JP3719884B2 - Method for producing polyketone fiber - Google Patents

Description

（ここで、Ｒは炭素数１〜３０の有機基である。）
【０００９】
ポリケトンは、繰り返し単位の１０重量％未満で式（ａ）のケトン以外の繰り返し単位を有していてもよい。このポリケトンは、カルボニル基とＲ基が交互に配列されているポリマーである。このポリマー中には部分的にカルボニル基同士、アルキレン基同士が結合していてもよいが、９５重量％以上が完全交互共重合体、すなわち、Ｒの次にはカルボニル基が結合し、カルボニル基の次にはＲが結合する交互共重合体からなるポリケトンであることが耐熱性、耐光性を向上させる観点から好ましい。もちろん、完全交互共重合した部分の含有率は高ければ高いほどよく、好ましくは９７重量％以上であり、最も好ましくは１００重量％である。
【００１０】
Ｒは、炭素数が１〜３０の有機基であり、例えば、メチレン、エチレン、プロピレン、ブチレン、１−フェニルエチレン等が例示される。これらの水素原子の一部または全部が、ハロゲン原子、エステル基、カルボキシル基、アミド基、水酸基、エーテル結合等の原子や基で置換されていてもよい。もちろん、Ｒは２種以上であってもよく、例えば、エチレンとプロピレンが混在していてもよい。
これらのポリケトンとしては、Ｒがエチレンの完全交互共重合単位から構成されるポリケトンが、高強度、高弾性率、高温での寸法安定性が優れるという観点から最も好ましい。本発明で使用するポリケトンの［η］は２．５以上であることが好ましい。これは、２．５未満では、耐摩耗性、耐熱性等に優れた繊維が得られにくくなるからである。得られる繊維の強度と紡糸性の兼ね合いから、好ましくは３〜１５、最も好ましくは４〜１０である。
【００１１】
本発明に用いるポリケトンの製造方法については、公知の方法をそのまま、あるいは修正して用いることができる。例えば、一酸化炭素とエチレンやプロピレン等のオレフィンを、パラジウム、ニッケル、コバルト等の第VIII族遷移金属化合物、下記の構造式で示されるリン系二座配位子及び、ｐＫａが４以下の酸のアニオンからなる触媒下でメタノールなどの溶媒下、圧力を１０ＭＰａから１００ＭＰａの高圧下で重合させて、本発明で用いるポリケトンを製造することができる。
Ｒ’Ｒ”Ｐ−Ｒ−ＰＲ’”Ｒ””
（ここで、Ｒ’、Ｒ”、Ｒ’”、Ｒ””は異種又は同種の炭素数１〜３０の有機基であり、Ｒは炭素数２〜５の有機基である。）
本発明のポリケトン繊維中には、分子量が１００００以下であって、（１）〜（１２）の化合物群から選ばれた少なくとも１つの化合物を０．００１〜１０重量％含有することが必要である。これらの化合物をポリケトン繊維に含有させることで、熱延伸時の［η］低下を抑制する共に、ポリケトン繊維の耐摩耗性、耐熱性、耐光性等の産業用資材用途に要求される耐久性を大きく向上させることが可能となる。
【００１２】
以下、（１）〜（１２）の化合物の説明を行う。
化合物（１）は、次の構造式で示されるものであり、いわゆるヒンダードフェノール系酸化防止剤である。
【化６】

（ここで、Ｒ¹ 、Ｒ² は、水素原子又は炭素数１〜１０の有機基であり、Ｘは、水素原子又は炭素数１〜４００の有機基から選ばれた基を示す。）
【００１３】
化合物（１）は、化合物（１）〜（１２）の中で、本発明の目的を達成するために最も効果が高い添加剤である。化合物（１）を添加することで、特に熱延伸時での繊維の［η］の低下や熱架橋物の生成を抑制するのに大きな効果を示すと同時に、得られた繊維の耐熱性、耐光性、耐摩擦摩耗性等を向上させるのに大きく寄与する。化合物（１）において、Ｒ¹ 、Ｒ² は、水素原子、又は炭素数１〜１０の有機基であり、Ｘは、水素原子又は、炭素数１〜４００の有機基から選ばれた基を示す。Ｒ¹ 、Ｒ² としては、水素原子又は炭素数１〜１０の有機基であれば特に制限は無く、ベンゼン環への結合位置も特に制限はない。
【００１４】
また、炭素数１〜１０の有機基の場合、炭素に結合する水素原子の一部または全部がハロゲン原子、エーテル結合、エステル結合、アミド結合、イミド結合、チオエーテル結合、チオエステル結合、水酸基、カルボニル結合等の官能基で置換されていてもよく、これらの官能基で結合されていても良い。更には、Ｒ¹ 、Ｒ² 中に他のフェノール性ベンゼン環を有していても良い。好ましくはＲ¹ 、Ｒ² のいずれか一方、または両方がｔ−ブチル基であることが、化合物（１）の熱延伸時に繊維の［η］の低下を抑制する効果が大きいので特に好ましい。
また、Ｘとしては、水素原子又は炭素数１〜４００の有機基であれば特に制限はなく、また炭素数１〜４００の有機基の場合、炭素に結合する水素原子の一部または全部がハロゲン原子、エーテル結合、エステル結合、アミド結合、イミド結合、チオエーテル結合、チオエステル結合、水酸基、カルボニル結合等の官能基で置換されていてもよい。更には、Ｒ¹ 、Ｒ² 、Ｘ中に他のフェノール性ベンゼン環を１個以上有していてもよい。
【００１５】
これらの化合物（１）の具体的例としては、ペンタエリストリールテトラキス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４ヒドロキシフェニル）プロピオネート］、チオジエチレンビス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４−ヒドロキシフェニル）プロピオネート］、オクタデシル−３−（３，５−ジ−ｔｅｒｔ−ブチル−４−ヒドロキシフェニル）プロピオネート、Ｎ，Ｎ’−ヘキサン−１，６−ジイルビス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４―ヒドロキシフェニルプロピオナミド］、ベンゼンプロパン酸，３，５−ビス（１，１−ジメチルエチル）−４−ヒドロキシ，Ｃ７−Ｃ９側鎖アルキルエステル、２，４−ジメチル−６−（１−メチルペンタデシル）フェノール、ジエチル［［３，５−ビス（１，１−ジメチルエチル）−４−ヒドロキシフェニル］メチル］ホスフォネート、３，３’，３”，５，５’，５”−ヘキサ−ｔｅｒｔ−ブチル−ａ，ａ’，ａ”−（メシチレン−２，４，６−トリイル）トリ−ｐ−クレゾール、
【００１６】
カルシウムジエチルビス［［［３，５−ビス（１，１−ジメチルエチル）−４−ヒドロキシフェニル］メチル］ホスホネート］、４，６−ビス（オクチルチオメチル）−ｏ−クレゾール、エチレンビス（オキシエチレン）ビス［３−（５−ｔｅｒｔ−ブチル−４−ヒドロキシ−ｍ−トリル）プロピオネート］、ヘキサメチレンビス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４−ヒドロキシフェニル）プロピオネート］、１，３，５−トリス（３，５―ジ−ｔｅｒｔ−ブチル−４―ヒドロキシベンジル）−１，３，５−トリアジン−２，４，６（１Ｈ，３Ｈ，５Ｈ）−トリオン、２，６−ジ−ｔｅｒｔ−ブチル−４−（４，６−ビス（オクチルチオ）−１，３，５−トリアジン−２−イルアミノ）フェノール、
【００１７】
２’−３−ビス［［３−［３，５−ジ−ｔｅｒｔ−ブチル−４−ヒドロキシフェニル］プロピオニル］］プロピオノヒドラジド、ビス−（２−ヒドロキシ−ｔｅｒｔ−ブチル−５−メチルフェニル）メタン、Ｎ，Ｎ’−ビス−（２−ヒドロキシエチル）オキサルアミド、３−（４−ヒドロキシ−３，５−ｔｅｒｔ−ブチルフェニル）プロピオン酸ジエステル、トリエチレングリコールビス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４−ヒドラジンフェニル）プロパノエート］、その他には旭電化商標の“ＡＯ−３０（ＣＡＳ−Ｎｏ．１８４３−０３−４）”、“ＡＯ−４０（ＣＡＳ−Ｎｏ．８５−６０−９）”、“ＡＯ−８０（ＣＡＳ−Ｎｏ．９０４９８−９０−１）”等が挙げられ、好ましくはＮ，Ｎ’−ヘキサン−１，６−ジイルビス［３−（３，５−ジ−ｔｅｒｔ−ブチル−４―ヒドロキシフェニルプロピオナミド］、３，３’, ３”, ５, ５’, ５”−ヘキサ−ｔ−ブチル−ａ、ａ’、ａ”- （メシチレンー２, ４, ６―トレイル）トリーｐ―クレゾール、２，６−ジ−ｔｅｒｔ−ブチル−４−（４，６−ビス（オクチルチオ）−１，３，５−トリアジン−２−イルアミノ）フェノール等である。
【００１８】
化合物（１）の繊維中の含有量としては０．００１〜１０重量％である。０．００１重量％未満では効果が出ず、１０重量％を越えると延伸倍率を高めることができない。好ましくは、０．０５重量％〜２重量％、より好ましくは０．０５〜１重量％である。また、化合物の分子量としては分子量が１００００以下であることが必要である。１００００を越えると、ポリケトン繊維中への分散が悪くなり、分子量低下抑制効果や繊維の耐久性を向上させる効果が低くなってしまう。化合物の分散性と繊維からのブリードアウトが小さいという観点から好ましくは３００〜５０００であり、更に好ましくは３００〜３０００である。
【００１９】
化合物（２）は、エチルジエチルホスホノアセテートである。
化合物（２）を添加することで、熱延伸時の［η］低下や熱架橋物の生成だけでなく、長期間または高温下での使用の際に［η］の低下や熱架橋物の生成を抑制する。また、［η］低下抑制だけでなく、熱延伸時の繊維形成過程や長期間または高温下使用時の着色防止にも効果を発揮する。化合物（２）は単独で用いても構わないが、化合物（１）と併用すると［η］低下抑制効果、着色防止効果は大きくなる。
【００２０】
化合物（２）の繊維中の含有量は添加剤の効果と延伸性の兼ね合いから０．００１〜１０重量％であり、より好ましくは０．０５重量％〜１．５重量％である。
【００２１】
化合物（３）は、トリス（２，４−ジ−ブチルフェニル）フォスフォナイトで、いわゆる亜リン酸系熱安定剤である。
化合物（３）を添加することで、化合物（２）と同様に熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下や熱架橋物の生成を抑制する。また、［η］低下や熱架橋物の生成の抑制だけでなく、熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（３）は単独で用いても構わないが、通常、化合物（３）を除く化合物（１）〜（１２）の化合物と併用すると相乗効果を発揮し、［η］低下抑制や着色防止、光安定化等の耐久性向上に大きく寄与する。特に化合物（１）と併用すると、［η］低下抑制効果、着色防止効果は大きくなる。
【００２２】
【００２３】
【００２４】
また、化合物（３）の繊維中の含有量は添加剤の効果と延伸性の兼ね合いから０．００１〜１０重量％であり、より好ましくは０．０５重量％〜２重量％である。
【００２５】
化合物（４）は、ＴＩＮＵＶＩＮ １２３Ｓ（化合物Ａ：ＣＡＳ−Ｎｏ．１２９７５７−６７−１ 化合物Ｂ：ＣＡＳ−Ｎｏ．９００３−０７−０：チバ・スペシャルティ・ケミカルズ（株）社商標）で、いわゆるヒンダードアミン系光安定剤である。
【００２６】
化合物（４）を添加することで、化合物（１）〜（３）の場合のように熱延伸時の［η］低下や熱架橋物の生成を抑制する効果と共に、長期または高温下での使用の際に、光、特に屋外などの紫外線が当たる状態での［η］の低下を抑制する。化合物（４）は単独で用いても構わないが、通常、化合物（４）を除く化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制や着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）や化合物（５）と併用すると［η］低下抑制効果、光安定化効果は大きくなる。
【００２７】
【００２８】
化合物（４）の繊維中の含有量は、添加剤の効果と延伸性の兼ね合いから０．００１〜１０重量％であり、より好ましくは０．０５重量％〜２重量％である。
【００２９】
化合物（５）は、２−（２‘−ヒドロキシ−５’−メチルフェニル）ベンゾトリアゾールで、いわゆるベンゾトリアゾール系紫外線吸収剤である。
【００３０】
化合物（５）を添加することで、熱延伸時の［η］低下や熱架橋物の生成を抑制する効果と共に、長期または高温下での使用の際に光、特に屋外などの紫外線が当たる状態での［η］の低下や熱架橋物の生成を抑制する。化合物（５）は単独で用いても構わないが、通常、化合物（５）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し［η］低下抑制や着色防止、光安定化などの耐久性向上に大きく寄与する。特に化合物（１）や化合物（４）と併用すると［η］低下抑制効果、光安定化効果は大きくなる。
【００３１】
【００３２】
【００３３】
化合物（５）の繊維中の含有量は、添加剤の効果と延伸性の兼ね合いから０．００１〜１０重量％であり、より好ましくは０．０５重量％〜２重量％である。
【００３４】
化合物（６）は、ジドデシル３，３‘−チオジプロピネートで、いわゆるイオウ系耐熱安定剤である。
化合物（６）を添加することで、熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（６）は単独で用いても構わないが、通常、化合物（６）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制や着色防止、光安定化などの耐久性向上に大きく寄与する。特に化合物（１）と併用すると、［η］低下抑制効果、着色防止効果は大きくなる。
【００３５】
【００３６】
化合物（６）の繊維中の含有量は添加剤の効果と延伸性の兼ね合いから０．００１〜１０重量％であり、より好ましくは０．０５〜２重量％である。
【００３７】
化合物（７）は酸化カルシウムであり、化合物（７）を添加することで、熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（７）は単独で用いても構わないが、通常、化合物（７）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に化合物（１）又は／及び化合物（３）と併用すると［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
繊維中の含有量は、多すぎると延伸時の延伸性を阻害し、また少なすぎると熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１〜１０重量％であり、より好ましくは０．０５〜１重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍである。
【００３８】
化合物（８）は水酸化マグネシウムであり、化合物（８）を添加することで熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（８）は単独で用いても構わないが、通常、化合物（８）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）又は／及び化合物（３）と併用すると、［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
【００３９】
繊維中の含有量は、多すぎると延伸時の延伸性を阻害し、また少なすぎると熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１〜１０重量％であり、より好ましくは０．０５〜１重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍである。
【００４０】
化合物（９）は炭酸カルシウムであり、化合物（９）を添加することで熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（９）は単独で用いても構わないが、通常、化合物（９）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）のヒンダードフェノール系酸化防止剤、化合物（３）のトリス（２，４−ジ−ブチルフェニル）フォスフォナイトと併用すると［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
【００４１】
繊維中の含有量は、多すぎると延伸時の延伸性を阻害し、また少なすぎると熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１重量％〜１０重量％であり、より好ましくは０．０５重量％〜２重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１μｍ〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍ以下である。
【００４２】
化合物（１０）はチタンアルコキシドであり、化合物（１０）を添加することで、熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（１０）は単独で用いても構わないが、通常、化合物（１０）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）又は／及び化合物（３）と併用すると［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
【００４３】
繊維中の含有量は、多すぎると延伸時の延伸性を阻害し、また少なすぎると熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１〜１０重量％であり、より好ましくは０．０５〜２重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍ以下である。
【００４４】
化合物（１１）燐酸ランタンである。
化合物（１１）を添加することで、熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。化合物（１１）は単独で用いても構わないが、通常、化合物（１１）以外の化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）又は／及び化合物（３）と併用すると、［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
【００４５】
繊維中の含有量は、多すぎると延伸時の延伸性を阻害し、また少なすぎると熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１〜１０重量％であり、より好ましくは０．０５〜２重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍである。
【００４６】
化合物（１２）はカルシウムヒドロキシアパタイトであり、化合物（１２）を添加することで、熱延伸時の［η］低下だけでなく、長期または高温下での使用の際に［η］の低下を抑制する。また、［η］低下抑制だけでなく、架橋物生成抑制効果や熱延伸時の繊維形成過程や長期または高温下使用時の着色防止にも効果を発揮する。特に架橋物生成抑制効果が著しく優れている。化合物（１２）は単独で用いても構わないが、通常、化合物（１２）を除く化合物（１）〜（１２）と併用して用いると相乗効果を発揮し、［η］低下抑制、架橋物抑制、着色防止、光安定化などの耐久性向上に大きく寄与する。特に、化合物（１）又は／及び化合物（３）と併用すると、［η］低下抑制効果、架橋物抑制、着色防止効果は大きくなる。
【００４７】
繊維中の含有量は多すぎると、延伸時の延伸性を阻害し、また少なすぎると、熱架橋物の抑制などの効果が小さくなる。好ましい範囲としては０．００１〜１０重量％であり、より好ましくは０．０５〜２重量％である。粒径については延伸時の糸切れ、毛羽などの製造上の問題、更には強度、伸度などの物性上の観点から小さければ小さいほど好ましく、通常０．００００１〜１．０μｍであり、より好ましくは０．０００１〜０．５μｍである。
【００４８】
化合物（１）〜（１２）は、必要に応じて２種以上を本発明のポリケトン繊維中に含有せしめてもよい。この場合、各化合物の特性が相乗効果として発揮され、本発明の目的を高度に達成できるからである。化合物の組み合わせ、添加量の割合は、特に制限はなく、任意に選択することができるが、組み合わせの中には少なくとも化合物（１）を用いることが好ましい。２種以上組み合わせた場合も繊維中の含有量としては、０．００１〜１０重量％が好ましく、特に好ましくは、０．０１〜２重量％である。
【００４９】
以上示した添加剤を含有させることにより、本発明のポリケトン繊維は以下のような好ましい特性を付与させることができる。
すなわち、本発明のポリケトン繊維は、［η］が２. ５以上、かつ弾性率が１７６ｃＮ／ｄｔｅｘ以上が達成できる。特に優れた耐摩耗性、耐熱性を発揮するには、［η］が３以上であることが好ましく、更に好ましくは４．２以上である。［η］の上限については、特に制限はないが、湿式紡糸原液の溶解性や重合速度の観点から２０以下が好ましく、更に好ましくは、１５以下である。また、弾性率が１７６ｃＮ／ｄｔｅｘ未満であると、繊維強化複合材料、タイヤコード、ロープ等の産業用資材の状態で高い応力が掛かった場合に、容易に変形して寸法安定性が損なわれたり、ひどい場合には破壊する場合がある。好ましくは、耐久性が高いという観点から、弾性率は２６５ｃＮ／ｄｔｅｘ以上が好ましく、更に好ましくは３１０ｃＮ／ｄｔｅｘ以上である。弾性率の上限も特に制限は無いが、通常は１０６０ｃＮ／ｄｔｅｘである。
【００５０】
また、優れた耐摩耗性、耐熱性、耐光性、寸法安定性の性能を併せ持った産業用途資材としてのポリケトン繊維とは［η］と弾性率のいずれもが高い繊維である。［η］が３以上かつ弾性率が２６５ｃＮ／ｄｔｅｘ以上が好ましく、更に好ましくは、［η］が４．２以上かつ、弾性率が３１０ｃＮ／ｄｔｅｘ以上である。
更に本発明のポリケトン繊維は、結晶化度が３０％以上、結晶配向度が７０％以上であると、繊維の高温時の耐摩耗性、弾性率の低下が抑制されるので、高温で使用する用途にはより好ましい繊維と言える。結晶化度としては５０％以上が更に好ましく、結晶配向度としては７０％以上、更には９０％以上が好ましい。
【００５１】
更に本発明のポリケトン繊維は、架橋物が５重量％以下であることが必要である。ここで言う架橋物とは、ポリマーの一部が熱架橋して生成するものであり、その大部分は熱延伸時に生成する。架橋物が５重量％を越えると、繊維が脆くなり、引き裂き強度、伸度が小さくなる。架橋物が少なければ少ないほど好ましく、特に好ましくは２重量％以下であり、更に好ましくは１重量％以下である。
本発明のポリケトン繊維の製造方法は、得られる繊維の力学物性が優れているという観点から溶液紡糸である。
【００５２】
また、溶液紡糸を採用する場合、例えば、特開平２−１１２４１３号公報、特開平４−２２８６１３号公報、特願平１０−２３６５９５号公報などに開示されている方法に従って、溶媒としてヘキサフルオロイソプロパノール、ｍ−クレゾール、レゾルシン、亜鉛塩水溶液等を用い、例えば、０．２５から３０重量％、好ましくは０．５から２０重量％のポリマー濃度で繊維化し、ついでトルエン、エタノール、イソプロパノール、ｎ−ヘキサン、イソオクタン、アセトン、メチルエチルケトン、水などの非溶剤浴で溶剤を除去、洗浄して紡糸原糸を得ることができる。
【００５３】
中でも特願平１０−２３６５９５号公報の開示の方法、つまり溶剤として亜鉛塩水溶液、非溶剤浴として水を用いることが溶剤の低毒性、不燃性、経済性、溶剤回収性、紡糸安定性の面から最も好ましい。使用する紡口については特に制限は無いが、紡口径は０．０１〜２ｍｍ、穴数は１ホールから３０００ホールのものを使用することができる。また吐出溶液量についても特に制限は無いが、１つの紡口当たりの吐出溶液量は１〜５００ｇ／ｍｉｎの範囲が実用上好ましい。得られた紡糸原糸は痕跡の不純物を除去するために、希薄硫酸水、希薄アルカリ水などでなどで数分間から１昼夜洗浄することが好ましい。さらに、純水、イオン交換水、温水などで酸やアルカリ成分を徹底的に除去したあと、延伸工程に供する。
【００５４】
延伸速度は特に制限はないが、１〜３０００ｍ／ｍｉｎ、好ましくは生産性及び延伸性の面から１０〜２０００ｍ／ｍｉｎである。延伸方法についても特に制限は無いが、例えば、加熱ロールを用いても良いし、非加熱ロール間にホットプレートにより繊維に熱を与えても構わない。あるいは加熱ロールとホットプレートを組み合わせても良い。ロールの数、ホットプレートの数についても特に制限はないが、ロールの数は２から１０、好ましくは作業性の面から３〜５個である。ホットプレートの数も１から９、好ましくは２から４個である。加熱ロール及びホットプレートの温度は（Ｔ−１００）℃から（Ｔ＋３０）℃、好ましくは（Ｔ−５０）℃から（Ｔ＋２０）℃で延伸して最終的に所望の繊維を得ることができる（但し、Ｔは上記ポリマーの結晶融点である。）。
【００５５】
繊維に上記記載の添加剤を添加する場所としては、繊維中に均一に分散できること、かつ添加剤が添加量に対し、少なくとも１０重量％以上繊維中に確実に残る場所あるいは方法であることが必要であって、繊維が溶媒を含んだ状態であると添加剤をより均一に分散できる点から、洗浄工程から乾燥工程までの間で添加するのがよい。また、添加剤を付与する位置としては１カ所でも構わないし、２カ所以上でも構わない。例えば、洗浄乾燥工程間と巻取工程の直前に添加しても良い。
【００５６】
また、添加剤を繊維に添加する方法としては、例えば、添加剤を均一に分散させた水エマルジョンまたはアセトン、メタノールなどの有機溶媒の溶液状態で仕上げ剤ノズルを用いて直接、乾燥前後のいずれか、または両方で繊維に付着させても良いし、添加剤を含んだ浴槽に繊維を通しても構わない。また繊維に平滑性を与える仕上げ剤と同時に付着させてもよい。また２種類以上の添加剤を添加する場合には別々に異なる方法で添加しても構わない。
【００５７】
【００５８】
【００５９】
本発明のポリケトン繊維の繊度は特に制限はないが、通常単糸繊度は０．０１〜１０ｄｔｅｘ、総繊度は５〜５０００ｄｔｅｘである。
本発明のポリケトン繊維は、耐久性に優れ、かつ高強度高弾性率を発現するので、タイヤ、ベルト等の繊維強化ゴム、建材に用いる繊維強化樹脂、建材、自動車、船舶、スポーツ用品等に用いる繊維強化樹脂等の繊維強化複合材料の補強繊維として用いることができる。用いるポリケトン繊維の量は、該複合材料に用いた繊維重量の１重量％以上が性能発揮するために必要であり、好ましくは２０重量％以上、更に好ましくは５０重量％以上である。繊維強化複合材料として、特に本発明のポリケトン繊維の性能を発揮できるという観点から特に、タイヤ、ベルト、建材が好ましい。これらの製造方法としては、公知の方法を用いることができる。
【００６０】
本発明のポリケトン繊維をタイヤコードとする場合は、公知の方法を用いることができる。タイヤコードとして用いる場合は、単糸繊度は１〜４ｄｔｅｘが好ましく、総繊度は５００〜３０００ｔｅｘが好ましい。必要に応じて他の繊維、例えば、レーヨン、ポリエステル繊維、アラミド繊維、ナイロン繊維、スチール繊維等と混合使用してもよいが、好ましくはタイヤ中に含まれる全タイヤコードの２０重量％、好ましくは５０重量％以上使用されていることが性能発揮の面から好ましい。得られたポリケトン繊維は、合撚して１００〜１０００Ｔ／ｍ、好ましくは、２００〜５００Ｔ／ｍの撚りを掛けた後、すだれ織りとした後、１０〜３０％のＲＦＬ（フェノール／ホルマリンラテックス）液を付着させ、少なくとも１００℃で固着させる。ＲＦＬ樹脂の付着量は、繊維重量に対して２〜７重量％が好ましい。こうして得られたタイヤコードは、特にラジアルタイヤ用カーカス材として有用である。得られたタイヤコードをタイヤへ加工する方法としては、公知の方法を用いることができる。
【００６１】
【実施例】
本発明を以下の実施例等により更に詳しく説明するが、これらは本発明の範囲を限定するものではない。
実施例の説明中に用いられる各測定値の測定方法は、次の通りである。
（１）極限粘度［η］
極限粘度［η］は、次の定義式に基づいて求めた。
［η］＝ｌｉｍ（Ｔ−ｔ）／（ｔ・Ｃ）
Ｃ→０
定義式中のｔ及びＴは、純度９８％以上のヘキサイソプロパノール溶媒及び該ヘキサフルオロイソプロパノール溶媒に溶解したポリケトンの希釈溶液の２５℃での粘度管の流過時間である。また、Ｃは上記１００ｍｌ中のグラム単位による溶質重量値である。
【００６２】
（２）添加剤量
ＮＭＲにより測定した。
（３）結晶化度
融点測定で２００〜３００℃の範囲で得られる最大の吸熱ピーク面積から計算される熱量△Ｈ（Ｊ／ｇ）より下記式から算出した。
結晶化度＝（△Ｈ／２２５）×１００（％）
（４）結晶配向度
株式会社リガク製イメージングプレートＸ線回折装置ＲＩＮＴ２０００を用いて下記の条件で繊維の回折像を取り込んだ。
Ｘ線源 ：ＣｕＫα線
出力 ：４０ＫＶ １５２ｍＡ
カメラ長：９４. ５ｍｍ
測定時間：３分
得られた画像の２θ＝２１°付近に観察される（１１０）面を円周方向にスキャンして得られる強度分布の半値幅Ｈから下記式により算出した。
結晶配向度（％）＝〔（１８０―Ｈ）／１８０〕×１００（％）
【００６３】
（５）架橋物量
ヘキサフルオロイソプロパノールで繊維を５０℃でもはや溶解しなくなるまで溶解させ、未溶解分をＸ（ｇ）を求める。この未溶解分には、触媒や添加剤等の金属成分が存在する可能性があるので、繊維を空気中で７００℃で加熱して得られる残さをＹ（ｇ）として別途求めておいた。Ｘ−Ｙが有機物であって、しかもポリケトンの溶剤であるヘキサフルオロイソプロパノールに溶解しないものと考えられるので、これを架橋物と定義する。架橋物量は以下の式に従って算出した。

【００６４】
（６）繊維の強力（強度、伸度、弾性率）
繊維の強伸度は、ＪＩＳ−Ｌ−１０１３に準じて測定した。
（７）粘度保持率
粘度保持率は下記で定義する。

（８）融点
パーキンエルマー社製ＤＳＣを用い、窒素雰囲気下、２０℃／ｍｉｎの昇温速度で測定した。
【００６５】
（９）摩耗性の評価
繊維の摩耗性の評価は以下のように行った。
サンプルは同一繊度のものを用い、かつ以下に示す同一の評価装置にて評価した。評価装置は幅間隔が２０ｃｍの２本の平行の棒を床面に平行に配置し、摩耗観察用の繊維の一方を棒に固定し、一方には２０ｇの加重をかけ２本の平行な棒に直角に弛まないように配置した。ついで、加重をかけた繊維と同じ繊維を用いて、観察用繊維の上に直角にかつ床面に平行となるように配置し、一方を往復運動する装置に固定し、もう一方を２０ｇの加重をかけ観察用繊維に力がかかるようにした。そして毎分３０回、振幅１０ｃｍの往復運動をさせた。この時、往復運動させる繊維は観察用繊維の同じ箇所を擦るように糸道を作っておいた。往復運動を３００回（１０分間）行い、観察用の繊維の摩耗状態を光学顕微鏡にて観察した。
【００６６】
（１０）耐熱強度
繊維を枷状にサンプリングし、大気雰囲気のオーブン１７０℃で１０日間放置した後の引き裂き強度を耐熱強度として評価した。
（１１）ＵＶ強度
ＵＶ強度は繊維を枷状にサンプリングし、９９年８月の１ヶ月間屋外（延岡市）に放置後に引き裂き強度をＵＶ強度として評価した。
【００６７】
【実施例１〜１１】
エチレン／一酸化炭素共重合ポリマー（［η］＝５．３）を８重量％、塩化亜鉛６０重量％、塩化ナトリウム１０重量％、純水２２重量％の組成のドープを調整し、８０℃に保ちながら、直径０．１ｍｍのノズル５０穴から、ドープ吐出量２．５ｇ／ｍｉｎ、エアギャップ長１０ｍｍで押し出し、ポリマーに対し非溶媒である水に凝固させることにより繊維化した。ついで２％硫酸水浴にて繊維を通し、塩化亜鉛を完全に除去し、水洗ロールにて硫酸を除去して巻き取った。巻き取り速度は１３ｍ／ｍｉｎで行った。次いで、乾燥前に表１記載の添加剤１〜１１をそれそれ含む０．０５重量％のメタノール溶液に仕上げ剤ノズルを用いて付着させ、非加熱ロールの間にあるホットプレート上で速度１ｍ／ｍｉｎ、２４０℃で乾燥させた。その後、延伸温度２４０℃で６倍延伸後、更に２６５℃で２倍延伸し４．０ｄｔｅｘの繊維を得た。得られた繊維の物性等を表３に示す。添加剤１〜１１は比較例１の添加剤無しに比べて、強伸度、粘度保持率、耐熱強度、ＵＶ強度、架橋物量、摩耗性すべてにおいて良好であった。特に、化合物（１）のヒンダードフェノール系の酸化防止剤は粘度保持率が高く、強度も高く、良好であった。
【００６８】
【実施例１２〜１７】
添加剤の繊維への添加方法として、添加剤１２〜１７を水で分散させた懸濁液を仕上げ剤ノズルで未乾燥糸に付着させた以外は実施例１〜１１と同様に行った。得られた繊維の物性等を表３に示す。添加剤１２〜１７は比較例１の添加剤無しと比べて強伸度、粘度保持率、耐熱強度、ＵＶ強度、架橋物量、耐摩耗性すべてにおいて良好であった。特に、カルシウムヒドロキシアパタイトは架橋物量が少なく良好であった。
【００６９】
【実施例１８】
添加剤の種類をヒンダードフェノール系酸化防止剤の化合物（１）と亜リン酸系熱安定剤の化合物（３）の２種類にし、それぞれの濃度を０. ０５重量％のメタノール溶液にして仕上げ剤ノズルにて未乾燥糸に添加した以外は実施例１〜１１と同様に行った。得られた繊維の物性等を表３に示す。得られた繊維は添加剤単独添加に比べて、粘度保持率が高く、また強伸度、耐熱強度、ＵＶ強度も高かった。
【００７０】
【実施例１９】
添加剤の種類がヒンダードフェノール系酸化防止剤の化合物（１）とイオウ系酸化防止剤の化合物（６）の２種類にし、それぞれの濃度を０. ０５重量％のメタノール溶液にして仕上げ剤ノズルで未乾燥糸にて添加して実施例１〜１１と同様に乾燥、延伸を行い、繊度４０ｄｔｅｘの繊維を得た。更に、その繊維を延伸温度２７２℃で１. ４倍延伸し、引き続き２７７℃で１. １３倍延伸して、繊度５．６ｄｔｅｘの繊維を得た。得られた繊維の物性等を表３に示す。得られた繊維の強伸度、弾性率、耐熱強度、ＵＶ強度、粘度保持率、架橋物量、摩耗性は比較例１の添加剤無しと比べて、非常に優れたものであった。
【００７１】
【実施例２０】
添加剤の種類をヒンダードフェノール系酸化防止剤の化合物（１）、亜リン酸系熱安定剤の化合物（３）、ヒンダードアミン系光安定剤の化合物（４）の３種類にした以外は実施例１９と同様に行った。得られた繊維の物性等を表３に示す。得られた繊維の強伸度、弾性率、耐熱強度、ＵＶ強度、粘度保持率、架橋物量、摩耗性は比較例１の添加剤無しと比べて、非常に優れたものであった。
【００７２】
【実施例２１】
添加剤の添加方法として、実施例１のように仕上げ剤ノズルにてメタノール溶液で添加するのでは無く、未乾燥糸をチーズのまま実施例１と同じ添加剤０. ０５重量％のアセトン溶液に１時間含浸させた以外は、乾燥、延伸を実施例１と同様に行った。得られた繊維の物性等を表３に示す。得られた繊維の物性、耐久性は実施例１と同様であった。これは繊維に添加剤が確実に分散、含有することができれば、繊維への添加方法によらず、得られる繊維の物性あるいは耐久性はすぐれたものになることを示す。
【００７３】
【比較例１】
プロピレンを５％共重合したエチレン／プロピレン／一酸化炭素共重合ポリマー（［η］＝１．８）にヒンダードフェノール系酸化防止剤の添加剤３を０. ３重量％混ぜ、押出温度とブロック温度を２４５℃として、吐出量を２０ｇ／ｍｉｎ、紡口穴径０．２５ｍｍ、穴数５０個で紡糸した。また紡糸吐出後、紡口から１００ｍｍの位置から０．４ｍ／ｍｉｎの温度１５℃の冷風で冷却して固化した。また紡糸速度１５００ｍ／ｍｉｎにてチーズ形態で巻き取った。ついで非加熱ロール間にホットプレートを有する延伸機にてホットプレート温度２１０℃で８倍延伸した。延伸速度は８００ｍ／ｍｉｎで行った。得られた繊維の繊度は１６．７ｄｔｅｘであった。得られた繊維の物性等を表３に示す。得られた繊維は強伸度、弾性率、耐熱強度、ＵＶ強度、摩耗性すべてにおいて、添加剤無しの比較例５に比べて優れていた。
【００７４】
【比較例２】
添加剤をメタノール溶液などで付着させない以外は実施例１〜１８と同様に行った。得られた繊維の物性等を表３に示す。得られた繊維は実施例１〜２１の添加剤有りのものに比べると、強伸度、耐熱強度、ＵＶ強度、粘度保持率、架橋物量、摩耗性のすべてにおいて劣るものであった。
【００７５】
【比較例３】
エチレン／一酸化炭素共重合ポリマー（［η］＝５．３）を６重量％、ヘキサフルオロイソプロパンール９４重量％、ヒンダードフェノール系酸化防止剤である添加剤２を０. ０５重量％の組成のドープを調整し、２０℃に保ちながら、直径０．１ｍｍのノズル５０穴からドープ吐出量２．５ｇ／ｍｉｎで押し出し、ポリマーに対し非溶媒であるアセトンに凝固させることにより繊維化した。巻き取り速度は１３ｍ／ｍｉｎで行った。次いで、非加熱ロールの間にあるホットプレート上で速度１ｍ／ｍｉｎ、２４０℃で乾燥させた。その後、延伸温度２４０℃で６倍延伸後、更に２６５℃で２倍延伸し４０ｄｔｅｘの繊維を得た。得られた繊維の物性等を表３に示す。得られた繊維の強伸度、粘度保持率、耐熱強度、ＵＶ強度、架橋物量、摩耗性は添加剤を入れていない比較例２と同様であった。またＮＭＲで定量した添加剤量は０. ０００５重量％と非常にわずかであった。
【００７６】
【比較例４】
実施例１において添加剤１の量を２. ５重量％のメタノール溶液にした以外は実施例１と同様に行った。得られた繊維の物性等を表３に示す。得られた繊維は実施例１と比較して強伸度、耐熱強度、ＵＶ強度、架橋物量、摩耗性すべてにおいて劣っていた。添加剤の量が多すぎたためである。
【００７７】
【比較例５】
添加剤を入れない以外は比較例１と同様に行った。得られた繊維は比較例１と比較して粘度保持率が劣っていた。得られた繊維の物性等を表３に示す。得られた繊維は強伸度、耐熱強度、ＵＶ強度、架橋物量、摩耗性すべてにおいて劣っていた。
【００７８】
【表１】

【００７９】
【表２】

【００８０】
【表３】

【００８１】
【実施例２２】
吐出量を１０４ｇ／ｍｉｎ、紡口数を７５０ホールとした以外は実施例１と同様の方法で得た１６６７ｄｔｅｘ／７５０ｆの繊維を下撚、上撚共に、３９０Ｔ／ｍで合撚し、生コードを得た。これに２０％の樹脂量のＲＦＬを付着させ、樹脂付着率が５重量％になるように１３０℃、２２５℃の乾燥機を通した。こうして得たタイヤコードを用いて、ラジアルタイヤを作成した。
作成したラジアルタイヤをアスファルト面に１ｔの乗用車が２００ｋｍ／ｈｒで走行する場合と同じ接圧をかけながら、３５℃のアスファルト面に接触させて２００ｋｍ／ｈｒの走行する場合と同じ回転をさせ、そのまま９６時間の回転試験を行った。
９６時間後、タイヤからタイヤコードを取り出し、強度保持率を測定した。実施例２２のポリケトン繊維を用いた場合は、ＲＦＬ処理後のタイヤコードと比較して強度低下は殆ど起こっていなかった。比較として、吐出量１０４ｇ／ｍｉｎ、紡口数７５０ホールとした以外は比較例２と同様の方法で得た添加剤を含まないポリケトン繊維を用いて同様実験を行ったが、実験後のタイヤコードの強度は約６％低下していた。
【００８２】
【実施例２３】
実施例２２と同様の方法で得た１６６７ｄｔｅｘ／７５０ｆの繊維を５０ｍｍの短繊維に切断した。この短繊維を２部、パルプ３部、ポルトランセメント５７部、シリカ３８部を混合した後、湿式抄造しオートクレーブ中１２０℃で成型してスレート板を作成した。こうして得られたスレート板は強度に優れ、断面を観察したところポリケトン繊維は均一に分散していた。スレート板から取り出したポリケトン繊維の溶液粘度を測定したところ、粘度の低下はみられなかった。
しかしながら、比較として、吐出量１０４ｇ／ｍｉｎ、紡口数７５０ホールとした以外は比較例２と同様の方法で得た安定剤を含まないポリケトン繊維を用いて同様実験を行ったが、実験後のポリケトン繊維の粘度は約１２％低下していた。オートクレーブ成型の段階で、粘度低下が起こったものと思われる。
【００８３】
【実施例２４】
実施例２２のポリケトン繊維を下撚、上撚共に、３９０Ｔ／ｍで合撚し、生コードを得た。これにエポキシ樹脂を付着させ、樹脂付着率が５重量％になるように２３０℃の乾燥機を通した。こうして得た処理コードを定法に従って、上帆布、クロロプレンゴムからなる圧縮ゴム層及び下帆布の構成からなる長さ１０１６ｍｍのＢ型コグ付きＶベルトを作成した。このＶを２つのブーリー間に通し、２００ｒｐｍで２４時間回転させた。実験後、ポリケトン繊維をＶベルトから取り出し強度を測定したところ、エポキシ処理後の強度に対して殆ど強度低下は起こっていなかった。
しかしながら、比較として、吐出量１０４ｇ／ｍｉｎ、紡口数７５０ホールとした以外は比較例２と同様の方法で得た安定剤を含まないポリケトン繊維を用いて同様実験を行ったが、実験後のポリケトン繊維の強度は約１５％低下していた。
【００８４】
【発明の効果】
本発明のポリケトン繊維は、従来のポリケトン繊維と比較すると、分子量が高く、しかも熱延伸時や使用環境下での分子量の低下やポリマー劣化・変性が起こりにくいので、耐摩耗性、耐熱性、耐光性等の、産業用資材用途に要求される耐久性が優れるポリケトン繊維である。従って、本発明のポリケトン繊維は、長期にわたり繊維の性能が安定しているため、タイヤ、ベルト等の繊維強化ゴム、建材に用いる繊維強化樹脂、建材、自動車、船舶、スポーツ用品等に用いる繊維強化樹脂等の繊維強化複合材料の補強繊維として用いることができる。[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a polyketone fiber having a high molecular weight, in which a specific additive is contained to suppress a decrease in molecular weight during thermal stretching and generation of a thermal cross-linked product. More specifically, the molecular weight is high, and the durability required for industrial material applications such as wear resistance, heat resistance, and light resistance is low. The present invention relates to a polyketone fiber having excellent properties.
[0002]
[Prior art]
  In recent years, carbon monoxide and olefins such as ethylene and propylene are polymerized using a transition metal complex such as palladium or nickel as a catalyst to obtain a polyketone in which carbon monoxide and the olefin are substantially completely alternately copolymerized. (Industrial Materials, December issue, page 5, 1997). Such a polyketone is already known to become a high-strength, high-modulus fiber having a strength of 8.82 cN / dtex or more and a modulus of 176.4 cN / dtex or more by wet spinning (Japanese Patent Laid-Open No. 2-112413). Gazette, JP-A-4-228613, JP-A-4-505344, etc.). Polyketone fibers have excellent properties such as high strength, high elastic modulus, dimensional stability at high temperatures, adhesiveness, and creep resistance properties. Reinforcing fibers such as tire cords and belts using these properties. Application to composite material fibers such as concrete reinforcing fibers is expected (JP-A-2-112413, JP-A-9-324377, JP-A-9-328342, etc.).
  The present inventors have also focused on the characteristics of the above polyketone fiber and are researching its fiberization. In the process, it has been found that known polyketone fibers have serious problems when used for industrial applications.
[0003]
  The first problem is that the molecular weight of the polyketone is greatly reduced during the fiberization stage, particularly when hot drawing. The decrease in molecular weight varies depending on the drawing conditions such as drawing temperature and drawing time, but as long as a known fiberization technique is used, the intrinsic viscosity of polyketone fiber in the heat drawing process, that is, [η] is the same as that of the raw material polyketone used. It has been found that the value decreases to a fraction of [η]. In particular, such a decrease in [η] was significant when the stretching temperature and the stretching ratio were high. Furthermore, it has been found that when the hot stretching temperature is increased, the polymer is thermally crosslinked and an insoluble and infusible crosslinked product is formed in the fiber. Such polyketone fibers are generally brittle, and even when rubbed with a small stress, fluff is likely to occur, and therefore cannot be used for industrial materials.
  The second problem is that the known polyketone fiber gradually decreases in molecular weight or forms an insoluble and infusible crosslinked product when used in a state exposed to high temperature for a long time. Even if such a fiber shows high strength and high elastic modulus at the time of fiber formation, the above phenomenon occurs in the actual use stage, and as a result, the physical properties of the fiber are likely to deteriorate as the actual use time is extended. There was a problem. Such fibers cannot be used for industrial purposes.
[0004]
  For example, in Example 1q of JP-A-4-228613, an ethylene / carbon monoxide alternating copolymer (hereinafter abbreviated as “ECO”) having an intrinsic viscosity (agreement with [η]) of 5.1 is used. After dissolving in a mixed solvent of phenol and acetone, wet spinning is performed to obtain a fiber having a strength of 2.1 GPa (corresponding to about 16.8 cN / dtex) and an elastic modulus of 55.0 GPa (corresponding to about 439 cN / dtex). Yes. However, although the fiber thus obtained has high strength and elastic modulus, [η] was measured and showed a value of less than 2.5. Further, this fiber contained a large amount of a thermal cross-linked product. As described above, [η] is greatly reduced, or fibers containing a large amount of a thermal cross-linked product have poor wear resistance, and [η] is further reduced under long-term high temperature use. Furthermore, when this fiber was used outdoors for a long time, the strength and elongation decreased with time, and the fiber had poor light resistance. For these reasons, it is difficult to use in industrial applications due to practical characteristics.
[0005]
  Further, in Example 6 of JP-A-2-112413, Mw (weight average molecular weight) is 1.3 × 10 6.^Five Of polyketone is dissolved in hexafluoroisopropanol, and a solution containing a hindered phenolic antioxidant (IRGANOX1076: Ciba Geigy) in the solution is used to wet-spin the fiber in a coagulation bath and fiberize. ing. However, since this antioxidant dissolves in acetone, it falls off in the coagulation stage and does not remain in the fiber, and does not show the effect of the additive. As a result, the fiber was poor in wear resistance and heat resistance.
  As described above, within the scope of the publicly known technology, there is no knowledge of problems such as that polyketone fibers are liable to cause a decrease in [η] during hot drawing and thermal cross-linked products are easily generated, and there is no suggestion regarding their solutions. In addition, there is no description of polyketone fibers suitable for industrial materials that solve the above-mentioned problems by containing additives and have durability such as wear resistance and heat resistance.
[0006]
[Problems to be solved by the invention]
  As a result of examination from the viewpoint of durability such as abrasion resistance and heat resistance of the polyketone fiber, in the known polyketone fiber, [η] is greatly reduced in the fiberization process, particularly in the heat drawing process, and a large amount of thermal cross-linked products are used. In addition, even when used for long periods of time and at high temperatures, there are problems such as a decrease in [η] and the formation of cross-linked products. Over time, the strength, elongation, and elastic modulus decrease. As a result, it was found that practical performance such as wear resistance and heat resistance was inferior. That is, the known polyketone fiber not only is difficult to achieve high strength and high elastic modulus due to a decrease in [η] at the fiberization stage, but [η] is likely to vary from the viewpoint of industrially stable production. Also, stable performance cannot be maintained during long-term use due to external factors such as heat.
  The problem to be solved by the present invention is that the durability required for industrial material applications such as wear resistance, heat resistance, light resistance, etc. during long-term use is excellent, and at the same time, the molecular weight is high, high strength, high elasticity It is providing the polyketone fiber which expresses a rate. Specifically, [η] decrease at the fiberization stage during hot drawing and suppression of thermal cross-linked product formation, [η] decrease suppression during long-term high temperature use, cross-linked product generation control, addition to solve these problems Is the development of drugs.
[0007]
[Means for Solving the Problems]
  As a result of intensive studies to solve the above-mentioned problems, the present inventors have not included a significant decrease in [η] even at a high stretching temperature and a stretching ratio by incorporating a specific additive in the fiber production process. As a result of finding the possibility that the formation of a cross-linked product can be remarkably suppressed and further studying it, the problems of the present invention could be solved.
  That is, the present inventionIt consists of polyketone solution preparation process, fiberizing process, coagulation / washing process, drying process and stretching process90% by weight or more of the repeating unit is a method for producing a polyketone fiber represented by the following structural formula (a),Between the washing process and the drying process,At least one compound having a molecular weight of 10,000 or less and selected from the group of compounds (1) to (12)Against polyketone fiber weightContains 0.001 to 10% by weightTo add to polyketone fiberPolyketone fiber characterized byManufacturing methodIs to provide.
[0008]
  The polyketone used for producing the polyketone fiber of the present invention, and further the polyketone constituting the polyketone fiber of the present invention is a polyketone having 90% by weight or more of the repeating units represented by the following structural formula (a).
[Chemical formula 5]

(Here, R is an organic group having 1 to 30 carbon atoms.)
[0009]
  The polyketone may have a repeating unit other than the ketone of formula (a) at less than 10% by weight of the repeating unit. This polyketone is a polymer in which carbonyl groups and R groups are alternately arranged. In this polymer, carbonyl groups and alkylene groups may be partially bonded, but 95% by weight or more is a completely alternating copolymer, that is, a carbonyl group is bonded next to R, and a carbonyl group Next to the above, a polyketone composed of an alternating copolymer to which R is bonded is preferable from the viewpoint of improving heat resistance and light resistance. Of course, the higher the content of the completely alternating copolymerized portion, the better, preferably 97% by weight or more, and most preferably 100% by weight.
[0010]
  R is an organic group having 1 to 30 carbon atoms, and examples thereof include methylene, ethylene, propylene, butylene, and 1-phenylethylene. Some or all of these hydrogen atoms may be substituted with atoms or groups such as halogen atoms, ester groups, carboxyl groups, amide groups, hydroxyl groups, and ether bonds. Of course, R may be two or more, for example, ethylene and propylene may be mixed.
  As these polyketones, a polyketone composed of completely alternating copolymer units of R being ethylene is most preferable from the viewpoint of high strength, high elastic modulus, and excellent dimensional stability at high temperatures. [Η] of the polyketone used in the present invention is preferably 2.5 or more. This is because if it is less than 2.5, it is difficult to obtain fibers excellent in wear resistance, heat resistance, and the like. From the balance of strength and spinnability of the resulting fiber, it is preferably 3 to 15, and most preferably 4 to 10.
[0011]
  About the manufacturing method of the polyketone used for this invention, a well-known method can be used as it is or amended. For example, carbon monoxide and an olefin such as ethylene or propylene, a Group VIII transition metal compound such as palladium, nickel or cobalt, a phosphorus bidentate ligand represented by the following structural formula, and an acid having a pKa of 4 or less The polyketone used in the present invention can be produced by polymerizing under a catalyst comprising an anion under a solvent such as methanol under a high pressure of 10 MPa to 100 MPa.
                R'R "PR-PR '" R ""
(Here, R ′, R ″, R ′ ″, R ″ ″ are different or similar organic groups having 1 to 30 carbon atoms, and R is an organic group having 2 to 5 carbon atoms.)
  The polyketone fiber of the present invention must have a molecular weight of 10,000 or less and contain 0.001 to 10% by weight of at least one compound selected from the compound group of (1) to (12). . By containing these compounds in the polyketone fiber, the [η] drop during hot stretching is suppressed, and the durability required for industrial material applications such as wear resistance, heat resistance, and light resistance of the polyketone fiber is achieved. It is possible to greatly improve.
[0012]
  Hereinafter, the compounds (1) to (12) will be described.
  Compound (1) is represented by the following structural formula, and is a so-called hindered phenol-based antioxidant.
[Chemical 6]

(Where R¹ , R² Is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and X represents a group selected from a hydrogen atom or an organic group having 1 to 400 carbon atoms. )
[0013]
  Compound (1) is the most effective additive for achieving the object of the present invention among the compounds (1) to (12). By adding the compound (1), the fiber has a great effect in suppressing the decrease in fiber [η] and the formation of a thermal cross-linked product, particularly at the time of hot drawing, and at the same time the heat resistance and light resistance of the obtained fiber. This greatly contributes to improving the properties, friction wear resistance, and the like. In compound (1), R¹ , R² Is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and X represents a group selected from a hydrogen atom or an organic group having 1 to 400 carbon atoms. R¹ , R² There is no particular limitation as long as it is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and the bonding position to the benzene ring is not particularly limited.
[0014]
  In the case of an organic group having 1 to 10 carbon atoms, some or all of the hydrogen atoms bonded to carbon are halogen atoms, ether bonds, ester bonds, amide bonds, imide bonds, thioether bonds, thioester bonds, hydroxyl groups, and carbonyl bonds. It may be substituted with a functional group such as, or may be bonded with these functional groups. Furthermore, R¹ , R² You may have other phenolic benzene rings in it. Preferably R¹ , R² It is particularly preferable that one or both of them be a t-butyl group because the effect of suppressing the decrease in [η] of the fiber during the thermal stretching of the compound (1) is great.
  X is not particularly limited as long as it is a hydrogen atom or an organic group having 1 to 400 carbon atoms. In the case of an organic group having 1 to 400 carbon atoms, part or all of the hydrogen atoms bonded to carbon are halogen atoms. It may be substituted with a functional group such as an atom, ether bond, ester bond, amide bond, imide bond, thioether bond, thioester bond, hydroxyl group or carbonyl bond. Furthermore, R¹ , R² , X may have one or more other phenolic benzene rings.
[0015]
  Specific examples of these compounds (1) include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4hydroxyphenyl) propionate], thiodiethylenebis [3- (3,5- Di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, N, N′-hexane-1,6-diylbis [3 -(3,5-di-tert-butyl-4-hydroxyphenylpropionamide], benzenepropanoic acid, 3,5-bis (1,1-dimethylethyl) -4-hydroxy, C7-C9 side chain alkyl ester, 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl ) -4-Hydroxyphenyl] methyl] phosphonate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert-butyl-a, a ′, a ″-(mesitylene-2,4,6- Triyl) tri-p-cresol,
[0016]
Calcium diethylbis [[[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate], 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene ) Bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1, 3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di Tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol,
[0017]
2′-3-bis [[3- [3,5-di-tert-butyl-4-hydroxyphenyl] propionyl]] propionohydrazide, bis- (2-hydroxy-tert-butyl-5-methylphenyl) methane N, N′-bis- (2-hydroxyethyl) oxalamide, 3- (4-hydroxy-3,5-tert-butylphenyl) propionic acid diester, triethylene glycol bis [3- (3,5-di- tert-butyl-4-hydrazinephenyl) propanoate] and others include "AO-30 (CAS-No. 1843-03-4)" and "AO-40 (CAS-No. 85-60-9) of Asahi Denka trademark. ) "," AO-80 (CAS-No. 90498-90-1) "and the like, preferably N, N'-hexane-1,6-diylbis [ -(3,5-di-tert-butyl-4-hydroxyphenylpropionamide], 3,3 ', 3 ", 5, 5', 5" -hexa-t-butyl-a, a ', a "- (Mesitylene-2,4,6-trail) tree p-cresol, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol Etc.
[0018]
  The content of the compound (1) in the fiber is 0.001 to 10% by weight. If it is less than 0.001% by weight, no effect is obtained, and if it exceeds 10% by weight, the draw ratio cannot be increased. Preferably, it is 0.05 weight%-2 weight%, More preferably, it is 0.05-1 weight%. The molecular weight of the compound needs to be 10,000 or less. When it exceeds 10,000, the dispersion into the polyketone fiber becomes poor, and the effect of suppressing the decrease in molecular weight and the effect of improving the durability of the fiber are lowered. From the viewpoint that the dispersibility of the compound and the bleed out from the fiber are small, it is preferably 300 to 5,000, and more preferably 300 to 3,000.
[0019]
  Compound (2) isEthyl diethylphosphonoacetateIt is.
  Addition of compound (2) not only reduces [η] during hot stretching and generation of thermal cross-linked products, but also decreases [η] and generates thermal cross-linked products during long-term or high-temperature use. Suppress. In addition to suppressing the decrease in [η], the fiber formation process during hot drawing and the prevention of coloring during long-term or high-temperature use are also exhibited. The compound (2) may be used alone, but when used in combination with the compound (1), the [η] decrease suppressing effect and the coloring preventing effect are increased.
[0020]
The content of the compound (2) in the fiber is 0.001 to 10% by weight, more preferably 0.05% to 1.5% by weight in view of the effect of the additive and stretchability.
[0021]
  Compound (3) isTris (2,4-di-butylphenyl) phosphoniteIt is a so-called phosphorous acid heat stabilizer.
  Addition of compound (3) not only reduces [η] at the time of hot stretching as in compound (2), but also reduces [η] and produces a thermal cross-linked product during long-term or high-temperature use. Suppress. Moreover, it not only suppresses the decrease in [η] and the formation of thermal cross-linked products, but also exerts an effect in preventing fiber formation during hot drawing and coloration during long-term or high-temperature use. Although the compound (3) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) except the compound (3), [η] lowering suppression and coloring prevention, It greatly contributes to durability improvement such as light stabilization. In particular, when used in combination with the compound (1), the [η] decrease suppressing effect and the coloring preventing effect are enhanced.
[0022]
[0023]
[0024]
Moreover, content in the fiber of a compound (3) is 0.001 to 10 weight% from the balance of the effect of an additive, and a drawability, More preferably, it is 0.05 weight% to 2 weight%.
[0025]
  Compound (4) isTINUVIN 123S (Compound A: CAS-No. 129757-67-1 Compound B: CAS-No. 9003-07-0: Trademark of Ciba Specialty Chemicals Co., Ltd.)So-called hindered amine light stabilizers.
[0026]
  By adding the compound (4), as in the case of the compounds (1) to (3), the effect of suppressing the decrease in [η] at the time of hot stretching and the formation of a thermal cross-linked product, as well as long-term or high-temperature use In this case, the decrease in [η] in the state of being exposed to light, particularly ultraviolet rays such as outdoors, is suppressed. Although the compound (4) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) excluding the compound (4), and [η] lowering suppression and coloring prevention , Greatly contributes to durability improvement such as light stabilization. In particular, when used in combination with the compound (1) or the compound (5), the [η] decrease suppressing effect and the light stabilizing effect are increased.
[0027]
[0028]
The content of the compound (4) in the fiber is 0.001 to 10% by weight, more preferably 0.05% to 2% by weight in view of the effect of the additive and stretchability.
[0029]
  Compound (5) is2- (2′-Hydroxy-5′-methylphenyl) benzotriazoleAnd so-called benzotriazole ultraviolet absorbers.
[0030]
  Addition of compound (5) has the effect of suppressing [η] reduction during thermal stretching and the formation of thermal cross-linked products, as well as being exposed to light, particularly ultraviolet rays, such as outdoors, when used for long periods or at high temperatures. Of [η] and the formation of thermal cross-linked products are suppressed. The compound (5) may be used alone, but usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (5), and [η] lowering suppression and coloring prevention, It greatly contributes to durability improvement such as light stabilization. In particular, when used in combination with the compound (1) or the compound (4), the [η] decrease suppressing effect and the light stabilizing effect are increased.
[0031]
[0032]
[0033]
The content of the compound (5) in the fiber is 0.001 to 10% by weight, more preferably 0.05% to 2% by weight in view of the effect of the additive and stretchability.
[0034]
  Compound (6) isDidodecyl 3,3′-thiodipropinateIt is a so-called sulfur heat stabilizer.
  By adding the compound (6), not only the [η] decrease during hot stretching, but also the [η] decrease during long-term or high-temperature use is suppressed. In addition to suppressing the decrease in [η], the fiber formation process during hot drawing and the prevention of coloring during long-term or high-temperature use are also exhibited. Although the compound (6) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (6), and [η] lowering suppression or coloring prevention. , Greatly contributes to durability improvement such as light stabilization. In particular, when used in combination with the compound (1), the [η] decrease suppressing effect and the coloring preventing effect are enhanced.
[0035]
[0036]
The content of the compound (6) in the fiber is 0.001 to 10% by weight, more preferably 0.05 to 2% by weight in view of the effect of the additive and stretchability.
[0037]
  Compound (7)Calcium oxideIn addition, the addition of the compound (7) suppresses not only the decrease in [η] during hot stretching, but also the decrease in [η] during long-term or high-temperature use. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. Although the compound (7) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (7), and [η] lowering suppression, crosslinked product It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, when used in combination with the compound (1) or / and the compound (3), the [η] decrease suppressing effect, the crosslinked product suppressing effect, and the coloring preventing effect are enhanced.
  If the content in the fiber is too large, the stretchability at the time of stretching is inhibited, and if it is too small, the effect of suppressing the thermal cross-linked product becomes small. A preferable range is 0.001 to 10% by weight, and more preferably 0.05 to 1% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm.
[0038]
  Compound (8) isMagnesium hydroxideIn addition, the addition of the compound (8) suppresses not only the decrease in [η] during hot stretching, but also the decrease in [η] during long-term or high-temperature use. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. The compound (8) may be used alone, but usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (8), and [η] lowering suppression, crosslinked product. It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, when used in combination with the compound (1) or / and the compound (3), the [η] decrease suppressing effect, the crosslinked product suppressing effect, and the coloring preventing effect are enhanced.
[0039]
  If the content in the fiber is too large, the stretchability at the time of stretching is inhibited, and if it is too small, the effect of suppressing the thermal cross-linked product becomes small. A preferable range is 0.001 to 10% by weight, and more preferably 0.05 to 1% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm.
[0040]
  Compound (9) isCalcium carbonateIn addition, the addition of the compound (9) suppresses not only the decrease in [η] at the time of hot stretching, but also the decrease in [η] during long-term or high-temperature use. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. The compound (9) may be used alone, but usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (9), and [η] lowering suppression, crosslinked product It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, the hindered phenolic antioxidant of compound (1), of compound (3)Tris (2,4-di-butylphenyl) phosphoniteWhen used together, the [η] decrease suppressing effect, the cross-linked product suppressing effect, and the coloring preventing effect are enhanced.
[0041]
  If the content in the fiber is too large, the stretchability at the time of stretching is inhibited, and if it is too small, the effect of suppressing the thermal cross-linked product becomes small. A preferable range is 0.001% by weight to 10% by weight, and more preferably 0.05% by weight to 2% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 μm to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm or less.
[0042]
  Compound (10) isTitanium alkoxideIn addition, the addition of the compound (10) suppresses not only the [η] decrease during hot stretching, but also the [η] decrease during long-term or high-temperature use. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. Although the compound (10) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (10), and [η] lowering suppression, crosslinked product It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, when used in combination with the compound (1) or / and the compound (3), the [η] decrease suppressing effect, the cross-linked product suppressing effect, and the coloring preventing effect are enhanced.
[0043]
If the content in the fiber is too large, the stretchability at the time of stretching is inhibited, and if it is too small, the effect of suppressing the thermal cross-linked product becomes small. A preferable range is 0.001 to 10% by weight, and more preferably 0.05 to 2% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm or less.
[0044]
Compound (11) phosphoric acidlanthanumIt is.
By adding the compound (11), not only the [η] decrease during hot stretching, but also the [η] decrease during long-term or high-temperature use is suppressed. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. Although the compound (11) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) other than the compound (11), and [η] lowering suppression, crosslinked product It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, when used in combination with the compound (1) or / and the compound (3), the [η] decrease suppressing effect, the crosslinked product suppressing effect, and the coloring preventing effect are enhanced.
[0045]
If the content in the fiber is too large, the stretchability at the time of stretching is inhibited, and if it is too small, the effect of suppressing the thermal cross-linked product becomes small. A preferable range is 0.001 to 10% by weight, and more preferably 0.05 to 2% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm.
[0046]
  Compound (12) isCalcium hydroxyapatiteIn addition, the addition of the compound (12) suppresses not only the decrease in [η] during hot stretching, but also the decrease in [η] during long-term or high-temperature use. In addition to suppressing the decrease in [η], it also has an effect of suppressing the formation of a cross-linked product, the fiber formation process during hot drawing, and the prevention of coloring during long-term or high-temperature use. In particular, the effect of inhibiting the formation of a crosslinked product is remarkably excellent. Although the compound (12) may be used alone, it usually exhibits a synergistic effect when used in combination with the compounds (1) to (12) excluding the compound (12), and [η] lowering suppression, crosslinked product It greatly contributes to durability improvement such as suppression, coloring prevention, and light stabilization. In particular, when used in combination with the compound (1) or / and the compound (3), the [η] decrease suppressing effect, the crosslinked product suppressing effect, and the coloring preventing effect are enhanced.
[0047]
  When there is too much content in a fiber, the drawability at the time of extending | stretching will be inhibited, and when too small, effects, such as suppression of a thermal crosslinked material, will become small. A preferable range is 0.001 to 10% by weight, and more preferably 0.05 to 2% by weight. The particle size is preferably as small as possible from the viewpoint of manufacturing properties such as yarn breakage and fluff at the time of stretching, and further from the viewpoint of physical properties such as strength and elongation, and is usually 0.00001 to 1.0 μm, more preferably. Is 0.0001 to 0.5 μm.
[0048]
  Two or more compounds (1) to (12) may be contained in the polyketone fiber of the present invention as necessary. In this case, the characteristics of each compound are exhibited as a synergistic effect, and the object of the present invention can be achieved to a high degree. The combination of the compounds and the ratio of the addition amount are not particularly limited and can be arbitrarily selected. However, it is preferable to use at least compound (1) in the combination. Also when combining 2 or more types, as content in a fiber, 0.001 to 10 weight% is preferable, Most preferably, it is 0.01 to 2 weight%.
[0049]
  By containing the additive shown above, the polyketone fiber of the present invention can be given the following preferable characteristics.
  That is, the polyketone fiber of the present invention can achieve [η] of 2.5 or more and an elastic modulus of 176 cN / dtex or more. In order to exhibit particularly excellent wear resistance and heat resistance, [η] is preferably 3 or more, and more preferably 4.2 or more. Although there is no restriction | limiting in particular about the upper limit of [(eta)], 20 or less are preferable from a viewpoint of the solubility of a wet spinning stock solution and a polymerization rate, More preferably, it is 15 or less. Also, if the elastic modulus is less than 176 cN / dtex, it can be easily deformed and the dimensional stability is impaired when high stress is applied in the state of industrial materials such as fiber reinforced composite materials, tire cords and ropes. In the worst case, it may be destroyed. Preferably, from the viewpoint of high durability, the elastic modulus is preferably 265 cN / dtex or more, and more preferably 310 cN / dtex or more. The upper limit of the elastic modulus is not particularly limited, but is usually 1060 cN / dtex.
[0050]
  Polyketone fiber as an industrial material having excellent wear resistance, heat resistance, light resistance, and dimensional stability is a fiber having a high [η] and a high elastic modulus. [Η] is 3 or more and the elastic modulus is preferably 265 cN / dtex or more, and more preferably [η] is 4.2 or more and the elastic modulus is 310 cN / dtex or more.
  Furthermore, when the polyketone fiber of the present invention has a crystallinity of 30% or more and a crystal orientation of 70% or more, the wear resistance and elastic modulus of the fiber at high temperatures are suppressed, so that it is used at high temperatures. It can be said that it is a more preferable fiber for use. The degree of crystallinity is more preferably 50% or more, and the degree of crystal orientation is preferably 70% or more, more preferably 90% or more.
[0051]
  Furthermore, in the polyketone fiber of the present invention, the cross-linked product should be 5% by weight or less.is necessary. The cross-linked product referred to here is a product formed by thermally cross-linking a part of the polymer, and most of it is generated during hot stretching. If the cross-linked product exceeds 5% by weight, the fiber becomes brittle and the tear strength and elongation become small. The smaller the cross-linked product is, the more preferable, particularly preferably 2% by weight or less, and more preferably 1% by weight or less.
  The production method of the polyketone fiber of the present invention is as follows:GetSolution spinning from the viewpoint of excellent mechanical propertiesIs.
[0052]
  Further, when employing solution spinning, for example, according to the methods disclosed in JP-A-2-112413, JP-A-4-228613, Japanese Patent Application No. 10-236595, etc., hexafluoroisopropanol as a solvent, Using m-cresol, resorcin, aqueous zinc salt solution, etc., for example, fiberized at a polymer concentration of 0.25 to 30% by weight, preferably 0.5 to 20% by weight, and then toluene, ethanol, isopropanol, n-hexane, The spinning yarn can be obtained by removing the solvent in a non-solvent bath such as isooctane, acetone, methyl ethyl ketone, water, and washing.
[0053]
  Among them, the method disclosed in Japanese Patent Application No. 10-236595, that is, the use of a zinc salt aqueous solution as a solvent and water as a non-solvent bath is a low solvent toxicity, nonflammability, economy, solvent recoverability, and spinning stability. To most preferred. There are no particular restrictions on the spinneret used, but those having a spinneret diameter of 0.01 to 2 mm and a number of holes of 1 to 3000 holes can be used. Also, the amount of the discharged solution is not particularly limited, but the amount of discharged solution per one nozzle is preferably in the range of 1 to 500 g / min. The obtained spinning yarn is preferably washed with dilute sulfuric acid water, dilute alkaline water or the like for several minutes to one day in order to remove trace impurities. Further, after thoroughly removing acid and alkali components with pure water, ion exchange water, warm water, etc., it is subjected to a stretching process.
[0054]
  The stretching speed is not particularly limited, but is 1 to 3000 m / min, preferably 10 to 2000 m / min from the viewpoint of productivity and stretchability. Although there is no restriction | limiting in particular also about the extending | stretching method, For example, you may use a heating roll and may heat a fiber with a hotplate between non-heating rolls. Alternatively, a heating roll and a hot plate may be combined. The number of rolls and the number of hot plates are not particularly limited, but the number of rolls is 2 to 10, preferably 3 to 5 from the viewpoint of workability. The number of hot plates is also 1 to 9, preferably 2 to 4. The heating roll and hot plate can be drawn at a temperature of (T-100) ° C. to (T + 30) ° C., preferably (T-50) ° C. to (T + 20) ° C. to obtain the desired fiber finally (however, , T is the crystalline melting point of the polymer.)
[0055]
  The place where the above-mentioned additive is added to the fiber should be a place or method that can be uniformly dispersed in the fiber and that the additive remains reliably in the fiber at least 10% by weight or more with respect to the added amount. InWhatWhen the fiber is in a state containing a solvent, the additive can be more uniformly dispersed, so that it is preferable to add the fiber between the washing step and the drying step. Further, the position where the additive is applied may be one, or two or more. For example, it may be added between the washing and drying process and immediately before the winding process.
[0056]
  In addition, as a method of adding the additive to the fiber, for example, either a water emulsion in which the additive is uniformly dispersed or a solution state of an organic solvent such as acetone or methanol is used either directly before or after drying using a finisher nozzle. Alternatively, both of them may be attached to the fiber, or the fiber may be passed through a bathtub containing an additive. Moreover, you may make it adhere simultaneously with the finishing agent which gives the fiber smoothness. When two or more kinds of additives are added, they may be added separately by different methods.
[0057]
[0058]
[0059]
  The fineness of the polyketone fiber of the present invention is not particularly limited, but usually the single yarn fineness is 0.01 to 10 dtex, and the total fineness is 5 to 5000 dtex.
  Since the polyketone fiber of the present invention is excellent in durability and exhibits high strength and high elastic modulus, it is used in fiber reinforced rubber such as tires and belts, fiber reinforced resin used in building materials, building materials, automobiles, ships, sports equipment, etc. It can be used as a reinforcing fiber for a fiber-reinforced composite material such as a fiber-reinforced resin. The amount of polyketone fiber to be used is necessary for performance to be 1% by weight or more of the fiber weight used in the composite material, preferably 20% by weight or more, and more preferably 50% by weight or more. As the fiber-reinforced composite material, tires, belts, and building materials are particularly preferable from the viewpoint that the performance of the polyketone fiber of the present invention can be exhibited. As these production methods, known methods can be used.
[0060]
  When the polyketone fiber of the present invention is used as a tire cord, a known method can be used. When used as a tire cord, the single yarn fineness is preferably 1 to 4 dtex, and the total fineness is preferably 500 to 3000 tex. If necessary, it may be mixed with other fibers such as rayon, polyester fiber, aramid fiber, nylon fiber, steel fiber, etc., but preferably 20% by weight of the total tire cord contained in the tire, preferably 50% by weight or more is preferably used from the viewpoint of performance. The obtained polyketone fiber is twisted and twisted at 100 to 1000 T / m, preferably 200 to 500 T / m, and then made into a weave and then 10-30% RFL (phenol / formalin latex) Allow the liquid to adhere and fix at least 100 ° C. The adhesion amount of the RFL resin is preferably 2 to 7% by weight with respect to the fiber weight. The tire cord thus obtained is particularly useful as a carcass material for radial tires. As a method of processing the obtained tire cord into a tire, a known method can be used.
[0061]
【Example】
  The present invention will be described in more detail with reference to the following examples, etc., but these do not limit the scope of the present invention.
  The measurement method of each measurement value used in the description of the examples is as follows.
(1) Intrinsic viscosity [η]
  The intrinsic viscosity [η] was determined based on the following defining formula.
      [Η] = lim (T−t) / (t · C)
              C → 0
  “T” and “T” in the definition formula are the flow time of a viscosity tube at 25 ° C. of a diluted solution of a polyketone dissolved in a hexaisopropanol solvent having a purity of 98% or more and the hexafluoroisopropanol solvent. C is the solute weight value in grams in 100 ml.
[0062]
(2) Amount of additive
  Measured by NMR.
(3) Crystallinity
  The calorific value was calculated from the following equation from the amount of heat ΔH (J / g) calculated from the maximum endothermic peak area obtained in the range of 200 to 300 ° C. by melting point measurement.
      Crystallinity = (ΔH / 225) × 100 (%)
(4) Degree of crystal orientation
  Using a Rigaku Imaging Plate X-ray diffractometer RINT2000, fiber diffraction images were captured under the following conditions.
      X-ray source: CuKα ray
      Output: 40KV 152mA
      Camera length: 94.5mm
      Measurement time: 3 minutes
  The obtained image was calculated from the half width H of the intensity distribution obtained by scanning the (110) plane observed in the vicinity of 2θ = 21 ° in the circumferential direction by the following equation.
      Degree of crystal orientation (%) = [(180−H) / 180] × 100 (%)
[0063]
(5) Amount of cross-linked product
  The fiber is dissolved with hexafluoroisopropanol until it no longer dissolves at 50 ° C., and the undissolved content is determined as X (g). Since this undissolved component may contain metal components such as a catalyst and an additive, the residue obtained by heating the fiber in air at 700 ° C. was separately obtained as Y (g). Since it is considered that XY is an organic substance and does not dissolve in hexafluoroisopropanol which is a polyketone solvent, this is defined as a crosslinked product. The amount of the cross-linked product was calculated according to the following formula.

[0064]
(6) Fiber strength (strength, elongation, elastic modulus)
  The high elongation of the fiber was measured according to JIS-L-1013.
(7) Viscosity retention
  Viscosity retention is defined below.

(8) Melting point
  Using a DSC manufactured by Perkin Elmer, measurement was performed at a temperature increase rate of 20 ° C./min in a nitrogen atmosphere.
[0065]
(9) Evaluation of wearability
  Evaluation of the abrasion property of the fiber was performed as follows.
  Samples having the same fineness were used and evaluated with the same evaluation apparatus shown below. The evaluation device is arranged with two parallel bars with a width of 20 cm parallel to the floor surface, and one of the fibers for wear observation is fixed to the bar, and one of the two parallel bars is subjected to a load of 20 g. It was arranged so that it would not sag at a right angle. Then, using the same fiber as the weighted fiber, place it on the observation fiber so that it is perpendicular to the floor and parallel to the floor, fix one to the reciprocating device, and the other to the weight of 20 g. To apply force to the observation fiber. A reciprocating motion with an amplitude of 10 cm was performed 30 times per minute. At this time, a yarn path was made so that the reciprocating fiber rubs the same portion of the observation fiber. The reciprocating motion was performed 300 times (10 minutes), and the abrasion state of the observation fiber was observed with an optical microscope.
[0066]
(10) Heat resistance strength
  The fibers were sampled in a bowl shape, and the tear strength after being left in an oven at 170 ° C. in an air atmosphere for 10 days was evaluated as the heat resistant strength.
(11) UV intensity
  The UV intensity was evaluated by measuring the tear strength as UV intensity after sampling the fiber in a bowl shape and leaving it outdoors (Nobeoka City) for one month in August 1999.
[0067]
Examples 1 to 11
  A dope having a composition of 8% by weight of an ethylene / carbon monoxide copolymer ([η] = 5.3), 60% by weight of zinc chloride, 10% by weight of sodium chloride, and 22% by weight of pure water was adjusted to 80 ° C. While maintaining, the fiber was extruded from 50 nozzle holes with a diameter of 0.1 mm at a dope discharge rate of 2.5 g / min and an air gap length of 10 mm, and solidified in water as a non-solvent for the polymer. Next, the fiber was passed through a 2% sulfuric acid water bath to completely remove zinc chloride, and the sulfuric acid was removed with a water washing roll and wound up. The winding speed was 13 m / min. Then, before drying, it was applied to a 0.05 wt% methanol solution containing the additives 1 to 11 listed in Table 1 using a finish nozzle, and the speed was 1 m / m on a hot plate between unheated rolls. It was made to dry at 240 degreeC for min. Thereafter, the fiber was stretched 6 times at a stretching temperature of 240 ° C., and further stretched 2 times at 265 ° C. to obtain 4.0 dtex fibers. Table 3 shows the physical properties and the like of the obtained fiber. Additives 1 to 11 were better in all of the strength, elongation, viscosity retention, heat resistance, UV strength, amount of cross-linked product, and wear than the additive of Comparative Example 1 without additives. In particular, the hindered phenol-based antioxidant of the compound (1) had a high viscosity retention rate and high strength, which was good.
[0068]
Examples 12-17
  The additive was added to the fiber in the same manner as in Examples 1 to 11 except that a suspension in which additives 12 to 17 were dispersed in water was attached to the undried yarn with a finish nozzle. Table 3 shows the physical properties and the like of the obtained fiber. Additives 12 to 17 were good in all of the strength, elongation, viscosity retention, heat resistance, UV strength, amount of cross-linked product, and wear resistance compared to Comparative Example 1 without the additive. In particular, calcium hydroxyapatite was good with a small amount of cross-linked product.
[0069]
Example 18
  Two types of additives, hindered phenolic antioxidant compound (1) and phosphorous acid thermal stabilizer compound (3), are added to each solution in a 0.05% by weight methanol solution. It carried out similarly to Examples 1-11 except having added to the undried thread with the agent nozzle. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber had higher viscosity retention and higher elongation, heat resistance, and UV strength than the additive alone.
[0070]
Example 19
  There are two types of additives: hindered phenolic antioxidant compound (1) and sulfur antioxidant compound (6), and each concentration is 0.05 wt% methanol solution and finish nozzle And dried and stretched in the same manner as in Examples 1 to 11 to obtain fibers having a fineness of 40 dtex. Further, the fiber was stretched 1.4 times at a stretching temperature of 272 ° C. and then stretched 1.13 times at 277 ° C. to obtain a fiber having a fineness of 5.6 dtex. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber had very high elongation, elastic modulus, heat resistance, UV strength, viscosity retention, amount of cross-linked product and abrasion as compared with the additive of Comparative Example 1 without any additives.
[0071]
Example 20
  Example except that the kind of additive was changed to three kinds of compound (1) of hindered phenolic antioxidant, compound (3) of phosphorous acid heat stabilizer and compound (4) of hindered amine light stabilizer The same as 19 was carried out. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber had very high elongation, elastic modulus, heat resistance, UV strength, viscosity retention, amount of cross-linked product, and abrasion as compared with the additive of Comparative Example 1 without any additives.
[0072]
Example 21
  As a method of adding the additive, instead of adding the methanol solution with a finisher nozzle as in Example 1, the undried yarn remains as cheese in the same additive 0.05% acetone solution as in Example 1. Drying and stretching were performed in the same manner as in Example 1 except that the impregnation was performed for 1 hour. Table 3 shows the physical properties and the like of the obtained fiber. The physical properties and durability of the obtained fiber were the same as in Example 1. This indicates that if the additive can be reliably dispersed and contained in the fiber, the properties or durability of the resulting fiber will be excellent regardless of the method of addition to the fiber.
[0073]
[Comparative Example 1]
  Mixing 3% by weight of hindered phenolic antioxidant additive 3 with ethylene / propylene / carbon monoxide copolymer polymer ([η] = 1.8) copolymerized with 5% propylene, extrusion temperature and block Spinning was performed at a temperature of 245 ° C., a discharge rate of 20 g / min, a nozzle hole diameter of 0.25 mm, and 50 holes. Moreover, after spinning discharge, it cooled and solidified with the cold air of the temperature of 15 degreeC of 0.4 m / min from the position of 100 mm from the spinning nozzle. Moreover, it wound up with the cheese form at the spinning speed of 1500 m / min. Next, the film was stretched 8 times at a hot plate temperature of 210 ° C. by a stretching machine having a hot plate between non-heated rolls. The stretching speed was 800 m / min. The fineness of the obtained fiber was 16.7 dtex. Table 3 shows the physical properties and the like of the obtained fiber. The resulting fiber is a comparative example with no additives in all of high elongation, elastic modulus, heat resistance, UV strength, and abrasion5It was better than
[0074]
[Comparative example2]
  It carried out similarly to Examples 1-18 except not making an additive adhere with methanol solution etc. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber was inferior in all of high elongation, heat resistance, UV strength, viscosity retention, amount of cross-linked product, and wear compared to those of Examples 1 to 21 with additives.
[0075]
[Comparative example3]
  6% by weight of an ethylene / carbon monoxide copolymer ([η] = 5.3), 94% by weight of hexafluoroisopropanol, and 0.05% by weight of Additive 2 as a hindered phenol antioxidant While adjusting the dope of the composition and keeping it at 20 ° C., it was extruded from a nozzle 50 hole with a diameter of 0.1 mm at a dope discharge rate of 2.5 g / min and solidified into acetone which is a non-solvent for the polymer to be fiberized. The winding speed was 13 m / min. Subsequently, it was dried at a speed of 1 m / min and 240 ° C. on a hot plate between non-heated rolls. Thereafter, the fiber was stretched 6 times at a stretching temperature of 240 ° C., and further stretched 2 times at 265 ° C. to obtain a 40 dtex fiber. Table 3 shows the physical properties and the like of the obtained fiber. Comparative examples in which the fiber obtained has high elongation, viscosity retention, heat resistance, UV strength, amount of cross-linked product, and abrasion resistance without additives.2It was the same. The amount of additive determined by NMR was very small, 0.0005% by weight.
[0076]
[Comparative example4]
  The same procedure as in Example 1 was conducted except that the amount of additive 1 in Example 1 was changed to a 2.5 wt% methanol solution. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber was inferior in all of the high elongation, heat resistance, UV strength, amount of cross-linked product, and abrasion as compared with Example 1. This is because the amount of the additive was too large.
[0077]
[Comparative example5]
  Except without additivesComparative Example 1As well as. The resulting fiber isComparative Example 1The viscosity retention was inferior compared with. Table 3 shows the physical properties and the like of the obtained fiber. The obtained fiber was inferior in all of high elongation, heat resistance, UV strength, amount of cross-linked product, and abrasion.
[0078]
[Table 1]

[0079]
[Table 2]

[0080]
[Table 3]

[0081]
【Example22]
  Except for the discharge rate of 104 g / min and the number of nozzles of 750 holes, the 1667 dtex / 750f fiber obtained in the same manner as in Example 1 was twisted at 390 T / m for both the lower twist and the upper twist, and the raw cord was Obtained. RFL having a resin amount of 20% was adhered to this, and passed through a dryer at 130 ° C. and 225 ° C. so that the resin adhesion rate was 5% by weight. A radial tire was created using the tire cord thus obtained.
  While applying the same contact pressure as the 1t passenger car traveling at 200 km / hr on the asphalt surface of the created radial tire, contact the 35 ° C. asphalt surface and rotate the same as when traveling at 200 km / hr. A 96 hour rotation test was performed.
  After 96 hours, the tire cord was taken out from the tire and the strength retention was measured. Example22When the polyketone fiber was used, there was almost no decrease in strength compared to the tire cord after RFL treatment. For comparison, a comparative example except that the discharge rate was 104 g / min and the number of nozzles was 750 holes.2The same experiment was conducted using polyketone fibers containing no additive obtained by the same method as described above, but the strength of the tire cord after the experiment was reduced by about 6%.
[0082]
【Example23]
  Example22The 1667 dtex / 750f fiber obtained in the same manner as above was cut into 50 mm short fibers. After mixing 2 parts of this short fiber, 3 parts of pulp, 57 parts of portulan cement, and 38 parts of silica, wet papermaking and molding at 120 ° C. in an autoclave to prepare a slate plate. The slate plate thus obtained was excellent in strength, and the cross section was observed. As a result, the polyketone fibers were uniformly dispersed. When the solution viscosity of the polyketone fiber taken out from the slate plate was measured, no decrease in viscosity was observed.
  However, for comparison, a comparative example except that the discharge rate was 104 g / min and the number of nozzles was 750 holes.2The same experiment was conducted using polyketone fibers containing no stabilizer obtained by the same method as in Example 1, but the viscosity of the polyketone fibers after the experiment was reduced by about 12%. It is thought that viscosity reduction occurred at the autoclave molding stage.
[0083]
Example 24
  Example22The polyketone fiber was twisted at 390 T / m for both the lower twist and the upper twist to obtain a raw cord. An epoxy resin was adhered thereto, and a 230 ° C. dryer was passed so that the resin adhesion rate was 5% by weight. A treated cord obtained in this manner was used to produce a B-shaped cogged V-belt having a length of 1016 mm comprising the upper canvas, the compressed rubber layer made of chloroprene rubber, and the lower canvas. This V was passed between two bouleys and rotated at 200 rpm for 24 hours. After the experiment, the polyketone fiber was taken out of the V-belt and the strength was measured. As a result, the strength did not substantially decrease with respect to the strength after the epoxy treatment.
  However, for comparison, a comparative example except that the discharge rate was 104 g / min and the number of nozzles was 750 holes.2The same experiment was conducted using polyketone fibers containing no stabilizer obtained by the same method as described above, but the strength of the polyketone fibers after the experiment was reduced by about 15%.
[0084]
【The invention's effect】
  The polyketone fiber of the present invention has a higher molecular weight than conventional polyketone fibers, and is less susceptible to molecular weight reduction and polymer degradation / denaturation during hot drawing or in the use environment. It is a polyketone fiber with excellent durability required for industrial materials, such as properties. Therefore, since the polyketone fiber of the present invention has stable fiber performance over a long period of time, fiber reinforced rubber such as tires and belts, fiber reinforced resin used for building materials, fiber reinforced resins used for building materials, automobiles, ships, sports equipment, etc. It can be used as a reinforcing fiber for fiber reinforced composite materials such as resins.

Claims (1)

90% by weight or more of a repeating unit consisting of a polyketone solution preparation step, a fiberizing step, a coagulation / washing step, a drying step and a drawing step is a polyketone fiber production method represented by the following structural formula (a), and the washing step During the drying process, the molecular weight is 10,000 or less, and at least one compound selected from the following group of compounds (1) to (12) is contained in an amount of 0.001 to 10% by weight based on the weight of the polyketone fiber A method for producing a polyketone fiber, comprising adding to the polyketone fiber as described above.

(Here, R is an organic group having 1 to 30 carbon atoms.)

(Here, R ¹ and R ² are a hydrogen atom or an organic group having 1 to 10 carbon atoms, and X represents a group selected from a hydrogen atom or an organic group having 1 to 400 carbon atoms.)
Ethyl diethylphosphonoacetate (2)
Tris (2,4-di-butylphenyl) phosphonite (3)
TINUVIN 123S (CAS-No. 63843-89-0: Trademark of Ciba Geigy) (4)
2- (2′-hydroxy-5′-methylphenyl) benzotriazole (5)
Didodecyl 3,3′-thiodipropinate (6)
Calcium oxide (7)
Magnesium hydroxide (8)
Calcium carbonate (9)
Titanium alkoxide (10)
Lanthanum phosphate (11)
Calcium hydroxyapatite (12)