JP3549624B2 - Thermoplastic resin composition - Google Patents

Description

（式中、Ｒは上記のモノカルボン酸からカルボキシル基を除いた残基であり、好ましくはアルキル基、シクロアルキル基、アリール基、アラルキル基である。）
【００２２】
末端封止剤として使用されるモノアミンとしては、カルボキシル基との反応性を有するものであれば特に制限はないが、例えば、メチルアミン、エチルアミン、プロピルアミン、ブチルアミン、ヘキシルアミン、オクチルアミン、デシルアミン、ステアリルアミン、ジメチルアミン、ジエチルアミン、ジプロピルアミン、ジブチルアミンなどの脂肪族モノアミン；シクロヘキシルアミン、ジシクロヘキシルアミンなどの脂環式モノアミン；アニリン、トルイジン、ジフェニルアミン、ナフチルアミンなどの芳香族モノアミン、あるいはこれらの任意の混合物を挙げることができる。これらのうち、反応性、沸点、封止末端の安定性および価格などの点から、ブチルアミン、ヘキシルアミン、オクチルアミン、デシルアミン、ステアリルアミン、シクロヘキシルアミン、アニリンが特に好ましい。
【００２３】
ポリアミドの末端基をモノアミンで封止する場合は、ポリアミドの製造に際してジカルボン酸成分に対するジアミン成分の使用モル数をわずかに少なくして、ポリアミドの両末端がカルボキシル基になるようにし、モノアミンを末端封止剤として加えるのがよい。
【００２４】
ポリアミドのカルボキシル基末端は、これらのモノアミンで封止されることにより、下記の一般式（ＩＩ）で示される封止末端を形成する。
【００２５】
【化２】

（式中、Ｒ^１は上記のモノアミンからアミノ基を除いた残基であり、好ましくはアルキル基、シクロアルキル基、アリール基、アラルキル基である。Ｒ^２は水素原子または上記のモノアミンからアミノ基を除いた残基であり、好ましくは水素原子、アルキル基、シクロアルキル基、アリール基、アラルキル基である。）
【００２６】
ポリアミドを製造する際に用いられる末端封止剤の使用量は、用いる末端封止剤の反応性、沸点、反応装置、反応条件などによって変化するが、通常、ジカルボン酸とジアミンの総モル数に対して０．１〜１５モル％の範囲内で使用されるのが好ましい。
【００２７】
本発明に用いられるポリアミドは、従来よりポリアミドを製造する方法として知られている、溶融重合法、溶液重合法、反応型押出機を使用する重合法などの方法を用いて製造することができる。本発明者らの研究によれば、触媒および必要に応じて末端封止剤を、最初にジアミンおよびジカルボン酸に一括して添加し、ナイロン塩を製造した後、いったん２８０℃以下の温度において濃硫酸中３０℃における極限粘度［η］が０．１０〜０．６０ｄｌ／ｇのプレポリマーとし、さらに固相重合するか、あるいは溶融押出機を用いて重合を行うことにより、容易にポリアミドを得ることができる。プレポリマーの極限粘度［η］が０．１０〜０．６０ｄｌ／ｇの範囲内であると、後重合の段階においてカルボキシル基とアミノ基のモルバランスのずれや重合速度の低下が少なく、さらに分子量分布の小さな、各種性能や成形性に優れたポリアミドが得られる。重合の最終段階を固相重合により行う場合、減圧下または不活性ガス流通下に行うのが好ましく、重合温度が１８０〜２８０℃の範囲内であれば、重合速度が大きく、生産性に優れ、着色やゲル化を有効に押さえることができるので好ましい。重合の最終段階を溶融押出機により行う場合、重合温度が３７０℃以下であるとポリアミドの分解がほとんどなく、劣化の無いポリアミドが得られるので好ましい。
【００２８】
ポリアミドの製造の際に用いることができる触媒としては、リン酸、亜リン酸、次亜リン酸、またはそれらのアンモニウム塩、それらの金属塩（カリウム、ナトリウム、マグネシウム、バナジウム、カルシウム、亜鉛、コバルト、マンガン、錫、タングステン、ゲルマニウム、チタン、アンチモンなどの金属塩）、それらのエステル類（エチルエステル、イソプロピルエステル、ブチルエステル、ヘキシルエステル、イソデシルエステル、オクタデシルエステル、デシルエステル、ステアリルエステル、フェニルエステル）などを挙げることができる。
【００２９】
本発明に用いられるポリアミドは、濃硫酸中３０℃で測定した極限粘度［η］が０．４〜３．０ｄｌ／ｇの範囲内であり、０．６〜２．０ｄｌ／ｇの範囲内のものが好ましく、０．８〜１．６ｄｌ／ｇの範囲内のものがより好ましい。ポリアミドの極限粘度［η］が上記の範囲内であれば、成形性に優れるだけでなく、力学特性、耐熱特性などの諸物性に優れた熱可塑性樹脂組成物が得られる。
【００３０】
本発明に用いられるポリアミドは、極限粘度［η］が０．４〜３．０ｄｌ／ｇの範囲内で、極限粘度［η］と剪断速度１０００ｓ^−１で測定した溶融粘度（ＭＶ）との間に、下記の式（２）で示される関係が成立する。
ｌｏｇＭＶ＝１．９［η］＋Ａ ………（２）
（ここでＡは温度により変化する数である。）
【００３１】
本発明に用いられる好ましいポリアミドの場合、３４０℃でのＡ値は０．６〜１．０であり、３３０℃でのＡ値と３５０℃でのＡ値との差は０．１〜０．６である。一方、従来のＰＡ６−Ｔ系ポリアミドの場合、極限粘度［η］の係数は本発明に用いられるポリアミドとほぼ同じであるが、３４０℃でのＡ値は１．３〜１．７であり、３３０℃でのＡ値と３５０℃でのＡ値との差は０．７〜１．１である。このように、成形温度として好ましい３３０〜３５０℃において、本発明に用いられるポリアミドは従来のＰＡ６−Ｔ系ポリアミドに比較して、同じ極限粘度［η］であっても溶融粘度が小さく、成形温度の変化にともなう溶融粘度の変化も小さい。さらに、本発明に用いられるポリアミドは、成形時の滞留時間中での溶融粘度の変化が小さいという特性をも有しており、従来のＰＡ６−Ｔ系ポリアミドに比較すると成形性が顕著に向上している。
【００３２】
本発明の熱可塑性樹脂組成物は、上記のポリアミドに、溶融液晶高分子を特定量配合させる必要ある。溶融液晶高分子を特定量配合させることにより、力学強度、低吸水性、耐薬品性などに優れた熱可塑性樹脂組成物が得られる。溶融液晶高分子の配合割合は、ポリアミド１００重量部に対して、０．１〜２００重量部である必要があり、０．５〜１５０重量部であるのが好ましく、１〜１００重量部であるのがより好ましい。
【００３３】
本発明に用いられる溶融液晶高分子は、溶融相において液晶を形成する（すなわち光学的異方性を示す）性質を有しており、ペンタフルオロフェノール中６０℃で測定した極限粘度［η］が０．１〜５ｄｌ／ｇであるのが好ましい。溶融相におけるこのような光学的異方性の確認は、加熱装置を備えた偏光顕微鏡を用いて、直交ニコル下で試料の薄片、好ましくは厚み５〜２０μｍ程度の薄片をカバーグラス間に挟み、一定の昇温速度下で観察し、一定の温度以上で光を透過することを見ることにより行い得る。なお、観察中に、高温度下でカバーグラス間に挟んだ試料に軽く圧力を加えるか、あるいはカバーグラスをずり動かすことによって、より確実に偏光の透過を観察し得る。偏光の透過し始める温度が、光学的に異方性の溶融相への転移温度であり、本発明に用いられる溶融液晶高分子の転移温度は、溶融成形の容易さの点から４００℃以下であることが好ましく、３５０℃以下であることがより好ましい。
【００３４】
本発明に用いられる溶融液晶高分子は、上記の条件を満たすものなら特にその構造を問わないが、代表的な例として、実質的に芳香族ヒドロキシカルボン酸単位からなるポリエステル；実質的に芳香族ヒドロキシカルボン酸単位、芳香族ジカルボン酸単位および芳香族ジオール単位からなるポリエステル；実質的に芳香族ヒドロキシカルボン酸単位、芳香族ジカルボン酸単位および脂肪族ジオール単位からなるポリエステル；実質的に芳香族ヒドロキシカルボン酸単位および芳香族アミノカルボン酸単位からなるポリエステルアミド；実質的に芳香族ヒドロキシカルボン酸単位、芳香族ジカルボン酸単位および芳香族ジアミン単位からなるポリエステルアミド；実質的に芳香族ヒドロキシカルボン酸単位、芳香族アミノカルボン酸単位、芳香族ジカルボン酸単位および芳香族ジオール単位からなるポリエステルアミド；実質的に芳香族ヒドロキシカルボン酸単位、芳香族アミノカルボン酸単位、芳香族ジカルボン酸単位、脂肪族ジオール単位からなるポリエステルアミドなどを挙げることができる。
【００３５】
溶融液晶高分子を構成する芳香族ヒドロキシカルボン酸単位としては、例えば、ｐ−ヒドロキシ安息香酸、ｍ−ヒドロキシ安息香酸、６−ヒドロキシ−２−ナフトエ酸、７−ヒドロキシ−２−ナフトエ酸などから誘導される単位を挙げることができる。芳香族アミノカルボン酸単位としては、ｐ−アミノ安息香酸、ｍ−アミノ安息香酸、６−アミノ−２−ナフトエ酸、７−アミノ−２−ナフトエ酸などから誘導される単位を挙げることができる。芳香族ジカルボン酸単位としては、テレフタル酸、イソフタル酸、クロロ安息香酸、４，４’−ビフェニルジカルボン酸、２，６−ナフタレンジカルボン酸、２，７−ナフタレンジカルボン酸、４，４’−オキシジ安息香酸、ジフェニルメタン−４，４’−ジカルボン酸、ジフェニルスルホン−４，４’−ジカルボン酸などから誘導される単位を挙げることができる。芳香族ジオール単位としては、ヒドロキノン、レゾルシノール、メチルヒドロキノン、クロロヒドロキノン、フェニルヒドロキノン、４，４’−ジヒドロキシビフェニル、２，６−ジヒドロキシナフタレン、２，７−ジヒドロキシナフタレン、４，４’−ジヒドロキシジフェニルエーテル、４，４’−ジヒドロキシジフェニルメタン、４，４’−ジヒドロキシジフェニルスルホンなどから誘導される単位を挙げることができる。脂肪族ジオール単位としては、エチレングリコール、プロピレングリコール、１，４−ブタンジオール、１，５−ペンタンジオール、１，６−ヘキサンジオール、１，７−ヘプタンジオール、１，８−オクタンジオール、１，９−ノナンジオール、１，１０−デカンジオール、１，１１−ウンデカンジオール、１，１２−ドデカンジオールなどから誘導される単位を挙げることができる。芳香族ジアミン単位としては、ｐ−フェニレンジアミン、ｍ−フェニレンジアミン、４，４’−ジアミノビフェニル、２，６−ジアミノナフタレン、２，７−ジアミノナフタレンなどから誘導される単位を挙げることができる。
【００３６】
本発明に用いられる溶融液晶高分子の好ましい例としては、例えば、ｐ−ヒドロキシ安息香酸単位および６−ヒドロキシ−２−ナフトエ酸単位からなるポリエステル；ｐ−ヒドロキシ安息香酸単位、４，４’−ジヒドロキシビフェニル単位およびテレフタル酸単位からなるポリエステル；ｐ−ヒドロキシ安息香酸単位、エチレングリコール単位およびテレフタル酸単位からなるポリエステル；ｐ−ヒドロキシ安息香酸単位、６−ヒドロキシ−２−ナフトエ酸単位およびｐ−アミノ安息香酸単位からなるポリエステルアミドなどを挙げることができる。
【００３７】
上記の熱可塑性樹脂組成物１００重量部に対して、さらに充填剤を１〜２００重量部配合することができる。このような割合で充填剤を配合することにより、成形性、力学特性、熱変形温度などの特性がより向上した熱可塑性樹脂組成物が得られるので好ましい。充填剤の配合割合は、ポリアミド１００重量部に対して、１〜１５０重量部であるのがより好ましく、２〜１００重量部であるのがさらに好ましい。
【００３８】
充填剤としては、従来より知られている粉末状、繊維状、クロス状などの各種形態を有する充填剤を用いることができる。
【００３９】
粉末状充填剤としては、シリカ、シリカアルミナ、アルミナ、酸化チタン、酸化亜鉛、窒化ホウ素、タルク、マイカ、チタン酸カリウム、ケイ酸カルシウム、硫酸マグネシウム、ホウ酸アルミニウム、アスベスト、ガラスビーズ、カーボンブラック、グラファイト、二硫化モリブデン、ポリテトラフルオロエチレンなどを挙げることができる。このような粉末状充填剤としては、通常、平均粒径が０．１μｍ〜２００μｍの範囲ものを用いるのが好ましく、１μｍ〜１００μｍの範囲のものを用いるのがより好ましい。これらの粉末状充填剤を用いると、熱可塑性樹脂組成物から得られる成形品の寸法安定性、機械特性、耐熱特性、物理化学的特性、摺動特性などが向上する。
【００４０】
繊維状充填剤としては、ポリパラフェニレンテレフタルアミド繊維、ポリメタフェニレンテレフタルアミド繊維、ポリパラフェニレンイソフタルアミド繊維、ポリメタフェニレンイソフタルアミド繊維、ジアミノジフェニルエーテルとテレフタル酸またはイソフタル酸との縮合物から得られる繊維などの全芳香族ポリアミド繊維、全芳香族液晶ポリエステル繊維などの有機系の繊維状充填剤；あるいはガラス繊維、炭素繊維またはホウ素繊維などの無機系の繊維状充填剤が挙げられる。このような繊維状充填剤を使用すると、熱可塑性樹脂組成物から得られる成形品の力学強度が向上するだけでなく、寸法安定性、低吸水性などが向上するので好ましい。このような繊維状充填剤としては、通常、平均長が０．０５〜５０ｍｍの範囲のものを用いるのが好ましい。さらに、成形性が良好であり、得られる成形品の摺動特性、耐熱性、機械的特性がより向上する点で、平均長が１〜１０ｍｍの範囲のものを用いるのがより好ましい。これらの繊維状充填剤は、クロス状などに二次加工されていてもよい。
【００４１】
これらの充填剤は、１種または２種以上混合して使用することができる。特に、上記の繊維状充填剤と、粉末状充填剤とを組合わせて使用することにより、成形性、表面美麗性、力学特性、および耐熱性がより優れた熱可塑性樹脂組成物を得ることができるので好ましい。また、これらの充填剤として、シランカップリング剤あるいはチタンカップリング剤などで表面処理した物を使用することもできる。充填剤の表面をこれらのカップリング剤で処理したものを使用すると、得られる成形品の力学特性が優れる点で好ましい。シランカップリング剤のなかでも、得られる成形品の力学特性が特に優れることから、アミノシラン系のカップリング剤を使用することがより好ましい。
【００４２】
その他必要に応じて、銅化合物などの安定剤；着色剤；紫外線吸収剤；光安定化剤；ヒンダードフェノール系、ヒンダードアミン系、リン系、チオ系などの酸化防止剤；帯電防止剤；臭素化ポリマー、酸化アンチモン、金属水酸化物などの難燃剤；結晶核剤；可塑剤；潤滑剤、スリップ防止剤、アンチブロッキング剤、防曇剤、顔料、染料、天然油、合成油およびワックスなどをポリアミドの重縮合反応時、またはその後に添加することもできる。
【００４３】
本発明の熱可塑性樹脂組成物は、上記のポリアミドと溶融液晶高分子とを、さらに、必要に応じて上記の充填剤や添加剤を、所望の方法で混合することにより製造することができる。例えば、樹脂材料の混合に通常用いられるような縦型または水平型の混合機を用いて予備混合した後、一軸または二軸の押出機、ニーダー、ミキシングロール、バンバリーミキサーなどの混練装置を用いて、加熱下に溶融混練することにより、本発明の熱可塑性樹脂組成物が製造される。
【００４４】
上記のようにして製造した樹脂組成物を用いて、通常の溶融成形法、例えば、圧縮成形法、射出成形法、押出成形法などにより所望の形状の成形品を製造することができる。
【００４５】
例えば、本発明の熱可塑性樹脂組成物を、シリンダ温度が２８０〜３５０℃に調節された射出成形機のシリンダ内で樹脂を溶融させ、所定の形状の金型内に導入（射出）することにより成形品を製造することができる。また、上記のシリンダ温度に調節された押出機内で熱可塑性樹脂組成物を溶融させ、口金ノズルより紡出することにより、繊維を製造することができる。さらに、上記のシリンダ温度に調節された押出機内で熱可塑性樹脂組成物を溶融させ、Ｔダイから樹脂を押出すことにより、フィルムを製造することができる。さらに、インフレーション成形、吹き込み成形などによってもフィルムやボトルなどの成形品を得ることができる。
【００４６】
上記のような成形品は、さらに表面に塗料、金属層、あるいは他種ポリマーなどで被覆した状態で使用することもできる。
【００４７】
本発明の熱可塑性樹脂組成物からなる成形品としては、例えば、電動工具、一般工業用部品、ギヤ、カムなどの機械部品、コネクタ、スイッチ、リレー、ＭＩＤ、プリント配線板、電子部品のハウジングなどのような電子部品、フィルム、シート、繊維など種々の形態の成形品を挙げることができる。特に、自動車用途の成形品、例えば、自動車の内外装部品、自動車のエンジンルーム内の部品、自動車の電装部品などに好適に使用することができる。
【００４８】
【実施例】
以下、実施例を挙げて本発明を具体的に説明するが、本発明はこれらにより何ら制限されるものではない。なお、以下の例において、ポリアミドの末端封止率、極限粘度、融点；熱可塑性樹脂組成物の溶融粘度；成形品の引張強度、吸水率、線膨脹係数、耐アルコール性、耐熱水性は下記の方法により測定または評価した。
【００４９】
末端封止率：
^１Ｈ−ＮＭＲ（５００ＭＨｚ，重水素化トリフルオロ酢酸中、５０℃で測定）を用い、各末端基ごとの特性シグナルの積分値よりカルボキシル基末端、アミノ基末端および封止末端の数をそれぞれ測定し、前記の式（１）から末端封止率を求めた。測定に用いた代表的なシグナルの化学シフト値を以下に示す。
【００５０】
【表１】

【００５１】
極限粘度［η］：
濃硫酸中、３０℃にて、０．０５，０．１，０．２，０．４ｇ／ｄｌの濃度の試料の固有粘度（ηｉｎｈ ）を測定し、これを濃度０に外挿した値を極限粘度［η］とした。
ηｉｎｈ ＝［ｌｎ（ｔ_１／ｔ_０）］／ｃ
〔式中、ηｉｎｈ は固有粘度（ｄｌ／ｇ）、ｔ_０は溶媒の流下時間（秒）、ｔ_１は試料溶液の流下時間（秒）、ｃは溶液中の試料の濃度（ｇ／ｄｌ）を表す。〕
【００５２】
融点：
示差走査熱量計（メトラー社製「ＤＳＣ３０」）を用いて、試料を１００℃／分の速度で昇温して完全に融解させた後、１０℃／分の降温速度で５０℃まで冷却し、再び１０℃／分の速度で昇温した時に現れる吸熱ピークの位置の温度を測定し、これを融点とした。
【００５３】
溶融流動性：
ＫＡＹＮＥＳＳ製「キャピラリーレオメーター、ＧＡＬＡＸＹＶ ＭＯＤＥＬ８０５２」（ダイ径１ｍｍ、Ｌ／Ｄ＝１０）を使用して、３４０℃における、剪断速度１０００ｓ^−１での溶融粘度（ｐｏｉｓｅ）を測定し、成形加工性の指標とした。
【００５４】
吸水率：
８０×８０×３ｍｍの射出成形品を、２３℃の水中に２４時間浸漬した。浸漬前後の成形品の重量変化から吸水率（％）を求めた。
【００５５】
引張強度：
ＪＩＳ１号ダンベル型射出成形片を用い、ＪＩＳ Ｋ ７１１３に準拠して測定した。
【００５６】
線膨脹係数：
８０×８０×３ｍｍの射出成形品から、３×３×３ｍｍの試験片を作製し、１０℃／分で昇温した時の、５０〜７０℃の温度領域における機械軸方向（ＭＤ方向）の寸法変化を、熱機械分析（ＴＭＡ）装置（メトラー社製「ＴＭＡ４０」）を用いて測定し、下記の式（３）により線膨張係数を求めた。
【００５７】
線膨脹係数（１／℃）＝（Ｌ_１−Ｌ_２）／〔（Ｔ_１−Ｔ_２）×Ｌ_０〕 （３）
（式中、Ｌ_０は初期の試料長（ｍｍ）、Ｌ_１は７０℃における試料長（ｍｍ）、Ｌ_２は５０℃における試料長（ｍｍ）、Ｔ_１は７０（℃）、Ｔ_２は５０（℃）を示す。）
【００５８】
耐アルコール性：
ＪＩＳ１号ダンベル型射出成形片を、２３℃のメタノール中に１週間浸漬した。浸漬前後の成形品の引張強度を測定し、引張強度の保持率（％）を求めた。
【００５９】
耐熱水性：
ＪＩＳ１号ダンベル型射出成形片を、耐圧オートクレーブ中でスチーム処理し（１２０℃、２気圧で１２０時間）、さらにその試料を１２０℃で１２０時間真空乾燥した。処理前後の成形品の引張強度を測定し、引張強度の保持率（％）を求めた。
【００６０】
参考例１
テレフタル酸３２５６．２ｇ（１９．６０モル）、１，９−ノナンジアミン３１６５．８ｇ（２０．０モル）、安息香酸９７．７ｇ（０．８０モル）、次亜リン酸ナトリウム一水和物６．５ｇ（原料に対して０．１重量％）および蒸留水２．２リットルを内容積２０リットルのオートクレーブに入れ、窒素置換した。１００℃で３０分間撹拌し、２時間かけて内部温度を２１０℃に昇温した。この時、オートクレーブは２２ｋｇ／ｃｍ^２まで昇圧した。そのまま１時間反応を続けた後２３０℃に昇温し、その後２時間、２３０℃に温度を保ち、水蒸気を徐々に抜いて圧力を２２ｋｇ／ｃｍ^２に保ちながら反応させた。次に、３０分かけて圧力を１０ｋｇ／ｃｍ^２まで下げ、更に１時間反応させて、極限粘度［η］が０．２５ｄｌ／ｇのプレポリマーを得た。これを、１００℃、減圧下で１２時間乾燥し、２ｍｍ以下の大きさまで粉砕した。これを２３０℃、０．１ｍｍＨｇ下にて、１０時間固相重合し、融点が３１７℃、極限粘度［η］が１．１０ｄｌ／ｇ、末端封止率が９０％である白色のポリアミドを得た。
【００６１】
参考例２〜８
ジカルボン酸成分、ジアミン成分および末端封止剤（安息香酸）を、下記の表２に示した割合で用いる以外は、参考例１と同様にして製造することによりポリアミドを得た。得られたポリアミドの極限粘度［η］、末端封止率および融点を併せて下記の表２に示す。
【００６２】
【表２】

【００６３】
実施例１〜３、比較例１〜３および参考例９、１０
参考例１〜８で得られたポリアミドと、下記の表４に示した溶融液晶高分子（ＴＬＣＰ）とを、下記の表４に示した割合で混合し、東洋精機製作所製の二軸押出機「ラボプラストミル２Ｄ２５Ｗ」を使用して、シリンダー温度をポリアミドの融点よりも２０〜４０℃高い温度に設定し、４０ｒｐｍの回転速度で溶融状態で押出すことにより熱可塑性樹脂組成物を得た。この熱可塑性樹脂組成物を、日精樹脂工業製の射出成形機「ＦＳ８０Ｓ１２ＡＳＥ」を用いて、シリンダー温度を樹脂の融点よりも２０〜４０℃高い温度に、金型温度を１５０℃に設定して射出成形した。得られた成形品について評価した結果を下記の表４に示す。なお、下記の表４〜６に記載されている、溶融液晶高分子の略称は下記の表３のとおりである。
【００６４】
【表３】

【００６５】
【表４】

【００６６】
実施例４〜７、比較例４、５および参考例１１
下記の表５に示したポリアミドおよび溶融液晶高分子を、下記の表５に示した割合で混合し、東洋精機製作所製の二軸押出機「ラボプラストミル２Ｄ２５Ｗ」を使用して、シリンダー温度をポリアミドの融点よりも２０〜４０℃高い温度に設定し、４０ｒｐｍの回転速度で溶融状態で押出すことにより熱可塑性組成物を得た。この熱可塑性樹脂組成物を、日精樹脂工業製の射出成形機「ＦＳ８０Ｓ１２ＡＳＥ」を用いて、シリンダー温度を樹脂の融点よりも２０〜４０℃高い温度に、金型温度を１５０℃に設定して射出成形した。得られた成形品について評価した結果を下記の表５に示す。
【００６７】
【表５】

【００６８】
実施例８〜１０および参考例１２、１３
下記の表６に示したポリアミドおよび溶融液晶高分子を、下記の表６に示した割合で混合し、東洋精機製作所製の二軸押出機「ラボプラストミル２Ｄ２５Ｗ」を使用して、シリンダー温度をポリアミドの融点よりも２０〜４０℃高い温度に設定し、４０ｒｐｍの回転速度で溶融状態で押出してペレット化した。こうして得られたペレットと下記の表６に示した充填剤とを、表６に示した割合で混合し、プラスチック工学研究所製の一軸押出機「ＵＴ−４０Ｈ」を用いて、シリンダー温度をポリアミドの融点よりも２０〜４０℃高い温度に設定し、溶融状態で押出すことにより充填剤が配合された熱可塑性樹脂組成物を得た。この熱可塑性樹脂組成物を、日精樹脂工業製の射出成形機「ＦＳ８０Ｓ１２ＡＳＥ」を用いて、シリンダー温度を樹脂の融点よりも２０〜４０℃高い温度に、金型温度を１５０℃に設定して射出成形した。得られた成形品について評価した結果を下記の表６に示す。
【００６９】
【表６】

【００７０】
【発明の効果】
本発明の熱可塑性樹脂組成物は、極めて優れた成形加工性を有すると共に、低吸水性、寸法安定性、耐薬品性、力学強度などに優れており、これらの熱可塑性樹脂組成物から得られるエンジニアリング用途の部品、繊維、フィルム、シート、ボトルなどの種々の形状の成形品は、産業資材、工業材料、家庭用品などの用途に好適に使用することができる。[0001]
[Industrial applications]
The present invention relates to a thermoplastic resin composition comprising a specific semi-aromatic polyamide and a molten liquid crystal polymer, a thermoplastic resin composition obtained by further blending a filler with the thermoplastic resin composition, and a thermoplastic resin comprising the thermoplastic resin composition. The present invention relates to a molded article comprising the composition. The thermoplastic resin composition of the present invention has extremely excellent moldability, low water absorption, dimensional stability, chemical resistance, excellent mechanical strength, and the like, and is obtained from these thermoplastic resin compositions. The molded article can be suitably used for applications such as industrial materials, industrial materials, and household goods.
[0002]
[Prior art]
Conventionally, crystalline polyamides represented by nylon 6, nylon 66, etc. have been widely used as clothing, industrial material fibers, or general-purpose engineering plastics because of their excellent properties and ease of melt molding. On the other hand, problems such as insufficient heat resistance and poor dimensional stability due to water absorption have been pointed out. In particular, in the electric and electronic fields requiring reflow soldering heat resistance with the recent progress of surface mount technology (SMT), or in the parts of the engine room of automobiles where the demand for heat resistance is increasing year by year, the conventional polyamide is used. Is difficult to use, and there is an increasing demand for polyamides having better heat resistance, dimensional stability, mechanical properties, and physicochemical properties.
[0003]
In response to such demands, various types of all-aliphatic polyamides composed of adipic acid and 1,4-butanediamine, and semi-aromatic polyamides containing terephthalic acid and 1,6-hexanediamine as main components have been proposed. Has been put to practical use. However, polyamide comprising adipic acid and 1,4-butanediamine (hereinafter sometimes abbreviated as PA4-6) has a low melt viscosity, and is a semi-aromatic containing terephthalic acid and 1,6-hexanediamine as main components. Although it has good moldability as compared with polyamide, it has a high water absorption, and fluctuations in various physical properties such as dimensional stability during actual use have been regarded as a problem.
[0004]
On the other hand, a polyamide composed of terephthalic acid and 1,6-hexanediamine (hereinafter sometimes abbreviated as PA6-T) has a melting point around 370 ° C., which is higher than the decomposition temperature of the polymer. Difficult and not practical. Therefore, in practice, 30 to 40 mol% of a dicarboxylic acid component such as adipic acid or isophthalic acid or an aliphatic polyamide such as nylon 6 is copolymerized to reach a practically usable temperature range, that is, about 280 to 320 ° C. It is used in a composition with a low melting point. Although copolymerization of such a large amount of the third component (or the fourth component in some cases) is certainly effective in lowering the melting point of the polymer, it is accompanied by a decrease in the crystallization speed and the ultimate crystallinity. As a result, not only physical properties such as rigidity at high temperatures, chemical resistance and dimensional stability are reduced, but also productivity is reduced due to extension of the molding cycle. Also, the fluctuation of various properties such as dimensional stability due to water absorption has been improved to some extent compared to conventional aliphatic polyamides by the introduction of aromatic groups, but has reached the level of substantial problem solving. Not.
[0005]
As a method for improving the dimensional stability, heat resistance, moldability, and mechanical strength of a polyamide, a method of blending a molten liquid crystal polymer (hereinafter may be abbreviated as “TLCP”) with the polyamide is known. For example, Japanese Patent Application Laid-Open No. 2-199167 discloses that 1 to 5 parts by weight of a liquid crystal polymer is mixed with 100 parts by weight of a polyamide comprising terephthalic acid and isophthalic acid and 1,6-hexanediamine and having a melting point of 330 ° C. A thermoplastic resin composition is described. JP-A-3-17156 discloses that 100 parts by weight of a polyamide composed of terephthalic acid, isophthalic acid and adipic acid and 1,6-hexanediamine and having a melting point of 312 ° C. is mixed with a liquid crystal polymer of 0.2 to 67 parts by weight. A thermoplastic resin composition blended by weight is described.
[0006]
[Problems to be solved by the invention]
According to the study of the present inventors, the PA6-T-based polyamide obtained by additional testing of the method described in the above-mentioned JP-A-2-199167 or JP-A-3-17156 has a high melt liquid crystal content. The thermoplastic resin composition containing a predetermined amount of molecules has a problem that bubbles are easily generated at the time of molding, and further, in the dimensional stability and chemical resistance of a molded article obtained from the resin composition, It is hard to say that it has enough performance for the severe demands of the market. Further, the above publication discloses a specific disclosure that by using a diamine having 7 or more carbon atoms as a diamine component, more excellent performance is exhibited as compared with a case where 1,6-hexanediamine is used. Absent.
[0007]
An object of the present invention is to provide a thermoplastic resin composition having significantly improved moldability, low water absorption, excellent dimensional stability, excellent chemical resistance, and excellent mechanical strength. . Still another object of the present invention is to provide a molded article comprising the above-mentioned thermoplastic resin composition having excellent properties.
[0008]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a semi-aromatic polyamide containing terephthalic acid units and 1,9-nonanediamine units as main components.ToOnly by blending a specific amount of a molten liquid crystal polymer with a semi-aromatic polyamide obtained by copolymerizing a specific amount of 2-methyl-1,8-octanediamine unit, extremely excellent moldability and low water absorption and dimensions are obtained. The inventors have found that a thermoplastic resin composition having excellent stability, chemical resistance, and the like can be obtained, and have completed the present invention.
[0009]
That is, the present inventionIs60 to 100 mol% of the carboxylic acid units are composed of terephthalic acid units, 60 to 100 mol% of the diamine units are composed of 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units, and A polyamide having a molar ratio of nonanediamine units to 2-methyl-1,8-octanediamine units of from 60:40 to 99: 1, and an intrinsic viscosity [η] of 0.4 measured in concentrated sulfuric acid at 30 ° C. ~ 3.0 dl / g polyamide (AA) a thermoplastic resin composition comprising 0.1 to 200 parts by weight of a molten liquid crystal polymer (B) in 100 parts by weight. Further, the present invention is a thermoplastic resin composition obtained by mixing 1 to 200 parts by weight of a filler with 100 parts by weight of the above thermoplastic resin composition. Further, the present invention is a molded article comprising the above-mentioned thermoplastic resin composition.
[0010]
Hereinafter, the present invention will be described specifically.
The polyamide used in the present invention substantially consists of dicarboxylic acid units and diamine units. The dicarboxylic acid unit needs to contain a terephthalic acid unit in an amount of at least 60 mol%, preferably at least 75 mol%, more preferably at least 90 mol%. When the content of the terephthalic acid unit is less than 60 mol%, various properties such as low water absorption and chemical resistance of the obtained thermoplastic resin composition are undesirably reduced.
[0011]
Other dicarboxylic acid units other than the terephthalic acid unit include malonic acid, dimethylmalonic acid, succinic acid, 3,3-diethylsuccinic acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, and 2-methyladipic acid Aliphatic dicarboxylic acids such as trimethyladipic acid, pimelic acid, azelaic acid, sebacic acid and suberic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; isophthalic acid; 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, 4,4 '-Oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4, '- dicarboxylic acid, there may be mentioned units derived from aromatic dicarboxylic acids such as 4,4'-biphenyl dicarboxylic acid, it is possible to include one or more of these. From the viewpoint of heat resistance and the like, it is preferable to include an aromatic dicarboxylic acid unit among the above dicarboxylic acid units. Further, a unit derived from a polycarboxylic acid having three or more functional groups such as trimellitic acid, trimesic acid, and pyromellitic acid can be included in a range where melt molding is possible.
[0012]
Also,As diamine unitIs1,9-nonanediamine unitAnd 2-methyl-1,8-octanediamine unitTo 60~ 100Mole% IncludedNeed to haveYou.
And, the molar ratio of 1,9-nonanediamine unit to 2-methyl-1,8-octanediamine unit is 60:40 to 99: 1, preferably 70:30 to 99: 1, and 80:20. ９８98: 2 is more preferable. By containing 1,9-nonanediamine unit and 2-methyl-1,8-octanediamine unit as the diamine unit in the above ratio, the moldability, low water absorption, heat resistance, chemical resistance, and mechanical properties are all reduced. Thus, an excellent thermoplastic resin composition can be obtained.
[0013]
1,9-nonanediamine unit,2-methyl-1,8-octanediamine unitOther diamine units other than the above include, for example, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine , 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6- Hexanediamine, 5Aliphatic diamines such as -methyl-1,9-nonanediamine; alicyclic diamines such as cyclohexanediamine, methylcyclohexanediamine and isophoronediamine; p-phenylenediamine, m-phenylenediamine, xylylenediamine, 4,4'-diamino Examples include units derived from aromatic diamines such as diphenylmethane, 4,4'-diaminodiphenylsulfone, and 4,4'-diaminodiphenylether, and one or more of these units may be included.You.
[0014]
Polyamide used in the present invention (A) Is, That10% or more of the terminal groups of the molecular chain are blocked by a terminal blocking agentthingIs preferred, and 40% or more of the terminal groups are sealed.thingIs more preferable, and 60% or more of the terminal groups are sealed.thingIs more preferred. By sealing the terminal group of the polyamide, a thermoplastic resin composition having more excellent hot water resistance and a small change in viscosity during melt molding can be obtained.
[0015]
In determining the terminal capping ratio, the number of carboxyl group terminals, amino group terminals, and the number of terminals capped by the terminal capping agent present in the polyamide are measured, and the terminal capping is performed by the following formula (1). Rate can be determined. The number of each terminal group is¹It is preferable from the viewpoints of accuracy and simplicity that it be determined from the integrated value of the characteristic signal corresponding to each terminal group by H-NMR. When the characteristic signal of the terminal capped by the terminal blocking agent cannot be identified, the intrinsic viscosity [η] of the polyamide is measured,
Mn = 21900 [η] -7900 (Mn represents a number average molecular weight)
Total number of molecular chain terminal groups (eq / g) = 2 / Mn
Is used to calculate the total number of molecular chain terminal groups. Further, the number of carboxyl group terminals of the polyamide (eq / g) [titrate the benzyl alcohol solution of polyamide with 0.1 N sodium hydroxide] and the number of amino group terminals (eq / g) of the polyamide [ Titration with 0.1N hydrochloric acid], and the end capping ratio can be determined by the following equation (1).
[0016]
Terminal blocking rate (%) = [(AB) −A] × 100 (1)
[Wherein A represents the total number of molecular chain terminal groups (this is usually equal to twice the number of polyamide molecules), and B represents the total number of carboxyl group terminals and amino group terminals]
[0017]
The terminal capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the amino group or carboxyl group at the polyamide terminus. Acids or monoamines are preferred, and monocarboxylic acids are more preferred from the viewpoint of easy handling. In addition, acid anhydrides such as phthalic anhydride, monoisocyanates, monoacid halides, monoesters, and monoalcohols can also be used.
[0018]
The monocarboxylic acid used as the terminal capping agent is not particularly limited as long as it has reactivity with an amino group.For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, Aliphatic monocarboxylic acids such as lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutylic acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α-naphthalenecarboxylic acid Examples thereof include acids, β-naphthalene carboxylic acid, methyl naphthalene carboxylic acid, aromatic monocarboxylic acids such as phenylacetic acid, and arbitrary mixtures thereof. Among them, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, from the viewpoints of reactivity, sealed terminal stability, and price. And benzoic acid are particularly preferred.
[0019]
When the terminal group of the polyamide is sealed with a monocarboxylic acid, the number of moles of the diamine component to the dicarboxylic acid component is slightly increased in the production of the polyamide so that both ends of the polyamide are amino groups, An acid may be added as a terminal blocking agent.
[0020]
The amino terminal of the polyamide is blocked with these monocarboxylic acids to form a blocked terminal represented by the following general formula (I).
[0021]
Embedded image

(In the formula, R is a residue obtained by removing the carboxyl group from the above monocarboxylic acid, and is preferably an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.)
[0022]
The monoamine used as an end capping agent is not particularly limited as long as it has reactivity with a carboxyl group.For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, Aliphatic monoamines such as stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; cycloaliphatic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine and naphthylamine, or any of these Mixtures can be mentioned. Of these, butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline are particularly preferred from the viewpoints of reactivity, boiling point, stability of the sealed terminal, and price.
[0023]
When the end groups of the polyamide are sealed with a monoamine, the number of moles of the diamine component with respect to the dicarboxylic acid component is slightly reduced in the production of the polyamide so that both ends of the polyamide are carboxyl groups, and the monoamine is end-sealed. It is good to add it as a blocking agent.
[0024]
The carboxyl group terminal of the polyamide is blocked with these monoamines to form a blocked terminal represented by the following general formula (II).
[0025]
Embedded image

(Where R¹Is a residue obtained by removing an amino group from the above monoamine, and is preferably an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. R²Is a hydrogen atom or a residue obtained by removing the amino group from the above monoamine, and is preferably a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. )
[0026]
The amount of the end-capping agent used when producing the polyamide varies depending on the reactivity of the end-capping agent used, the boiling point, the reaction apparatus, the reaction conditions, and the like. It is preferably used in the range of 0.1 to 15 mol%.
[0027]
The polyamide used in the present invention can be produced by a method conventionally known as a method for producing a polyamide, such as a melt polymerization method, a solution polymerization method, or a polymerization method using a reactive extruder. According to the study of the present inventors, a catalyst and, if necessary, an end capping agent are first added to a diamine and a dicarboxylic acid at a time, and a nylon salt is produced. A polyamide can be easily obtained by forming a prepolymer having an intrinsic viscosity [η] of 0.10 to 0.60 dl / g in sulfuric acid at 30 ° C. and further performing solid phase polymerization or performing polymerization using a melt extruder. be able to. When the intrinsic viscosity [η] of the prepolymer is in the range of 0.10 to 0.60 dl / g, the deviation of the molar balance between the carboxyl group and the amino group and the decrease in the polymerization rate in the post-polymerization stage are small, and the molecular weight is further reduced. A polyamide having a small distribution and excellent in various properties and moldability can be obtained. When the final stage of the polymerization is carried out by solid-phase polymerization, it is preferable to carry out under reduced pressure or under an inert gas flow.If the polymerization temperature is in the range of 180 to 280 ° C., the polymerization rate is large and the productivity is excellent. It is preferable because coloring and gelation can be effectively suppressed. When the final stage of the polymerization is carried out by a melt extruder, it is preferable that the polymerization temperature is 370 ° C. or lower, since the polyamide is hardly decomposed and a polyamide without deterioration is obtained.
[0028]
Catalysts that can be used in the production of polyamide include phosphoric acid, phosphorous acid, hypophosphorous acid, or ammonium salts thereof, and metal salts thereof (potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, etc.). , Manganese, tin, tungsten, germanium, titanium, antimony and other metal salts) and their esters (ethyl ester, isopropyl ester, butyl ester, hexyl ester, isodecyl ester, octadecyl ester, decyl ester, stearyl ester, phenyl ester ).
[0029]
The polyamide used in the present invention has an intrinsic viscosity [η] measured in concentrated sulfuric acid at 30 ° C. in the range of 0.4 to 3.0 dl / g, and in the range of 0.6 to 2.0 dl / g. Are preferable, and those in the range of 0.8 to 1.6 dl / g are more preferable. When the intrinsic viscosity [η] of the polyamide is within the above range, a thermoplastic resin composition having not only excellent moldability but also excellent physical properties such as mechanical properties and heat resistance properties can be obtained.
[0030]
The polyamide used in the present invention has an intrinsic viscosity [η] in the range of 0.4 to 3.0 dl / g, and has an intrinsic viscosity [η] and a shear rate of 1000 s.^-1A relationship represented by the following equation (2) is established with the melt viscosity (MV) measured in the above.
logMV = 1.9 [η] + A (2)
(Here, A is a number that changes with temperature.)
[0031]
In the case of the preferred polyamide used in the present invention, the A value at 340 ° C is 0.6 to 1.0, and the difference between the A value at 330 ° C and the A value at 350 ° C is 0.1 to 0. 6. On the other hand, in the case of a conventional PA6-T-based polyamide, the coefficient of intrinsic viscosity [η] is almost the same as the polyamide used in the present invention, but the A value at 340 ° C. is 1.3 to 1.7, The difference between the A value at 330 ° C. and the A value at 350 ° C. is 0.7 to 1.1. As described above, at a preferable molding temperature of 330 to 350 ° C., the polyamide used in the present invention has a lower melt viscosity even at the same intrinsic viscosity [η] as compared with the conventional PA6-T-based polyamide. The change in melt viscosity due to the change in temperature is also small. Furthermore, the polyamide used in the present invention also has the property that the change in melt viscosity during the residence time during molding is small, and the moldability is significantly improved as compared with the conventional PA6-T-based polyamide. ing.
[0032]
In the thermoplastic resin composition of the present invention, it is necessary to mix a specific amount of a molten liquid crystal polymer with the above polyamide. By blending a specific amount of the molten liquid crystal polymer, a thermoplastic resin composition excellent in mechanical strength, low water absorption, chemical resistance and the like can be obtained. The compounding ratio of the molten liquid crystal polymer should be 0.1 to 200 parts by weight, preferably 0.5 to 150 parts by weight, and more preferably 1 to 100 parts by weight with respect to 100 parts by weight of the polyamide. Is more preferred.
[0033]
The molten liquid crystal polymer used in the present invention has a property of forming a liquid crystal in the molten phase (ie, exhibits optical anisotropy), and has an intrinsic viscosity [η] measured in pentafluorophenol at 60 ° C. It is preferably 0.1 to 5 dl / g. Confirmation of such optical anisotropy in the molten phase, using a polarizing microscope equipped with a heating device, under orthogonal Nicols, a thin slice of the sample, preferably a thin slice of about 5 to 20 μm sandwiched between cover glasses, It can be performed by observing at a constant heating rate and seeing that light is transmitted at a certain temperature or higher. During observation, the transmission of polarized light can be observed more reliably by applying a slight pressure to the sample sandwiched between the cover glasses at a high temperature, or by sliding the cover glass. The temperature at which polarized light starts to pass is the transition temperature to the optically anisotropic molten phase, and the transition temperature of the molten liquid crystal polymer used in the present invention is 400 ° C. or less from the viewpoint of ease of melt molding. Preferably, the temperature is 350 ° C. or lower.
[0034]
The structure of the molten liquid crystal polymer used in the present invention is not particularly limited as long as it satisfies the above conditions. As a typical example, a polyester substantially consisting of an aromatic hydroxycarboxylic acid unit; Polyester consisting of hydroxycarboxylic acid units, aromatic dicarboxylic acid units and aromatic diol units; polyester consisting essentially of aromatic hydroxycarboxylic acid units, aromatic dicarboxylic acid units and aliphatic diol units; substantially aromatic hydroxycarboxylic acid Polyester amide consisting essentially of an acid unit and an aromatic aminocarboxylic acid unit; polyester amide consisting essentially of an aromatic hydroxycarboxylic acid unit, an aromatic dicarboxylic acid unit and an aromatic diamine unit; substantially an aromatic hydroxycarboxylic acid unit, aromatic Aromatic aminocarboxylic acid unit, aromatic Polyester amide composed of a dicarboxylic acid unit and an aromatic diol unit; polyester amide substantially composed of an aromatic hydroxy carboxylic acid unit, an aromatic amino carboxylic acid unit, an aromatic dicarboxylic acid unit, and an aliphatic diol unit. .
[0035]
The aromatic hydroxycarboxylic acid unit constituting the molten liquid crystal polymer is derived from, for example, p-hydroxybenzoic acid, m-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, 7-hydroxy-2-naphthoic acid, and the like. Units can be listed. Examples of the aromatic aminocarboxylic acid unit include units derived from p-aminobenzoic acid, m-aminobenzoic acid, 6-amino-2-naphthoic acid, 7-amino-2-naphthoic acid, and the like. Examples of the aromatic dicarboxylic acid unit include terephthalic acid, isophthalic acid, chlorobenzoic acid, 4,4′-biphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, and 4,4′-oxydibenzoic acid Examples include units derived from an acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, and the like. As the aromatic diol unit, hydroquinone, resorcinol, methylhydroquinone, chlorohydroquinone, phenylhydroquinone, 4,4′-dihydroxybiphenyl, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 4,4′-dihydroxydiphenyl ether, Examples include units derived from 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenylsulfone, and the like. Examples of the aliphatic diol unit include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, Examples include units derived from 9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, and the like. Examples of the aromatic diamine unit include units derived from p-phenylenediamine, m-phenylenediamine, 4,4'-diaminobiphenyl, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, and the like.
[0036]
Preferred examples of the molten liquid crystal polymer used in the present invention include, for example, a polyester comprising a p-hydroxybenzoic acid unit and a 6-hydroxy-2-naphthoic acid unit; a p-hydroxybenzoic acid unit, 4,4′-dihydroxy Polyester consisting of biphenyl units and terephthalic acid units; polyester consisting of p-hydroxybenzoic acid units, ethylene glycol units and terephthalic acid units; p-hydroxybenzoic acid units, 6-hydroxy-2-naphthoic acid units and p-aminobenzoic acid Examples thereof include a polyesteramide composed of units.
[0037]
The filler can be further blended in an amount of 1 to 200 parts by weight based on 100 parts by weight of the thermoplastic resin composition. Mixing the filler in such a ratio is preferable because a thermoplastic resin composition having more improved properties such as moldability, mechanical properties, and heat distortion temperature is obtained. The compounding ratio of the filler is more preferably from 1 to 150 parts by weight, and even more preferably from 2 to 100 parts by weight, based on 100 parts by weight of the polyamide.
[0038]
As the filler, conventionally known fillers having various forms such as powder, fiber, cloth and the like can be used.
[0039]
Powdered fillers include silica, silica alumina, alumina, titanium oxide, zinc oxide, boron nitride, talc, mica, potassium titanate, calcium silicate, magnesium sulfate, aluminum borate, asbestos, glass beads, carbon black, Examples include graphite, molybdenum disulfide, and polytetrafluoroethylene. Usually, as such a powdery filler, one having an average particle size in the range of 0.1 μm to 200 μm is preferably used, and one having an average particle size in the range of 1 μm to 100 μm is more preferably used. The use of these powdery fillers improves the dimensional stability, mechanical properties, heat resistance properties, physicochemical properties, sliding properties, etc. of the molded article obtained from the thermoplastic resin composition.
[0040]
As the fibrous filler, polyparaphenylene terephthalamide fiber, polymetaphenylene terephthalamide fiber, polyparaphenylene isophthalamide fiber, polymetaphenylene isophthalamide fiber, obtained from a condensate of diaminodiphenyl ether and terephthalic acid or isophthalic acid Organic fibrous fillers such as wholly aromatic polyamide fibers such as fibers and wholly aromatic liquid crystal polyester fibers; and inorganic fibrous fillers such as glass fibers, carbon fibers or boron fibers. The use of such a fibrous filler is preferable because not only the mechanical strength of a molded article obtained from the thermoplastic resin composition is improved, but also the dimensional stability, low water absorption and the like are improved. Usually, as such a fibrous filler, one having an average length in the range of 0.05 to 50 mm is preferably used. Furthermore, it is more preferable to use those having an average length in the range of 1 to 10 mm from the viewpoint that the moldability is good and the sliding properties, heat resistance, and mechanical properties of the obtained molded article are further improved. These fibrous fillers may be subjected to secondary processing such as cloth.
[0041]
These fillers can be used alone or in combination of two or more. In particular, by using the fibrous filler and the powdery filler in combination, it is possible to obtain a thermoplastic resin composition having more excellent moldability, surface beauty, mechanical properties, and heat resistance. It is preferable because it is possible. Further, as these fillers, those subjected to a surface treatment with a silane coupling agent, a titanium coupling agent or the like can also be used. It is preferable to use a filler whose surface is treated with these coupling agents, since the resulting molded article has excellent mechanical properties. Among the silane coupling agents, it is more preferable to use an aminosilane-based coupling agent because the obtained molded article has particularly excellent mechanical properties.
[0042]
In addition, if necessary, a stabilizer such as a copper compound; a coloring agent; an ultraviolet absorber; a light stabilizer; an antioxidant such as a hindered phenol-based, hindered amine-based, phosphorus-based, or thio-based; an antistatic agent; Flame retardants such as polymers, antimony oxide, metal hydroxides; crystal nucleating agents; plasticizers; lubricants, anti-slip agents, anti-blocking agents, anti-fogging agents, pigments, dyes, polyamides such as natural oils, synthetic oils and waxes Can be added during or after the polycondensation reaction.
[0043]
The thermoplastic resin composition of the present invention can be produced by mixing the above polyamide and the molten liquid crystal polymer and, if necessary, the above fillers and additives by a desired method. For example, after pre-mixing using a vertical or horizontal mixer as commonly used for mixing resin materials, using a kneading device such as a single-screw or twin-screw extruder, kneader, mixing roll, Banbury mixer, etc. By melt-kneading under heating, the thermoplastic resin composition of the present invention is produced.
[0044]
Using the resin composition produced as described above, a molded article having a desired shape can be produced by a usual melt molding method, for example, a compression molding method, an injection molding method, an extrusion molding method, or the like.
[0045]
For example, the thermoplastic resin composition of the present invention is melted in a cylinder of an injection molding machine having a cylinder temperature adjusted to 280 to 350 ° C., and is introduced (injected) into a mold having a predetermined shape. Molded articles can be manufactured. Further, a fiber can be produced by melting the thermoplastic resin composition in an extruder adjusted to the above-mentioned cylinder temperature and spinning out from a die nozzle. Further, a film can be produced by melting the thermoplastic resin composition in an extruder adjusted to the cylinder temperature and extruding the resin from a T-die. Further, molded articles such as films and bottles can be obtained by inflation molding, blow molding and the like.
[0046]
The molded article as described above can be used in a state where the surface is further coated with a paint, a metal layer, or another kind of polymer.
[0047]
Examples of molded articles made of the thermoplastic resin composition of the present invention include electric tools, general industrial parts, gears, mechanical parts such as cams, connectors, switches, relays, MIDs, printed wiring boards, housings for electronic parts, and the like. And molded articles of various forms such as electronic parts, films, sheets, and fibers. In particular, it can be suitably used for molded articles for automobiles, for example, interior and exterior parts of automobiles, parts in an engine room of automobiles, and electrical parts of automobiles.
[0048]
【Example】
Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. In the following examples, the terminal sealing rate, intrinsic viscosity and melting point of polyamide; melt viscosity of the thermoplastic resin composition; tensile strength, water absorption, linear expansion coefficient, alcohol resistance and hot water resistance of the molded product are as follows: It was measured or evaluated according to the method.
[0049]
Terminal sealing rate:
¹Using H-NMR (500 MHz, measured in deuterated trifluoroacetic acid at 50 ° C.), the number of carboxyl group ends, amino group ends, and sealed ends was measured from the integrated value of the characteristic signal for each terminal group. The terminal blocking ratio was determined from the above formula (1). The chemical shift values of typical signals used for the measurement are shown below.
[0050]
[Table 1]

[0051]
Intrinsic viscosity [η]:
The intrinsic viscosity (ηinh) of a sample having a concentration of 0.05, 0.1, 0.2, 0.4 g / dl was measured in concentrated sulfuric acid at 30 ° C. The intrinsic viscosity [η] was used.
ηinh = [ln (t₁/ T₀)] / C
[Wherein, ηinh is the intrinsic viscosity (dl / g), t₀Is the flow time (second) of the solvent, t₁Represents the flow time (second) of the sample solution, and c represents the concentration of the sample in the solution (g / dl). ]
[0052]
Melting point:
Using a differential scanning calorimeter (“DSC30” manufactured by Mettler), the sample was heated at a rate of 100 ° C./min to completely melt, and then cooled to 50 ° C. at a rate of 10 ° C./min. The temperature at the position of the endothermic peak appearing when the temperature was raised again at a rate of 10 ° C./min was measured and defined as the melting point.
[0053]
Melt fluidity:
Using KAYNESS “Capillary Rheometer, GALAXYV MODEL8052” (die diameter 1 mm, L / D = 10), shearing speed 1000 s at 340 ° C.^-1The melt viscosity (poise) was measured as an index of moldability.
[0054]
Water absorption:
An injection molded product of 80 × 80 × 3 mm was immersed in water at 23 ° C. for 24 hours. The water absorption (%) was determined from the weight change of the molded article before and after immersion.
[0055]
Tensile strength:
Using a JIS No. 1 dumbbell-type injection molded piece, the measurement was performed according to JIS K7113.
[0056]
Linear expansion coefficient:
A test piece of 3 × 3 × 3 mm was prepared from an injection molded product of 80 × 80 × 3 mm, and when heated at a rate of 10 ° C./min, in the machine axis direction (MD direction) in a temperature range of 50 to 70 ° C. The dimensional change was measured using a thermomechanical analysis (TMA) device (“TMA40” manufactured by METTLER COMPANY), and the coefficient of linear expansion was determined by the following equation (3).
[0057]
Linear expansion coefficient (1 / ° C) = (L₁-L₂) / [(T₁−T₂) × L₀] (3)
(Where L₀Is the initial sample length (mm), L₁Is the sample length (mm) at 70 ° C., L₂Is the sample length (mm) at 50 ° C., T₁Is 70 (° C), T₂Indicates 50 (° C.). )
[0058]
Alcohol resistance:
The JIS No. 1 dumbbell-shaped injection molded piece was immersed in methanol at 23 ° C. for one week. The tensile strength of the molded article before and after immersion was measured, and the retention rate (%) of the tensile strength was determined.
[0059]
Hot water:
The JIS No. 1 dumbbell-type injection molded piece was subjected to steam treatment in a pressure-resistant autoclave (120 ° C., 2 atm for 120 hours), and the sample was vacuum-dried at 120 ° C. for 120 hours. The tensile strength of the molded article before and after the treatment was measured, and the retention rate (%) of the tensile strength was determined.
[0060]
Reference Example 1
3256.2 g (19.60 mol) of terephthalic acid, 3165.8 g (20.0 mol) of 1,9-nonanediamine, 97.7 g (0.80 mol) of benzoic acid, sodium hypophosphite monohydrate 5 g (0.1% by weight based on the raw material) and 2.2 liters of distilled water were put into an autoclave having an internal volume of 20 liters, and the atmosphere was replaced with nitrogen. The mixture was stirred at 100 ° C for 30 minutes, and the internal temperature was raised to 210 ° C over 2 hours. At this time, the autoclave is 22 kg / cm²Pressurized to After continuing the reaction for 1 hour, the temperature was raised to 230 ° C., and then maintained at 230 ° C. for 2 hours.²The reaction was carried out while keeping Next, the pressure is increased to 10 kg / cm over 30 minutes.²Then, the mixture was further reacted for 1 hour to obtain a prepolymer having an intrinsic viscosity [η] of 0.25 dl / g. This was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a size of 2 mm or less. This was subjected to solid phase polymerization at 230 ° C. and 0.1 mmHg for 10 hours to obtain a white polyamide having a melting point of 317 ° C., an intrinsic viscosity [η] of 1.10 dl / g, and a terminal blocking rate of 90%. Was.
[0061]
Reference Examples 2 to 8
A polyamide was obtained in the same manner as in Reference Example 1, except that the dicarboxylic acid component, the diamine component, and the terminal blocking agent (benzoic acid) were used in the proportions shown in Table 2 below. The intrinsic viscosity [η], terminal capping rate and melting point of the obtained polyamide are shown in Table 2 below.
[0062]
[Table 2]

[0063]
Example 13, Comparative Examples 1 to 3And Reference Examples 9 and 10
The polyamides obtained in Reference Examples 1 to 8 and the molten liquid crystal polymer (TLCP) shown in Table 4 below were mixed at the ratio shown in Table 4 below, and a twin screw extruder manufactured by Toyo Seiki Seisaku-sho, Ltd. The cylinder temperature was set to a temperature higher by 20 to 40 ° C. than the melting point of the polyamide by using “Laboplast Mill 2D25W”, and a thermoplastic resin composition was obtained by extruding in a molten state at a rotation speed of 40 rpm. The thermoplastic resin composition was injected by using an injection molding machine “FS80S12ASE” manufactured by Nissei Plastics Industry Co., Ltd. with the cylinder temperature set to 20 to 40 ° C. higher than the melting point of the resin and the mold temperature set to 150 ° C. Molded. Table 4 below shows the results of the evaluation of the obtained molded products. The abbreviations of the molten liquid crystal polymers described in Tables 4 to 6 below are shown in Table 3 below.Is.
[0064]
[Table 3]

[0065]
[Table 4]

[0066]
Example4~7Comparative Examples 4 and 5And Reference Example 11
The polyamide and the molten liquid crystal polymer shown in Table 5 below were mixed at a ratio shown in Table 5 below, and the cylinder temperature was adjusted using a twin screw extruder “Laboplast Mill 2D25W” manufactured by Toyo Seiki Seisaku-sho, Ltd. The thermoplastic composition was obtained by setting the temperature to 20 to 40 ° C. higher than the melting point of the polyamide and extruding in a molten state at a rotation speed of 40 rpm. The thermoplastic resin composition was injected by using an injection molding machine “FS80S12ASE” manufactured by Nissei Plastics Industry Co., Ltd. with the cylinder temperature set to 20 to 40 ° C. higher than the melting point of the resin and the mold temperature set to 150 ° C. Molded. Table 5 below shows the results of the evaluation of the obtained molded product.
[0067]
[Table 5]

[0068]
Example8~ 10 and Reference Examples 12 and 13
The polyamide and the molten liquid crystal polymer shown in Table 6 below were mixed at the ratio shown in Table 6 below, and the cylinder temperature was adjusted using a twin screw extruder “Laboplast Mill 2D25W” manufactured by Toyo Seiki Seisaku-sho, Ltd. The temperature was set to 20 to 40 ° C. higher than the melting point of the polyamide, and the mixture was extruded in a molten state at a rotation speed of 40 rpm to be pelletized. The pellets thus obtained and the fillers shown in Table 6 below were mixed at the ratio shown in Table 6, and the cylinder temperature was adjusted to polyamide using a single screw extruder “UT-40H” manufactured by Plastics Engineering Laboratory. Was set at a temperature higher by 20 to 40 ° C. than the melting point of, and extruded in a molten state to obtain a thermoplastic resin composition containing a filler. The thermoplastic resin composition was injected by using an injection molding machine “FS80S12ASE” manufactured by Nissei Plastics Industry Co., Ltd. with the cylinder temperature set to 20 to 40 ° C. higher than the melting point of the resin and the mold temperature set to 150 ° C. Molded. Table 6 below shows the results of the evaluation of the obtained molded product.
[0069]
[Table 6]

[0070]
【The invention's effect】
The thermoplastic resin composition of the present invention has extremely excellent moldability, low water absorption, dimensional stability, chemical resistance, excellent mechanical strength, and the like, and is obtained from these thermoplastic resin compositions. Molded articles of various shapes such as parts for engineering use, fibers, films, sheets and bottles can be suitably used for applications such as industrial materials, industrial materials and household goods.

Claims (3)

60-100 mol% of dicarboxylic acid units consist of terephthalic acid units, 60-100 mol% of diamine units consist of 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units, and 1,9 A polyamide having a molar ratio of nonanediamine units to 2-methyl-1,8-octanediamine units of from 60:40 to 99: 1, and an intrinsic viscosity [η] of 0.4 measured in concentrated sulfuric acid at 30 ° C. A thermoplastic resin composition obtained by blending 0.1 to 200 parts by weight of a molten liquid crystal polymer (B) with 100 parts by weight of a polyamide ( A ) having a viscosity of up to 3.0 dl / g. A thermoplastic resin composition comprising 100 parts by weight of the thermoplastic resin composition according to claim 1 and 1 to 200 parts by weight of a filler. Molded article comprising a thermoplastic resin composition according to claim 1 or 2.