水添ブロック共重合体を合成し、このポリマーを（ｃ−２）とした。
【００５０】
（ｃ−３）：同様に、水素添加されたビニル結合量４０％のポリブタジエン−ポリスチレン−水素添加されたビニル結合量５８％のポリイソプレン−ポリスチレンの構造を有し、結合スチレン量２０％、水素添加されたビニル結合量４０％のポリブタジエン／水素添加されたビニル結合量５８％のポリイソプレン＝８／９２（重量比）、２つのポリスチレンブロックの数平均分子量が同一で１００００、ポリブタジエン部とポリイソプレン部の全水素添加率が８７．１％の水添ブロック共重合体を合成し、このポリマーを（ｃ−３）とした。
【００５１】
（ｃ−４）：さらに、ポリスチレン−水素添加されたビニル結合量５５％のポリイソプレンの構造を有し、結合スチレン量３６％、ポリスチレンの数平均分子量３００００、ポリイソプレン部の全水素添加率が８５．４％の水添ブロック共重合体を合成し、このポリマーを（ｃ−４）とした。
【００５２】
（ｃ−５）：同様に、ポリスチレン−水素添加されたビニル結合量５６％のポリイソプレン−ポリスチレンの構造を有し、結合スチレン量２１％、２つのポリスチレンブロックの数平均分子量が同一で８９００、ポリイソプレン部の全水素添加率が８４．４％の水添ブロック共重合体を合成し、このポリマーを（ｃ−５）とした。
【００５３】
なお、得られたポリマー組成物の各特性は下記に示す方法で求めた。
【００５４】
（１）耐熱性試験
ＡＳＴＭ Ｄ６４８に準拠し、荷重１８．６Ｋｇにて熱変形温度（ＨＤＴ）を測定した。
【００５５】
（２）低温衝撃試験
ＡＳＴＭ Ｄ２５６に準拠し、厚さ１／８インチの射出成形片にて−３０℃のノッチ付きアイゾット衝撃強度を測定した。
【００５６】
（３）制振性（損失係数η）
２チャンネル高速フーリエ変換装置を用いて、非接触ランダム加振による片持ち梁法により測定温度２３℃において測定した。
【００５７】
実施例１〜７および比較例１〜６
ポリプロピレン樹脂、ポリフェニレンエーテル樹脂および水添ブロック共重合体を表１に示した組成で配合し、２６０〜２８０℃に設定したベントポート付き二軸押出機（ＺＳＫ−２５；ＷＥＲＮＥＲ＆ＰＦＬＥＩＤＥＲＥＲ社製、ドイツ国）を用いて溶融混練しペレットとして得た。
【００５８】
このペレットを用いて２４０〜２８０℃に設定したスクリューインライン型射出成形機に供給し、金型温度６０℃の条件でアイゾット衝撃試験用テストピースおよび熱変形温度測定用テストピースを射出成形した。また、さらに制振性能測定用テストピースとして厚さ１／８インチ、幅０．５インチ、長さ５インチの射出成形した。これらのテストピースを前記した方法で熱変形温度（ＨＤＴ）、低温アイゾット衝撃強度、制振性能を測定した。これらの結果を併せて表１に載せた。
【００５９】
【表１】

【００６０】
これらの結果より、水添ブロック共重合体として、構成される共役ジエン化合物を主体とする重合体ブロックにおいて、１，２−ビニル結合量および３，４−ビニル結合量の合計量が５〜４５％未満である少なくとも１個の共役ジエン化合物を主体とする重合体ブロックＤと、イソプレンの１，２−ビニル結合量および３，４−ビニル結合量の合計量が４５〜７０％である少なくとも１個のイソプレンを主体とする重合体ブロックＩを併せ持つ水添ブロック共重合体を用いることにより、制振性と低温衝撃強および熱変形温度のバランスに優れたポリマー組成物が得られる。また、本発明外の水添ブロック共重合体として共役ジエン化合物を主体とする重合体ブロックが、単にイソプレンの１，２−ビニル結合量および３，４−ビニル結合量の合計量が４５〜７０％である少なくとも１個のイソプレンを主体とする重合体ブロックＩだけで構成される水添ブロック共重合体を用いた場合、制振性能は優れるが低温衝撃強度が極度に悪化する。また、低温衝撃強度を高めるためにこの本発明外の水添ブロック共重合体を多く配合しても、制振性能および低温衝撃強度の顕著な改良は望めず、逆に耐熱性（熱変形温度）が大きく低下し物性バランスが悪化したポリマー組成物となる。
【００６１】
【発明の効果】
本発明のポリマー組成物は、ポリプロピレン樹脂とポリフェニレンエーテル樹脂および水添ブロック共重合体を含んでなり、水添ブロック共重合体として、特定した構造を有する水添ブロック共重合体を用いたため、従来技術では困難であったポリプロピレン樹脂とポリフェニレンエーテルを含むポリマー組成物の耐熱性、低温耐衝撃性および制振性能が改善される。[0001]
BACKGROUND OF THE INVENTION
The present invention is a polymer composition with excellent balance of oil resistance, chemical resistance, heat resistance, impact resistance, especially vibration damping and low temperature impact resistance, which can be used in the electric / electronic field, automobile field and other various industrial material fields. It is about things.
[0002]
[Prior art]
Polypropylene resins are known to have defects inferior in heat resistance, rigidity, and impact resistance, although they are excellent in moldability, water resistance, oil resistance, acid resistance, alkali resistance and the like.
[0003]
On the other hand, polyphenylene ether is known to have disadvantages inferior in molding processability and oil resistance, although it has low mechanical properties, electrical properties, heat resistance, low temperature properties, low water absorption and excellent dimensional stability.
[0004]
Therefore, in order to compensate for these drawbacks, the concept of polymer alloy in which polyphenylene ether resin is blended with polypropylene resin, polypropylene resin forms a matrix and polyphenylene ether resin forms dispersed particles, and these sea-island structures are Many reversed polymer alloy concepts have been proposed.
[0005]
For example, US Pat. No. 3,361,851 proposes to improve solvent resistance and impact resistance by blending polyphenylene ether with polyolefin, and US Pat. No. 3,994,856 discloses polyphenylene ether or polyphenylene. US Pat. No. 4,145,377 describes the improvement of impact resistance and solvent resistance by blending ether and styrenic resin with hydrogenated block copolymer. US Pat. No. 4,145,377 discloses polyphenylene ether or polyphenylene ether and styrenic resin. Of polyolefin / hydrogenated block copolymer = 20 to 80 parts by weight / 80 to 20 parts by weight of a premix and a hydrogenated block copolymer to improve impact resistance and solvent resistance. And US Patent No. 4 66055 Pat and in U.S. Pat. No. 4,239,673, the improvement of impact resistance by blending a hydrogenated block copolymer and polyolefin polyphenylene ethers. U.S. Pat. No. 4,383,082 and European published patent No. 115712 describe that impact resistance is improved by blending polyphenylene ether with a polyolefin and a hydrogenated block copolymer.
[0006]
Also, JP-A-63-113058, JP-A-63-225642, US Pat. No. 4,863,997, JP-A-2-305814, JP-A-3-72512, and JP-A-4-183748. JP-A-5-320471 discloses a resin composition excellent in chemical resistance and processability by blending a specific hydrogenated block copolymer with a modification of a resin composition comprising a polyolefin resin and a polyphenylene ether resin. Things have been proposed.
[0007]
Further, JP-A-7-165998 uses a hydrogenated block copolymer in which the bond form of a conjugated diene compound is specified as a compatibility modifier for a resin composition comprising a polyphenylene ether resin and a polyolefin resin. It has been proposed.
[0008]
[Problems to be solved by the invention]
In recent years, in the field of information equipment, as the information processing capacity and processing speed have increased significantly, the drive unit has been required to rotate at a high speed. In addition to noise reduction, the worst case may cause media data reading errors and malfunctions, so the plastic materials used in these devices are required to have damping performance at room temperature. is there.
[0009]
Furthermore, the present situation is that almighty performance that sufficiently satisfies heat resistance, impact resistance, workability and the like as basic performance as a plastic material, and also excellent in low temperature impact strength is required.
[0010]
In particular, among the resin compositions obtained by the above-described prior art, some of them give a resin composition having excellent vibration damping performance and low temperature impact strength. A composition having inferior strength or excellent low-temperature impact strength has problems such as inferior vibration damping performance. In view of the current situation, an object of the present invention is to provide a polymer composition including a polypropylene resin and a polyphenylene resin, which have excellent vibration damping performance and low temperature impact strength.
[0011]
[Means for Solving the Problems]
In order to impart a high level of compatibility to a composition comprising a polypropylene resin and a polyphenylene ether resin, and to impart vibration damping performance and low temperature impact, the present inventors have added a hydrogenated block copolymer that can be used as an admixture. As a result of extensive studies on polymers, hydrogenated block copolymers having a specific structure are used as admixtures for compositions containing polypropylene resins and polyphenylene ether resins, resulting in polymer compositions with improved delamination. Furthermore, the present invention has been completed by finding that a polymer composition having a remarkably excellent balance between vibration damping properties and low temperature impact properties, which are contradictory, is obtained.
[0012]
That is, the present invention
(A) Polypropylene resin 5 to 95% by weight
(B) Polyphenylene ether resin 95-5% by weight
For a total of 100 parts by weight of the components (a) and (b),
(C) The block copolymer has a total amount of at least one polymer block A mainly composed of a vinyl aromatic compound and 1,2-vinyl bond amount and 3,4-vinyl bond amount of the conjugated diene compound. The total amount of the polymer block D mainly composed of at least one conjugated diene compound that is less than 5 to 45% and the amount of 1,2-vinyl bonds and 3,4-vinyl bonds of isoprene is 45 to 70%. A hydrogenated block copolymer comprising a polymer block I mainly composed of at least one isoprene and hydrogenating a block copolymer having D / I = 5/95 to 60/40 (weight ratio). A polymer composition comprising 1 to 30 parts by weight of a polymer is provided.
[0013]
The polypropylene resin used as component (a) in the present invention is a crystalline propylene homopolymer, a crystalline propylene homopolymer portion obtained in the first step of polymerization, and propylene, ethylene and / or at least 1 in the second and subsequent steps of polymerization. A crystalline propylene-ethylene block copolymer having a propylene-ethylene random copolymer portion obtained by copolymerizing two other α-olefins (for example, butene-1, hexene-1, etc.), A mixture of a propylene homopolymer and a crystalline propylene-ethylene block copolymer may be used.
[0014]
Such a polypropylene resin is usually used in the presence of a titanium trichloride catalyst or a titanium halide catalyst supported on a carrier such as magnesium chloride and an alkylaluminum compound in a polymerization temperature range of 0 to 100 ° C. and a polymerization pressure of 3 to 100 atm. It is obtained by polymerization in the range of At this time, a chain transfer agent such as hydrogen can be added to adjust the molecular weight of the polymer, and the polymerization method can be either a batch type or a continuous type, butane, pentane, hexane, heptane. Further, methods such as solution polymerization in a solvent such as octane and slurry polymerization can also be selected. Furthermore, bulk polymerization in a monomer in the absence of a solvent, gas phase polymerization method in a gaseous monomer, and the like can be applied.
[0015]
Furthermore, in addition to the polymerization catalyst described above, an electron donating compound can be used as an internal donor component or an external donor component as a third component in order to increase the isotacticity and polymerization activity of the polypropylene obtained.
[0016]
As these electron-donating compounds, known compounds can be used, for example, ester compounds such as ε-caprolactone, methyl methacrylate, ethyl benzoate, methyl toluate, triphenyl phosphite, tributyl phosphite and the like. Phosphoric acid derivatives such as phosphate esters and hexamethylphosphoric triamide, alkoxy ester compounds, aromatic monocarboxylic acid esters and / or aromatic alkyl alkoxy silanes, aliphatic hydrocarbon alkoxy silanes, various ether compounds, various alcohols And / or various phenols.
[0017]
As long as the polypropylene resin provided by the present invention can be obtained by the above-described method, any resin having any crystallinity or melting point can be used alone or in combination of two or more.
[0018]
In addition to the polypropylene resin described above, the polypropylene resin used in the present invention is a solution in which the polypropylene resin and an α, β-unsaturated carboxylic acid or derivative thereof are in a molten state in the presence or absence of a radical generator. Even if it is a well-known modification | denaturation (this (alpha), (beta)-unsaturated carboxylic acid or its derivative is 0.01 to 10 weight% graft | grafting or addition)) polypropylene resin obtained by making it react at the temperature of 30-350 degreeC in a state Further, it may be a mixture of the above-described polypropylene resin and the modified polypropylene resin in an arbitrary ratio.
[0019]
The component (b) polyphenylene ether resin (hereinafter simply abbreviated as PPE) used in the present invention is an essential component for imparting heat resistance and flame retardancy to the polymer composition of the present invention. Is a bond unit:
[0020]
[Chemical 1]

[0021]
(Where R ₁ , R ₂ , R _Three , And R _Four Are each a hydrogen atom, a halogen atom, a primary or secondary lower alkyl group having 1 to 7 carbon atoms, a phenyl group, a haloalkyl group, an aminoalkyl group, a hydrocarbonoxy group or at least two carbon atoms as a halogen atom. It is selected from the group consisting of halohydrocarbonoxy groups separating oxygen atoms and may be the same or different from each other, and reduced viscosity (0.5 g / dl, chloroform solution, measured at 30 ° C.) ) Is a homopolymer and / or copolymer in the range of 0.15 to 0.70, more preferably in the range of 0.20 to 0.60.
[0022]
Specific examples of the PPE include poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4-phenylene ether), and poly (2-methyl ether). -6-phenyl-1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether) and the like, and 2,6-dimethylphenol and other phenols (for example, 2,6- Polyphenylene ether copolymers such as copolymers with 3,6-trimethylphenol and 2-methyl-6-butylphenol) may also be mentioned. Of these, poly (2,6-dimethyl-1,4-phenylene ether) and a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol are preferable, and poly (2,6-dimethyl-1 , 4-phenylene ether).
[0023]
The method for producing such PPE is not particularly limited as long as it can be obtained by a known method. For example, a complex of cuprous salt and amine by Hay described in US Pat. No. 3,306,874 is used as a catalyst, for example, 2 , 6-xylenol can be easily produced by oxidative polymerization. In addition, U.S. Pat. Nos. 3,306,875, 3,257,357 and 3,257,358, JP-B-52-17880, and JP-A-50-51197 and It can be easily produced by the method described in 63-152628.
[0024]
In addition to the PPE described above, the PPE used in the present invention melts the PPE and a styrene monomer and / or an α, β-unsaturated carboxylic acid or derivative thereof in the presence or absence of a radical generator. A known modification obtained by reacting at 80 to 350 ° C. in a state, a solution state or a slurry state (the styrenic monomer and / or α, β-unsaturated carboxylic acid or derivative thereof is 0.01 to 10%). (Weight% grafting or addition) PPE may be used, and it may be a mixture of the above-mentioned PPE and the modified PPE in an arbitrary ratio.
[0025]
Further, as the PPE used in the present invention, in addition to the above-mentioned PPE, those obtained by adding polystyrene or high-impact polystyrene within a range not exceeding 400 parts by weight to 100 parts by weight of these PPEs can be suitably used.
[0026]
Next, the hydrogenated block copolymer used as the component (c) in the present invention is obtained when the polypropylene resin as the component (a) and the polyphenylene ether resin as the component (b) are melt-mixed. Is a hydrogenated block copolymer having the ability to suitably finely disperse in the component (a) polypropylene resin or to suitably finely disperse the component (a) polypropylene resin in the component (b) polyphenylene ether resin. is there. That is, in the present invention, the block copolymer comprises at least one polymer block A mainly composed of a vinyl aromatic compound, and the 1,2-vinyl bond amount and 3,4-vinyl bond amount of the conjugated diene compound. The total amount of the polymer block D mainly composed of at least one conjugated diene compound having a total amount of less than 5 to 45% and the amount of 1,2-vinyl bonds and 3,4-vinyl bonds of isoprene is 45 to 45%. Water formed by hydrogenating a block copolymer composed of a polymer block I mainly composed of at least one isoprene that is 70% and having D / I = 5 / 95-60 / 40 (weight ratio) It is a block copolymer.
[0027]
Examples of the hydrogenated block copolymer having such a structure include A-D-I, A-D-I-A, A-I-A-D, A-I-A-I-D, and A. -D-A-I-A, D-A-I, D-A-D-I, D-A-D-A-I, D-A-D-A-D-I and the like. .
[0028]
Here, the total amount of 1,2-vinyl bonds or 3,4-vinyl bonds in the polymer block D mainly composed of the conjugated diene compound before hydrogenation (hereinafter abbreviated as vinyl bond) is: It is less than 5-45%, preferably less than 10-45%, more preferably less than 30-45%. When the vinyl bond content of the polymer block D is 45% or more, the miscibility of the polypropylene resin and the polyphenylene ether resin is improved, but the low temperature impact strength of the resulting polymer composition is remarkably lowered, which is not preferable.
[0029]
The total amount of 1,2-vinyl bonds or 3,4-vinyl bonds in the polymer block I mainly composed of isoprene before hydrogenation (hereinafter abbreviated as vinyl bond amount) is 45 to 70. %, Preferably 45 to 60%, more preferably 48 to 58%. When the amount of vinyl bonds in the polymer block I is less than 45%, the miscibility of the polypropylene resin and the polyphenylene ether resin is reduced, and the resulting polymer composition is preferably peeled off or the vibration damping performance is extremely deteriorated. Absent. Further, even when the vinyl bond amount exceeds 70%, the miscibility of the polypropylene resin and the polyphenylene ether resin is not significantly improved, and the vibration damping performance is not significantly improved.
[0030]
These 1,2-vinyl bond amounts or 3,4-vinyl bond amounts can be usually known by an infrared spectrophotometer or NMR.
[0031]
In the hydrogenated block copolymer of component (C), the polymer block D and the polymer block I must satisfy D / I = 5/95 to 60/40 (weight ratio). When D is less than 5%, the low temperature impact strength is remarkably lowered. When D exceeds 40%, the low temperature impact strength is excellent, but the vibration damping property is remarkably undesirably lowered.
[0032]
This hydrogenated block copolymer of component (C) is 15 to 95% by weight, preferably 20 to 70% by weight, more preferably 35% of the vinyl aromatic compound bonded in the block copolymer before hydrogenation. Contains ~ 50% by weight.
[0033]
In addition, referring to the block structure, the polymer block A mainly composed of a vinyl aromatic compound contains a homopolymer block of a vinyl aromatic compound or a vinyl aromatic compound in an amount of more than 50% by weight, preferably 70% by weight or more. The polymer block D has a copolymer block structure of a vinyl aromatic compound and a conjugated diene compound, and the polymer block D mainly composed of the conjugated diene compound is a homopolymer block of a conjugated diene compound or a conjugated diene It has a structure of a copolymer block of a conjugated diene compound and a vinyl aromatic compound containing more than 50% by weight of the compound and preferably 70% by weight or more.
[0034]
The polymer block I mainly composed of isoprene is a homopolymer block of isoprene or isoprene containing more than 50% by weight, preferably 70% by weight or more of isoprene, a vinyl aromatic compound, and a conjugated diene compound other than isoprene. It has a copolymer block structure.
[0035]
Further, a polymer block A mainly composed of these vinyl aromatic compounds, a polymer block D mainly composed of a conjugated diene compound, and a polymer block I mainly composed of isoprene are included in the molecular chain in each polymer block. The distribution of the conjugated diene compound or the vinyl aromatic compound may be random, tapered (in which the monomer component increases or decreases along the molecular chain), partially blocky, or any combination thereof. The polymer block A mainly composed of an aromatic compound, the polymer block D mainly composed of the conjugated diene compound, and the polymer block I mainly composed of isoprene are each at least one, and each polymer block has the same structure. It may be a different structure.
[0036]
As the vinyl aromatic compound constituting the block copolymer, for example, one or more kinds can be selected from styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, diphenylethylene, and the like. Of these, styrene is preferred. Further, as the conjugated diene compound, for example, one or more kinds are selected from butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, etc., among which butadiene, isoprene and These combinations are preferred.
[0037]
The number average molecular weight of the block copolymer having the above structure is in the range of 5,000 to 1,000,000, preferably 10,000 to 800,000, more preferably 30,000 to 500,000. The molecular weight distribution [ratio of weight average molecular weight (Mw) and number average molecular weight (Mn) converted by monodisperse polystyrene molecular weight measured by gel permeation chromatography and used as a calibration curve] is 10 or less. Further, the molecular structure of the block copolymer may be linear, branched, radial, or any combination thereof.
[0038]
The block copolymer having such a structure is obtained by hydrogenating the aliphatic double bond of the polymer block D mainly composed of the conjugated diene compound of the block copolymer and the polymer block I mainly composed of isoprene. The hydrogenated block copolymer can be used as the component (c) of the present invention. The hydrogenation rate of such aliphatic double bonds exceeds at least 60%, preferably 80% or more, more preferably 85% or more from the viewpoint of heat resistance stability. This hydrogenation rate can usually be known with an infrared spectrophotometer, NMR, or the like.
[0039]
These hydrogenated block copolymers of the component (c) may be obtained by any production method as long as they have the structure described above. Examples of known production methods include, for example, JP-A-47-11486, JP-A-49-66743, JP-A-50-75651, JP-A-54-126255, JP-A-54-126255. No. 56-10542, Japanese Patent Laid-Open No. 56-62847, Japanese Patent Laid-Open No. 56-1000084, Japanese Patent Laid-Open No. 2-300218, British Patent No. 1130770, and US Pat. Nos. 3,281,383 and 3639517 And methods described in British Patent No. 1020720 and US Pat. Nos. 3,333,024 and 4,501,857.
[0040]
The hydrogenated block copolymer of component (c) used in the present invention includes the hydrogenated block copolymer and an α, β-unsaturated carboxylic acid or derivative thereof in addition to the hydrogenated block copolymer described above. In the presence or absence of a radical generator in the molten state, solution state, or slurry state at a temperature of 80 to 350 ° C., a known modification (the α, β-unsaturated carboxylic acid or The derivative may be a 0.01 to 10% by weight graft or addition) hydrogenated block copolymer, and a mixture of the above-mentioned hydrogenated block copolymer and the modified hydrogenated block copolymer in an arbitrary ratio. It doesn't matter.
[0041]
The polymer composition of the present invention comprises the above-described components (a) to (c) as basic components. (A) The compounding quantity of the polypropylene resin of a component is 5-95 weight%, Preferably it is 10-90 weight%. If the blending amount is less than 5% by weight, the polymer composition obtained is excellent in heat resistance, but is unfavorable because of poor molding processability and solvent resistance. On the other hand, if it exceeds 95% by weight, the moldability and solvent resistance are good, but the heat resistance is poor and it cannot be used as a heat resistant material.
[0042]
The blending amount of the polyphenylene ether as component (b) is 95 to 5% by weight, preferably 90 to 10% by weight. When the blending amount exceeds 95% by weight, the resulting polymer composition has extremely high heat resistance, but is inferior in molding processability and solvent resistance. On the other hand, if it is less than 5% by weight, the moldability and solvent resistance are excellent, but the heat resistance is inferior and cannot be used as a heat resistant material.
[0043]
(C) The compounding quantity of the hydrogenated block copolymer of a component is 1-30 weight part with respect to a total of 100 weight part of said (a), (b) component. If the blending amount is less than 1 part by weight, the effect as an admixture, the damping effect and the low temperature impact strength improvement effect are not seen, which is not preferable. Further, even when the blending amount exceeds 30 parts by weight, the effect of improving the vibration damping property and the low temperature impact strength is not remarkable, and conversely, the heat and solvent resistance of the effects shown by the components (a) and (b) This is undesirable because it causes a decrease in rigidity and mechanical strength.
[0044]
In the present invention, in addition to the above-mentioned components, other additional components as necessary, for example, a styrene-butadiene block copolymer having a bound styrene content of 10 to 90%, as long as the features and effects of the present invention are not impaired. Water having a structure different from that of the present invention in which 80% or more of an aliphatic double bond resulting from a styrene-isoprene block copolymer having a bound styrene content of 10 to 90% and a conjugated diene compound of these block copolymers is hydrogenated Added block copolymer, antioxidant, metal deactivator, flame retardant (organic phosphate ester compound, inorganic phosphorus compound, aromatic halogen flame retardant, silicone flame retardant, etc.), fluorine polymer, plastic Agents (oil, low molecular weight polyethylene, epoxidized soybean oil, polyethylene glycol, fatty acid esters, etc.), flame retardant aids such as antimony trioxide, weather resistance ( ) Property improver, polyolefin nucleating agent, slip agent, inorganic or organic filler or reinforcing material (glass fiber, carbon fiber, polyacrylonitrile fiber, whisker, mica, talc, carbon black, titanium oxide, calcium carbonate, titanium Potassium acid, wollastonite, conductive metal fiber, conductive carbon black, etc.), various colorants, release agents and the like may be added.
[0045]
The polymer composition of the present invention is a method in which the components (b) and (c) previously melt-kneaded using the components described above are melt-kneaded together with the components (a), A method in which a part is pre-kneaded with the components (a) and (b) in advance and these pre-kneaded materials are melted and kneaded together again. The components (b) and (c) are supplied from the first feed port of the extruder. And it can manufacture by various methods, such as the method of supplying (a) component to these compositions of a molten state from the intermediate port of an extruder, and melt-kneading. Examples of these methods include a hot melt kneading method using a single screw extruder, a twin screw extruder, a roll, a kneader, a Brabender plastograph, a Banbury mixer, etc. Among them, a melt kneading method using a twin screw extruder is used. Most preferred. Although the melt kneading temperature in this case is not particularly limited, it can usually be arbitrarily selected from 200 to 350 ° C.
[0046]
The polymer composition of the present invention thus obtained can be molded as molded parts of various parts by various conventionally known methods such as injection molding, extrusion molding and hollow molding. Examples of these various parts include automobile parts. Specifically, bumpers, fenders, door panels, various moldings, emblems, engine hoods, wheel caps, roofs, spoilers, various aero parts, and other exterior parts, Suitable for interior parts such as instrument panels, console boxes and trims. Furthermore, it can also be used suitably as an interior / exterior part of electrical equipment. Specifically, parts such as various computers and peripheral equipment, other office automation equipment, televisions, videos, various disk player cabinets, chassis, trays, refrigerators, etc. Suitable for use.
[0047]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in more detail by way of examples, but is not limited by these examples.
[0048]
Polypropylene resin of component (a) used in the examples
(A): Homo-polypropylene
Melting point = 160 ° C., MFI = 1.6
PPE of component (b) used in the examples
(B): Polyphenylene ether having a reduced viscosity of 0.45 obtained by oxidative polymerization of 2,6-xylenol
Hydrogenated block copolymer of component (c) used in the examples
(C-1): Polystyrene-hydrogenated vinyl bond 36% polybutadiene-hydrogenated vinyl bond 55% polyisoprene structure, bonded styrene content 35%, hydrogenated vinyl bond 36% polybutadiene / hydrogenated vinyl bond 55% polyisoprene = 30/70 (weight ratio), polystyrene number average molecular weight 28000, total hydrogenation ratio of polybutadiene part and polyisoprene part is 89.5% A hydrogenated block copolymer was synthesized, and this polymer was designated as (c-1).
[0049]
(C-2): Similarly, a polyisoprene-polystyrene-hydrogenated vinyl bond 53% polyisoprene-polystyrene structure having a polystyrene-hydrogenated vinyl bond content of 11%, a bonded styrene content of 48%, Polyisoprene with 11% hydrogenated vinyl bond / Polyisoprene with 53% hydrogenated vinyl bond = 50/50 (weight ratio) The number average molecular weights of the two polystyrene blocks are the same 28300, total polyisoprene A hydrogenated block copolymer having a hydrogenation rate of 92.5% in part was synthesized, and this polymer was designated as (c-2).
[0050]
(C-3): Similarly, it has a polybutadiene-polystyrene-hydrogenated vinyl bond amount of 40% polyisoprene-polystyrene structure having a hydrogenated vinyl bond amount of 40%, a bonded styrene amount of 20%, hydrogen Polybutadiene added with 40% vinyl bond / polyisoprene with 58% hydrogenated vinyl bond = 8/92 (weight ratio) The number average molecular weight of the two polystyrene blocks is the same 10,000, polybutadiene part and polyisoprene A hydrogenated block copolymer having a total hydrogenation ratio of 87.1% was synthesized, and this polymer was designated as (c-3).
[0051]
(C-4): Furthermore, it has a polystyrene-hydrogenated polyisoprene structure with a vinyl bond content of 55%, a bond styrene content of 36%, a polystyrene number average molecular weight of 30000, and a total hydrogenation rate of the polyisoprene part. An 85.4% hydrogenated block copolymer was synthesized, and this polymer was designated as (c-4).
[0052]
(C-5): Similarly, a polystyrene-hydrogenated polyisoprene-polystyrene structure having a vinyl bond content of 56%, a bonded styrene content of 21%, and the number average molecular weights of the two polystyrene blocks being 8900, A hydrogenated block copolymer having a total hydrogenation rate of the polyisoprene portion of 84.4% was synthesized, and this polymer was designated as (c-5).
[0053]
In addition, each characteristic of the obtained polymer composition was calculated | required by the method shown below.
[0054]
(1) Heat resistance test
Based on ASTM D648, the heat distortion temperature (HDT) was measured at a load of 18.6 kg.
[0055]
(2) Low temperature impact test
In accordance with ASTM D256, an Izod impact strength with a notch of −30 ° C. was measured with an injection molded piece having a thickness of 1/8 inch.
[0056]
(3) Vibration control (loss factor η)
Measurement was performed at a measurement temperature of 23 ° C. by a cantilever method using non-contact random vibration using a two-channel fast Fourier transform device.
[0057]
Examples 1-7 and Comparative Examples 1-6
Polypropylene resin, polyphenylene ether resin, and hydrogenated block copolymer were blended in the composition shown in Table 1, and a twin-screw extruder with a vent port set at 260 to 280 ° C. (ZSK-25; manufactured by WERNER & PFLIDELER, Germany) And kneaded to obtain pellets.
[0058]
The pellets were supplied to a screw in-line injection molding machine set at 240 to 280 ° C., and an Izod impact test piece and a heat distortion temperature measurement test piece were injection molded under a mold temperature of 60 ° C. Further, a test piece for measuring vibration damping performance was injection molded with a thickness of 1/8 inch, a width of 0.5 inch, and a length of 5 inches. These test pieces were measured for thermal deformation temperature (HDT), low-temperature Izod impact strength, and vibration damping performance by the methods described above. These results are shown together in Table 1.
[0059]
[Table 1]

[0060]
From these results, in the polymer block mainly composed of the conjugated diene compound constituted as the hydrogenated block copolymer, the total amount of 1,2-vinyl bond amount and 3,4-vinyl bond amount is 5 to 45. % Of polymer block D mainly composed of at least one conjugated diene compound and less than 1%, and the total amount of 1,2-vinyl bonds and 3,4-vinyl bonds in isoprene is 45 to 70%. By using a hydrogenated block copolymer having a polymer block I mainly composed of individual isoprene, a polymer composition having an excellent balance between vibration damping properties, low temperature impact strength and heat distortion temperature can be obtained. Further, a polymer block mainly composed of a conjugated diene compound as a hydrogenated block copolymer outside the present invention simply has a total amount of 1,2-vinyl bonds and 3,4-vinyl bonds of isoprene of 45 to 70. %, When a hydrogenated block copolymer composed only of the polymer block I mainly composed of at least one isoprene is used, the vibration damping performance is excellent, but the low-temperature impact strength is extremely deteriorated. In addition, even if many hydrogenated block copolymers other than the present invention are blended in order to increase the low temperature impact strength, significant improvement in vibration damping performance and low temperature impact strength cannot be expected. ) Is greatly reduced, resulting in a polymer composition having a deteriorated physical property balance.
[0061]
【The invention's effect】
The polymer composition of the present invention comprises a polypropylene resin, a polyphenylene ether resin, and a hydrogenated block copolymer. Since the hydrogenated block copolymer having the specified structure is used as the hydrogenated block copolymer, the conventional polymer composition is used. The heat resistance, low-temperature impact resistance, and vibration damping performance of a polymer composition containing polypropylene resin and polyphenylene ether, which has been difficult in the art, are improved.

Claims (1)

In the polymer composition:
(A) Polypropylene resin 5 to 95% by weight
(B) Polyphenylene ether resin 95-5% by weight
For a total of 100 parts by weight of the components (a) and (b),
(C) The block copolymer has a total amount of at least one polymer block A mainly composed of a vinyl aromatic compound and 1,2-vinyl bond amount and 3,4-vinyl bond amount of the conjugated diene compound. The total amount of the polymer block D mainly composed of at least one conjugated diene compound that is less than 5 to 45% and the amount of 1,2-vinyl bonds and 3,4-vinyl bonds of isoprene is 45 to 70%. A hydrogenated block copolymer comprising a polymer block I mainly composed of at least one isoprene and hydrogenating a block copolymer having D / I = 5/95 to 60/40 (weight ratio). A polymer composition comprising 1 to 30 parts by weight of a polymer.