JP3849809B2

JP3849809B2 - Novel polymer blend fiber and process for producing the same

Info

Publication number: JP3849809B2
Application number: JP21334295A
Authority: JP
Inventors: 哲史岡; 誠喜西原; 浩安田
Original assignee: Toyobo Co Ltd
Current assignee: Toyobo Co Ltd
Priority date: 1994-08-24
Filing date: 1995-08-22
Publication date: 2006-11-22
Anticipated expiration: 2015-08-22
Also published as: JPH08113829A

Description

【０００１】
【発明の属する技術分野】
本発明は，新規な相分離形態を有し，例えば風合い，染色性，軽量・保温性，吸水・吸湿性，耐熱性，撥水・撥油性等の特徴を付与した合成繊維として多方面へ利用できるポリマ−ブレンド繊維およびその製造法に関するものである。
【０００２】
【従来の技術】
ポリマ−ブレンドによる混合紡糸は，合成繊維の改質手段として，例えば染色性の向上，吸湿性の調節，比重の調節，橋かけ効果，粘弾性的性質の改善，風合い感触の向上等を目的に広範囲への応用が試みられている。この際，非相溶系ポリマ−ブレンドを用いた溶融紡糸法による場合が主流である。
しかしながら，互いに相溶しない２種以上のポリマ−ブレンドを溶融紡糸するする場合，（１）ポリマ−の混合が困難であったり，あるいは紡糸原液が不安定となり，脱混合を起こす場合が多い，（２）曳糸性が不良なため紡糸速度が上げられず生産性に劣る，（３）得られた繊維の性質が変動し易い等の問題点があった。
【０００３】
これらの欠点を改良するため，分散ポリマ−と相溶化剤を溶融状態であらかじめ混練りし，次いで繊維形成性ポリマ−を溶融状態で混合した後溶融紡糸する方法（特開平４−２０９８２４号公報）や，海島構造の島成分に繊維形成性の熱可塑性樹脂を用い，製糸性を改良しながらブレンドポリマ−の特徴を活かす方法（特開平６−２２６７号公報）が開示されている。
【０００４】
しかしながら，本質的に相溶性のないポリマ−ブレンド系を用いる限り，ノズル通過時の剪断変形あるいは巻取り時の伸長変形を受ける際に分散相のサイズが変動，不均一化してしまい上記問題点を充分に改良することはできない。さらに，かかる相溶化剤は総じて高価であるため経済的に好ましいとは言えなかった。以上のように，非相溶ポリマ−ブレンド繊維は広範囲への応用が期待されるにもかかわらず，上記問題点が充分に解決されていないため，実用化の例が極めて少ないのが現状である。
【０００５】
【発明が解決しようとする課題】
本発明は，上記従来技術における問題点に着目してなされたものである。すなわち，本発明は安定な紡糸工程により，繊維の相分離構造を多様に，しかも再現性良く制御することを目的とするものである。また，分散相のサイズが小さく，かつサイズ分布の小さい形態を付与することにより，例えば，相分離繊維でありながら力学特性に優れるものや，分散相を例えば撥水・撥油等の機能を付与するための効果的な反応基点としたものや，さらには分散相のみを抽出することにより，軽量・保温性，ドライタッチ，深色鮮明性，あるいは吸水・吸湿性等の特徴を備えた繊維を提供することを目的としている。
【０００６】
【課題を解決するための手段】
上記課題を解決するための手段、すなわち，本発明は，２成分からなるポリマ−ブレンド繊維であり，繊維横断面内において，一成分が円換算直径で０．００１〜０．４ミクロンのサイズに分散，相分離していることを特徴とする新規なポリマーブレンド繊維であり、更には、２成分からなるポリマーブレンド繊維であり、繊維の縦、横断面において、一成分が分散、相分離しており、相分離した分散相の，繊維横断面内における円換算直径（Ａ）および繊維縦断面内における円換算直径（Ｂ）の比（Ｐ）が下記（１）式の通り，２．０以下であることを特徴とする新規なポリマーブレンド繊維であり、
Ｐ＝Ｂ／Ａ≦２．０（１）
【０００７】
相分離した分散相の，繊維横断面内における円換算直径（Ａ）および繊維縦断面内における円換算直径（Ｂ）の比（Ｐ）が下記（１）式の通り，２．０以下である請求項１記載の新規なポリマーブレンド繊維であり、
Ｐ＝Ｂ／Ａ≦２．０（１）
２成分からなるポリマーブレンド繊維であり、繊維の縦、横断面において、一成分が分散、相分離しており相分離した分散相が，繊維軸方向及び／又は断面方向に連通した形態を有する相分離構造である新規なポリマーブレンド繊維であり、相分離した分散相の繊維横断面における円換算直径が０．００５〜０．１ミクロンである新規なポリマーブレンド繊維であり、相分離した分散相の繊維横断面における円換算直径が０．０１〜０．１ミクロンである新規なポリマーブレンド繊維であり、
【０００８】
相分離構造が，連続相および／または分散相からなり，繊維横断面より任意に選んだ２０の分散相の平均面積（Ｘ）が０．１５平方ミクロン以下で，かつそのばらつきを表す指標Ｙが２．０以下である新規なポリマーブレンド繊維であり、
Ｙ＝Ｒ／Ｘ（Ｒ＝Ｘmax−Ｘmini）
（但し，Ｘは，任意に選んだ２０個の分散相の平均面積。Ｘmaxは，任意に選んだ２０個の分散相のうち，面積の最も大きいものから３つの平均値。Ｘminiは，任意に選んだ２０個の分散相のうち，面積の最も小さいものから３つの平均値。）
【０００９】
円換算直径で０．００１〜５ミクロンの微小空洞が無数にあり，かつそれぞれが互いに連結した海綿状の構造を有する繊維，および（９）ポリマーブレンドが，下記（２）式で表される重合度の比率が５０以下のポリマーブレンドである新規なポリマ−ブレンド繊維であり、
Ｎ＝ｎ１／ｎ２（２）
（但し，ｎ１はポリマ−ブレンド成分の中で重合度の大きい方のポリマ−の重合度，ｎ２はポリマ−ブレンド成分の中で重合度の小さい方のポリマ−の重合度。）２成分のうち少なくとも１成分が結晶性ポリマーである新規なポリマ−ブレンド繊維であり、ポリマ−ブレンドがポリスチレンとポリ−ε−カプロラクトン樹脂のブレンドである新規なポリマ−ブレンド繊維であり、
【００１０】
ポリマーブレンドが下記条件満足するＣ，Ｄ二種のポリマーからなる新規なポリマーブレンド繊維であり、ここでＣは、モノマーユニットａ，ｂからなる重合度５０以上の共重合体である。Ｄはホモポリマーであっても共重合体であっても良く，かつＣを構成するモノマーユニットａのみからなる重合度５０以上のホモポリマーとのブレンドにおいては完全相溶系であり，かつＣを構成するモノマーユニットｂのみからなる重合度５０以上のホモポリマーとのブレンドにおいては非相溶系である。
【００１１】
共重合体（Ｃ）を構成するモノマーユニットの一方の成分がエチレンテレフタレ−トであることを特徴とする新規なポリマーブレンド繊維であり、Ｃがポリマ−ブレンドがエチレンテレフタレ−トとエチレンナフタレ−トの共重合体であり，かつＤがポリエ−テルイミド樹脂であることを特徴とする新規なポリマ−ブレンド繊維であり、
【００１２】
エチレンテレフタレ−トとエチレンナフタレ−トの共重合割合が，エチレンテレフタレ−ト単位が９９〜５０モルに対してエチレンナフタレ−ト単位が１〜５０モルである新規なポリマ−ブレンド繊維であり、ポリエ−テルイミド樹脂が下記一般式化２で示される新規なポリマ−ブレンド繊維であり、
【化２】

（式中，Ｒ１は炭素原子数６〜３０の二価の芳香族有機基，Ｒ２は炭素原子数６〜３０の二価の芳香族有機基，炭素原子数２〜２０のアルキレン基もしくはシクロアルキレン基または炭素原子数２〜８のアルキレン基で連鎖停止されたポリオルガノシロキサン基を表す）
【００１３】
２成分からなる部分相溶系ポリマ−ブレンドを用いて相溶状態にして溶融紡糸し，紡出後の工程で物理的あるいは化学的手段により相分離構造を発現させることを特徴とする新規なポリマ−ブレンド繊維の製造法であり、ポリマ−ブレンドが，上限臨界共溶温度型の相図を有する新規なポリマ−ブレンド繊維の製造法であり、相分離構造を発現させる工程において，ガラス転移温度以上，バイノーダル温度以下で熱処理することを特徴とする新規なポリマーブレンド繊維の製造法であり、相分離構造を発現させる工程において，スピノーダル温度以上，バイノーダル温度以下で熱処理することを特徴とする新規なポリマーブレンド繊維の製造法であり、２成分のうち少なくとも１成分が結晶性ポリマ−である新規なポリマ−ブレンド繊維の製造法であり、紡出後の工程が，紡糸第一引き取りロール間である新規なポリマーブレンド繊維の製造法であり、紡出後の工程が，延伸工程である新規なポリマーブレンド繊維の製造法であり、紡出後の工程が，織物の精錬又は染色工程である新規なポリマーブレンド繊維の製造法であり、紡出後の工程で相分離構造を発現させた後，アルカリ減量処理する新規なポリマーブレンド繊維の製造法である。
【００１４】
以下，本発明の詳細を記述する。本発明の要点は，特定の温度域で互いに相溶する部分相溶系のポリマ−ブレンドを相溶状態でノズルより押し出すことにより，従来から試みられている非相溶ポリマ−ブレンドの溶融紡糸時における紡糸不安定性および繊維特性の変動等の欠点を改善し，かつ部分相溶系ポリマ−ブレンドの特性を利用し，相溶状態から非相溶状態へ変化する環境を与える工程を経ることにより，多様，かつ従来にない形態を付与することである。
【００１５】
本発明でいう相溶状態とは，分子レベルで均一に混合している状態のことであり，具体的には０．００１ミクロン以上の相構造を形成していない状態のことを言う。また，非相溶状態とは，相溶状態ではない場合，すなわち０．００１ミクロン以上の相構造を形成している状態のことを言う。相溶状態か否かを判断するには，例えばPolymer Alloys and Blends ,Leszek A Utracki,Hanser Publishers,Munich Vienna New York,P64.に述べられている通り，電子顕微鏡，示唆走査熱量計（ＤＳＣ），その他種々の手法によることができる。また，本発明でいう部分相溶系ポリマ−とは，実用的に選択できる温度および／またはポリマーブレンドを構成する２種類のポリマーの混合比を変更することにより相溶状態および非相溶状態の両方の分散状態をとり得るポリマ−ブレンドの組み合わせのことを，完全相溶系ポリマ−とは，実用的に選択できる温度および／またはポリマーブレンドを構成する２種類のポリマーの混合比によらず相溶状態であるポリマ−ブレンドの組み合わせのことを，非相溶系ポリマーとは，実用的に選択できる温度および／またはポリマーブレンドを構成する２種類のポリマーの混合比によらず非相溶状態であるポリマ−ブレンドの組み合わせのことを言う。ここで，実用的に選択できる温度とは，ポリマーブレンドのガラス転移温度（ガラス転移温度を複数有する場合は，その中で最も低いガラス転移温度）以上，ポリマーブレンドの分解開始温度以下を示す。
すなわち，部分相溶系，完全相溶系，非相溶系であるポリマーブレンドの相溶状態を例えば図１〜５の通りに表すことができる。
図１〜５は、本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図であり、図６〜９は、本発明でいう海島構図の繊維を横断面から観察した例を示す図であり、図１０は、本発明でいう変調構造の円換算直径Ｄの求め方を示す図であり、図１〜５におけるφはＡ成分の重量分率を示し、斜線部は二相領域を示し、斜線部以外は一相領域を示し、いずれの図においても温度の下限はポリマーブレンドのガラス転移温度（ガラス転移温度が２以上存在する場合は、その中で最も低いガラス転移温度）、上限は、ポリマーブレンドが分解し始める温度とする。
【００１６】
また，本発明でいう相分離構造とは，０．００１ミクロン以上の不均一な相構造を形成している構造のことをいい，さらに本発明では図６〜９に示す通り，一方の成分が他方の成分と独立した島状のドメインを形成している構造を海島構造（Ａ），両方の成分が互いに独立しておらず，３次元的に連結している構造を変調構造（Ｂ）と定義する。さらに，海島構造の島成分を抽出等により実質的に除去した構造を微多孔，変調構造の一方の成分を抽出等により実質的に除去した構造を海綿状の構造と定義する。
【００１７】
上述の如く，本発明で提供し得る繊維内の微細構造は，従来から試みられている非相溶系のポリマ−ブレンド繊維の構造とは大きく異なる。例えば，従来からの非相溶系のブレンド紡糸では，混合比の少ない成分がドメインを形成し，いわゆる海島構造を形成する。このドメインのサイズは，紡糸前の段階において微小・均一であっても，ノズル通過時のせん断変形あるいは巻き取り時の伸長変形により肥大化・不均一化するため，繊維横断面における円換算直径Ｄが０．４ミクロンより大きく，しかも，ばらつきの指標Ｙが２．０より大きかった（ここでいう，円換算直径Ｄおよびばらつきの指標Ｙは，後述の方法により求めたものである。Ｙは，分散相の面積が完全に均一である場合，１となる）。このように，Ｄが０．４ミクロンを越えるものは，単一成分からなる合成繊維と比較し，強度等の力学特性において劣ったり，分散相となる第２成分の特徴を付与するには，相当量の混合比が必要であり，コストが大幅に増大する。さらには，分散相のピッチが大きいため，例えば吸水・吸湿性，撥水・溌油性，深色鮮明性，軽量・保温性等の特徴を効果的に付与できない，等の問題点があった。また，ばらつきの指標Ｙが２．０を越えるものは，繊維物性の変動が大きいため，強度が劣る，あるいは染色斑が生じる，といった問題点があった。これに対し，当技術によれば，円換算直径が０．００１≦Ｄ≦０．４ミクロン，ばらつきの指標がＹ≦２．０である微小かつ均一な分散サイズの形態を付与することができる。このようにＤ≦０．４ミクロン，かつＹ≦２．０であるものは，相分離繊維でありながら，力学特性に優れる，分散相を，例えば，撥水・溌油性等の相反する機能を付与するための効果的な反応基点とすることができる，分散相のみを抽出することにより，軽量・保温性，ドライタッチ，深色鮮明性，あるいは吸水・吸湿性等の特徴を付与することができる，等の点で従来の非相溶ブレンド繊維では到底到達し得なかった性能あるいは特徴を有する。
【００１８】
また，従来からの非相溶ブレンド繊維では，繊維中のポリマー分散状態が，用いるポリマーブレンドの種類および混合比によりほぼ決定されるため，付与することのできる特徴が限定されたものであった。これに対し，本発明によれば単一複合素材を用いて，相分離条件を変更することにより，分散相のサイズ・形態において多種多様の繊維を提供することができる。例えば，スピノーダル温度以上，バイノーダル温度以下で短時間処理したもの，あるいは長時間処理したもの，さらには，ガラス転移温度以上，スピノーダル温度以下で熱処理した場合では，得られる形態およびサイズが大きく異なり，かつ従来にない新規な構造を得ることができる（本発明でいう，スピノーダル温度，バイノーダル温度とは，公知の通り，以下のことを意味する。すなわち、スピノーダル温度とは、「スピノーダル分解機構」により相分離する温度と「核生成および成長機構」により相分離する温度の境界のことである。また、バイノーダル温度とは、系が相溶する温度と相分離する温度の境界のことである。これらの詳細な説明は、例えば，Polymer Alloys and Blends ,Leszek A Utracki,Hanser Publishers,Munich Vienna New York,P32. 等に示されている。）中でも，スピノーダル温度以上，バイノーダル温度以下で短時間処理した場合に生じる，分散相が繊維軸方向および／または断面方向に連通した変調構造は，非相溶ポリマ−により形成される海島構造では到底達し得ない効果が期待できる。例えば，上記形態では，２成分とも連続相となり，かつ界面の厚みが大きいため，耐熱性ポリマーを一方の成分に用いることにより，ブレンド繊維の耐熱性を飛躍的に向上することができる。さらに，一方の成分のみを抽出することにより海綿状の繊維を得ることもできる。このようにして得られた海綿状繊維は，無数の微小空洞が互いに連通しているため，従来素材では到底到達し得なかった吸水・吸湿性等の性能を付与することができる。
【００１９】
さらに，従来からの非相溶ブレンド繊維では，紡糸あるいは延伸時のドラフトにより，分散相の形態が繊維軸に沿って極度に伸長するため，繊維横断面および縦断面の円換算直径の比率が２を越えるものしか造り得なかった。このような，形態により，深色鮮明性やタッチの面での特徴を付与しても大きな効果は期待できない。これに対し，本発明では，相分離構造を発現する工程が，紡出以降であるため，繊維横断面および縦断面の円換算直径の比率がほぼ１である分散相の形態を付与することも可能である。このような形態は，分散相を抽出することにより表面に微多孔を有する繊維とすることができ，これまでにないタッチあるいは，深色鮮明性等の特徴を付与することができる。
【００２０】
また，従来からの非相溶ブレンド繊維は，繊維横断面より観察される分散相のサイズが平均面積Ｘが０．１５平方ミクロンより大きく，かつそのばらつきを表す指標Ｙが２．０を越えるため，品質が変動したり，未延伸糸の段階で前記の如き分散状態であるものは，延伸時にボイド等の欠陥を生じる，等の問題点があった。これに対し本発明では，分散相のサイズが微細かつ均一であるため，品質変動が少なく，かつ未延伸糸の状態で相分離構造を付与しても容易に延伸することができる。特に，相分離構造が，連続相および／または分散相からなり，繊維横断面より任意に選んだ２０個の分散相の平均面積Ｘが０．１５平方ミクロン以下で，かつそのばらつきを表す指標Ｙが２．０以下である場合，品質の安定性および延伸性の面で非相溶ポリマーブレンド繊維のそれより著しく優れたものとなる。また，延伸糸において分散相サイズのばらつきが少ないものは，従来からの非相溶ブレンド繊維に対し，特に強度等の力学的特性の面で有利である。
さらに，繊維形成後も織物の精錬又は染色工程時の熱処理等により相分離構造の形態およびサイズを任意に制御できる，あるいは易アルカリ減量成分のエッチングによる微多孔化や海綿状化，等も可能であるため広範囲な要求物性に応じることができる。
【００２１】
本発明で述べるポリマ−ブレンドとは，以下の関係にあるポリマ−重合度の比率Ｎが５０以下であり，かつ部分相溶系であるものが望ましい。
Ｎ＝ｎ１／ｎ２（但し，ｎ１はポリマ−ブレンド成分の中で重合度の大きい方のポリマ−の重合度，ｎ２はポリマ−ブレンド成分の中で重合度の小さい方のポリマ−の重合度。）
上述の重合度は，ポリマ−ブレンドを構成する各成分をポリマ−ブレンド中，少なくとも一方の成分が可溶である溶剤を用いた抽出操作等で単離し，得られた各成分の分子量を測定することにより算出することができる。
Ｎが５０を越えると，低重合度成分が実質上高重合度成分の溶剤として作用し，相分離速度が極度に速くなるため，相分離構造を任意に，しかも再現性良く制御することが困難となる。また，低分子量成分が繊維に残留し難く，長期残存性に劣るという欠点もある。従って，この比率Ｎは，好ましくは２０以下，さらに好ましくは１０以下であることが望ましい。
【００２２】
また，ポリマ−ブレンドの組み合わせは，部分相溶系であれば特に限定しないが，（１）紡糸時の溶融押し出し後における気体あるいは液体による冷却過程のみで相分離構造を発現し得る，また（２）繊維形状を保持したまま，加熱処理により相分離構造を発現し得る上限臨界共溶温度型の相図を有するポリマ−の組み合わせが好ましい。このような，ポリマーブレンドの例としては，下記条件を満足するＣ，Ｄ二種のポリマーからなる組み合わせが挙げられるが，もちろんこれに限定されるものではない。
Ｃは，モノマーユニットａ，ｂからなる重合度５０以上の共重合体である。
Ｄは，ホモポリマーであっても共重合体であっても良いが，Ｄを構成するモノマーユニットａのみからなる重合度５０以上でのホモポリマーとのブレンドにおいては完全相溶系であり，かつＣを構成するモノマーユニットｂのみからなる重合度５０以上のホモポリマーとのブレンドにおいては非相溶系である。
【００２３】
ここでいう，完全相溶系，および非相溶系とは前述の通りである。前記組み合わせ（Ｃ／Ｄ）の中でも，繊維素材として，コストおよび力学特性のバランスから，ランダム共重合体（Ｃ）を構成する一方の成分がエチレンテレフタレ−トであるものが好ましい。また，繊維形成性の点からは，少なくとも１成分以上結晶性ポリマ−を含むことが好ましい。本発明でいう結晶性ポリマーとは，示差走査熱量計（ＤＳＣ）にて，融点の観察されるポリマーであれば特に限定するものではない。具体的には，例えばポリエチレンテレフタレート，ポリエチレンナフタレート，ポリブチレンテレフタレートやそれらの共重合体等の芳香族ポリエステル系，およびポリ−ε−カプロラクトン等の脂肪族ポリエステル系，あるいはナイロン６，ナイロン６６等の脂肪族ポリアミド系，あるいはポリエチレン，ポリプロピレン，ポリビニルアルコール，ポリ塩化ビニル等のポリオレフィン・ビニル系，ポリオキシメチレン等のポリーエーテル系等が挙げられる。
【００２４】
実際に，上限臨界共溶温度型の相図を有し，かつ繊維形成性に優れる結晶性ポリマ−を含むポリマ−ブレンドの組み合わせとしては，ポリエチレンテレフタレ−ト−ポリエチレンナフタレ−ト共重合体／ポリエ−テルイミド系やポリエチレンテレフタレート−ポリブチレンテレフタレート共重合体／塩素化ポリエチレン，ポリスチレン／ポリ−ε−カプロラクトン系等が挙げられる。特に，ポリエチレンテレフタレ−ト−ポリエチレンナフタレ−ト共重合体／ポリエ−テルイミド系では，ポリエチレンテレフタレ−ト−ポリエチレンナフタレ−ト共重合体の共重合比がブレンド系の相溶性と強く関連しており，エチレンテレフタレート単位が９９モルを越える場合は，非相溶系となり，紡糸不安定性や力学特性の不良等，従来からの非相溶ブレンド紡糸の欠点を改善することができない。また，エチレンテレフタレート単位が５０モルを下回る場合は，完全相溶系となるため，繊維に相分離形態を付与することができない。従って，エチレンテレフタレ−トとエチレンナフタレ−トの共重合割合が，エチレンテレフタレ−ト単位が９９〜５０モルに対してエチレンナフタレ−ト単位が１〜５０モルであることが望ましい。さらに，力学特性や相分離構造付与の容易さから，エチレンテレフタレ−トとエチレンナフタレ−トの共重合割合が，エチレンテレフタレ−ト単位が９５〜７０モルに対してエチレンナフタレ−ト単位が５〜３０モルであることが，より好ましい。
【００２５】
また，用いるポリマ−中には，必要に応じて，カ−ボンブラック，酸化チタン，酸化アルミニウム，酸化ケイ素，酸化カルシウム，マイカ，金属微細粉，有機顔料，無機顔料，抗酸化剤，蛍光増白剤，難燃剤，帯電防止剤，溌水剤，吸湿剤，吸水剤，粘度調整剤，紫外線吸収剤など，通常用いられる添加剤を配合しても良い。
【００２６】
本発明の提供する新規なポリマーブレンド繊維の製造法は，特定の温度域で互いに相溶する部分相溶系のポリマ−ブレンドを相溶状態でノズルより押し出すことにより，従来から試みられている非相溶ポリマ−ブレンドの溶融紡糸時における紡糸不安定性および繊維特性の変動等の欠点を改善し，かつポリマ−ブレンドの相図を利用した相分離工程により多様な相分離構造を付与することが技術的要点である。用いるポリマーブレンドの組み合わせは，部分相溶系であれば特に限定するものであはないが，▲１▼紡糸時の冷却過程における温度ジャンプのみで相分離構造を発現し得る，また▲２▼繊維形状を保持したまま，加熱処理により相分離構造を発現し得る上限臨界共溶温度型の相図を有するポリマ−の組み合わせが好ましい。このように，相図を有するポリマ−の組み合わせの場合，相分離条件を変更することにより，分散相のサイズ・形態において多種多様の繊維を提供することができる。例えば，スピノーダル温度以上，バイノーダル温度以下で短時間処理した場合，分散相が繊維軸方向および／または断面方向に連通した形態が得られ，スピノーダル温度以上，バイノーダル温度以下で長時間処理したものは，海島状態の分散相が形成され，さらには，ガラス転移温度以上，スピノーダル温度以下で熱処理した場合は，スピノーダル温度以上，バイノーダル温度以下で得られる形態とは異なる海島状態の分散相が形成される。さらに，前記により相分離構造を形成した繊維は，一方の成分を溶剤で抽出することにより，微多孔あるいは海綿状の繊維とすることもできる。
【００２７】
相分離構造を発現させる工程は，ノズルを通過した後であれば特に限定するものではない。具体的には，ノズル通過後の巻取り時における冷却過程，巻取り後の延伸・熱処理過程，織物の精錬又染色工程，未延伸糸，延伸糸への熱処理あるいは水分付与による相分離等が挙げられる。
【００２８】
【実施例】
以下，具体的に実施例を説明するが，本発明はこれらに制限されるものではない。
【００２９】
実施例１
（ａ）成分としてエチレンテレフタレ−トとエチレンナフタレ−トとの共重合体をエチレンテレフタレ−ト：エチレンナフタレ−ト＝９：１となるよう常法により合成した共重合ポリエステル（固有粘度０．６：フエノ−ル／テトラクロロエタン＝６／４（ｖ／ｖ），３０℃）を用い，（ｂ）成分として下記一般式化３で示されるポリエ−テルイミド樹脂，ウルテム−１０００（ゼネラルエレクトリック社製）を用いた。（ａ）成分は結晶性，（ｂ）成分は非晶性ポリマ−である。
【化３】

前記，（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べ，上限臨界共溶温度型の相図を有することを確認した。紡糸用のペレットは，ポリエ−テルイミドの組成比が３０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダ−温度３２０℃で混練り押し出した後，１２０℃で８時間真空乾燥したものを用いた。上記ペレットを孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度３１５℃，紡速５００ｍ／分で紡糸した。さらに，上記の紡糸条件において巻き取り速度のみを変更したところ，糸切れすることなく，３０分間以上巻き取れる最高紡速は，４０００ｍ／分であった。また，紡速５００ｍ／分で得られた未延伸糸を，ホットロ−ラ−およびホットプレ−トを備した延伸機にて，ホットロ−ラ−温度９０℃，ホットプレ−ト温度１４０℃，倍率３．０倍の条件で延伸した。得られた延伸糸を光学顕微鏡にて観察したところ，ボイド等の欠陥もなく良好に延伸されていることが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝０．００２ミクロン，Ｙ＝１．３，Ｐ＝１．３であった。これは，従来の非相溶系のブレンド繊維と比較し，非常に微細かつ均一なサイズであり，さらに，殆ど繊維軸方向に扁平していない新規な形態を持つものであった。
【００３０】
実施例２
実施例１において，延伸時のホットプレートの温度を１７０℃とする以外は，全く同様の実験を行った。得られた延伸糸を光学顕微鏡にて観察したところ，ボイド等の欠陥もなく良好に延伸されていることが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝０．３ミクロン，Ｙ＝１．４，Ｐ＝１．３であった。これは，実施例１と比較すると円換算直径Ｄが大きくなったものの，従来の非相溶系のブレンド繊維と比較し，非常に微細かつ均一なサイズであり，さらに，殆ど繊維軸方向に扁平していない新規な形態を持つものであった。
【００３１】
実施例３
実施例１と同一の紡糸用ペレットを用い，孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度３１５℃，紡速５００ｍ／分で巻取った未延伸糸をホットステ−ジ上，１８０℃で２０秒間加熱処理した。得られたサンプルの形態を電子顕微鏡にて観察し，後述の方法によりＤを求めた。分散相の形態は，従来の非相溶系のブレンド繊維に見られるものとも，また実施例１，２とも全く異なる形態のいわいる変調構造であり，かつＤ＝０．０１ミクロンであった。
【００３２】
実施例４
実施例３において，未延伸糸を１８０℃で６０秒間加熱処理する以外は，全く同様の実験を行った。得られたサンプルの形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝０．０８ミクロン，Ｙ＝１．３，Ｐ＝１．０であった。これは，従来の非相溶系のブレンド繊維と比較し，非常に微細かつ均一なサイズであり，さらに，実施例１，２と比較しても，繊維軸方向への扁平の極めて少ない新規な形態を持つものであった。
【００３３】
実施例５
実施例３において，未延伸糸を１８０℃で３００秒間加熱処理する以外は，全く同様の実験を行った。得られたサンプルの形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝０．４ミクロン，Ｙ＝１．６，Ｐ＝１．０であった。分散相のサイズＤは実施例１〜４と比較して大きいが，従来の非相溶系のブレンド繊維に対しては小さく，かつ均一なサイズであり，さらに，実施例１，２と比較しても，繊維軸方向への扁平の極めて少ない新規な形態を持つものであった。
【００３４】
実施例６
実施例３において，ホットプレート温度１２０℃で延伸したサンプルを製織後，９０℃，６０ｇ／ｌのＮａＯＨ水溶液で２時間処理した。得られたサンプルの繊維表面を走査型顕微鏡にて観察したところ海綿状の独特な形態であった。また，後述の方法により求めたＤは０．０１ミクロンであった。さらに，その手触りは従来から知られているポリエステル繊維のアルカリ減量加工により得られるものとは全く異なる独特なドライ感を有するものであった。
【００３５】
実施例７
（ａ）成分としてエチレンテレフタレートとエチレンナフタレートとの共重合体をエチレンテレフタレート：エチレンナフタレート＝９５：５となるよう常法により合成した共重合ポリエステル（固有粘度０．６：フェノール／テトラクロエタン＝６／４（ｖ／ｖ），３０℃）を用い、（ｂ）成分として下記一般式化４で示されるポリエーテルイミド樹脂、ウルテム−１０００（ゼネラルエレクトリック社製）を用いた。（ａ）成分は結晶性、（ｂ）成分は非晶性ポリマーである。
【化４】

前記、（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べ、上限臨界共溶温度型の相図を有することを確認した。紡糸用のペレットは、ポリエーテルイミドの組成比が１０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダー温度３２０℃で混練り押し出した後、１２０℃で８時間真空乾燥したものを用いた。上記ペレットを孔数６の紡糸口金を用い、吐出量３．６ｇ／分、紡糸温度３１５℃、紡速５００ｍ／分で紡糸した。さらに、上記の紡糸条件において巻き取れる最高紡速は、４０００ｍ／分であった。また、紡速５００ｍ／分で得られた未延伸糸を、ホットローラーおよびホットプレートを備した延伸機にて、ホットローラー温度９０℃、ホットプレート温度１４０℃、倍率４．２倍の条件で延伸した。得られた延伸糸を光学顕微鏡にて観察したところ、ボイド等の欠陥もなく良好に延伸されていることが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察し、後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は、海島構造であり、かつＤ＝０．００１ミクロン，Ｙ−１．３，Ｐ−１．３であった。これは、従来の非相溶糸のブレンド繊維と比較し、非常に繊細かつ均一なサイズであり、さらに、殆ど繊維軸方向に扁平していない新規な形態を持つものであった。
【００３６】
比較例１
（ａ）成分としてポリスチレン（重量平均分子量３５００）を用い，（ｂ）成分としてポリブタジエン（重量平均分子量２５００）を用いた。（ａ），（ｂ）両成分とも非晶性ポリマ−である。前記，（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べ，上限臨界共溶温度型の相図を有することを確認した。紡糸用のペレットは，ポリブタジエンの組成比が２０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダ−温度２２０℃で混練り押し出した後，７０℃で１２時間真空乾燥したものを用いた。種々の温度，吐出速度，巻き取り速度にて上記ペレットの紡糸を試みたが曳糸性に劣り，安定に繊維を得ることはできなかった。
【００３７】
比較例２
（ａ）成分としてナイロン６を用い，（ｂ）成分としてポリプロピレンを用いた。（ａ）（ｂ）両成分とも結晶性ポリマ−である。前記，（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べたところ，非相溶系であることが分かった。紡糸用のペレットは，ポリプロピレンの組成比が１０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダ−温度２８０℃で混練り押し出した後，１２０℃で８時間真空乾燥したものを用いた。上記ペレットを孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度２８０℃で紡糸したが，５００ｍ／分の低速巻き取り時においてもノズル背圧変動，流動不安定等が生じ糸切れが多発した。上記により，少量のみ得られた５００ｍ／分巻きの未延伸糸を，ホットロ−ラ−およびホットプレ−トを備した延伸機にて，ホットロ−ラ−温度４０℃，ホットプレ−ト温度１２０℃，倍率２．５倍の条件で延伸した。得られた延伸糸を光学顕微鏡にて観察したところ，ボイドが多数生じており，良好に延伸されていないことが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝１．２ミクロン，Ｙ＝２．６，Ｐ＝９．４であった。
【００３８】
比較例３
比較例２と同一の紡糸用ペレットを用い，孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度２８０℃，紡速５００ｍ／分で巻き取った未延伸糸をホットステ−ジ上，１００℃で２０秒間加熱処理した。得られたサンプルの形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝１．６ミクロン，Ｙ＝２．７，Ｐ＝５．８であった。
【００３９】
比較例４
比較例３において，未延伸糸を１００℃で３００秒間加熱処理する以外は，全く同様の実験を行った。得られたサンプルの形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝１．６ミクロン，Ｙ＝２．７，Ｐ＝５．２であった。
（比較例５）（ａ）成分としてエチレンテレフタレ−トとエチレンナフタレ−トとの共重合体をエチレンテレフタレ−ト：エチレンナフタレ−ト＝９７：３となるよう常法により合成した共重合ポリエステル（固有粘度０．６：フエノ−ル／テトラクロロエタン＝６／４（ｖ／ｖ），３０℃）を用いた。前記，（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べたところ，非相溶系であった。紡糸用のペレットは，ポリエ−テルイミドの組成比が３０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダ−温度３２０℃で混練り押し出した後，１２０℃で８時間真空乾燥したものを用いた。上記ペレットを孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度３１５℃，紡速５００ｍ／分で紡糸したが，ノズル背圧変動，流動不安定等が生じ糸切れが多発した。上記により，少量のみ得られた５００ｍ／分巻きの未延伸糸を，ホットロ−ラ−およびホットプレ−トを備した延伸機にて，ホットロ−ラ−温度９０℃，ホットプレ−ト温度１４０℃，倍率３．０倍の条件で延伸した。得られた延伸糸を光学顕微鏡にて観察したところ，多数のボイドが生じており，良好に延伸されていないことが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察し，後述の方法によりＤ，Ｙ，Ｐを求めた。分散相の形態は，海島構造であり，かつＤ＝１．５ミクロン，Ｙ＝２．８，Ｐ＝７．６であった。（比較例６）（ａ）成分としてエチレンテレフタレ−トとエチレンナフタレ−トとの共重合体をエチレンテレフタレ−ト：エチレンナフタレ−ト＝６０：４０となるよう常法により合成した共重合ポリエステル（固有粘度０．６：フエノ−ル／テトラクロロエタン＝６／４（ｖ／ｖ），３０℃）を用いた。前記，（ａ），（ｂ）成分のポリマーブレンドの相溶性を後述の方法により調べたところ，完全相溶系であった。紡糸用のペレットは，ポリエ−テルイミドの組成比が３０ｗｔ％となるよう（ａ）成分と（ｂ）成分とを３０ｍｍφ２軸押出機を使用してシリンダ−温度３２０℃で混練り押し出した後，１２０℃で８時間真空乾燥したものを用いた。上記ペレットを孔数６の紡糸口金を用い，吐出量３．６ｇ／分，紡糸温度３１５℃，紡速５００ｍ／分で紡糸した。さらに，上記の紡糸条件において巻き取り速度のみを変更したところ，糸切れすることなく，３０分間以上巻き取れる最高紡速は，４０００ｍ／分であった。また，紡速５００ｍ／分で得られた未延伸糸を，ホットロ−ラ−およびホットプレ−トを備した延伸機にて，ホットロ−ラ−温度９０℃，ホットプレ−ト温度１４０℃，倍率３．０倍の条件で延伸した。得られた延伸糸を光学顕微鏡にて観察したところ，ボイド等の欠陥もなく良好に延伸されていることが分かった。上記により得られた延伸糸の形態を電子顕微鏡にて観察したが，分子レベルで均一な構造であった。
実施例および比較例の結果を表１にまとめた。
【００４０】
【表１】

【００４１】
測定方法
実施例，比較例に示す測定方法および評価方法は以下に示す方法によった。
（形態観察）
ミクロトームにより切断した繊維横断面および縦断面の電子顕微鏡写真により観察した。電子顕微鏡写真を撮影する際は，ポリマーブレンドの組み合わせに応じ，次に示す手順に従い評価した。▲１▼易溶出成分／難溶出成分の組み合わせの場合：繊維横断面切断後，易溶出成分の抽出溶剤にて減量率２０％で抽出し，走査型電子顕微鏡（ＳＥＭ）にて観察する。▲２▼一方の成分のみ二重結合を有する場合：繊維横断面切断後，四酸化オスミウム（０ｓＯ４) にて染色後，透過型電子顕微鏡（ＴＥＭ）にて観察する。▲３▼一方の成分のみ芳香族系化合物である場合：四酸化ルテニウム（ＲｕＯ４) にて染色後，透過型電子顕微鏡（ＴＥＭ）にて観察する。▲４▼一方の成分がアミド結合を有する場合：リンタングステン酸にて染色後，透過型電子顕微鏡（ＴＥＭ）にて観察する。但し，これらの操作は，ポリマーの組み合わせに応じ任意に選択することができ，特に限定するものではない。
（分散相の平均面積Ｘ，円換算直径Ｄ，ばらつきを表す指標Ｙ）
相分離構造が海島構造である場合，上述の方法により，撮影した繊維横断面の電子顕微鏡写真により，任意に選んだ２０個の島相の平均面積をＸとした。但し，変調構造の場合は，明確な形状がないためＸは求めなかった。また，海島構造を形成しているものは，上記Ｘを円形に換算した場合の直径を円換算直径Ｄとした。但し，変調構造の場合は，図１０に示す通り，上述の方法により，撮影した繊維横断面の電子顕微鏡写真上に直線を引き，混合比の少ない成分を２０回通過した距離（図中ｄ）の平均をＤとした。
さらに，下式により求めたＹをばらつきの指標とした。
Ｙ＝Ｒ／Ｘ（Ｒ＝Ｘmax−Ｘmini）
（但し，Ｘは，上述の通り，任意に選んだ２０個の分散相の平均面積。Ｘmaxは，任意に選んだ２０個の分散相のうち，面積の最も大きいものから３つの平均値。Ｘminiは，任意に選んだ２０個の分散相のうち，面積の最も小さいものから３つの平均値。）但し，変調構造の場合，Ｘが求まらないためＹも求めなかった。
（相溶性の評価）
（ａ），（ｂ）両成分を溶媒キャスト法にて製膜し，所定の温度で５時間熱処理した。その後，光学顕微鏡下で相分離しているか否かを観察した。
（最高紡速の評価）
ポリマーの可紡性を見るため，異なる数種の巻取り速度で紡糸した。
（延伸性の評価）
得られた延伸糸を光学顕微鏡にて観察し，１００００平方ミクロン当たりのボイドの数が５個以下の場合，延伸性良好（○），５個を越える場合，延伸性不良（×）と評価した。
【００４２】
【発明の効果】
本発明によるポリマ−ブレンド繊維は，従来から試みられている非相溶ポリマ−ブレンドを用いた場合に生じる紡糸不安定性を著しく改善しながら，多様な相分離構造を任意に，再現性良く付与したものである。従って，（１）品質変動が少ない，（２）ボイド等の欠陥のない延伸糸を提供できる，（３）相図を利用した多様な相分離形態により広範囲な要求物性へ対応できる，等の効果を有する。特に，分散相のサイズが小さく，かつサイズ分布の小さい形態を付与することにより，例えば，相分離繊維でありながら力学特性に優れるものや，分散相を例えば撥水・溌油等の機能を付与するための反応基点としたものや，さらには分散相のみを抽出することにより，軽量・保温性，ドライタッチ，濃色鮮明性，あるいは吸水・吸湿性等の特徴を備えた繊維を提供することができる。
【図面の簡単な説明】
【図１】本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図の一例である。
【図２】本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図の一例である。
【図３】本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図の一例である。
【図４】本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図の一例である。
【図５】本発明でいう部分相溶系のポリマーブレンドの一相領域あるいは二相領域を表す図の一例である。
【図６】本発明でいう海島構造の繊維を横断面から観察した図の一例である。
【図７】本発明でいう海島構造の繊維を横断面から観察した図の一例である。
【図８】本発明でいう海島構造の繊維を横断面から観察した図の一例である。
【図９】本発明でいう海島構造の繊維を横断面から観察した図の一例である。
【図１０】本発明でいう変調構造のＤの求め方を示す図である。[0001]
BACKGROUND OF THE INVENTION
The present invention has a novel phase separation form and is widely used as a synthetic fiber having features such as texture, dyeability, light weight / heat retention, water absorption / moisture absorption, heat resistance, water repellency / oil repellency, etc. The present invention relates to a polymer blend fiber that can be produced and a method for producing the same.
[0002]
[Prior art]
Mixed spinning with polymer blends is a means of modifying synthetic fibers, for example for the purpose of improving dyeability, adjusting hygroscopicity, adjusting specific gravity, cross-linking effect, improving viscoelastic properties, and improving the texture. Application to a wide range has been attempted. In this case, the mainstream is the melt spinning method using an incompatible polymer blend.
However, when two or more types of polymer blends that are incompatible with each other are melt-spun, (1) it is difficult to mix the polymers, or the spinning stock solution becomes unstable and often causes demixing. 2) The spinning property is poor because the spinning speed cannot be increased, and the productivity is inferior. (3) The properties of the obtained fiber are likely to fluctuate.
[0003]
In order to improve these disadvantages, a dispersion polymer and a compatibilizing agent are kneaded in a molten state in advance, and then a fiber-forming polymer is mixed in a molten state and then melt-spun (Japanese Patent Laid-Open No. 4-209824). Also disclosed is a method (Japanese Patent Laid-Open No. 6-2267) in which a fiber-forming thermoplastic resin is used for the island component of the sea-island structure and the characteristics of the blend polymer are utilized while improving the yarn-making property.
[0004]
However, as long as an essentially incompatible polymer blend system is used, the size of the dispersed phase fluctuates and becomes nonuniform when subjected to shear deformation when passing through the nozzle or elongation deformation when winding. It cannot be improved sufficiently. Furthermore, since such compatibilizers are generally expensive, it has not been economically preferable. As described above, although incompatible polymer blend fibers are expected to be applied to a wide range, the above problems have not been sufficiently solved, and there are very few practical examples. .
[0005]
[Problems to be solved by the invention]
The present invention has been made paying attention to the problems in the prior art. That is, an object of the present invention is to control the fiber phase separation structure in various ways with high reproducibility through a stable spinning process. In addition, by providing a form with a small size of the dispersed phase and a small size distribution, for example, it is a phase-separated fiber but has excellent mechanical properties, and the dispersed phase has functions such as water and oil repellency. Extracting only the disperse phase from the effective reaction base point for lightening, a fiber with features such as light weight, heat retention, dry touch, deep color vividness, or water absorption / moisture absorption It is intended to provide.
[0006]
[Means for Solving the Problems]
Means for solving the above-mentioned problems, that is, the present invention is a polymer blend fiber composed of two components, and one component has a circular equivalent diameter of 0.001 to 0.4 microns in the fiber cross section. It is a novel polymer blend fiber characterized by being dispersed and phase-separated, and further a polymer blend fiber composed of two components. One component is dispersed and phase-separated in the longitudinal and transverse sections of the fiber. The ratio (P) of the circle-converted diameter (A) in the fiber cross section and the circle-converted diameter (B) in the fiber longitudinal section of the dispersed phase after phase separation is 2.0 or less as shown in the following formula (1). Is a novel polymer blend fiber characterized by
P = B / A ≦ 2.0 (1)
[0007]
The ratio (P) of the circle-converted diameter (A) in the fiber cross section and the circle-converted diameter (B) in the fiber longitudinal section of the phase-separated dispersed phase is 2.0 or less as shown in the following formula (1). The novel polymer blend fiber according to claim 1,
P = B / A ≦ 2.0 (1)
A polymer blend fiber composed of two components, a phase in which one component is dispersed and phase-separated in the longitudinal and transverse sections of the fiber, and the dispersed phase that is phase-separated communicates in the fiber axis direction and / or the cross-sectional direction. It is a novel polymer blend fiber having a separated structure, and is a novel polymer blend fiber having a circular equivalent diameter of 0.005 to 0.1 microns in the fiber cross section of the phase separated dispersed phase. A novel polymer blend fiber having a circular equivalent diameter in the fiber cross section of 0.01 to 0.1 microns,
[0008]
The phase separation structure is composed of a continuous phase and / or a dispersed phase, and the average area (X) of 20 dispersed phases arbitrarily selected from the cross section of the fiber is 0.15 square microns or less, and the index Y representing the variation is A novel polymer blend fiber of 2.0 or less,
Y = R / X (R = Xmax-Xmini)
(Where, X is the average area of 20 randomly selected dispersed phases. Xmax is the average of 3 of the 20 randomly selected dispersed phases having the largest area. Xmini is arbitrarily selected. (Of the 20 selected dispersed phases, the average value of the three areas with the smallest area.)
[0009]
A polymer having a sponge-like structure with countless microcavities of 0.001 to 5 microns in terms of a circle diameter and connected to each other, and (9) a polymer blend represented by the following formula (2) A novel polymer blend fiber which is a polymer blend with a degree ratio of 50 or less,
N = n1 / n2 (2)
(Where n1 is the degree of polymerization of the polymer having the higher degree of polymerization in the polymer blend component, and n2 is the degree of polymerization of the polymer having the lower degree of polymerization in the polymer blend component). A novel polymer blend fiber, at least one component of which is a crystalline polymer, and the polymer blend is a novel polymer blend fiber, which is a blend of polystyrene and poly-ε-caprolactone resin;
[0010]
The polymer blend is a novel polymer blend fiber composed of two types of polymers C and D satisfying the following conditions, where C is a copolymer composed of monomer units a and b and having a polymerization degree of 50 or more. D may be a homopolymer or a copolymer, and is a completely compatible system in a blend with a homopolymer having a polymerization degree of 50 or more consisting only of monomer units a constituting C, and constitutes C. In a blend with a homopolymer having a degree of polymerization of 50 or more consisting only of the monomer unit b to be used, it is incompatible.
[0011]
One component of the monomer unit constituting the copolymer (C) is a novel polymer blend fiber characterized in that it is ethylene terephthalate, and C is a polymer blend comprising ethylene terephthalate and ethylene naphtha A novel polymer blend fiber characterized in that it is a copolymer of a sheet and D is a polyetherimide resin;
[0012]
A novel polymer blend fiber in which the copolymerization ratio of ethylene terephthalate and ethylene naphthalate is from 1 to 50 mol of ethylene naphthalate units to 99 to 50 mol of ethylene terephthalate units. The polyetherimide resin is a novel polymer blend fiber represented by the following general formula 2:
[Chemical 2]

(Wherein R1 is a divalent aromatic organic group having 6 to 30 carbon atoms, R2 is a divalent aromatic organic group having 6 to 30 carbon atoms, an alkylene group or cycloalkylene having 2 to 20 carbon atoms) Or a polyorganosiloxane group chain-terminated with an alkylene group having 2 to 8 carbon atoms)
[0013]
A novel polymer characterized in that a partially compatible polymer blend consisting of two components is made into a compatible state and melt-spun, and a phase separation structure is expressed by physical or chemical means in the post-spinning process. A method for producing a blended fiber, wherein the polymer blend is a novel method for producing a polymer blended fiber having a phase diagram of the upper critical eutectic temperature type. A novel polymer blend fiber manufacturing method characterized by heat treatment at a temperature below the binodal temperature, and a heat treatment at a temperature above the spinodal temperature and below the binodal temperature in the step of developing the phase separation structure. A method for producing a fiber, comprising the production of a novel polymer blend fiber wherein at least one of the two components is a crystalline polymer. This is a method for producing a new polymer blend fiber in which the process after spinning is between the first take-up rolls for spinning, and the process after spinning is a method for producing a new polymer blend fiber in which the process is a drawing process. There is a new polymer blend fiber manufacturing method in which the post-spinning process is a textile refining or dyeing process. After the spinning process, a phase-separated structure is developed, and a new polymer is subjected to alkali weight loss treatment. It is a manufacturing method of a blend fiber.
[0014]
Details of the present invention will be described below. The main point of the present invention is that a partially compatible polymer blend that is compatible with each other in a specific temperature range is extruded from a nozzle in a compatible state, so that at the time of melt spinning of an incompatible polymer blend that has been conventionally attempted. Through various processes that improve the disadvantages such as spinning instability and fluctuations in fiber properties and use the properties of partially compatible polymer blends to provide an environment that changes from a compatible state to an incompatible state, And it is to give a form that has not existed before.
[0015]
The compatible state as referred to in the present invention refers to a state in which it is uniformly mixed at the molecular level, and specifically refers to a state in which a phase structure of 0.001 microns or more is not formed. Further, the incompatible state refers to a state in which a phase structure of 0.001 micron or more is formed when it is not in a compatible state. To determine whether the solution is in a compatible state, for example, as described in Polymer Alloys and Blends, Leszek A Utracki, Hanser Publishers, Munich Vienna New York, P64., An electron microscope, suggested scanning calorimeter (DSC), Various other methods can be used. In addition, the partially compatible polymer referred to in the present invention means both a compatible state and an incompatible state by changing a practically selectable temperature and / or a mixing ratio of two kinds of polymers constituting the polymer blend. A completely compatible polymer is a combination of polymer blends that can take various dispersion states, and is a compatible state regardless of the temperature and / or the mixing ratio of the two types of polymers constituting the polymer blend. The incompatible polymer is a polymer blend that is incompatible with the temperature and / or the mixing ratio of the two polymers constituting the polymer blend. Say a blend combination. Here, the temperature that can be practically selected means a temperature that is not less than the glass transition temperature of the polymer blend (the lowest glass transition temperature in the case of having a plurality of glass transition temperatures) and not more than the decomposition start temperature of the polymer blend.
That is, the compatible state of the polymer blend that is partially compatible, completely compatible, or incompatible can be expressed as shown in FIGS.
FIGS. 1-5 is a figure showing the 1 phase area | region or 2 phase area | region of the polymer blend of the partially compatible system said by this invention, and FIGS. 6-9 observed the fiber of the sea island composition said by this invention from the cross section. FIG. 10 is a diagram showing how to obtain the circle-converted diameter D of the modulation structure referred to in the present invention, φ in FIGS. 1 to 5 indicates the weight fraction of the A component, and the hatched portion is The two-phase region is shown, and the one-phase region is shown except for the hatched portion. In each figure, the lower limit of the temperature is the glass transition temperature of the polymer blend (if there are two or more glass transition temperatures, the lowest glass transition among them) Temperature), the upper limit is the temperature at which the polymer blend begins to decompose.
[0016]
In addition, the phase separation structure referred to in the present invention means a structure in which a non-uniform phase structure of 0.001 micron or more is formed. In the present invention, as shown in FIGS. The structure that forms island-like domains independent of the other component is the sea-island structure (A), and the structure in which both components are not independent from each other and is three-dimensionally connected is the modulation structure (B). Define. Further, the structure in which the island component of the sea-island structure is substantially removed by extraction or the like is defined as microporous, and the structure in which one component of the modulation structure is substantially removed by extraction or the like is defined as a spongy structure.
[0017]
As described above, the microstructure in the fiber that can be provided by the present invention is greatly different from the structure of the incompatible polymer blend fiber that has been attempted in the past. For example, in the conventional incompatible blend spinning, a component having a low mixing ratio forms a domain and forms a so-called sea-island structure. Even if the size of this domain is minute or uniform before spinning, it is enlarged or non-uniform due to shear deformation when passing through the nozzle or elongation deformation when winding, so the diameter D in terms of the circle in the fiber cross section Is larger than 0.4 micron, and the variation index Y is larger than 2.0 (here, the circle-converted diameter D and the variation index Y are obtained by the method described later. Y is 1 if the area of the dispersed phase is completely uniform). In this way, when D exceeds 0.4 microns, the mechanical properties such as strength are inferior compared to the synthetic fiber composed of a single component, or the characteristics of the second component that becomes the dispersed phase are given. A considerable amount of mixing ratio is required, which greatly increases the cost. Furthermore, since the pitch of the dispersed phase is large, there are problems such as that water absorption / moisture absorption, water repellency / oil repellency, deep color vividness, light weight and heat retention cannot be effectively imparted. In addition, when the variation index Y exceeds 2.0, there is a problem that the fiber property varies greatly, so that the strength is inferior or stained spots are generated. On the other hand, according to the present technology, it is possible to provide a minute and uniform dispersion size form in which the circle-equivalent diameter is 0.001 ≦ D ≦ 0.4 microns and the variation index is Y ≦ 2.0. . As described above, D ≦ 0.4 micron and Y ≦ 2.0 are phase-separated fibers, but have excellent mechanical properties and have a dispersed phase, for example, water repellent and oil-repellent functions that conflict with each other. By extracting only the dispersed phase, which can be an effective reaction base point for imparting, it is possible to impart features such as light weight, heat retention, dry touch, deep color vividness, and water absorption / hygroscopicity. It has performance or characteristics that could not be achieved with conventional incompatible blend fibers.
[0018]
In addition, in the conventional incompatible blended fiber, the polymer dispersion state in the fiber is almost determined by the type and mixing ratio of the polymer blend to be used, so that the characteristics that can be imparted are limited. On the other hand, according to the present invention, by using a single composite material and changing the phase separation conditions, it is possible to provide a wide variety of fibers in the size and form of the dispersed phase. For example, when the heat treatment is performed for a short time at a temperature higher than the spinodal temperature and lower than the binodal temperature, or when the heat treatment is performed at a temperature higher than the glass transition temperature and lower than the spinodal temperature. An unprecedented novel structure can be obtained (in the present invention, the spinodal temperature and binodal temperature are known as follows, that is, the spinodal temperature means the following by the “spinodal decomposition mechanism”. The boundary between the temperature at which the system separates and the temperature at which the phase is separated by the “nucleation and growth mechanism.” The binodal temperature is the boundary between the temperature at which the system is compatible and the temperature at which the system separates. Detailed explanations are given in, for example, Polymer Alloys and Blends, Leszek A Utracki, Hanser Publishers, Munich Vienna New York, P32. In particular, the modulation structure in which the disperse phase communicates in the fiber axis direction and / or the cross-sectional direction, which occurs when processing is performed for a short time at a temperature higher than the spinodal temperature and lower than the binodal temperature, is a sea-island structure formed by an incompatible polymer. Then, an effect that cannot be achieved can be expected. For example, in the above embodiment, since both components are in a continuous phase and the interface has a large thickness, the heat resistance of the blend fiber can be drastically improved by using a heat resistant polymer for one component. Furthermore, a spongy fiber can be obtained by extracting only one component. Since the spongy fiber thus obtained has innumerable microcavities communicating with each other, it is possible to impart performance such as water absorption and hygroscopicity that could not be achieved with conventional materials.
[0019]
Furthermore, in the conventional incompatible blended fiber, the dispersion phase is extremely elongated along the fiber axis due to the draft during spinning or drawing, so that the ratio of the circular equivalent diameter of the fiber transverse section and the longitudinal section is 2 I could only make something that exceeded. Depending on the form, even if deep color clarity and touch features are added, a great effect cannot be expected. On the other hand, in the present invention, since the process of developing the phase separation structure is after spinning, it is possible to give a dispersed phase form in which the ratio of the circular equivalent diameter of the fiber cross section and the longitudinal section is approximately 1. Is possible. In such a form, by extracting the dispersed phase, it is possible to obtain a fiber having a microporous surface, and it is possible to impart features such as touch unprecedented or deep color vividness.
[0020]
Further, in the conventional incompatible blended fiber, the size of the dispersed phase observed from the cross section of the fiber is larger than the average area X of 0.15 square microns, and the index Y representing the variation exceeds 2.0. However, when the quality is fluctuated or the undispersed yarn is in the dispersed state as described above, defects such as voids are generated at the time of drawing. On the other hand, in the present invention, since the size of the dispersed phase is fine and uniform, there is little variation in quality, and even if a phase separation structure is provided in the state of an undrawn yarn, it can be drawn easily. In particular, the phase separation structure is composed of a continuous phase and / or a dispersed phase, and the average area X of 20 dispersed phases arbitrarily selected from the fiber cross section is 0.15 square microns or less, and an index Y representing the variation thereof. Is 2.0 or less, it is significantly superior to that of an incompatible polymer blend fiber in terms of quality stability and stretchability. Further, a drawn yarn having a small dispersion phase size variation is more advantageous than conventional incompatible blend fibers particularly in terms of mechanical properties such as strength.
Furthermore, after fiber formation, the form and size of the phase separation structure can be arbitrarily controlled by refining the fabric or heat treatment during the dyeing process, etc., or it can be made microporous or spongy, etc., by etching with an easily alkaline weight loss component. Therefore, it can meet a wide range of required physical properties.
[0021]
The polymer blend described in the present invention preferably has a polymer polymerization degree ratio N of 50 or less and a partially compatible system.
N = n1 / n2 (where n1 is the degree of polymerization of the polymer with the higher degree of polymerization in the polymer blend component, and n2 is the degree of polymerization of the polymer with the lower degree of polymerization in the polymer blend component). )
The degree of polymerization described above is determined by isolating each component constituting the polymer blend by an extraction operation using a solvent in which at least one component is soluble in the polymer blend, and measuring the molecular weight of each component obtained. This can be calculated.
When N exceeds 50, the low polymerization component acts as a solvent for the high polymerization component, and the phase separation rate becomes extremely fast. Therefore, it is difficult to control the phase separation structure arbitrarily and with good reproducibility. It becomes. In addition, low molecular weight components are difficult to remain in the fiber and have a disadvantage of poor long-term persistence. Therefore, the ratio N is preferably 20 or less, more preferably 10 or less.
[0022]
The combination of the polymer blend is not particularly limited as long as it is a partially compatible system. (1) A phase separation structure can be expressed only by a cooling process with a gas or liquid after melt extrusion during spinning. (2) A combination of polymers having a phase diagram of an upper critical solution temperature type capable of developing a phase separation structure by heat treatment while maintaining the fiber shape is preferable. Examples of such polymer blends include, but are not limited to, combinations of two types of polymers C and D that satisfy the following conditions.
C is a copolymer composed of monomer units a and b and having a polymerization degree of 50 or more.
D may be a homopolymer or a copolymer, but in a blend with a homopolymer having only a monomer unit a constituting D and having a polymerization degree of 50 or more, it is completely compatible, and C In a blend with a homopolymer having a degree of polymerization of 50 or more, which is composed only of the monomer unit b constituting the above, it is incompatible.
[0023]
Here, the completely compatible system and the incompatible system are as described above. Among the combinations (C / D), as the fiber material, one in which one component constituting the random copolymer (C) is ethylene terephthalate is preferable from the balance of cost and mechanical properties. Further, from the viewpoint of fiber forming property, it is preferable that at least one component or more crystalline polymer is included. The crystalline polymer as used in the present invention is not particularly limited as long as it is a polymer whose melting point is observed by a differential scanning calorimeter (DSC). Specifically, for example, aromatic polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate and copolymers thereof, and aliphatic polyesters such as poly-ε-caprolactone, nylon 6, nylon 66, etc. Examples thereof include aliphatic polyamides, polyolefins / vinyls such as polyethylene, polypropylene, polyvinyl alcohol, and polyvinyl chloride, and polyethers such as polyoxymethylene.
[0024]
Actually, a combination of a polymer blend containing a crystalline polymer having an upper critical solution temperature type phase diagram and excellent in fiber forming property is a polyethylene terephthalate-polyethylene naphthalate copolymer. / Poly-terimide, polyethylene terephthalate-polybutylene terephthalate copolymer / chlorinated polyethylene, polystyrene / poly-ε-caprolactone, and the like. Especially in polyethylene terephthalate-polyethylene naphthalate copolymer / polyetherimide system, the copolymerization ratio of polyethylene terephthalate-polyethylene naphthalate copolymer is strongly related to the compatibility of blend system. However, when the ethylene terephthalate unit exceeds 99 mol, it becomes an incompatible system, and the disadvantages of conventional incompatible blend spinning such as spinning instability and poor mechanical properties cannot be improved. In addition, when the ethylene terephthalate unit is less than 50 moles, it becomes a completely compatible system, so that the phase separation form cannot be imparted to the fiber. Accordingly, the copolymerization ratio of ethylene terephthalate and ethylene naphthalate is desirably 1 to 50 mol of ethylene naphthalate unit with respect to 99 to 50 mol of ethylene terephthalate unit. Furthermore, the copolymerization ratio of ethylene terephthalate and ethylene naphthalate is from ethylene naphthalate to 95 to 70 moles of ethylene terephthalate units because of mechanical properties and ease of imparting a phase separation structure. It is more preferable that the unit is 5 to 30 mol.
[0025]
In addition, in the polymer to be used, carbon black, titanium oxide, aluminum oxide, silicon oxide, calcium oxide, mica, fine metal powder, organic pigment, inorganic pigment, antioxidant, fluorescent whitening as required. Commonly used additives such as an agent, a flame retardant, an antistatic agent, a water-repellent agent, a moisture absorbent, a water absorbent, a viscosity modifier, and an ultraviolet absorber may be blended.
[0026]
The novel polymer blend fiber manufacturing method provided by the present invention is a conventional non-compatible method in which a partially compatible polymer blend compatible with each other in a specific temperature range is extruded from a nozzle in a compatible state. It is technical to improve various disadvantages such as spinning instability and fluctuation of fiber characteristics during melt spinning of melted polymer blends, and to provide various phase separation structures by phase separation process using phase diagrams of polymer blends. The main point. The combination of polymer blends to be used is not particularly limited as long as it is a partially compatible system. (1) A phase separation structure can be expressed only by a temperature jump in the cooling process during spinning. (2) Fiber shape A combination of polymers having a phase diagram of an upper critical solution temperature type capable of expressing a phase separation structure by heat treatment while maintaining the above is preferable. Thus, in the case of a combination of polymers having phase diagrams, a wide variety of fibers can be provided in the size and form of the dispersed phase by changing the phase separation conditions. For example, when a short time treatment is performed at a temperature higher than the spinodal temperature and lower than the binodal temperature, a form in which the dispersed phase communicates with the fiber axis direction and / or the cross-sectional direction is obtained. A sea-island state disperse phase is formed. Furthermore, when heat treatment is performed at a temperature higher than the glass transition temperature and lower than the spinodal temperature, a disperse phase in a sea-island state different from the form obtained at the spinodal temperature and lower than the binodal temperature is formed. Further, the fiber having a phase separation structure as described above can be made into a microporous or spongy fiber by extracting one component with a solvent.
[0027]
The step of developing the phase separation structure is not particularly limited as long as it passes through the nozzle. Specific examples include the cooling process during winding after passing through the nozzle, the drawing / heat treatment process after winding, the smelting or dyeing process of the fabric, the undrawn yarn, the heat treatment of the drawn yarn, or phase separation by applying moisture. It is done.
[0028]
【Example】
Hereinafter, although an Example is described concretely, this invention is not restrict | limited to these.
[0029]
Example 1
As a component (a), a copolymer polyester of ethylene terephthalate and ethylene naphthalate synthesized by a conventional method so as to be ethylene terephthalate: ethylene naphthalate = 9: 1 (inherent Viscosity 0.6: phenol / tetrachloroethane = 6/4 (v / v), 30 ° C.), as a component (b), a polyetherimide resin represented by the following general formula 3, Ultem-1000 (General Electric). The component (a) is crystalline, and the component (b) is an amorphous polymer.
[Chemical 3]

The compatibility of the polymer blends of the components (a) and (b) was examined by the method described later, and it was confirmed that it had an upper critical solution temperature type phase diagram. The pellets for spinning were extruded by kneading and extruding the component (a) and the component (b) at a cylinder temperature of 320 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polyetherimide was 30 wt%. What was vacuum-dried at 8 degreeC for 8 hours was used. The pellets were spun using a spinneret with 6 holes, a discharge rate of 3.6 g / min, a spinning temperature of 315 ° C., and a spinning speed of 500 m / min. Furthermore, when only the winding speed was changed under the above spinning conditions, the maximum spinning speed at which winding was possible for 30 minutes or more without breaking the yarn was 4000 m / min. Further, an undrawn yarn obtained at a spinning speed of 500 m / min was subjected to a hot roller temperature of 90 ° C., a hot plate temperature of 140 ° C., and a magnification of 3. 3 in a drawing machine equipped with a hot roller and a hot plate. The film was stretched under the condition of 0 times. When the obtained drawn yarn was observed with an optical microscope, it was found that the drawn yarn was well drawn without defects such as voids. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 0.002 microns, Y = 1.3, and P = 1.3. This is a very fine and uniform size compared to conventional incompatible blended fibers, and has a new form that is almost flat in the fiber axis direction.
[0030]
Example 2
In Example 1, the same experiment was performed except that the temperature of the hot plate during stretching was 170 ° C. When the obtained drawn yarn was observed with an optical microscope, it was found that the drawn yarn was well drawn without defects such as voids. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and D, Y, and P were determined by the method described later. The dispersed phase had a sea-island structure, and D = 0.3 microns, Y = 1.4, and P = 1.3. Although the diameter D in terms of a circle is larger than that in Example 1, it is very fine and uniform in size compared to the conventional incompatible blended fiber, and is almost flat in the fiber axis direction. It had no new form.
[0031]
Example 3
Using the same spinning pellet as in Example 1, using a spinneret with 6 holes, the undrawn yarn wound at a discharge rate of 3.6 g / min, a spinning temperature of 315 ° C., and a spinning speed of 500 m / min is used as a hot stage. Above, heat treatment was performed at 180 ° C. for 20 seconds. The form of the obtained sample was observed with an electron microscope, and D was determined by the method described later. The form of the dispersed phase was a modulation structure having a form completely different from that seen in the conventional incompatible blend fibers and also from Examples 1 and 2, and D = 0.01 microns.
[0032]
Example 4
In Example 3, the same experiment was performed except that the undrawn yarn was heat-treated at 180 ° C. for 60 seconds. The form of the obtained sample was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 0.08 microns, Y = 1.3, P = 1.0. This is a very fine and uniform size compared to conventional incompatible blended fibers, and a new form with very little flatness in the fiber axis direction compared to Examples 1 and 2. It was something with.
[0033]
Example 5
In Example 3, the same experiment was performed except that the undrawn yarn was heated at 180 ° C. for 300 seconds. The form of the obtained sample was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 0.4 micron, Y = 1.6, and P = 1.0. The size D of the dispersed phase is larger than those of Examples 1 to 4, but is smaller and uniform than conventional incompatible blended fibers. However, it had a new shape with very little flatness in the fiber axis direction.
[0034]
Example 6
Example 3 In Example 2, a sample stretched at a hot plate temperature of 120 ° C. was weaved, and then treated with a NaOH aqueous solution of 90 g and 60 g / l for 2 hours. When the fiber surface of the obtained sample was observed with a scanning microscope, it was a spongy and unique form. Moreover, D calculated | required by the below-mentioned method was 0.01 micron. Further, the hand has a unique dry feeling which is completely different from that obtained by the alkali weight reduction processing of polyester fibers which has been conventionally known.
[0035]
Example 7
As a component (a), a copolymer of ethylene terephthalate and ethylene naphthalate synthesized by a conventional method such that ethylene terephthalate: ethylene naphthalate = 95: 5 (inherent viscosity 0.6: phenol / tetrachloroethane) = 6/4 (v / v), 30 ° C), polyetherimide resin represented by the following general formula 4 and Ultem-1000 (manufactured by General Electric Co., Ltd.) were used as the component (b). The component (a) is crystalline, and the component (b) is an amorphous polymer.
[Formula 4]

The compatibility of the polymer blends of the components (a) and (b) was examined by the method described later and confirmed to have an upper critical solution temperature type phase diagram. The pellets for spinning were kneaded and extruded at a cylinder temperature of 320 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polyetherimide was 10 wt%, and then 120 ° C. And vacuum-dried for 8 hours. The pellets were spun at a discharge rate of 3.6 g / min, a spinning temperature of 315 ° C., and a spinning speed of 500 m / min using a spinneret with 6 holes. Furthermore, the maximum spinning speed that can be taken up under the above spinning conditions was 4000 m / min. In addition, the undrawn yarn obtained at a spinning speed of 500 m / min was drawn on a drawing machine equipped with a hot roller and a hot plate under conditions of a hot roller temperature of 90 ° C., a hot plate temperature of 140 ° C., and a magnification of 4.2 times. did. When the obtained drawn yarn was observed with an optical microscope, it was found that the drawn yarn was drawn well without defects such as voids. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and D, Y, and P were determined by the method described below. The form of the dispersed phase was a sea-island structure and D = 0.001 microns, Y-1.3, P-1.3. This is a very delicate and uniform size as compared with the conventional blend fiber of incompatible yarn, and has a new form that is hardly flattened in the fiber axis direction.
[0036]
Comparative Example 1
As component (a), polystyrene (weight average molecular weight 3500) was used, and as component (b), polybutadiene (weight average molecular weight 2500) was used. Both components (a) and (b) are amorphous polymers. The compatibility of the polymer blends of the components (a) and (b) was examined by the method described later, and it was confirmed that it had an upper critical solution temperature type phase diagram. The spinning pellets were prepared by kneading and extruding the components (a) and (b) at a cylinder temperature of 220 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polybutadiene would be 20 wt%, then at 70 ° C. What was vacuum-dried for 12 hours was used. Attempts were made to spin the above pellets at various temperatures, discharge speeds, and winding speeds, but the spinning properties were inferior and fibers could not be obtained stably.
[0037]
Comparative Example 2
Nylon 6 was used as the component (a), and polypropylene was used as the component (b). (A) (b) Both components are crystalline polymers. When the compatibility of the polymer blends of the components (a) and (b) was examined by the method described later, it was found to be an incompatible system. The spinning pellets were prepared by kneading and extruding the components (a) and (b) at a cylinder temperature of 280 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polypropylene was 10 wt%, and then at 120 ° C. What was vacuum-dried for 8 hours was used. The above pellet was spun at a discharge rate of 3.6 g / min and a spinning temperature of 280 ° C. using a spinneret with 6 holes. However, nozzle back pressure fluctuation, flow instability, etc. occurred even at a low speed of 500 m / min. Many yarn breaks occurred. Using the above-described undrawn yarn of only 500 m / minute wound with a hot roller and a hot plate, a hot roller temperature of 40 ° C., a hot plate temperature of 120 ° C., and a magnification The film was stretched under 2.5 times condition. When the obtained drawn yarn was observed with an optical microscope, it was found that many voids were formed and the drawn yarn was not drawn well. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 1.2 microns, Y = 2.6, and P = 9.4.
[0038]
Comparative Example 3
Using the same spinning pellets as in Comparative Example 2, using a spinneret with 6 holes, the undrawn yarn wound at a discharge rate of 3.6 g / min, a spinning temperature of 280 ° C., and a spinning speed of 500 m / min is used as a hot stage. Above, heat treatment was performed at 100 ° C. for 20 seconds. The form of the obtained sample was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 1.6 microns, Y = 2.7, and P = 5.8.
[0039]
Comparative Example 4
In Comparative Example 3, the same experiment was performed except that the undrawn yarn was heated at 100 ° C. for 300 seconds. The form of the obtained sample was observed with an electron microscope, and D, Y, and P were determined by the method described later. The form of the dispersed phase was a sea-island structure, and D = 1.6 microns, Y = 2.7, and P = 5.2.
Comparative Example 5 As a component (a), a copolymer of ethylene terephthalate and ethylene naphthalate was synthesized by a conventional method so that ethylene terephthalate: ethylene naphthalate = 97: 3. Copolyester (inherent viscosity 0.6: phenol / tetrachloroethane = 6/4 (v / v), 30 ° C.) was used. When the compatibility of the polymer blends of the components (a) and (b) was examined by the method described later, it was incompatible. The pellets for spinning were extruded by kneading and extruding the component (a) and the component (b) at a cylinder temperature of 320 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polyetherimide was 30 wt%. What was vacuum-dried at 8 degreeC for 8 hours was used. The above pellet was spun at a discharge rate of 3.6 g / min, a spinning temperature of 315 ° C., and a spinning speed of 500 m / min using a spinneret with 6 holes. did. Using the above-described undrawn yarn of only 500 m / minute wound with a hot roller and hot plate, a hot roller temperature of 90 ° C., a hot plate temperature of 140 ° C., and a magnification It extended | stretched on 3.0 times conditions. When the obtained drawn yarn was observed with an optical microscope, it was found that many voids were formed and the drawn yarn was not drawn well. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and D, Y, and P were determined by the method described later. The dispersed phase had a sea-island structure and D = 1.5 microns, Y = 2.8, and P = 7.6. (Comparative Example 6) As a component (a), a copolymer of ethylene terephthalate and ethylene naphthalate was synthesized by a conventional method so that ethylene terephthalate: ethylene naphthalate = 60: 40. Copolyester (inherent viscosity 0.6: phenol / tetrachloroethane = 6/4 (v / v), 30 ° C.) was used. When the compatibility of the polymer blends of the components (a) and (b) was examined by the method described later, it was a completely compatible system. The pellets for spinning were extruded by kneading and extruding the component (a) and the component (b) at a cylinder temperature of 320 ° C. using a 30 mmφ twin screw extruder so that the composition ratio of polyetherimide was 30 wt%. What was vacuum-dried at 8 degreeC for 8 hours was used. The pellets were spun using a spinneret with 6 holes, a discharge rate of 3.6 g / min, a spinning temperature of 315 ° C., and a spinning speed of 500 m / min. Furthermore, when only the winding speed was changed under the above spinning conditions, the maximum spinning speed at which winding was possible for 30 minutes or more without breaking the yarn was 4000 m / min. Further, an undrawn yarn obtained at a spinning speed of 500 m / min was subjected to a hot roller temperature of 90 ° C., a hot plate temperature of 140 ° C., and a magnification of 3. 3 in a drawing machine equipped with a hot roller and a hot plate. The film was stretched under the condition of 0 times. When the obtained drawn yarn was observed with an optical microscope, it was found that the drawn yarn was well drawn without defects such as voids. The shape of the drawn yarn obtained as described above was observed with an electron microscope, and the structure was uniform at the molecular level.
The results of Examples and Comparative Examples are summarized in Table 1.
[0040]
[Table 1]

[0041]
Measuring method
The measurement methods and evaluation methods shown in the examples and comparative examples were based on the following methods.
(Morphological observation)
It was observed by electron micrographs of the fiber cross section and vertical section cut by a microtome. When taking electron micrographs, evaluation was performed according to the following procedure, depending on the combination of polymer blends. (1) In the case of a combination of easily eluting components / difficultly eluting components: After cutting the cross section of the fiber, extract with an extraction solvent for easily eluting components at a weight loss rate of 20% and observe with a scanning electron microscope (SEM). (2) When only one component has a double bond: After cutting the cross section of the fiber, dye it with osmium tetroxide (0sO4), and observe with a transmission electron microscope (TEM). (3) When only one component is an aromatic compound: After staining with ruthenium tetroxide (RuO4), observe with a transmission electron microscope (TEM). (4) When one component has an amide bond: After staining with phosphotungstic acid, observe with a transmission electron microscope (TEM). However, these operations can be arbitrarily selected according to the combination of the polymers, and are not particularly limited.
(Average area X of dispersed phase, circle equivalent diameter D, index Y representing variation)
In the case where the phase separation structure is a sea-island structure, the average area of 20 island phases arbitrarily selected from the electron micrograph of the fiber cross-section taken by the above-described method is X. However, in the case of the modulation structure, X was not obtained because there was no clear shape. Moreover, what formed the sea island structure made the diameter at the time of converting said X into a circle into the circle conversion diameter D. However, in the case of a modulation structure, as shown in FIG. 10, a distance was drawn 20 times through a component having a low mixing ratio by drawing a straight line on the photographed electron micrograph of the cross section of the fiber as described above (d in the figure). The average of D was D.
Furthermore, Y obtained by the following equation was used as an index of variation.
Y = R / X (R = Xmax-Xmini)
(However, X is the average area of 20 arbitrarily selected dispersed phases as described above. Xmax is the average of the 3 areas having the largest area among 20 arbitrarily selected dispersed phases. Xmini Is an average of three of the 20 dispersed phases selected arbitrarily, from the smallest area.) However, in the case of the modulation structure, Y is not obtained because X cannot be obtained.
(Compatibility evaluation)
(A), (b) Both components were formed into a film by the solvent cast method, and heat-processed at predetermined temperature for 5 hours. Thereafter, it was observed whether or not phase separation was performed under an optical microscope.
(Evaluation of maximum spinning speed)
In order to see the spinnability of the polymer, spinning was performed at several different winding speeds.
(Evaluation of stretchability)
The obtained drawn yarn was observed with an optical microscope. When the number of voids per 10,000 square microns was 5 or less, the drawability was good (◯), and when it exceeded 5, the drawability was poor (x). .
[0042]
【The invention's effect】
The polymer blend fiber according to the present invention arbitrarily imparts various phase-separated structures with good reproducibility while remarkably improving the spinning instability that occurs when a conventionally incompatible polymer blend is used. Is. Therefore, (1) the quality fluctuation is small, (2) it is possible to provide a drawn yarn free from defects such as voids, and (3) a variety of phase separation forms using phase diagrams can meet a wide range of required physical properties. Have In particular, by imparting a form with a small dispersed phase size and a small size distribution, for example, although it is a phase-separated fiber, it has excellent mechanical properties, and the dispersed phase has functions such as water repellency and straw oil. To provide fibers with features such as light weight, heat retention, dry touch, deep color vividness, or water absorption / moisture absorption, by extracting only the dispersed phase as the reaction starting point Can do.
[Brief description of the drawings]
FIG. 1 is an example of a diagram showing a one-phase region or a two-phase region of a partially compatible polymer blend referred to in the present invention.
FIG. 2 is an example of a diagram showing a one-phase region or a two-phase region of a partially compatible polymer blend referred to in the present invention.
FIG. 3 is an example of a diagram showing a one-phase region or a two-phase region of a partially compatible polymer blend referred to in the present invention.
FIG. 4 is an example of a diagram showing a one-phase region or a two-phase region of a partially compatible polymer blend referred to in the present invention.
FIG. 5 is an example of a diagram showing a one-phase region or a two-phase region of a partially compatible polymer blend referred to in the present invention.
FIG. 6 is an example of a view of the sea-island structure fiber referred to in the present invention observed from a cross section.
FIG. 7 is an example of a view of the sea-island structure fiber referred to in the present invention observed from a cross section.
FIG. 8 is an example of a diagram in which the sea-island structure fiber referred to in the present invention is observed from a cross section.
FIG. 9 is an example of a view of a sea-island structure fiber referred to in the present invention observed from a cross section.
FIG. 10 is a diagram showing how to obtain D of a modulation structure according to the present invention.

Claims

It is a polymer blend fiber composed of two components, and one component is dispersed and phase-separated in a circular equivalent diameter of 0.001 to 0.4 microns in the fiber cross section, and in the fiber longitudinal and cross section. One component is dispersed and phase-separated, and the ratio (P) of the circle-converted diameter (A) in the fiber transverse section and the circle-converted diameter (B) in the fiber longitudinal section of the phase-separated dispersed phase is as follows ( 1) As shown in the formula, it is 2.0 or less ,
P = B / A ≦ 2.0 (1)
A novel polymer blend fiber, wherein the polymer blend is composed of two types of polymers C and D satisfying the following conditions.
Here, C is a copolymer having a degree of polymerization of 50 or more composed of monomer units a and b.
D may be a homopolymer or a copolymer, but in a blend with a homopolymer having a degree of polymerization of 50 or more consisting only of monomer unit a constituting C, D is completely compatible and constitutes C In a blend with a homopolymer having a degree of polymerization of 50 or more consisting only of the monomer unit b to be used, it is incompatible.

A polymer blend fiber composed of two components, in which one component is dispersed and phase-separated in the longitudinal and transverse sections of the fiber, and the dispersed phase that is phase-separated has a form that communicates in the fiber axial direction and / or cross-sectional direction. The novel polymer blend fiber according to claim 1, which has a phase separation structure.

The novel polymer blend fiber according to any one of claims 1 to 2, wherein a diameter in terms of a circle in a fiber cross section of the dispersed phase after phase separation is 0.005 to 0.1 microns.

The novel polymer blend fiber according to any one of claims 1 to 3, wherein a diameter in terms of a circle in a fiber cross section of the phase-separated dispersed phase is 0.01 to 0.1 microns.

5. The novel polymer blend fiber according to claim 1, wherein the polymer blend is a polymer blend having a polymerization degree ratio N represented by the following formula (2) of 50 or less.
N = n1 / n2 (2)
(Where n1 is the degree of polymerization of the polymer having the higher degree of polymerization in the polymer blend component, and n2 is the degree of polymerization of the polymer having the lower degree of polymerization in the polymer blend component.)

6. The novel polymer blend fiber according to claim 1, wherein at least one of the two components is a crystalline polymer.

A novel polymer blend fiber according to any one of claims 1 to 6, wherein the polymer blend is a blend of polystyrene and poly-ε-caprolactone resin.

8. The novel polymer blend fiber according to claim 1 , wherein one component of the monomer unit constituting the copolymer ( C ) is ethylene terephthalate.

9. The novel polymer blend according to claim 1 , wherein C is a copolymer of ethylene terephthalate and ethylene naphthalate, and D is a polyetherimide resin. fiber.

Ethylene terephthalate - DOO ethylene naphthalate - copolymerization ratio of bets is ethylene terephthalate - Units ethylene naphthalate against 99-50 mole - of claim 9 Units is 1 to 50 mol New polymer blend fiber.

11. The novel polymer blend fiber according to claim 9 , wherein the polyetherimide resin is represented by the following general formula 1.

(Wherein R1 is a divalent aromatic organic group having 6 to 30 carbon atoms, R2 is a divalent aromatic organic group having 6 to 30 carbon atoms, an alkylene group or cycloalkylene having 2 to 20 carbon atoms) Or a polyorganosiloxane group chain-terminated with an alkylene group having 2 to 8 carbon atoms)

Sponges in which the polymer blend fiber according to any one of claims 1 to 11 is subjected to an alkali weight loss treatment, and there are innumerable microcavities of 0.001 to 5 microns in diameter in terms of a circle, and each is connected to each other. A fiber having a shape structure.

The polymer blend fiber according to any one of claims 1 to 11 is melt-spun in a compatible state using a partially compatible polymer blend composed of two components, and physical or chemical means in a post-spinning process A process for producing a novel polymer blend fiber characterized by exhibiting a phase-separated structure by the method.

The polymer blend fibers according to any one of claims 1 to 11, polymer - blend, novel polymer of claim 13 having a phase diagram of the upper critical solution temperature type - preparation of the blend fibers.

15. The novel polymer according to claim 14 , wherein the polymer blend fiber according to any one of claims 1 to 11 is heat-treated at a glass transition temperature or higher and a binodal temperature or lower in the step of developing a phase separation structure. A method for producing blended fibers.

15. The novel polymer blend according to claim 14 , wherein the polymer blend fiber according to claim 1 is heat-treated at a temperature not lower than the spinodal temperature and not higher than the binodal temperature in the step of developing a phase separation structure. Fiber manufacturing method.

The polymer blend fiber according to any one of claims 1 to 11, wherein at least one of the two components is a crystalline polymer. The method for producing a novel polymer blend fiber according to any one of claims 13 to 16. .

The method for producing a novel polymer blend fiber according to any one of claims 13 to 17 , wherein in the polymer blend fiber according to any one of claims 1 to 11, the step after spinning is between the first spinning rolls. .

The method for producing a novel polymer blend fiber according to any one of claims 13 to 17 , wherein in the polymer blend fiber according to any one of claims 1 to 11, the step after spinning is a drawing step.

The method for producing a novel polymer blend fiber according to any one of claims 13 to 17 , wherein in the polymer blend fiber according to any one of claims 1 to 11, the step after spinning is a refining or dyeing step of a fabric. .

In the polymer blend fibers according to any one of claims 1 to 11, after expression a phase separation structure in a later step spinning, according to any one of claims 13 to 20, characterized in that the processing alkali reduction New polymer blend fiber manufacturing method.