JP4323202B2 - Process for producing thermoplastic resin composition pellets or injection molded products - Google Patents

Description

【００２０】
具体的な(A1)ポリフェニレンエーテルとしては、ポリ（２、６−ジメチル−１、４−フェニレン）エ−テル、ポリ（２、６−ジエチル−１、４−フェニレン）エ−テル、ポリ（２、６−ジプロピル−１、４−フェニレン）エ−テル、ポリ（２−メチル、６−エチル−１、４−フェニレン）エ−テル、ポリ（２−メチル、６−プロピル−１、４−フェニレン）エ−テルなどが挙げられる。中でも、ポリ（２、６−ジメチル−１、４−フェニレン）エ−テルが好ましい。好ましい(A1)ポリフェニレンエーテルは、クロロホルム中、温度３０℃で測定したの固有粘度が０．３〜０．５ｄｌ／ｇのものである。固有粘度が０．３ｄｌ／ｇ未満では、最終的に得られる樹脂組成物の耐衝撃性が不足し、０．５ｄｌ／ｇを超えると最終的に得られる樹脂組成物の成形加工性が悪化し、成形品の外観も悪くなり、いずれも好ましくない。
【００２１】
本発明において(A2)のブロック共重合体の水素添加物とは、ビニル芳香族化合物重合体ブロックＡと共役ジエン系化合物重合体ブロックＢとのブロック共重合弾性体であって、水素添加されてブロックＢの脂肪族不飽和基が減少した水素添加ブロック共重合体を意味する。ブロックＡおよびブロックＢの配列は、線状構造、分岐構造（ラジカルテレブロック）などいずれの構造であってもよい。また、これらの構造のうちで、一部にビニル芳香族化合物と共役ジエン系化合物とのランダム共重合部分に由来するランダム鎖を含んでいてもよい。これら構造のうちでは、線状構造のものが好ましく、Ａ−Ｂ−Ａ型のトリブロック構造のものが特に好ましく、ジブロック構造のものを含んでいてもよい。
【００２２】
(A2)ブロック共重合体の水素添加物のビニル芳香族化合物は、好ましくはスチレン、α−メチルスチレン、パラメチルスチレン、ビニルトルエン、ビニルキシレンなどであり、更に好ましくは、スチレンである。共役ジエン系化合物は、好ましくは１，３−ブタジエン、２−メチル−１，３−ブタジエンである。(A2)ブロック共重合体の水素添加物におけるビニル芳香族化合物に由来する繰り返し単位の占める割合は、１０〜７０重量％の範囲が好ましく、１０〜４０重量％の範囲がより好ましい。ブロック共重合体における脂肪族鎖部分のうち、共役ジエン系化合物に由来し、水素添加されずに残存している不飽和結合の割合は、２０％以下が好ましく、１０％以下がより好ましい。また、ビニル芳香族化合物に由来する芳香族性不飽和結合は、その約２５％以下が水素添加されていてもよい。
【００２３】
これらの(A2)水素添加ブロック共重合体の数平均分子量は、１８０，０００以下のものが好ましく、１２０，０００以下のものがより好ましい。分子量が１８０，０００を越えると、樹脂組成物に分散する不連続相粒子が特殊な構造とならず、耐衝撃性と寸法安定性に劣り、成形加工性も劣るので好ましくない。
【００２４】
本発明において(A3)不飽和酸無水物および／または不飽和酸としては、無水マレイン酸、無水イタコン酸、クロロ無水マレイン酸、無水シトラコン酸、ブテニル無水コハク酸、テトラヒドロ無水フタル酸、およびこれらの酸が挙げられる。中でも特に好ましいのは、無水マレイン酸および／またはマレイン酸である。これらの不飽和酸無水物および／または不飽和酸は、一種でも二種以上であってもよい。
【００２５】
本発明において(A4)ラジカル発生剤としては、有機過酸化物、アゾ化合物などを挙げることができる。有機過酸化物の具体例として、（イ）ハイドロパーオキサイド類；例えばｔ−ブチル−ハイドロパーオキサイド、キュメン−ハイドロパーオキサイド、２，５−ジメチルヘキサン−２，５−ジハイドロパーオキサイド、１，１，３，３−テトラメチルブチル−ハイドロパーオキサイド、ｐ−メンタン−ハイドロパーオキサイド、ジイソプロピルベンゼンハイドロパーオキサイドなど、（ロ）ジ−アルキルパーオキサイド類、例えば２，５−ジメチル−２，５−ジ（ｔ−ブチルパーオキシ）ヘキシン−３、ジ−ｔ−ブチル−パーオキサイド、ｔ−ブチル−キュミル−パーオキサイド、２，５−ジメチル−２，５−ジ（ｔ−ブチルパーオキシ）ヘキサン、ジ−キュミルパーオキサイドなど、（ハ）パーオキシケタール類、例えば２，２−ビス−ｔ−ブチルパーオキシ−ブタン、２，２−ビス−ｔ−ブチル−パーオキシ−オクタン、１，１−ビス−ｔ−ブチルパーオキシ−シクロヘキサン、１，１−ビス−ｔ−ブチルパーオキシ−３，３，５−トリメチルシクロヘキサンなど、（ニ）パーオキシエステル類；例えばジ−ｔ−ブチルパーオキシイソフタレート、ｔ−ブチルパーオキシベンゾエート、ｔ−ブチルパーオキシアセテート、２，５−ジ−メチル−２，５−ジ−ベンゾイルパーオキシ−ヘキサン、ｔ−ブチルパーオキシイソプロピルカーボネート、ｔ−ブチルパーオキシイソブチレートなど、（ホ）ジアシルパーオキサイド類、例えばベンゾイルパーオキサイド、ｍ−トルオイルパーオキサイド、アセチルパーオキサイドなどが挙げられる。
【００２６】
また、アゾ化合物の具体例としては、２，２’−アゾビスイソブチロニトリル、２，２’−アゾビス（２−メチルブチロニトリル）、１，１’−アゾビス（シクロヘキサン−１−カルボニトリル）、１−〔（１−シアノ−１−メチルエチル）アゾ〕ホルムアミド、２−フェニルアゾ−４−メトキシ−２，４−ジメチルバレロニトリル、２，２’−アゾビス（２，４，４−トリメチルペンタン）、２，２’−アゾビス（２−メチルプロパン）などが挙げられる。その他のラジカル発生剤として、ジクミルパーオキサイドを挙げることができる。これらのラジカル発生剤のうちでも特に好ましいのは、１０時間での半減期温度が１２０℃以上のラジカル発生剤である。
【００２７】
成分(A)は、上記(A1)、(A2)、(A3)および(A4)、または、(A2)、(A3)および(A4)を所定量秤量し、溶融状態で反応させることによって得ることができる。成分(A)を構成する各成分の割合は、(A1)０〜６０重量％と(A2)４０〜１００重量％とから構成される重合体成分１００重量部に対し、(A3)を０．１〜５重量部、(A4)を０．０３〜３重量部とする。成分(A)中で(A1)が６０重量部を越えると、最終的に得られる樹脂組成物において、成分(A)の不連続相粒子が特殊な構造とならず、耐衝撃性、寸法安定性が低下する。(A1)を配合すると、最終的に得られる樹脂組成物の耐熱性を向上できるので好ましい。(A1)と(A2)との配合比率は、(A1)／(A2)が好ましくは１０〜６０／９０〜４０であり、より好ましくは１５〜５５／８５〜４５である。
【００２８】
また、成分(A)を調整する際に、(A3)と(A4)とを併用しないと、成分(A)の不連続相粒子が特殊な構造とならず、最終的に得られる樹脂組成物の耐衝撃性が低下し、この樹脂組成物から得られる成形品の寸法安定性も低下する。また、(A3)が５重量部を超えたり、(A4)が３重量部を超えたりすると、成形時の熱安定性が低下し、成形品の外観不良が発生し易い。(A3)の配合量は好ましくは０．５〜４重量部であり、(A4) の配合量は好ましくは０．１〜２重量部である。
【００２９】
溶融状態で反応させる具体的方法としては、溶融状態で混合し反応させる方法が挙げられる。溶融状態で混合し反応させるには、熱可塑性樹脂について一般に実用化されている溶融混練機を使用することができる。溶融混練機で溶融させている間に、変性反応が起こる。溶融混練機としては、例えば、一軸または多軸混練押出機、ロール、バンバリーミキサーなどが挙げられる。
【００３０】
混練押出機を使用する方法によるときは、例えば、（１）(A1)、(A2)、(A3)および(A4)の各成分を予めブレンダーなどで混合し、得られた混合物を混練押出機の上流部側で一括投入（フィード）し、溶融状態で反応させる方法が好適である。
【００３１】
（２）成分(B)
本発明において成分(B)のポリアミドは、主鎖に−ＣＯＮＨ−結合を有し、加熱することにより溶融するものをいう。その代表的なものとしては、ポリアミド−４、ポリアミド−６、ポリアミド−６・６、ポリアミド−４・６、ポリアミド−１２、ポリアミド−６・１０、その他従来から知られている芳香族ジアミン、芳香族ジカルボン酸などの単量体成分を含む結晶性または非晶性のポリアミドが挙げられる。好ましいポリアミドは、ポリアミド−６、ポリアミド−６・６、半芳香族ポリアミドであり、これらと非晶性ポリアミドとを混合したものであってもよい。
【００３２】
成分(B)のポリアミドは、９８重量％の濃硫酸中、温度２５℃で測定した相対粘度が２．１〜３．５の範囲のものが好ましい。相対粘度が２．１未満であると、最終的に得られる樹脂組成物の剛性、寸法安定性、耐衝撃性、外観などが劣り、３．５を超えると最終的に得られる樹脂組成物の成形性が劣り、この樹脂組成物から得られる成形品の外観も悪化するので、いずれも好ましくない。また、ポリアミドは、その末端カルボン酸含量が１００μｅｑ／ｇ以下のものが好ましく、末端カルボン酸と末端アミンの比（末端カルボン酸／末端アミン）が、０．８〜４の範囲のものが好ましい。末端カルボン酸と末端アミンの比が４を超えると、成分(A)と成分(B)との相溶性が低下する。
【００３３】
（３）成分(C)
本発明において成分(C)の無機フィラーは、無機系の粉末をいう。粉末の形態は、球状、立方形状、粒状、針状、板状、繊維状などいずれであってもよい。これら粉末の平均粒子径は、８μｍ以下のものとする。平均粒子径が８μｍを超えると、樹脂組成物から得られる成形品の外観が悪化するので好ましくない。ここで平均粒子径とは、X線透過による液相沈降方式で測定されたD５０をいう。このような測定ができる装置としては、Ｓｅｄｉｇｒａｐｈ粒子径分析器(Micromeritics Instrumentｓ社製、モデル５１００)を挙げることができる。
【００３４】
成分(C)の具体例としては、例えば、酸化チタン、酸化亜鉛、硫酸バリウム、シリカ、炭酸カルシウム、酸化鉄、アルミナ、チタン酸カルシウム、水酸化アルミニウム、水酸化マグネシウム、水炭酸カルシウム、炭酸マグネシウム、硫酸カルシウム、硫酸ナトリウム、亜硫酸カルシウム、珪酸マグネシウム（タルク）、珪酸酸カルシウム（ウォラストナイト）、クレー、ガラスビーズ、ガラスパウダー、ガラス繊維、けい砂、けい石、石英粉、しらす、けいそう土、ホワイトカーボン、鉄粉、アルミニウム粉などが挙げられる。これら無機フィラーは一種でも、二種類以上を併用することもできる。
【００３５】
これらの中で、最終的に得られる樹脂組成物の寸法安定性、剛性を向上させ、良好な外観のものを得るためには、平均粒子径が０．１〜５μｍの板状、針状、繊維状のものが好ましく、これら無機フィラーの中で特に好ましいのは珪酸マグネシウム（タルク）、珪酸カルシウム（ウォラストナイト）であり、さらに好ましくは、平均粒子径が０．２〜３．５μｍ以下の珪酸マグネシウム（タルク）、珪酸カルシウム（ウォラストナイト）である。
【００３６】
本発明において珪酸マグネシウム（タルク）とは、化学組成が含水ケイ酸マグネシウムを意味し、通常ＳｉＯ_２を５８〜６６重量％、ＭｇＯを２８〜３５重量％、Ｈ_２Ｏを約５重量％含んでいる。その他少量成分としてＦｅ_２Ｏ_３が０．０３〜１．２重量％、Ａｌ_２Ｏ_３が０．０５〜１．５重量％、ＣａＯが０．０５〜１．２重量％、Ｋ_２Ｏが０．２重量％以下、Ｎａ_２Ｏが０．２重量％以下等、含有しており比重は約２．７である。
【００３７】
本発明において珪酸カルシウム（ウォラストナイト）とは、針状結晶をもつ天然白色鉱物であり、化学式はＣａＳｉＯ₃で表され、通常ＳｉＯ₂が５０重量％、ＣａＯが４７重量％、その他ＦｅＯ₃、Ａｌ₂Ｏ₃などを含有しており、比重は２．９である。このような珪酸カルシウムを主成分とする繊維状無機フィラーは、通常ウォラストナイトといわれているものである。川鉄鉱業からＰＨ３３０、ＰＨ４５０として、ナイコ社からナイグロス４、ナイグロス５として市販されているものであり、平均アスペクト比が３以上のものが好ましい。
【００３８】
上記無機フィラーは、無処理のままであってもよいが、樹脂成分との親和性または界面結合力を高める目的で、無機表面処理剤、高級脂肪酸またはそのエステル塩などの誘導体、カップリング剤などで処理したものが好ましい。表面処理する際には、非イオン・陽イオン・陰イオン型などの各種の界面活性剤や、各種の樹脂などの分散剤による処理を併せて行うと、機械的強度および混練性の向上の観点から好ましい。
【００３９】
（４）その他の成分
本発明に係る熱可塑性樹脂組成物には、少なくとも、上記三成分を含有するが、これら成分の外に他の各種樹脂添加剤を配合する（含有させる）ことができる。各種樹脂添加剤としては、例えば、熱安定剤、酸化防止剤、耐侯性改良剤、造核剤、発泡剤、難燃剤、耐衝撃改良剤、滑剤、可塑剤、流動性改良剤、染料、顔料、有機充填剤、補強剤、分散剤などが挙げられる。耐衝撃改良剤としては、変性されていないビニル芳香族化合物重合体ブロックＡと共役ジエン系化合物重合体ブロックＢとのブロック共重合体の水素添加物やエチレン−α−オレフィン共重合体などのゴム状重合体が挙げられる。これらゴム状重合体は、成分(A)との重量比で、１０:９０〜９０:１０の範囲で配合する（含有させる）のが好ましい。
【００４０】
（５）各成分の配合割合と配合方法
本発明に係る熱可塑性樹脂組成物は、少なくとも、成分(A)３〜６０重量％と成分(B)４０〜９７重量％からなり、また、成分(A)と成分(B)とよりなる樹脂成分合計１００重量部に対し、さらに成分(C)を５〜６０重量部の割合で配合した（含有させた）ものである。成分(A)と成分(B)との樹脂成分の割合において、成分(A)が３重量％未満では、最終的に得られる樹脂組成物の耐衝撃性や寸法安定性が劣り、６０重量％を越えると、耐衝撃性や寸法安定性が低下し、さらに流動性も低下し、いずれも好ましくない。また、成分(A)と成分(B)との配合比率は、成分(A)／成分(B)が好ましくは５〜５５／９５〜４５であり、より好ましくは１０〜５０／９０〜５０である。
【００４１】
また、成分(A)と成分(B)とより構成される樹脂成分合計１００重量部に対し、成分(C)の配合比率が５重量部未満では、最終的に得られる樹脂組成物の剛性や寸法安定性の改善効果が小さく、６０重量部を越えると耐衝撃性が低下し、いずれも好ましくない。成分(C)の配合比率は、好ましくは１０〜５０重量部であり、より好ましくは１５〜４５重量部である。
【００４２】
本発明に係る熱可塑性樹脂組成物は、少なくとも、上記成分および比率で構成される。特に優れた耐衝撃性および寸法安定性（低線膨張係数）、剛性を発揮する熱可塑性樹脂組成物のペレット、または、射出成形品から切り出した小片について、そのミクロ形態｛微細構造(fine texture)、モルフォロジー(morphology)など｝を、透過型電子顕微鏡（ＴＥＭ）により観察すると、特異な形態を呈していることが分かった。特異なミクロ形態は、ペレットまたは射出成形品から小片を、例えばクライオ装置を装備した超ミクロトーム（ライカ社製、ULTRCUT CUT）で、ダイヤモンドナイフを使用し、−１００℃の温度で厚さ１００n超薄切片に切り出し、切り出した小片の表面を四酸化オスミウムおよび四酸化ルテニウムで染色した後、透過型電子顕微鏡（例えば、日本電子社製、型式：ＪＥＭ１２００ＥＸII型）を用いて容易に観察することができる。
【００４３】
小片の表面を染色した後、透過型電子顕微鏡によって観察すると、樹脂成分のうち、成分(A)が最も濃色に観察され、成分(C)は樹脂成分に比べ重原子を多く含んでいるため無染色でも暗色に観察される。このような方法で観察し、画像解析装置で不連続相（ドメイン相）の粒子形状、輪郭などを解析したところ、次のような特性を示すことが分かった。すなわち、▲１▼透過型電子顕微鏡写真から、成分(A)が不連続相、成分(B)が連続相（マトリックス相）となり、成分(C)は主に成分(B)の連続相中に存在すること。
【００４４】
また、▲２▼成分(A)は成分(B)の連続相中に、凹凸状の輪郭を呈した粒子として存在すること、▲３▼凹凸状の輪郭を呈した粒子の平均粒径は３μｍ以下が好ましいこと、さらに好ましいのは１μｍ以下であること。さらに、▲４▼成分(B)の連続相と成分(A)の不連続相との界面は、成分(A)の凹凸状の輪郭を有する粒子に対応した凹凸を形成し、両者の界面には隙間がないこと。
【００４５】
▲５▼この凹凸状の輪郭を呈して成分(B) の中に不連続相として分散する成分(A)の粒子につき、成分(A)と成分(B)との凹凸状の界面輪郭を画像処理解析装置（例えば日本アビオニクス社製、スピカ）に読み込ませて二値化抽出し、成分(A)の凹凸状輪郭の全長を計測し、この値をＬａする。
凹凸状を呈するの成分(A)の輪郭をスムージングしたときの界面周囲長（凹凸状輪郭の全体の長さ）をLbとするとき、両者の比（界面周囲長の比）（Ｌａ／Ｌｂ）が１．１５以上の特殊な界面構造を有すること、特に好ましくは１．２以上であること。換言すれば、界面周囲長の比（Ｌａ／Ｌｂ）が１．１５以上、好ましくは１．２以上の凹凸の激しい界面構造が、樹脂組成物に対する外部からの衝撃力を吸収して耐衝撃性を向上させ、寸法安定性に寄与するものと推定される。
【００４６】
なお、本発明において成分(A)の輪郭のスムージングとは、図１に実線で示した凹凸状の界面輪郭11を、画像処理解析装置によって円周（Lｂ）を算出することである。図１に実線で示した凹凸状の界面輪郭を呈する成分(A)の粒子について、画像処理解析装置で４連結膨張を２０回繰り返した後、細線化処理して界面輪郭の凹凸をなくしてスムージングした後の円周22（Lｂ）は、図１において点線で示される。
【００４７】
本発明に係る熱可塑性樹脂組成物のミクロ形態｛微細構造（fine texture）またはモルフォロジー（morphology）｝を、上記のような特定なものとするには、溶融混合法によるのが好ましい。例えば、▲１▼まず、成分(A)を溶融状態で反応させ、続いて混練押出機の中流部分で成分(B)を投入し、成分(A)と成分(B)を溶融反応させ、さらに混練押出機下流部分から成分(C)を溶融混合し、熱可塑性樹脂組成物のペレットとする方法が挙げられる。
【００４８】
その他、▲２▼ペレット化した成分(A)と成分(B)を混練押出機に投入し、成分(A)と成分(B)を溶融反応させ、混練押出機の中流以降の部分から成分(C)を溶融混合し、熱可塑性樹脂組成物をペレット化する方法などが挙げられる。さらには、▲３▼ペレット化した成分(A)とペレット状の成分(B)とを混練押出機に投入し、溶融状態で混練してペレット化して、得られたペレットに成分(C)を混練押出機に投入して溶融混合し、熱可塑性樹脂組成物のペレットとする方法も挙げられる。
【００４９】
また、前記した成分(A)の変性物を得る方法において、(A1)、(A2)、(A3)および（A4）の各成分を同時に溶融状態で反応させて変性物を用いた場合のみ、界面周囲長の比（Ｌａ／Ｌｂ）が１．１５以上である特殊な界面構造を有する熱可塑性樹脂組成物を得ることができる。(A1)、(A3)および（A4）を溶融状態で反応させた変性物と、(A2)、（A3）および（A4）を溶融状態で反応させた変性物を混合して、前記の界面周囲長の比（Ｌａ／Ｌｂ）が１．１５以上である特殊な界面構造を有する熱可塑性樹脂組成物を得ることはできないので、混合（添加）順序は極めて重要である。
【００５０】
なお、成分(A)、成分(B)および成分(C)を溶融混合する場合も、予め成分(A)と成分(B)とを溶融反応させ、その後成分(C)を溶融混合させて製造した場合のみ、前記の界面周囲長の比（Ｌａ／Ｌｂ）が１．１５以上である特殊な界面構造を有する熱可塑性樹脂組成物を得ることができ、耐衝撃性、寸法安定性、剛性に優れた熱可塑性樹脂組成物が得られるので、混合（添加）順序に留意する必要がある。
【００５１】
（６）熱可塑性樹脂組成物の用途
本発明に係る熱可塑性樹脂組成物から成形品を製造する方法は、特に限定されるものではなく、熱可塑性樹脂について一般に採用されている成形法、すなわち射出成形法、中空成形法、押出成形法、シート成形法、熱成形法、回転成形法、積層成形法、プレス成形法などを採用することができる。本発明の熱可塑性樹脂組成物は、電機機器部品、電子機器部品、自動車部品などの製造用原料として広範囲の分野に利用できる。特に自動車外装部品製造用原料として有用である。
【００５２】
【実施例】
以下に本発明を実施例によって、詳しく説明するが、本発明はこれらの範囲内に限定されるものではない。実施例および比較例において使用した原材料は、次のような物性・特性を有するものである。実施例および比較例において使用した原材料は、次のような物性・特性を有するものである。なお、以下の実施例、比較例において配合量は重量部を意味する。
【００５３】
成分(A)：
(A1)ＰＰＥ：ポリフェニレンエーテル（三菱エンジニアリングプラスチックス社製のポリ−２，６−ジメチル−１，４−フェニレンエーテルであって、クロロホルム中、温度３０℃で測定した固有粘度が０．４０ｄｌ／ｇのもの）である。
(A2)ＳＥＢＳ−１：スチレン含有量２９重量％、分子量８０，０００であって、Ａ−Ｂ−Ａ型のスチレン−エチレン／ブチレン−スチレンブロック共重合体（シェル化学社製、商品名：クレイトンＧ１６５０）である。
【００５４】
(A2)ＳＥＢＳ−２：スチレン含有量３３重量％、分子量２００，０００あって、Ａ−Ｂ−Ａ型のスチレン−エチレン／ブチレン−スチレンブロック共重合体（シェル化学社製、商品名：クレイトンＧ１６５１）である。
(A２)ＳＥＢＳ−３：スチレン含有量２９重量％、分子量４９，０００あって、Ａ−Ｂ−Ａ型のスチレン−エチレン／ブチレン−スチレンブロック共重合体（シェル化学社製、商品名：クレイトンＧ１６５２）である。
(A３)不飽和酸無水物および／または不飽和酸：無水マレイン酸（三菱化学社製、商品名：無水マレイン酸）である。
【００５５】
(A4)パーカドックス１４：１、３−ビス（２−ｔ−ブチルパーオキシイソプロピル）ベンゼン（化薬アクゾ社製、商品名：パーカドックス１４、半減期の１０時間後の分解温度が１２１℃）である。
(A4) パーヘキサ２５Ｂ：２、５−ジメチル−２、５−ジ（ｔ−ブチルペロキシ）ヘキサン（日本油脂社製、商品名：パーヘキサ２５Ｂ、半減期の１０時間後の分解温度が１１８℃）である。
(A5)ＥＢＲ：エチレン−ブテン共重合体（三井石油化学工業社製、商品名：タフマーＡ−４０８５）である。
【００５６】
成分(B)（ポリアミド）：
(B-1)：ポリアミド６（三菱エンジニアリングプラスチックス社製、商品名：ノバミッド１０１０Ｊ、９８％の濃硫酸中、温度２３℃で測定した相対粘度が２．５ｄｌ／ｇ、末端カルボン酸／末端アミン比が２．６）である。
(B-2)：ポリアミド６（カネボウ社製、商品名：カネボウナイロンＭＣ１００Ｌ、９８％の濃硫酸中、温度２３℃で測定した相対粘度が２．２ｄｌ／ｇ、末端カルボン酸／末端アミン比が２．３）である。
(B-3)：ポリアミド６（三菱エンジニアリングプラスチックス社製、商品名：ノバミッド１００５Ｊ、９８％の濃硫酸中、温度２３℃で測定した相対粘度が２．０ｄｌ／ｇ、末端カルボン酸／末端アミン比が４．９）である。
(B-4)：ポリアミド６（カネボウ社製、商品名：カネボウナイロンＭＣ１１２Ｌ、９８％の濃硫酸中、温度２３℃で測定した相対粘度が２．７ｄｌ／ｇ、末端カルボン酸／末端アミン比が１．３）である。
【００５７】
成分(C)（無機フィラー）：
(C-1)：珪酸マグネシウム（タルク）（松村産業製、商品名：ハイフィラー＃５０００ＰＪ、平均粒子径：１．８μｍ）である。
(C-2)：珪酸カルシウム（ウォラストナイト）（川鉄鉱業製、ＰＨ４５０、平均粒子径：３．８μｍ）である。
【００５８】
［成分(A)の調整］
上記(A1)、(A2)、(A3)、(A4)の各成分を、表―１に示す割合で秤量し、ヘンシェルミキサーによって均一に混合した後、二軸押出機（スクリュー直径３０ｍｍ、Ｌ／Ｄ＝４２）を使用して、シリンダー温度２４０℃、スクリュー回転数４００ｒｐｍの条件下で溶融し反応させ、ペレット化して成分（Ａ−１）〜（Ａ−１１）を得た。
【００５９】
【表１】

【００６０】
［試験片の作製］
樹脂組成物を、射出成形機（東芝機械社製、形式：ＩＳ１５０）を使用し、シリンダー温度２８０℃、金型温度８０℃の条件で成形して、ＡＳＴＭ試験片、および直径１００mm×厚さ３ｍｍの円盤状試験片を作成した。
【００６１】
［評価方法］
（1）ミクロ形態の観察：上記円盤状試験片から、クライオ装置(REICHERT-NSSEI FCS)を装着した超ミクロトーム（ライカ社製、ULTRACUT CUT）で、ダイヤモンドナイフを使用し、温度−１００℃で厚さ１００nmの超薄切片を切り出した。切り出した切片を、四酸化オスミウムおよび四酸化ルテニウムで染色した後、透過型電子顕微鏡（日本電子社製、型式：ＪＥＭ１２００ＥＸII型）を使用してミクロ形態（分散状態、界面周囲長の比）を観察した。次に、粒子の界面をトレースした画像を、画像処理解析装置（日本アビオニクス製、装置名：スピカ）に読み込ませて界面輪郭を二値化抽出し、スムージングした後の円周（Lｂ）を算出し、界面周囲長の比（Ｌａ／Ｌｂ）を計測した。この操作を２０個以上の不連続相について計測し、その平均値を算出した。なお、凹凸状の輪郭を呈する粒子のみかけ平均直径(Ｌｂ)の測定は、画像処理解析装置で４連結膨張を２０回繰り返した後、細線化処理して算出した。
【００６２】
(2)流動性（ＭＦＲ）：ＪＩＳ Ｋ７２１０に準拠し、温度２８０℃、荷重５ｋｇの条件で測定した。
(3)曲げ弾性率：ＡＳＴＭ Ｄ７９０に準拠して測定した。
(4)耐衝撃性（アイゾット衝撃強度）：ＡＳＴＭ Ｄ２５６に準拠し、厚さが３．２mm、ノッチ付きの試験片で測定した。
【００６３】
(5)寸法安定性（線膨張係数）：ＡＳＴＭ Ｄ６９６に準拠して線膨張係数を測定した。ただし、測定温度範囲は２３〜８０℃とした。
(6)外観：円盤状成形品の表面外観を目視観察し、蛍光灯の像が極めてくっきりと写るものを◎、くっきりと写るものを○、少し揺らいで写るものを△、揺らいで写るものを×として評価した。
【００６４】
［実施例１および比較例１〜比較例２］
表―２に示す割合で成分(A)と成分(B)とを秤量し、タンブラーミキサーによって均一に混合した。この混合物を、二軸押出機（日本製鋼所製、ＴＥＸ３０ＸＣＴ、Ｌ／Ｄ＝４２、バレル数１２）を使用し、シリンダー温度２３０℃、スクリュー回転数４００ｒｐｍの条件で、二軸押出機のバレル１より投入（フィード）して溶融反応させ、さらに二軸押出機のバレル５より成分(C)を投入し、溶融混練して樹脂組成物を調製した。得られた樹脂組成物から前記したように射出成形法で試験片を作成し、得られた試験片につき前記した方法で種々の物性を測定し、測定結果を表―２に示した。
【００６５】
［比較例３］
成分(C)を成分(A)、成分(B)と共にタンブラーミキサーで均一に混合し、バレル１より二軸押出機（実施例１で使用したものに同じ）に一括投入した外は、実施例１におけると同様の手順で樹脂組成物を調製した。得られた樹脂組成物につき、実施例１におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―２に示した。
【００６６】
［実施例２および比較例４］
実施例１に記載の例において、ポリアミドを相対粘度が異なるものに変えた外は、同例におけると同様にして樹脂組成物を調製した。得られた樹脂組成物につき、実施例１におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―２に示した。
【００６７】
［実施例３および比較例５、比較例６］
実施例１に記載の例において、ＰＰＥとＳＥＢＳとの重量比と、ＳＥＢＳの分子量が異なるものに変えた外は、同例におけると同様にして樹脂組成物を調製した。得られた樹脂組成物につき、実施例１におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―２に示した。
【００６８】
【表２】

【００６９】
表―１と表―２から、次のことが明らかになる。
(1)実施例１の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．４５と大きく、連続相と不連続相との界面が凹凸状の輪郭を呈する特殊な界面構造を有し、耐衝撃性と寸法特性、剛性のバランスに優れている。
(2)これに対し、成分(A)としてラジカル発生剤を添加しなかった(A2)を配合した比較例１の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．０３と小さく、実施例１の樹脂組成物とは成分(A)の分散粒子の輪郭が異なり、耐衝撃性、寸法安定性に劣る。
(3)また、ＳＥＢＳ−１に代えてＥＢＲを配合した比較例２の樹脂組成物も、実施例１の樹脂組成物とは分散粒子の輪郭が異なり、寸法安定性に劣る。
(4)さらに、成分(A)、成分(B)および成分(C)を、混練押出機に一括投入して溶融混練した比較例３の樹脂組成物も、（Ｌａ／Ｌｂ）の値が１．１３と小さく、実施例１の樹脂組成物とは分散粒子の輪郭が異なり、寸法安定性、剛性に劣る。
【００７０】
(5)相対粘度が２．２のポリアミドを配合実施例２の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．４２と大きく、実施例１のものと同様に、連続相と不連続相との界面が凹凸状の輪郭を呈する特殊な界面構造を有し、耐衝撃性と寸法特性、剛性のバランスに優れている。
(6)これに対し、ポリアミドの実施例を２．０とした比較例４の組成物は、（Ｌａ／Ｌｂ）の値が１．１０と小さく、実施例１、実施例２のものとは分散粒子の輪郭が異なり、耐衝撃性、寸法安定性、剛性に劣る。
(7) 成分(A)として、ＰＰＥとＳＥＢＳ−と１の重量比を５０対５０とした(A4)を配合して実施例３の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．３７と大きく、連続相と不連続相との界面が凹凸状の輪郭を呈する特殊な界面構造を有し、耐衝撃性と寸法安定性、剛性のバランスに優れている。
(8)これに対し、成分(A)として、ＰＰＥとＳＥＢＳとの重量比を７０対３０とした比較例５のもの、および成分(A) を構成する(A2)をＳＥＢＳ−２（分子量の大きいもの）とした比較例６の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．０５（比較例５）、１．０６（比較例６）と小さく、いずれも実施例１、実施例３の樹脂組成物とは分散粒子の輪郭が異なり、寸法安定性、剛性に劣る。
【００７１】
［実施例４〜実施例６および比較例７、比較例８］
表―３に示す割合で成分(A)と成分(B)とを秤量し、タンブラーミキサーによって均一に混合した。この混合物を、二軸押出機（実施例１で使用したものと同じ）を使用し、シリンダー温度２３０℃、スクリュー回転数４００ｒｐｍの条件で、バレル１より二軸押出機に投入して溶融反応させ、さらに、バレル５より成分(C)を二軸押出機に投入し、溶融混練して樹脂組成物を調製した。得られた樹脂組成物から前記したように射出成形機で試験片を作成し、得られた試験片につき前記した方法で種々の物性を測定し、測定結果を表―２に示した。
【００７２】
［比較例９］
実施例４に記載の例において、成分(C)を成分(A)、成分(B)と共にタンブラーミキサーで均一に混合し、得られた混合物をバレル１より二軸押出機に投入した外は、実施例４におけると同様の手順で樹脂組成物を調製した。得られた樹脂組成物につき、実施例４におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―３に示した。
【００７３】
［実施例７］
実施例１に記載の例において、成分(C)の量を変えた外は、同例におけると同様にして樹脂組成物を調製した。得られた樹脂組成物につき、実施例１におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―３に示した。
【００７４】
[実施例８]
実施例４に記載の例において、成分(C)の種類を変えた外は、同例におけると同様にして樹脂組成物を調製した。得られた樹脂組成物につき、実施例４におけると同様の手順で試験片を作成して物性を測定し、測定結果を表―３に示した。
【００７５】
【表３】

【００７６】
表―１と表―３から、次のことが明らかになる。
(1) 実施例４〜実施例６の樹脂組成物は、（Ｌａ／Ｌｂ）の値が１．３５と大きく、連続相と不連続相との界面が凹凸状の輪郭を呈する特殊な界面構造を有し、耐衝撃性と寸法特性、剛性のバランスに優れている。
(2) これに対し、ラジカル発生剤を添加しなかった比較例７の樹脂組成物は、実施例４の組成物とは界面構造が異なり、耐衝撃性、寸法安定性に劣り、また、(A2)としてＥＢＲを配合した比較例８の樹脂組成物も、実施例４の組成物とは界面構造が異なり、寸法安定性に劣る。
(3) 成分(A)、成分(B)および成分(C)を、混練押出機に一括投入して溶融混練した比較例９の樹脂組成物もまた、（Ｌａ／Ｌｂ）の値が１．１２と小さく、実施例４の樹脂組成物とは界面構造が異なり、寸法安定性、剛性に劣る。
(4) 実施例７、実施例８の樹脂組成物は、実施例１、実施例４の樹脂組成物と同様に、連続相と不連続相との界面が凹凸状の輪郭を呈する特殊な界面構造を有し、耐衝撃性と寸法特性、剛性のバランスに優れている。
【００７７】
【発明の効果】
本発明に係る熱可塑性樹脂組成物は、以上詳細に説明したとおりであり、次のような特別に優れた効果を奏し、その産業上の利用価値は極めて大である。
１．本発明に係る熱可塑性樹脂組成物は、溶融流動性が高く加工性が優れて成形し易い。
２．本発明に係る熱可塑性樹脂組成物は、耐衝撃性、寸法安定性および剛性に優れ、かつ、これらの物性が好ましくバランスしている。
３．本発明に係る熱可塑性樹脂組成物は、寸法安定性に優れているので、
金属部品と組み合わせて使用しても、寸法差や噛み合い不良などの不具合が生じ難い。
４．本発明に係る熱可塑性樹脂組成物からは、表面外観、塗装密着性などに優れた成形品を製造することができるので、電機機器部品、電子機器部品、自動車部品製造用材料として、広範囲の分野に利用でき、特に。自動車外装部品製造用材料として、有用である。
【図面の簡単な説明】
【図１】 スムージングを説明する模式図である。
【符号の説明】
11：成分(A)の凹凸の輪郭
22：スムージングした後の円周[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermoplastic resin composition pellet or an injection-molded product (hereinafter sometimes simply referred to as a thermoplastic resin composition). Manufacturing method About. More specifically, the present invention relates to a thermoplastic resin composition that is excellent in fluidity, impact resistance, dimensional stability, rigidity, and the like, and that can provide a molded product having an excellent appearance. Electrical equipment parts, electronic equipment parts, automobiles The present invention relates to a thermoplastic resin composition that can be used in a wide range as a raw material for manufacturing automotive parts and the like, and particularly useful as a material for manufacturing automotive exterior parts, and a method for manufacturing the same.
[0002]
[Prior art]
Polyamide is widely used as a representative engineering plastic with excellent mechanical properties such as moldability, chemical resistance, tensile strength, and bending strength. However, dimensional stability, heat resistance, impact resistance, etc. There is a drawback that the physical properties of are inferior. Polyphenylene ether, on the other hand, is excellent in heat resistance, mechanical properties, electrical properties, etc., but has the disadvantage that it is difficult to mold due to low melt flowability and inferior processability, as well as chemical resistance and impact resistance. There is a drawback that it is also inferior.
[0003]
To solve the above-mentioned drawbacks of polyamide and polyphenylene ether at the same time, polyphenylene ether, polyamide, rubber-like substance, (1) carbon-carbon double bond or carbon-carbon triple bond in the molecule, and (2) There has been proposed a resin composition comprising a compound having a carboxylic acid group, an acid anhydride group, an acid amide group, etc., having no chemical phase separation and excellent chemical resistance and impact resistance (see Patent Document 1).
[0004]
In addition, as a technique for improving impact resistance by keeping the amount of rubber-like substance constant, discontinuous resin compositions exhibiting a micro-dispersed form {continuous phase (matrix phase)-discontinuous phase (domain layer) structure} There is a method of refining dispersed particles that form a phase. For example, a resin composition comprising modified polyphenylene ether (A), polyamide (B), hydrogenated block copolymer elastomer (C) (rubber-like substance), and component (A) dispersed in the resin composition There has been proposed an impact-resistant polyamide composition obtained by melt-kneading a modified polyphenylene ether, a modified hydrogenated block copolymer elastomer and a polyamide having a fine dispersed phase diameter of 0.6 μm or less. (Patent Document 2).
[0005]
Further, polyphenylene ether (b) is present as a primary dispersed phase in polyamide (a), and hydrogenated block copolymer of alkenyl aromatic polymer and conjugated diene polymer (c) (rubber-like substance) in (b). ) Form a secondary dispersed phase, the average particle diameter of (c) is in the range of 0.01 to 5 μm, and the melt viscosity ratio (ηc / ηb) of (c) and (b) is 0.01 to 10 A resin composition excellent in impact resistance in the range of (2) has been proposed (Patent Document 3).
[0006]
However, by making the dispersed particle size finer, a resin composition having excellent impact resistance can be obtained, but the dimensional stability (linear expansion coefficient) of the obtained molded product is still not improved. For example, when a molded product obtained from a resin composition is used in combination with a metal part, the linear expansion coefficient of the resin molded product is too larger than that of the metal part, and when used in a high temperature environment, a dimensional difference or There was a defect that a problem such as poor meshing occurred and the rigidity was insufficient.
[0007]
In addition, when a paint is applied to the surface of a resin molded product and this resin molded product is used in a high temperature environment, the linear expansion coefficient of the paint and the resin material is different. There were problems that the film peeled off or fine cracks were formed on the painted surface, which deteriorated the appearance and design. In particular, exterior parts for automobiles such as fenders, door panels, and roof panels can be made lighter, have greater design freedom, and can be made into modules. Yes, the material used for this application is a resin that exhibits a high level of properties in terms of impact resistance, dimensional stability (linear expansion coefficient), rigidity, fluidity, appearance, etc., compared to conventional resin materials Materials have come to be required.
[0008]
In general, in order to improve dimensional stability and rigidity, a method of incorporating (or including) an inorganic filler in a resin composition is adopted, but when an inorganic filler is included, impact resistance is significantly reduced, Since the appearance of the obtained molded product is also deteriorated, its use has been remarkably limited. In addition, for the purpose of improving the impact resistance of resin compositions containing inorganic fillers, increasing the amount of rubber-like substances will greatly reduce dimensional stability and rigidity, so impact resistance, dimensional stability and rigidity. It was necessary to improve the balance.
[0009]
Therefore, the present inventors have obtained a composition having an excellent balance between impact resistance and dimensional stability, in which a rubber-like substance is dispersed in a network in polyamide and the rubber-like substance is present at the interface between polyamide and polyphenylene ether. A resin composition in which an inorganic filler is present in polyamide and has excellent impact resistance, dimensional stability, and rigidity has been proposed (Patent Documents 4 and 5). However, although these technologies are excellent in impact resistance and dimensional stability, fluidity is sacrificed because the rubber-like substance is dispersed in a network, and the rigidity is insufficient, so that the application is limited. I found out.
[0010]
Furthermore, in order to improve the above-mentioned drawbacks, a resin composition in which a rubber-like substance is present as a dispersed phase in polyamide, polyphenylene ether is present in the rubber-like substance, and an inorganic filler is mainly present in the polyamide has been proposed. (Patent Document 6). However, the above technique does not satisfy the balance of impact resistance, dimensional stability and rigidity sufficiently, and there is a disadvantage that the appearance of the molded product is sacrificed when the balance of these physical properties is improved.
[0011]
On the other hand, in order to improve the impact resistance, dimensional stability and rigidity of polyamide, various compositions comprising polyamide, rubber-like substance and inorganic filler have been proposed. For example, polyamide, inorganic filler, modified styrene / olefin A polyamide composition composed of a polymer (Patent Document 7) has been proposed. However, the balance between impact resistance, dimensional stability, and rigidity cannot be said to be sufficient with the conventional technology. If the content of rubber-like substances (mixing amount) is increased to improve impact resistance, dimensional stability Since the rigidity is greatly reduced, it is necessary to improve the balance between impact resistance, dimensional stability and rigidity.
[0012]
Therefore, the present inventors have proposed a resin composition excellent in impact resistance, dimensional stability and rigidity in which a rubber-like substance is dispersed in a network in polyamide and an inorganic filler is present in the polyamide (Patent Document). 8). However, although these technologies are excellent in impact resistance and dimensional stability, the rubber-like substance is dispersed in a network, so that there is still a disadvantage that fluidity and rigidity are sacrificed. Impact resistance and dimensional stability There has been a strong demand for a material having excellent rigidity, fluidity and appearance.
[0013]
[Patent Document 1]
JP 56-49753 A
[Patent Document 2]
Japanese Patent No. 2557637
[Patent Document 3]
Japanese Patent No. 2798722
[Patent Document 4]
Japanese Patent Laid-Open No. 7-18187
[Patent Document 5]
Japanese Patent Laid-Open No. 7-18188
[Patent Document 6]
JP 2002-105343 A
[Patent Document 7]
Japanese Examined Patent Publication No. 8-11782
[Patent Document 8]
JP 7-18189 A
[0014]
[Problems to be solved by the invention]
The present inventors have solved the above-mentioned disadvantages existing in the prior art, exhibiting good chemical resistance and heat resistance, and in particular, linear expansion coefficient so as not to cause malfunction even when used in combination with metal parts. Is a thermoplastic resin composition pellet or injection-molded product that has improved dimensional stability by lowering and excellent in impact resistance, rigidity, fluidity and appearance Manufacturing method The present invention has been completed as a result of intensive studies aimed at providing the above.
[0015]
[Means for Solving the Problems]
To solve the above problem, The present invention Then, the component (A): (A1) 0 to 60% by weight of polyphenylene ether and (A2) block copolymer hydrogenated product of vinyl aromatic compound polymer block A and conjugated diene compound polymer block B 40 to 40% (A3) 0.1 to 5 parts by weight of an unsaturated acid anhydride and / or unsaturated acid, (A4) 0.03 to 3 parts by weight of a radical generator are melted with respect to 100 parts by weight of a polymer and 100 parts by weight. 3 to 60% by weight of the modified product obtained by reacting in the state and 100 parts by weight of the resin component consisting of 40 to 97% by weight of the component (B): Component (C): average particle size of 8 μm or less A thermoplastic resin composition pellet or injection-molded product containing 5 to 60 parts by weight of an inorganic filler, and the micro morphology of the thermoplastic resin composition pellet or injection-molded product is observed with an electron microscope. At this time, the component (B) forms a continuous phase, and the component (B) is dispersed in particles having an uneven contour to form a discontinuous phase in the continuous phase of the component (B). And, when the interface perimeter of the contour exhibiting the concavo-convex shape of the component (A) and the component (B) is La and the interface perimeter when the contour exhibiting the concavo-convex shape is smoothed is Lb, the ratio between the two ( A thermoplastic resin composition pellet or an injection-molded article is provided, wherein La / Lb) is 1.15 or more.
[0016]
Also, The present invention Then, in producing a thermoplastic resin composition pellet or injection-molded article containing the component (A), the component (B) and the component (C) comprising the following components, first, the component (A) and the component (B) are previously prepared. Then, the component (C) is melt-mixed, and the component (B) forms a continuous phase when the resulting thermoplastic resin composition pellets or injection molded product is observed with an electron microscope. In the continuous phase of the component (B), the component (A) is dispersed in particles having a concavo-convex contour to form a discontinuous phase, and the component (A) and the component ( B) When the interface perimeter of the contour exhibiting unevenness is La and the interface perimeter when smoothing the contour exhibiting the unevenness is Lb, the ratio (La / Lb) of both is 1.15 or more. Thermoplastic resin composition pellets or injection, characterized in that To provide a method of manufacturing a molded article.
Component (A): (A1) 0 to 60% by weight of polyphenylene ether,
(A2) The vinyl aromatic compound polymer block A and the conjugated diene compound polymer block B block copolymer hydrogenated with 100 to 100 parts by weight of the hydrogenated product, and (A3) unsaturated acid 0.1 to 5 parts by weight of anhydride and / or unsaturated acid, 3 to 60% by weight of a modified product obtained by reacting 0.03 to 3 parts by weight of (A4) radical generator in a molten state, and
Component (B): 100 parts by weight of a resin component comprising 40 to 97% by weight of polyamide,
Component (C): It contains 5 to 60 parts by weight of an inorganic filler having an average particle size of 8 μm or less.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
(1) Component (A)
Component (A) in the thermoplastic resin composition according to the present invention (hereinafter sometimes simply referred to as resin composition) is (A1) polyphenylene ether (hereinafter sometimes simply referred to as (A1)). }, (A2) hydrogenated block copolymer of vinyl aromatic compound polymer block A and conjugated diene compound polymer block B (hereinafter sometimes simply referred to as (A2)), (A3) Each component of a saturated acid anhydride and / or an unsaturated acid {hereinafter simply abbreviated as (A3)} and (A4) a radical generator {hereinafter simply abbreviated as (A4)} Is a modified product obtained by reacting in a molten state, or a modified product obtained by reacting the components (A2), (A3) and (A4) in a molten state.
[0018]
In the present invention, (A1) polyphenylene ether is a polymer having a structural unit represented by the following general formula [I] in the main chain, and may be either a homopolymer or a copolymer.
[0019]
[Chemical 1]

[0020]
Specific examples of (A1) polyphenylene ether include poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2 , 6-dipropyl-1,4-phenylene) ether, poly (2-methyl, 6-ethyl-1,4-phenylene) ether, poly (2-methyl, 6-propyl-1,4-phenylene) ) Ether. Of these, poly (2,6-dimethyl-1,4-phenylene) ether is preferred. Preferred (A1) polyphenylene ethers are those having an intrinsic viscosity of 0.3 to 0.5 dl / g measured in chloroform at a temperature of 30 ° C. If the intrinsic viscosity is less than 0.3 dl / g, the impact resistance of the finally obtained resin composition is insufficient, and if it exceeds 0.5 dl / g, the moldability of the finally obtained resin composition deteriorates. , The appearance of the molded product is also deteriorated, and neither is preferable.
[0021]
In the present invention, the hydrogenated block copolymer (A2) is a block copolymer elastic body of a vinyl aromatic compound polymer block A and a conjugated diene compound polymer block B, which is hydrogenated. It means a hydrogenated block copolymer with reduced aliphatic unsaturated groups in block B. The arrangement of the blocks A and B may be any structure such as a linear structure or a branched structure (radical teleblock). Moreover, among these structures, a random chain derived from a random copolymer portion of a vinyl aromatic compound and a conjugated diene compound may be included in part. Among these structures, a linear structure is preferable, an ABA type triblock structure is particularly preferable, and a diblock structure may be included.
[0022]
The vinyl aromatic compound of the hydrogenated product of the (A2) block copolymer is preferably styrene, α-methylstyrene, paramethylstyrene, vinyltoluene, vinylxylene, and more preferably styrene. The conjugated diene compound is preferably 1,3-butadiene or 2-methyl-1,3-butadiene. The proportion of the repeating unit derived from the vinyl aromatic compound in the hydrogenated product of the (A2) block copolymer is preferably in the range of 10 to 70% by weight, and more preferably in the range of 10 to 40% by weight. Of the aliphatic chain portion in the block copolymer, the proportion of unsaturated bonds derived from the conjugated diene compound and remaining without being hydrogenated is preferably 20% or less, and more preferably 10% or less. In addition, about 25% or less of the aromatic unsaturated bond derived from the vinyl aromatic compound may be hydrogenated.
[0023]
The number average molecular weight of these (A2) hydrogenated block copolymers is preferably 180,000 or less, more preferably 120,000 or less. When the molecular weight exceeds 180,000, the discontinuous phase particles dispersed in the resin composition do not have a special structure, are inferior in impact resistance and dimensional stability, and are inferior in molding processability.
[0024]
In the present invention, (A3) unsaturated acid anhydride and / or unsaturated acid include maleic anhydride, itaconic anhydride, chloromaleic anhydride, citraconic anhydride, butenyl succinic anhydride, tetrahydrophthalic anhydride, and these Examples include acids. Of these, maleic anhydride and / or maleic acid are particularly preferred. These unsaturated acid anhydrides and / or unsaturated acids may be used singly or in combination of two or more.
[0025]
In the present invention, examples of the (A4) radical generator include organic peroxides and azo compounds. Specific examples of the organic peroxide include (i) hydroperoxides; for example, t-butyl-hydroperoxide, cumene-hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 1, (3) Di-alkyl peroxides such as 1,3,3-tetramethylbutyl-hydroperoxide, p-menthane-hydroperoxide, diisopropylbenzene hydroperoxide, such as 2,5-dimethyl-2,5- Di (t-butylperoxy) hexyne-3, di-t-butyl-peroxide, t-butyl-cumyl-peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, (C) peroxyketals such as di-cumyl peroxide, such as 2,2-bis-t Butylperoxy-butane, 2,2-bis-t-butyl-peroxy-octane, 1,1-bis-t-butylperoxy-cyclohexane, 1,1-bis-t-butylperoxy-3,3 (D) peroxyesters such as 5-trimethylcyclohexane; for example, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, t-butylperoxyacetate, 2,5-di-methyl-2,5 -Di-benzoylperoxy-hexane, t-butylperoxyisopropyl carbonate, t-butylperoxyisobutyrate, etc. (e) diacyl peroxides such as benzoyl peroxide, m-toluoyl peroxide, acetyl peroxide Etc.
[0026]
Specific examples of the azo compound include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile. ), 1-[(1-cyano-1-methylethyl) azo] formamide, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, 2,2′-azobis (2,4,4-trimethylpentane) ), 2,2′-azobis (2-methylpropane) and the like. Examples of other radical generators include dicumyl peroxide. Of these radical generators, particularly preferred are radical generators having a half-life temperature of 120 ° C. or more in 10 hours.
[0027]
Component (A) is obtained by weighing a predetermined amount of (A1), (A2), (A3) and (A4), or (A2), (A3) and (A4) and reacting them in a molten state. be able to. The proportion of each component constituting the component (A) is such that (A3) is 0. 100 parts by weight of the polymer component composed of (A1) 0 to 60% by weight and (A2) 40 to 100% by weight. 1 to 5 parts by weight, and (A4) is 0.03 to 3 parts by weight. When component (A1) exceeds 60 parts by weight in component (A), the discontinuous phase particles of component (A) will not have a special structure in the final resin composition, impact resistance and dimensional stability Sexuality decreases. It is preferable to add (A1) since the heat resistance of the finally obtained resin composition can be improved. The blending ratio of (A1) and (A2) is preferably (A1) / (A2) of 10-60 / 90-40, more preferably 15-55 / 85-45.
[0028]
Further, when adjusting component (A), if (A3) and (A4) are not used in combination, the discontinuous phase particles of component (A) do not have a special structure, and the resin composition finally obtained The impact resistance of the resin composition decreases, and the dimensional stability of a molded product obtained from this resin composition also decreases. On the other hand, if (A3) exceeds 5 parts by weight or (A4) exceeds 3 parts by weight, the thermal stability at the time of molding is lowered, and the appearance of the molded product tends to be poor. The amount of (A3) is preferably 0.5 to 4 parts by weight, and the amount of (A4) is preferably 0.1 to 2 parts by weight.
[0029]
As a specific method of reacting in the molten state, there is a method of mixing and reacting in the molten state. In order to mix and react in a molten state, a melt kneader generally used for thermoplastic resins can be used. A modification reaction takes place during melting in a melt kneader. Examples of the melt kneader include a uniaxial or multiaxial kneading extruder, a roll, and a Banbury mixer.
[0030]
When using the kneading extruder, for example, the components (1), (A1), (A2), (A3) and (A4) are mixed in advance with a blender or the like, and the resulting mixture is mixed with the kneading extruder. A method of feeding (feeding) at the upstream side of the mixture and reacting in a molten state is suitable.
[0031]
(2) Component (B)
In the present invention, the polyamide of component (B) refers to one having a -CONH- bond in the main chain and melted by heating. Typical examples include polyamide-4, polyamide-6, polyamide-6.6, polyamide-4.6, polyamide-12, polyamide-6.10, and other conventionally known aromatic diamines and aromatics. And crystalline or amorphous polyamide containing a monomer component such as an aromatic dicarboxylic acid. Preferred polyamides are polyamide-6, polyamide-6 · 6, and semi-aromatic polyamide, and may be a mixture of these and amorphous polyamide.
[0032]
The polyamide of component (B) is preferably one having a relative viscosity in the range of 2.1 to 3.5 measured at 25 ° C. in 98% by weight concentrated sulfuric acid. If the relative viscosity is less than 2.1, the finally obtained resin composition has poor rigidity, dimensional stability, impact resistance, appearance, etc. If it exceeds 3.5, the resin composition finally obtained Since moldability is inferior and the appearance of a molded product obtained from this resin composition is also deteriorated, neither is preferable. Further, the polyamide preferably has a terminal carboxylic acid content of 100 μeq / g or less, and preferably has a ratio of terminal carboxylic acid to terminal amine (terminal carboxylic acid / terminal amine) in the range of 0.8 to 4. When the ratio of the terminal carboxylic acid to the terminal amine exceeds 4, the compatibility between the component (A) and the component (B) decreases.
[0033]
(3) Component (C)
In the present invention, the inorganic filler of component (C) refers to an inorganic powder. The form of the powder may be any of spherical shape, cubic shape, granular shape, needle shape, plate shape, fiber shape and the like. The average particle size of these powders is 8 μm or less. When the average particle diameter exceeds 8 μm, the appearance of a molded product obtained from the resin composition is deteriorated, which is not preferable. Here, the average particle diameter means D50 measured by a liquid phase precipitation method by X-ray transmission. As an apparatus capable of such a measurement, a Sedigraph particle size analyzer (manufactured by Micromeritics Instruments, model 5100) can be mentioned.
[0034]
Specific examples of the component (C) include, for example, titanium oxide, zinc oxide, barium sulfate, silica, calcium carbonate, iron oxide, alumina, calcium titanate, aluminum hydroxide, magnesium hydroxide, calcium bicarbonate, magnesium carbonate, Calcium sulfate, sodium sulfate, calcium sulfite, magnesium silicate (talc), calcium silicate (wollastonite), clay, glass beads, glass powder, glass fiber, silica sand, silica, quartz powder, shirasu, diatomaceous earth, Examples include white carbon, iron powder, and aluminum powder. These inorganic fillers may be used alone or in combination of two or more.
[0035]
Among these, in order to improve the dimensional stability and rigidity of the finally obtained resin composition and obtain a good appearance, a plate shape, needle shape, and an average particle diameter of 0.1 to 5 μm, A fibrous material is preferable, and among these inorganic fillers, magnesium silicate (talc) and calcium silicate (wollastonite) are particularly preferable, and an average particle size of 0.2 to 3.5 μm or less is more preferable. They are magnesium silicate (talc) and calcium silicate (wollastonite).
[0036]
In the present invention, magnesium silicate (talc) means hydrous magnesium silicate, which is usually SiO. ₂ 58-66 wt%, MgO 28-35 wt%, H ₂ About 5% by weight of O is contained. Fe as other minor components ₂ O ₃ 0.03 to 1.2% by weight, Al ₂ O ₃ 0.05 to 1.5% by weight, CaO 0.05 to 1.2% by weight, K ₂ O is 0.2 wt% or less, Na ₂ O is contained at 0.2% by weight or less, and the specific gravity is about 2.7.
[0037]
In the present invention, calcium silicate (wollastonite) is a natural white mineral having acicular crystals, and the chemical formula is CaSiO. _Three Usually represented by SiO ₂ 50% by weight, CaO 47% by weight, other FeO _Three , Al ₂ O _Three And the specific gravity is 2.9. Such fibrous inorganic fillers mainly composed of calcium silicate are usually called wollastonite. It is commercially available as PH330 and PH450 from Kawatetsu Mining, and as Nigros 4 and Nigros 5 from Nyco, and those having an average aspect ratio of 3 or more are preferred.
[0038]
The inorganic filler may be left untreated, but for the purpose of increasing the affinity with the resin component or the interfacial bond strength, an inorganic surface treatment agent, a derivative such as a higher fatty acid or an ester salt thereof, a coupling agent, etc. What was processed by is preferable. When surface treatment is performed in combination with various surfactants such as nonionic, cationic and anionic types, and dispersing agents such as various resins, the viewpoint of improving mechanical strength and kneadability To preferred.
[0039]
(4) Other ingredients
The thermoplastic resin composition according to the present invention contains at least the above three components, but other various resin additives can be blended (contained) in addition to these components. Examples of various resin additives include heat stabilizers, antioxidants, weather resistance improvers, nucleating agents, foaming agents, flame retardants, impact resistance improvers, lubricants, plasticizers, fluidity improvers, dyes and pigments. , Organic fillers, reinforcing agents, dispersants and the like. As the impact resistance improver, rubbers such as hydrogenated block copolymers of unmodified vinyl aromatic compound polymer block A and conjugated diene compound polymer block B, and ethylene-α-olefin copolymers A state polymer. These rubber-like polymers are preferably blended (contained) in the range of 10:90 to 90:10 by weight ratio to the component (A).
[0040]
(5) Mixing ratio and mixing method of each component
The thermoplastic resin composition according to the present invention comprises at least a component (A) 3 to 60% by weight and a component (B) 40 to 97% by weight, and a resin comprising the component (A) and the component (B). The component (C) is further blended (included) in a proportion of 5 to 60 parts by weight with respect to 100 parts by weight of the total component. If the component (A) is less than 3% by weight in the ratio of the resin component to the component (A) and the component (B), the impact resistance and dimensional stability of the finally obtained resin composition are inferior, and 60% by weight. If it exceeds, the impact resistance and dimensional stability are lowered, and the fluidity is also lowered. The blending ratio of component (A) to component (B) is preferably component (A) / component (B) of 5 to 55/95 to 45, more preferably 10 to 50/90 to 50. is there.
[0041]
Further, when the blending ratio of the component (C) is less than 5 parts by weight with respect to 100 parts by weight of the total resin component composed of the component (A) and the component (B), the rigidity of the resin composition finally obtained is The effect of improving the dimensional stability is small, and if it exceeds 60 parts by weight, the impact resistance is lowered, which is not preferable. The blending ratio of component (C) is preferably 10 to 50 parts by weight, more preferably 15 to 45 parts by weight.
[0042]
The thermoplastic resin composition according to the present invention comprises at least the above components and ratios. The micro-form {fine texture of pellets of thermoplastic resin composition exhibiting particularly excellent impact resistance and dimensional stability (low linear expansion coefficient) and rigidity, or small pieces cut out from injection molded products , Morphology, etc.} were observed with a transmission electron microscope (TEM) and found to have a unique morphology. Peculiar micro-forms are small pieces from pellets or injection-molded products, for example, ultra-microtome (Leica, ULTRCUT CUT) equipped with a cryo device, using diamond knives, at a temperature of −100 ° C. and a thickness of 100 n ultra-thin. After cutting into sections and staining the surface of the cut pieces with osmium tetroxide and ruthenium tetroxide, they can be easily observed using a transmission electron microscope (for example, JEOL Ltd., model: JEM1200EXII type).
[0043]
After staining the surface of the small piece, when observed with a transmission electron microscope, among the resin components, component (A) is observed in the darkest color, and since component (C) contains more heavy atoms than the resin component A dark color is observed even without staining. Observation by this method and analysis of the particle shape and contour of the discontinuous phase (domain phase) using an image analyzer revealed that the following characteristics were exhibited. (1) From the transmission electron micrograph, component (A) is a discontinuous phase, component (B) is a continuous phase (matrix phase), and component (C) is mainly in the continuous phase of component (B). It exists.
[0044]
(2) Component (A) is present in the continuous phase of component (B) as particles having an uneven contour, and (3) The average particle size of the particles having an uneven contour is 3 μm. The following is preferable, and more preferable is 1 μm or less. Furthermore, (4) the interface between the continuous phase of component (B) and the discontinuous phase of component (A) forms irregularities corresponding to the particles having the irregular contour of component (A), and There is no gap.
[0045]
(5) An image of the uneven interface contour between component (A) and component (B) for the particle of component (A) that exhibits this contour and disperses as a discontinuous phase in component (B). It is read by a processing analysis device (for example, Spica, manufactured by Nippon Avionics Co., Ltd.), binarized and extracted, the total length of the concavo-convex contour of component (A) is measured, and this value is La.
When the boundary length of the interface (the overall length of the concave-convex contour) when smoothing the contour of the component (A) exhibiting the concave-convex shape is Lb, the ratio between the two (ratio of the interface peripheral length) (La / Lb) Has a special interface structure of 1.15 or more, particularly preferably 1.2 or more. In other words, the interface structure with severe irregularities having an interface perimeter ratio (La / Lb) of 1.15 or more, preferably 1.2 or more, absorbs an impact force from the outside to the resin composition and has an impact resistance. Is estimated to contribute to dimensional stability.
[0046]
In the present invention, the smoothing of the contour of the component (A) is to calculate the circumference (Lb) of the uneven interface contour 11 shown by a solid line in FIG. The particle of component (A) that exhibits the uneven interface contour shown by the solid line in FIG. 1 is subjected to 20 times of four connected expansions by an image processing analyzer, and then thinned to eliminate the unevenness of the interface contour and smoothing. The circumference 22 (Lb) after this is shown by a dotted line in FIG.
[0047]
In order to make the micro form {fine texture or morphology} of the thermoplastic resin composition according to the present invention specific as described above, it is preferable to use a melt mixing method. For example, (1) First, the component (A) is reacted in a molten state, and then the component (B) is introduced in the middle part of the kneading extruder to cause the component (A) and the component (B) to melt and react. Examples thereof include a method in which the component (C) is melt-mixed from the downstream part of the kneading extruder to obtain pellets of the thermoplastic resin composition.
[0048]
In addition, (2) Pelletized component (A) and component (B) are charged into a kneading extruder, the components (A) and (B) are melt-reacted, and the components ( Examples thereof include a method of melt-mixing C) and pelletizing the thermoplastic resin composition. Furthermore, (3) the pelletized component (A) and the pellet-shaped component (B) are put into a kneading extruder, kneaded in a molten state and pelletized, and the resulting pellet is mixed with the component (C). There is also a method in which the mixture is put into a kneading extruder and melt-mixed to form a pellet of a thermoplastic resin composition.
[0049]
Further, in the method for obtaining a modified product of the component (A) described above, only when the modified product is used by reacting the components (A1), (A2), (A3) and (A4) in the molten state at the same time, A thermoplastic resin composition having a special interface structure in which the interface perimeter length ratio (La / Lb) is 1.15 or more can be obtained. The modified product obtained by reacting (A1), (A3) and (A4) in a molten state and the modified product obtained by reacting (A2), (A3) and (A4) in a molten state are mixed, and the above-mentioned interface is mixed. Since a thermoplastic resin composition having a special interface structure with a circumference ratio (La / Lb) of 1.15 or more cannot be obtained, the order of mixing (addition) is extremely important.
[0050]
In addition, in the case where the component (A), the component (B), and the component (C) are melt-mixed, the components (A) and the component (B) are melt-reacted in advance, and then the component (C) is melt-mixed. Only when it is possible to obtain a thermoplastic resin composition having a special interface structure in which the ratio of the interface perimeter (La / Lb) is 1.15 or more, the impact resistance, dimensional stability, and rigidity are improved. Since an excellent thermoplastic resin composition is obtained, it is necessary to pay attention to the mixing (addition) order.
[0051]
(6) Use of thermoplastic resin composition
The method for producing a molded product from the thermoplastic resin composition according to the present invention is not particularly limited, and is a molding method generally employed for thermoplastic resins, that is, an injection molding method, a hollow molding method, an extrusion molding method. A sheet molding method, a thermoforming method, a rotational molding method, a lamination molding method, a press molding method and the like can be employed. The thermoplastic resin composition of the present invention can be used in a wide range of fields as a raw material for producing electrical equipment parts, electronic equipment parts, automobile parts and the like. It is particularly useful as a raw material for manufacturing automobile exterior parts.
[0052]
【Example】
EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these ranges. The raw materials used in the examples and comparative examples have the following physical properties and characteristics. The raw materials used in the examples and comparative examples have the following physical properties and characteristics. In the following examples and comparative examples, the blending amount means parts by weight.
[0053]
Ingredient (A):
(A1) PPE: polyphenylene ether (poly-2,6-dimethyl-1,4-phenylene ether manufactured by Mitsubishi Engineering Plastics Co., Ltd., having an intrinsic viscosity of 0.40 dl / g measured in chloroform at a temperature of 30 ° C. belongs to.
(A2) SEBS-1: Styrene content 29% by weight, molecular weight 80,000, ABA type styrene-ethylene / butylene-styrene block copolymer (manufactured by Shell Chemical Co., Ltd., trade name: Clayton) G1650).
[0054]
(A2) SEBS-2: A styrene content of 33% by weight, a molecular weight of 200,000, and an ABA type styrene-ethylene / butylene-styrene block copolymer (manufactured by Shell Chemical Co., Ltd., trade name: Kraton G1651) ).
(A2) SEBS-3: Styrene content of 29% by weight, molecular weight of 49,000, ABA type styrene-ethylene / butylene-styrene block copolymer (manufactured by Shell Chemical Co., Ltd., trade name: Kraton G1652) ).
(A3) Unsaturated acid anhydride and / or unsaturated acid: maleic anhydride (trade name: maleic anhydride, manufactured by Mitsubishi Chemical Corporation).
[0055]
(A4) Parkadox 14: 1, 3-bis (2-t-butylperoxyisopropyl) benzene (manufactured by Kayaku Akzo Co., Ltd., trade name: Parkadox 14, decomposition temperature at 121 ° C. after 10 hours of half-life) It is.
(A4) perhexa 25B: 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (manufactured by NOF Corporation, trade name: perhexa 25B, decomposition temperature after 10 hours of half-life is 118 ° C.) .
(A5) EBR: ethylene-butene copolymer (manufactured by Mitsui Petrochemical Co., Ltd., trade name: Toughmer A-4085).
[0056]
Component (B) (polyamide):
(B-1): Polyamide 6 (Mitsubishi Engineering Plastics, trade name: Novamid 1010J, 98% concentrated sulfuric acid in a concentrated sulfuric acid at 23 ° C. and a relative viscosity of 2.5 dl / g, terminal carboxylic acid / terminal amine The ratio is 2.6).
(B-2): Polyamide 6 (manufactured by Kanebo Co., Ltd., trade name: Kanebo nylon MC100L, in 98% concentrated sulfuric acid, the relative viscosity measured at 23 ° C. is 2.2 dl / g, and the terminal carboxylic acid / terminal amine ratio is 2.3).
(B-3): Polyamide 6 (manufactured by Mitsubishi Engineering Plastics, trade name: Novamid 1005J, relative viscosity measured at 23 ° C. in 98% concentrated sulfuric acid at 2.0 dl / g, terminal carboxylic acid / terminal amine The ratio is 4.9).
(B-4): Polyamide 6 (manufactured by Kanebo Co., Ltd., trade name: Kanebo Nylon MC112L, in 98% concentrated sulfuric acid, the relative viscosity measured at 23 ° C. is 2.7 dl / g, and the terminal carboxylic acid / terminal amine ratio is 1.3).
[0057]
Ingredient (C) (inorganic filler):
(C-1): Magnesium silicate (talc) (manufactured by Matsumura Sangyo, trade name: high filler # 5000PJ, average particle size: 1.8 μm).
(C-2): Calcium silicate (wollastonite) (manufactured by Kawatetsu Mining Co., Ltd., PH450, average particle size: 3.8 μm).
[0058]
[Adjustment of component (A)]
The above components (A1), (A2), (A3), and (A4) were weighed in the proportions shown in Table 1 and mixed uniformly with a Henschel mixer, and then a twin screw extruder (screw diameter 30 mm, L / D = 42), the mixture was melted and reacted under the conditions of a cylinder temperature of 240 ° C. and a screw rotation speed of 400 rpm, and pelletized to obtain components (A-1) to (A-11).
[0059]
[Table 1]

[0060]
[Preparation of test piece]
The resin composition was molded using an injection molding machine (Toshiba Machine Co., Ltd., model: IS150) under the conditions of a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C., and an ASTM test piece, diameter 100 mm × thickness 3 mm A disk-shaped specimen was prepared.
[0061]
[Evaluation methods]
(1) Micromorphological observation: From the above disk-shaped specimen, an ultra microtome (Leica, ULTRACUT CUT) equipped with a cryo device (REICHERT-NSSEI FCS), using a diamond knife and thick at -100 ° C A 100 nm thick ultrathin section was cut out. After the sliced section is stained with osmium tetroxide and ruthenium tetroxide, the micromorphology (dispersion state, interface perimeter length ratio) is observed using a transmission electron microscope (manufactured by JEOL Ltd., model: JEM1200EXII type). did. Next, the image obtained by tracing the interface of the particles is read by an image processing analyzer (manufactured by Nippon Avionics, apparatus name: Spica), the interface outline is binarized and extracted, and the circumference (Lb) after smoothing is calculated. Then, the interface perimeter length ratio (La / Lb) was measured. This operation was measured for 20 or more discontinuous phases, and the average value was calculated. The apparent average diameter (Lb) of the particles having an uneven contour was calculated by repeating the thinning process after repeating the 4-connected expansion 20 times with an image processing analyzer.
[0062]
(2) Fluidity (MFR): Measured in accordance with JIS K7210 under conditions of a temperature of 280 ° C. and a load of 5 kg.
(3) Flexural modulus: measured in accordance with ASTM D790.
(4) Impact resistance (Izod impact strength): Measured with a test piece having a thickness of 3.2 mm and a notch according to ASTM D256.
[0063]
(5) Dimensional stability (linear expansion coefficient): The linear expansion coefficient was measured in accordance with ASTM D696. However, the measurement temperature range was 23 to 80 ° C.
(6) Appearance: Visually observe the surface appearance of the disk-shaped molded product, ◎ if the image of the fluorescent lamp is very clear, ◎ if it is clear, ○ if it is slightly fluctuated, △ if it is fluctuated It evaluated as x.
[0064]
[Example 1 and Comparative Examples 1 to 2]
Ingredients (A) and (B) were weighed in the proportions shown in Table 2, and mixed uniformly with a tumbler mixer. Using this mixture, a twin screw extruder (manufactured by Nippon Steel Works, TEX30XCT, L / D = 42, barrel number 12), cylinder temperature 230 ° C., screw rotation speed 400 rpm, barrel 1 of the twin screw extruder The resin composition was prepared by feeding (feeding) the mixture and allowing it to melt and then adding the component (C) from the barrel 5 of the twin-screw extruder and melt-kneading. Test pieces were prepared from the obtained resin composition by the injection molding method as described above, and various physical properties of the obtained test pieces were measured by the method described above. The measurement results are shown in Table-2.
[0065]
[Comparative Example 3]
Example in which component (C) was mixed uniformly with component (A) and component (B) with a tumbler mixer and charged into a twin-screw extruder (same as used in Example 1) from barrel 1 A resin composition was prepared in the same procedure as in 1. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 1 and the physical properties were measured. The measurement results are shown in Table 2.
[0066]
[Example 2 and Comparative Example 4]
A resin composition was prepared in the same manner as in the example described in Example 1, except that the polyamide was changed to one having a different relative viscosity. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 1 and the physical properties were measured. The measurement results are shown in Table 2.
[0067]
[Example 3, Comparative Example 5, and Comparative Example 6]
A resin composition was prepared in the same manner as in the example described in Example 1, except that the weight ratio of PPE and SEBS and the molecular weight of SEBS were changed. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 1 and the physical properties were measured. The measurement results are shown in Table 2.
[0068]
[Table 2]

[0069]
From Table-1 and Table-2, the following becomes clear.
(1) The resin composition of Example 1 has a special interface structure in which the value of (La / Lb) is as large as 1.45, and the interface between the continuous phase and the discontinuous phase exhibits an uneven contour, Excellent balance of impact resistance, dimensional characteristics and rigidity.
(2) In contrast, the resin composition of Comparative Example 1 containing (A2) in which no radical generator was added as component (A) had a small (La / Lb) value of 1.03. It differs from the resin composition of Example 1 in the contour of dispersed particles of component (A), and is inferior in impact resistance and dimensional stability.
(3) Also, the resin composition of Comparative Example 2 in which EBR is blended instead of SEBS-1 is different from the resin composition of Example 1 in the profile of dispersed particles and is inferior in dimensional stability.
(4) Furthermore, the value of (La / Lb) is 1 in the resin composition of Comparative Example 3 in which component (A), component (B), and component (C) are all put into a kneading extruder and melt-kneaded. .13, which is different from the resin composition of Example 1, and has poor dimensional stability and rigidity.
[0070]
(5) Compounding polyamide with a relative viscosity of 2.2 The resin composition of Example 2 has a large (La / Lb) value of 1.42, and, as in Example 1, the continuous phase and discontinuity It has a special interface structure in which the interface with the phase has an uneven contour, and is excellent in the balance between impact resistance, dimensional characteristics, and rigidity.
(6) On the other hand, the composition of Comparative Example 4 in which the example of polyamide is 2.0 has a small (La / Lb) value of 1.10, which is different from those of Examples 1 and 2. Dispersion particles have different contours and are inferior in impact resistance, dimensional stability and rigidity.
(7) As the component (A), the resin composition of Example 3 blended with (A4) in which the weight ratio of PPE, SEBS-, and 1 is 50:50 has a (La / Lb) value of 1. It has a special interface structure in which the interface between the continuous phase and the discontinuous phase has an irregular contour, and is excellent in balance between impact resistance, dimensional stability and rigidity.
(8) On the other hand, as component (A), in Comparative Example 5 in which the weight ratio of PPE to SEBS was 70:30, and (A2) constituting component (A) was SEBS-2 (molecular weight The resin composition of Comparative Example 6, which was a large one, had a (La / Lb) value as small as 1.05 (Comparative Example 5) and 1.06 (Comparative Example 6). No. 3 resin composition has a different dispersed particle profile and is inferior in dimensional stability and rigidity.
[0071]
[Examples 4 to 6, Comparative Example 7, and Comparative Example 8]
Ingredients (A) and (B) were weighed in the proportions shown in Table 3, and uniformly mixed by a tumbler mixer. Using this twin screw extruder (same as that used in Example 1), this mixture was charged into the twin screw extruder from barrel 1 under the conditions of a cylinder temperature of 230 ° C. and a screw rotation speed of 400 rpm to cause a melt reaction. Further, the component (C) was introduced from the barrel 5 into a twin screw extruder, and melt kneaded to prepare a resin composition. Test pieces were prepared from the obtained resin composition with an injection molding machine as described above, and various physical properties of the obtained test pieces were measured by the methods described above. The measurement results are shown in Table 2.
[0072]
[Comparative Example 9]
In the example described in Example 4, component (C) was mixed uniformly with component (A) and component (B) with a tumbler mixer, and the resulting mixture was charged into a twin-screw extruder from barrel 1. A resin composition was prepared in the same procedure as in Example 4. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 4 and the physical properties were measured. The measurement results are shown in Table 3.
[0073]
[Example 7]
In the example described in Example 1, a resin composition was prepared in the same manner as in Example 1 except that the amount of component (C) was changed. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 1 and the physical properties were measured. The measurement results are shown in Table 3.
[0074]
[Example 8]
A resin composition was prepared in the same manner as in the example described in Example 4, except that the type of component (C) was changed. With respect to the obtained resin composition, test pieces were prepared in the same procedure as in Example 4 and the physical properties were measured. The measurement results are shown in Table 3.
[0075]
[Table 3]

[0076]
From Table-1 and Table-3, the following becomes clear.
(1) The resin compositions of Examples 4 to 6 have a large (La / Lb) value of 1.35, and a special interface structure in which the interface between the continuous phase and the discontinuous phase exhibits an uneven contour. It has excellent balance between impact resistance, dimensional characteristics and rigidity.
(2) In contrast, the resin composition of Comparative Example 7 to which no radical generator was added had a different interface structure from the composition of Example 4, and was inferior in impact resistance and dimensional stability. The resin composition of Comparative Example 8 containing EBR as A2) also has a different interface structure from the composition of Example 4 and is inferior in dimensional stability.
(3) The resin composition of Comparative Example 9 in which component (A), component (B), and component (C) are all put into a kneading extruder and melt-kneaded also has a (La / Lb) value of 1. The interface structure is different from that of the resin composition of Example 4 and is inferior in dimensional stability and rigidity.
(4) The resin composition of Example 7 and Example 8 is a special interface in which the interface between the continuous phase and the discontinuous phase exhibits a concavo-convex contour, like the resin compositions of Example 1 and Example 4. It has a structure and excellent balance between impact resistance, dimensional characteristics, and rigidity.
[0077]
【The invention's effect】
The thermoplastic resin composition according to the present invention is as described above in detail, and has the following particularly excellent effects, and its industrial utility value is extremely large.
1. The thermoplastic resin composition according to the present invention has high melt fluidity and excellent processability and is easy to mold.
2. The thermoplastic resin composition according to the present invention is excellent in impact resistance, dimensional stability and rigidity, and these physical properties are preferably balanced.
3. Since the thermoplastic resin composition according to the present invention is excellent in dimensional stability,
Even when used in combination with metal parts, problems such as dimensional differences and poor meshing hardly occur.
4). From the thermoplastic resin composition according to the present invention, a molded product having excellent surface appearance, paint adhesion, and the like can be produced. Therefore, as a material for manufacturing electrical equipment parts, electronic equipment parts, and automobile parts, a wide range of fields. Especially available. It is useful as a material for manufacturing automobile exterior parts.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating smoothing.
[Explanation of symbols]
11: Concave and convex outline of component (A)
22: Circumference after smoothing

Claims (1)

In producing a thermoplastic resin composition pellet or injection-molded product containing the following components (A), (B) and (C), first, the components (A) and (B) are prepared in advance. When melt reaction is performed, then component (C) is melt-mixed, and when the micro form of the obtained thermoplastic resin composition pellets or injection-molded product is observed with an electron microscope, component (B) forms a continuous phase, In the continuous phase of component (B), component (A) is present in a discontinuous phase by being dispersed in particles having an uneven contour, and component (A) and component (B) When the interface perimeter of the contour exhibiting the concavo-convex shape is La and the interface perimeter when smoothing the contour exhibiting the concavo-convex shape is Lb, the ratio (La / Lb) between the two is 1.15 or more. Characterized by thermoplastic resin composition pellets or injection molded articles Manufacturing method.
Component (A): (A1) 0 to 60% by weight of polyphenylene ether,
(A2) The vinyl aromatic compound polymer block A and the conjugated diene compound polymer block B block copolymer hydrogenated with 100 to 100 parts by weight of the hydrogenated product, and (A3) unsaturated acid 0.1 to 5 parts by weight of anhydride and / or unsaturated acid, 3 to 60% by weight of a modified product obtained by reacting 0.03 to 3 parts by weight of (A4) radical generator in a molten state, and
Component (B): 100 parts by weight of a resin component comprising 40 to 97% by weight of polyamide,
Component (C): It contains 5 to 60 parts by weight of an inorganic filler having an average particle size of 8 μm or less.

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