JPS61152811A - High tenacity acrylic fiber yarn and production thereof - Google Patents
High tenacity acrylic fiber yarn and production thereofInfo
- Publication number
- JPS61152811A JPS61152811A JP27317184A JP27317184A JPS61152811A JP S61152811 A JPS61152811 A JP S61152811A JP 27317184 A JP27317184 A JP 27317184A JP 27317184 A JP27317184 A JP 27317184A JP S61152811 A JPS61152811 A JP S61152811A
- Authority
- JP
- Japan
- Prior art keywords
- strength
- yarn
- polymer
- acrylonitrile
- spinning
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
- Artificial Filaments (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は高強度アクリル系繊維糸条、すなわちマルチフ
ィラメント、特に従来の市販アクリル系繊維に比較して
繊維の機械的強度が極めて大きく、繊維表面の平滑性に
優れた高強度アクリロニトリル繊維糸条およびその工業
的製造法に関する。Detailed Description of the Invention (Field of Industrial Application) The present invention is a high-strength acrylic fiber yarn, that is, a multifilament. This invention relates to a high-strength acrylonitrile fiber yarn with excellent surface smoothness and an industrial method for producing the same.
（従来の技術）
従来アクリル系繊維（以下、ＡＮ系繊維と略す）は、衣
料用として大量に生産、販売されているが、工業用また
は産業用としては、機械的強度が十分ではないためにほ
とんど使用されていないのが現状である。(Prior art) Conventional acrylic fibers (hereinafter abbreviated as AN fibers) are produced and sold in large quantities for clothing, but they are not suitable for industrial or industrial use because they do not have sufficient mechanical strength. Currently, it is hardly used.
これまでにＡＮ系繊維の機械的強度を改良もしくは向上
させようとする多くの試みが提案されてきた。Many attempts have been proposed to date to improve or increase the mechanical strength of AN-based fibers.
たとえば、特開昭５７−５１８１０号公報には、湿式ま
たは乾式紡糸方法により得られた繊維を湿式延伸し、緊
張下に乾燥し、引き続いて接触延伸して有効全延伸倍率
を９倍以上２５倍以下にする方法が提案され、これによ
って、高弾性率のＡＮ系繊維を得ることができることが
記載されている。For example, Japanese Patent Application Laid-Open No. 57-51810 discloses that fibers obtained by a wet or dry spinning method are wet-stretched, dried under tension, and then contact-stretched to increase the effective total stretching ratio from 9 times to 25 times. The following method is proposed, and it is described that AN-based fibers with a high modulus of elasticity can be obtained by this method.
ざらに、特開昭５７−１６１１１７号公報には、相対粘
度が２．５〜６．０のＡＮ系ポリマを乾式または湿式紡
糸し、洗浄もしくは洗浄後に湿式延伸し、緊張下に加熱
ロール上で乾燥し、乾熱下延伸し、ざらに乾熱下に熱処
理する方法が提案されており、これによって高強度ＡＮ
系繊維が得られることが記載されている。In general, JP-A-57-161117 discloses that an AN-based polymer having a relative viscosity of 2.5 to 6.0 is spun by dry or wet processes, washed or wet-stretched after washing, and then stretched on heated rolls under tension. A method of drying, stretching under dry heat, and rough heat treatment under dry heat has been proposed.
It is described that a fiber based on this method can be obtained.
しかしながら、これらの公知技術によって得られるＡＮ
系繊維の強度は、たとえば引張強度が最大的１０ｇ／ｄ
未満程度であり、しかも引張強度の向上は、他の機械的
性質、たとえば引張弾性率や結節強度を低下させるケー
スが多く、引張強度のみならず弾性率や結節強度などの
他の機械的性質を総合的に向上、改良するものではなく
、引張り強度が約２０（Ｊ／ｄに及ぶデュポン社の“ケ
ブラー”に代表される仝芳香族ポリアミド繊維のように
、複合材料の補強繊維に要求される繊維物性を満足する
ものではない。However, the AN obtained by these known techniques
The strength of the fibers is, for example, a maximum tensile strength of 10 g/d.
Furthermore, improvements in tensile strength often reduce other mechanical properties, such as tensile modulus and knot strength. It is not a comprehensive improvement or improvement, but is required for reinforcing fibers in composite materials, such as aromatic polyamide fibers such as DuPont's Kevlar, which has a tensile strength of approximately 20 J/d. It does not satisfy the fiber properties.
ざらに最近に至って１、特開昭５９−１９９８０９号公
報には、分子量が４０万のＡＮ系ポリマを減圧、脱泡し
ながらその溶剤に溶解し、得られた紡糸原液を紡出、凝
固させた後、後工程になるほど高温度の条件下で多段延
伸し、次いで１３０℃以下の緊張下に乾燥する方法を採
用すると、２０ｐ ／ｄ以上のＡＮ系繊維が得られる旨
開示されている。Recently, 1, Japanese Patent Application Laid-Open No. 199809 discloses that an AN-based polymer with a molecular weight of 400,000 is dissolved in the solvent under reduced pressure and defoamed, and the resulting spinning stock solution is spun and solidified. It is disclosed that AN-based fibers of 20 p/d or more can be obtained by employing a method of multi-stage stretching under conditions of higher temperatures in subsequent steps, followed by drying under tension at 130° C. or lower.
しかしながら、この発明は、４０万という極めて高い重
量平均分子量を有するＡＮ系ポリマを使用することを前
提としているが、このような高重合度のポリマは、先ず
この公報に開示されているように、ポリビニルアルコー
ルのような分散安定剤の存在下に懸濁重合を行うなど特
殊な重合手段を採用しなければならず、ポリマの製造コ
スト面で工業的製造法としては問題があること、重合度
が大きいためにポリマ溶液の粘度が高く脱泡が難しいだ
けでなく、このポリマ溶液の粘度は紡糸性に直接影響す
るため、ポリマ溶液、すなわち紡糸原液として通常の紡
糸原液に比較してポリマ濃度を大幅に低くしなければな
らないが、このポリマ濃度の低下は、繊維構造を悪化ざ
ぜ、延伸または乾燥工程における単糸間の融着を助長し
、融着のないマルチフィラメントを製造することが極め
て困難である。また、ポリマ濃度の低下は溶媒回収の負
担を大きくするので工業的にも著しく不利である。However, this invention is based on the premise of using an AN-based polymer having an extremely high weight average molecular weight of 400,000, but such a polymer with a high degree of polymerization cannot be used, as disclosed in this publication. Special polymerization methods such as suspension polymerization in the presence of a dispersion stabilizer such as polyvinyl alcohol must be employed, which poses problems as an industrial production method in terms of polymer production costs, and the degree of polymerization is low. Due to the large size, the viscosity of the polymer solution is high and defoaming is difficult, and the viscosity of this polymer solution directly affects spinnability. However, this decrease in polymer concentration deteriorates the fiber structure and promotes fusing between single filaments during the drawing or drying process, making it extremely difficult to produce multifilaments without fusing. be. Furthermore, a decrease in polymer concentration increases the burden of solvent recovery, which is extremely disadvantageous from an industrial perspective.
特に、上記特開昭５９−１９９８０９号公報において好
ましい紡糸手段とされている乾・湿式紡糸法によって、
分子量４０万以上の高重合度ＡＮ系ポリマを紡糸する場
合には、モノフィラメントは問題ないとしても、マルチ
フィラメントを紡糸すると、上記紡糸原液のポリマ濃度
を低くせざるを得ないために、紡糸口金から吐出された
糸条の固化に時間を要し、単繊維相互間の融着が生じ易
いという問題がある。そして、この融着の発生は延伸工
程、特に延伸倍率を大きくし、高強度繊維を製造する場
合には、工業上品質、性能の安定した繊維糸条を製造す
る上で好ましくない毛羽、糸切れ発生の原因となる。In particular, by the dry/wet spinning method, which is considered as a preferable spinning method in the above-mentioned Japanese Patent Application Laid-Open No. 59-199809,
When spinning a high degree of polymerization AN-based polymer with a molecular weight of 400,000 or more, monofilament may not be a problem, but when spinning multifilament, the polymer concentration in the spinning stock solution must be lowered, so There is a problem in that it takes time for the discharged yarn to solidify, and fusion between single fibers tends to occur. The occurrence of this fusion occurs during the drawing process, especially when the drawing ratio is increased to produce high-strength fibers. cause the occurrence.
本発明者らは、商業的または工業的に入手または製造可
能な重合度を有するＡＮ系ポリマからなり、強度、弾性
率などの機械的性質全体が高度に改良、向上された、特
にタイヤコード、ロープ、魚網などの工業用としてはも
ちろん、前記の全芳香族ポリアミド繊維のように複合材
料の補強用繊維としても利用可能な超高強度ＡＮ系繊維
糸条およびその製造法について、鋭意検討を行って本発
明を見出したものである。The present inventors have developed a tire cord, in particular, which is made of an AN-based polymer having a degree of polymerization that is commercially or industrially obtainable or manufacturable, and whose overall mechanical properties such as strength and elastic modulus are highly improved and improved. We have been conducting intensive studies on ultra-high strength AN-based fiber yarns that can be used not only for industrial purposes such as ropes and fishing nets, but also as reinforcing fibers for composite materials like the fully aromatic polyamide fibers mentioned above, and methods for producing them. Thus, the present invention was discovered.
（発明の解決しようとする問題点）
すなわち、本発明の目的は、従来のＡＮ系繊維に比較し
て、その機械的強度が著しく改良、向上され、しかも商
業的または工業的に入手または製造可能な重合度を有す
るポリマから構成されているＡＮ系繊維糸条を提供する
にある。また他の目的は、このような高強度ＡＮ系繊維
糸条を工業的に有利に製造する方法を提供するにある。(Problems to be Solved by the Invention) In other words, the object of the present invention is to provide a fiber that is significantly improved and improved in mechanical strength compared to conventional AN-based fibers, and which is commercially or industrially obtainable or manufacturable. An object of the present invention is to provide an AN-based fiber yarn composed of a polymer having a high degree of polymerization. Another object of the present invention is to provide an industrially advantageous method for manufacturing such high-strength AN fiber threads.
（問題点を解決するための手段）
このような本発明の目的は、極限粘度が２．５以上、３
．６未満のアクリロニトリルを主成分とするアクリロニ
トリル系重合体からなり、少なくとも１０ａ ／ｄの引
張強度および１８０ａ／ｄ以上の初期弾性率を有する表
面が平滑な高強度アクリル系繊維糸条によって、基本的
に達成することができる。(Means for Solving the Problems) The object of the present invention is as follows:
．． Basically, a high-strength acrylic fiber yarn with a smooth surface, consisting of an acrylonitrile polymer whose main component is less than 6 acrylonitrile, and having a tensile strength of at least 10 a/d and an initial elastic modulus of 180 a/d or more, can be achieved.
本発明の特徴は、極限粘度で表示して２．５以上、３．
６未満という特定の値を有するＡＮ系ポリマを使用する
ことにあり、このような重合度範囲のＡＮ系ポリマを用
いることによってはじめて、繊維製造上の困難を回避し
て、機械的強度の極めて優れた単繊維間の融着のないＡ
Ｎ系繊維糸条を工業的に有利に製造することができるの
である。The characteristics of the present invention are that the intrinsic viscosity is 2.5 or more, and 3.
By using an AN-based polymer with a specific degree of polymerization of less than 6, difficulties in fiber production can be avoided and extremely high mechanical strength can be achieved. A with no fusion between single fibers
N-based fiber yarns can be produced industrially advantageously.
すなわち、本発明において、ＡＮ系ポリマの極限粘度が
２．５よりも小さくなると、本発明の目的とする高強度
繊維糸条が得られないが、極限粘度が３．６を越えると
きは、紡糸原液粘度の急激な増加をもたらし、紡糸が困
難となるため、ポリマ濃度を低下させざるを得ず、紡糸
原液のポリマ濃度を低下させると糸条形成後に多量の脱
溶媒を伴なうために、繊維構造が多孔化、失透しやすく
なり、かつ乾・湿式紡糸のように、紡糸原液が一旦空気
または不活性雰囲気中に吐出され、次いで凝固浴に導か
れて凝固が完了する紡糸手段を採用するときは、単糸間
の接着が生じ易くなるために、マルチフィラメントの製
造が難しい。That is, in the present invention, when the intrinsic viscosity of the AN-based polymer is lower than 2.5, the high-strength fiber yarn targeted by the present invention cannot be obtained, but when the intrinsic viscosity exceeds 3.6, spinning This causes a sudden increase in the viscosity of the spinning solution, making spinning difficult, so the polymer concentration has to be lowered.If the polymer concentration of the spinning solution is lowered, a large amount of solvent is removed after yarn formation. The fiber structure becomes porous and easily devitrified, and unlike dry/wet spinning, a spinning method is adopted in which the spinning stock solution is once discharged into air or an inert atmosphere, and then introduced into a coagulation bath to complete coagulation. When doing so, it is difficult to produce multifilaments because adhesion between single filaments tends to occur.
さらに、本発明のＡＮ系繊維糸条は、乾・湿式紡糸法に
よるために繊維表面が平滑であり、具体的にはその表面
の対比光沢度が少なくとも１０％、好ましくは１５〜３
０％の値を有する平滑な表面を有する点に特徴がある。Furthermore, the AN-based fiber yarn of the present invention has a smooth fiber surface due to the dry/wet spinning method, and specifically, the relative gloss of the surface is at least 10%, preferably 15 to 3.
It is characterized by a smooth surface with a value of 0%.
ここで繊維表面の光沢度は、次の測定方法によって求め
られる値であり、繊維表面の平滑性と同時に、繊維構造
の緻密性を反映する。Here, the glossiness of the fiber surface is a value determined by the following measurement method, and reflects both the smoothness of the fiber surface and the denseness of the fiber structure.
「表面光沢度の測定方法」
繊維束を平行に並べる。この時ケン縮を有する糸条は９
０〜１００℃の熱湯でケン縮を除きストレートな糸条と
する。この試料面に一方向から光線を与え、反射光を正
反射成分（ａ ）と拡散反射成分（ｂ ）とに分離し、
この両者の比を対比光沢度とする。``Method for measuring surface glossiness'' Arrange the fiber bundles in parallel. At this time, the yarn with crimp is 9
Remove shrinkage with hot water at 0 to 100°C to form a straight yarn. A light beam is applied to this sample surface from one direction, and the reflected light is separated into a specular reflection component (a) and a diffuse reflection component (b),
The ratio between the two is defined as the contrast gloss level.
対比光沢度−（１−ｂ／ａ）ｘ１００
本発明のＡＮ系繊維糸条は、他の汎用合成繊維のポリア
ミドやポリエステル系繊維のように、ポリマをそのまま
溶融紡糸するのではなくて、通常ポリマを各種の溶剤に
溶解し、このポリマを溶剤に溶解した溶液を紡糸ドープ
として使用し、湿式、乾式あるいは乾・湿式紡糸などの
手段を採用して繊維化されるが、このような手段を採用
する場合には、繊維中に含まれる溶媒を除去すること（
脱溶媒）が必要である。この脱溶媒は通常水を用いて行
われるが、脱溶媒に対応して繊維の容積収縮が追随でき
ないためボイドを生成する。このボイドをなくすため乾
燥緻密化が行なわれるが、繊維学会誌Ｖｏｌ、２９．Ｎ
ｏ 、８ （１９７３）（、：示されているように、ポ
リマ濃度が低くなるとボイドの多い凝固糸が得られるた
め乾燥工程を経てもボイドが消失しにくく、強伸度的性
質も低いものとなる。Comparative gloss - (1-b/a) x 100 The AN-based fiber yarn of the present invention is not made by melt-spinning the polymer as it is, unlike other general-purpose synthetic fibers such as polyamide and polyester fibers, but by melt-spinning the polymer as it is. The polymer is dissolved in various solvents, and the solution of this polymer dissolved in the solvent is used as a spinning dope, and fibers are produced by wet, dry, or dry/wet spinning. If so, remove the solvent contained in the fibers (
(Desolvation) is required. This desolvation is usually performed using water, but voids are generated because the volumetric shrinkage of the fibers cannot keep up with the desolvation. In order to eliminate these voids, drying and densification is performed. N
o, 8 (1973) (,: As shown, when the polymer concentration is low, a coagulated fiber with many voids is obtained, so the voids are difficult to disappear even after the drying process, and the strength and elongation properties are also low. Become.
一方、重合度を高めることはポリマを溶媒に溶解した時
の原液粘度が高くなることになり、原液の安定性、曳糸
性の点から、ポリマ濃度を低下させざるを得ない。した
がって重合度の高いポリマではポリマ濃度の低下による
悪影響のため緻密化が回能となり、必ずしも高強度糸が
得られない。On the other hand, increasing the degree of polymerization increases the viscosity of the stock solution when the polymer is dissolved in a solvent, so that the polymer concentration must be lowered from the standpoint of stability and spinnability of the stock solution. Therefore, in the case of a polymer with a high degree of polymerization, densification becomes a chore due to the negative effect of a decrease in polymer concentration, and high-strength yarns cannot necessarily be obtained.
すなわち、本発明になるＡＮ系繊維糸条の特徴は、極限
粘度が２．５以上、３．６未満、好ましくは２．８〜３
．５、さらに好ましくは２．９〜３．３という特定の重
合度を有するＡＮ系ポリマから構成されており、このよ
うな特定の重合度を有するＡＮ系ポリマを後述する乾・
湿式紡糸という特定の紡糸プロセスおよび条件を適用し
て繊維化し、機械的強度、たとえば引張強度が１０！Ｉ
Ｉ／ｄ１好ましくは１２ｏ／ｄ以上、ループ強度４゜０
０／ｄ以上、好ましくは５．０ｇ／ｄ以上と言う卓越し
た物性を有する繊維糸条を形成せしめた点にある。That is, the characteristic of the AN-based fiber yarn according to the present invention is that the intrinsic viscosity is 2.5 or more and less than 3.6, preferably 2.8 to 3.
．． 5. More preferably, it is composed of an AN-based polymer having a specific degree of polymerization of 2.9 to 3.3, and the AN-based polymer having such a specific degree of polymerization is
A specific spinning process and conditions called wet spinning are applied to form fibers, and the mechanical strength, for example, tensile strength, is 10! I
I/d1 preferably 12o/d or more, loop strength 4゜0
The point is that fiber threads having excellent physical properties of 0/d or more, preferably 5.0 g/d or more are formed.
また、本発明の繊維糸条は、その表面が光沢度で表示し
て少なくとも１０％以上、通常１５〜３０％の範囲の高
い対比光沢度を有しているから、表面の欠陥が少なく、
加えて繊維の緻密性に優れているので、高強度高弾性率
でしかも曲げや摩擦に対しても強い繊維糸条が得られる
。In addition, the fiber yarn of the present invention has a high relative gloss level of at least 10% or more, usually in the range of 15 to 30%, as expressed in terms of gloss level, so there are few defects on the surface.
In addition, since the fibers have excellent density, it is possible to obtain fiber yarns that have high strength, high modulus of elasticity, and are resistant to bending and friction.
上記のような優れた物性、性能を有する本発明の繊維糸
条の製造方法としては、前
述したように、繊維を構成するポリマの重合度が極限粘
度で表示して２．５以上３．６未満という特定の範囲内
にあるポリマを繊維軸方向に高度に配向させる必要があ
る。As described above, the method for producing the fiber yarn of the present invention having the above-mentioned excellent physical properties and performance is such that the degree of polymerization of the polymer constituting the fiber is 2.5 or more and 3.6 as expressed by the intrinsic viscosity. It is necessary that the polymer be highly oriented in the fiber axis direction within a certain range of less than or equal to
本発明者らの検討によると、このような高配向のＡＮ系
繊維糸条は、アクリル系繊維の製造方法として最も広く
工業的に採用されている湿式あるいは乾式紡糸方法によ
っては製造が困雌であり、以下に詳述する乾・湿式紡糸
法、すなわちＡＮ系ポリマをその溶剤に溶解して得られ
た紡糸溶液を紡糸口金孔を通して一旦空気もしくは不活
性気体、このましくは空気中に吐出し、この吐出糸条を
気体の微小空間を経由して凝固液浴中に導き、凝固せし
める方法を採用し、ざらに特定の製造プロセスおよびそ
の条件を採用することによってはじ 、めで、可能であ
ることが見出されたのである。According to the studies of the present inventors, it is difficult to manufacture such highly oriented AN-based fiber yarns using wet or dry spinning methods, which are the most widely used industrial methods for manufacturing acrylic fibers. There is a dry/wet spinning method described in detail below, that is, a spinning solution obtained by dissolving an AN-based polymer in its solvent is once discharged into air or an inert gas, preferably air, through a spinneret hole. By adopting a method in which this discharged thread is guided into a coagulating liquid bath via a gas microscopic space and coagulating it, and by adopting a roughly specific manufacturing process and its conditions, this is possible. was discovered.
以下、本発明になる高強度ＡＮ系繊維糸条の製造方法に
ついて詳細に説明する。Hereinafter, the method for producing the high-strength AN-based fiber yarn according to the present invention will be explained in detail.
まず、本発明に用いられるＡＮ系ポリマは、ＡＮを少く
とも９０モル％、好ましくは９５〜１００モル％と該Ａ
Ｎに対して共重合性を有するビニル化合物５モル％以下
、好ましくは０〜５モル％とからなるＡＮホモポリマも
しくはＡＮ系共重合体（以下、ＡＮコポリマという）で
あり、ビニル化合物の共重合割合が５モル％を越えると
、得られる繊維表面の耐熱性および緻密性が低下し、本
発明の目的達成の上で好ましくない。First, the AN-based polymer used in the present invention contains at least 90 mol% of AN, preferably 95 to 100 mol%.
AN homopolymer or AN copolymer (hereinafter referred to as AN copolymer) consisting of 5 mol% or less, preferably 0 to 5 mol%, of a vinyl compound having copolymerizability with N, and the copolymerization ratio of the vinyl compound If it exceeds 5 mol%, the heat resistance and denseness of the resulting fiber surface will decrease, which is not preferable in terms of achieving the object of the present invention.
上記ビニル化合物としては、公知の各種ＡＮに対して共
重合性を有する化合物であればよく、特に限定されない
が、好ましい共重合成分としては、アクリル酸、イタコ
ン酸、アクリル酸メチル、メタクリル酸メチル、酢酸ビ
ニル、アリルスルホン酸ソーダ、メタリルスルホン酸ソ
ーダ、ｐ−スチレンスルホン酸ソーダなどを例示するこ
とができる。The vinyl compound is not particularly limited as long as it is a compound that is copolymerizable with various known ANs, but preferred copolymerizable components include acrylic acid, itaconic acid, methyl acrylate, methyl methacrylate, Examples include vinyl acetate, sodium allylsulfonate, sodium methallylsulfonate, and sodium p-styrenesulfonate.
このようなＡＮ系ポリマは、その溶剤、たとえばジメチ
ルスルホキシド（ＤＭＳＯ）、ジメチルホルムアミド（
ＤＭＡ）、ジメチルアセトアミド（ＤＭＡＣ）、エチレ
ンカーボネート、ブチルラクトンなどの有機溶剤、塩化
亜鉛、塩化力ルシュウム、リチュウムブロマイド、チオ
シャン化ナトリウムなどの水溶性無機塩の濃厚水溶液に
溶解し、得られたポリマ溶液が紡糸原液、すなわち紡糸
ドープとして使用される。Such AN-based polymers can be used in solvents such as dimethyl sulfoxide (DMSO), dimethyl formamide (
DMA), dimethylacetamide (DMAC), ethylene carbonate, organic solvents such as butyllactone, and concentrated aqueous solutions of water-soluble inorganic salts such as zinc chloride, lucium chloride, lithium bromide, and sodium thiocyanide, resulting in a polymer solution. is used as a spinning stock solution, that is, a spinning dope.
しかしながら、この紡糸原液のポリマ濃度は、約５〜２
０重量％、好ましくは１０〜１８％の範囲内のものがよ
く、ポリマ濃度が５％よりも低くなると、繊維の緻密性
が悪くなるため強伸度的性質が低下するし、製造コスト
面でも不利になるために好ましくないし、ポリマ濃度が
２０％を越えると、原液粘度が高くなりすぎ原液の安定
性および曳糸性が悪くなるために好ましくない。However, the polymer concentration of this spinning stock solution is approximately 5 to 2
0% by weight, preferably within the range of 10 to 18%. If the polymer concentration is lower than 5%, the density of the fibers will deteriorate, resulting in a decrease in strength and elongation properties, and also in terms of manufacturing cost. This is not preferred because it is disadvantageous, and if the polymer concentration exceeds 20%, the viscosity of the stock solution becomes too high and the stability and spinnability of the stock solution deteriorates, which is not preferable.
また、紡糸原液粘度は４５℃の粘度で少なくとも１５０
０ポイズ、好ましくは２０００ポイズ以上必要であり、
ざらに好ましくは３０００〜１０゜ＯＯＯボイズがよい
。４５℃における原液粘度が１５００ポイズ未満では凝
固構造が悪化するため強度が低下する。
。In addition, the viscosity of the spinning dope is at least 150 at 45°C.
0 poise, preferably 2000 poise or more is required,
The roughness is preferably 3000 to 10° OOO voids. If the viscosity of the stock solution at 45° C. is less than 1500 poise, the coagulation structure deteriorates and the strength decreases.
.
そしてこの紡糸原液濃度は、本発明に採用する乾・湿式
紡糸法においては、極めて重要であり、上記紡糸原液の
ポリマ濃度および粘度が上記範囲内にあるときにはじめ
て、乾・湿式紡糸によってドリップ、糸切れなどのトラ
ブルを生ずることなく、安定に紡糸でき、かつ高強度高
弾性率の繊維糸条を得ることが可能になるのである。The concentration of this spinning stock solution is extremely important in the dry/wet spinning method employed in the present invention, and only when the polymer concentration and viscosity of the spinning stock solution are within the above ranges will drip or This makes it possible to stably spin the fibers without causing problems such as yarn breakage, and to obtain fiber yarns with high strength and high elastic modulus.
紡糸原液の温度は、０℃よりも低温になる原液濃度が高
くなり、ゲル化しやすく紡糸が困難になるとという欠点
があり、１３０℃よりも高温になると溶媒や原液の安定
性が不良になる等の欠点があるので、通常３０〜１００
℃の範囲内に保持するのがよい。When the temperature of the spinning stock solution is lower than 0℃, the concentration of the solution becomes high, and it tends to gel, making spinning difficult.If the temperature of the spinning stock solution is lower than 130℃, the stability of the solvent and stock solution becomes poor, etc. Usually 30 to 100
It is best to keep it within the range of ℃.
かくして調整された紡糸原液は、乾・湿式紡糸されるが
、この場合の紡糸口金面と凝固浴液面との間の距離は約
１〜２０ｍｍ、好ましくは２〜１０關の範囲内に設定す
るのがよく、１ｍｍよりも小さくなると口金面が液面と
接触する等の問題を生じやすくなるため好ましくないし
、２０ｍｆｌｌを越えると、吐出糸条の糸切れおよび単
糸間接着が発生し易くなるため好ましくない。The spinning solution prepared in this way is subjected to dry/wet spinning, and in this case, the distance between the spinneret surface and the coagulation bath liquid level is set within a range of about 1 to 20 mm, preferably 2 to 10 mm. If it is smaller than 1 mm, problems such as the mouth surface coming into contact with the liquid surface are likely to occur, which is undesirable. If it exceeds 20 mfl, thread breakage of the discharged yarn and adhesion between single yarns are likely to occur. Undesirable.
このような乾・湿式紡糸において、紡糸原液の吐出量と
吐出糸条の引取り速度で定まる紡糸ドラフトは、上記口
金面と凝固浴液面との間の距離と同様に該ドラフトが大
きすぎると、糸切れなどを生じ易くなるし、該ドラフト
が低くすぎると、単繊維間の融着、糸むらの原因になる
ため、好ましくは該紡糸ドラフトを０．１〜１．５、好
ましくは０．２〜０．８の範囲内にするのがよい。In such dry/wet spinning, the spinning draft, which is determined by the discharge amount of the spinning dope and the take-up speed of the discharged yarn, is similar to the distance between the spinneret surface and the coagulation bath surface, and if the draft is too large. If the draft is too low, it may cause fusion between single fibers and yarn unevenness, so it is preferable to set the spinning draft to 0.1 to 1.5, preferably 0. It is preferable to set it within the range of 2 to 0.8.
また、凝固浴としては、公知のＡＮ系繊維の湿式または
乾・湿式紡糸に使用される水もしくは前述したＡＮ系ポ
リマの溶剤の水溶液、たとえば濃度が１０〜８０重量％
および温度が０〜３５℃の溶剤水溶液がが用いられる。The coagulation bath may be water used in known wet or dry/wet spinning of AN-based fibers or an aqueous solution of the above-mentioned AN-based polymer solvent, for example, at a concentration of 10 to 80% by weight.
and an aqueous solvent solution having a temperature of 0 to 35°C.
かくして得られた凝固糸条には、従来公知の後処理、す
なわち水洗、延伸、乾燥などの処理が施されるが、本発
明においては、乾燥、緻密化した後の繊維糸条に次に詳
述する乾熱延伸、すなわち、加熱空気を供給、排出する
ことができるチューブ状の加熱筒を使用し、所定の温度
に保たれた該加熱筒中に糸条を通過させながら延伸する
手段を適用して延伸することが必要であり、乾・湿式紡
糸したＡＮ系繊維糸条をこの乾熱延伸することによって
はじめて、極限粘度少くとも２．５以上、３゜６未満の
ＡＮ系ポリマかうなり、繊維表面が平滑で、単繊維相互
間に実質的に融着のない高強度繊維糸条に転換すること
が可能になるのである。The thus obtained coagulated yarn is subjected to conventionally known post-treatments such as water washing, stretching, and drying, but in the present invention, the fiber yarn after drying and densification is subjected to the following detailed treatment. In the dry heat drawing described above, a method is applied in which a tubular heating cylinder capable of supplying and discharging heated air is used, and the yarn is stretched while passing through the heating cylinder maintained at a predetermined temperature. It is necessary to draw the AN-based polymer with an intrinsic viscosity of at least 2.5 or more and less than 3°6 by dry-heat-drawing the dry/wet-spun AN-based fiber yarn. It becomes possible to convert the fiber into a high-strength fiber yarn with a smooth surface and substantially no fusion between single fibers.
すなわち、本発明における乾熱延伸は、まず凝固後、約
２〜１０倍、好ましくは４〜８倍に一次延伸された糸条
を乾燥、緻密化後、凝固繊維糸条の原長当り少くとも１
０倍に乾熱二次延伸することが必要である。That is, in the dry heat drawing in the present invention, first, after coagulating, the filament which has been primarily drawn by approximately 2 to 10 times, preferably 4 to 8 times, is dried and densified, and then at least per original length of the coagulated fiber yarn is 1
It is necessary to perform dry heat secondary stretching to 0 times.
また、この乾熱二次延伸は、ＨＪ／ｄ以上、好ましくは
１．５〜２．０ｇ／ｄの延伸張力発現下に、１６０〜２
５０℃の加熱空中で延伸するのがよい。−次延伸倍率が
２倍未満では緻密な乾燥糸が得られないため好ましくな
いし、１０倍を越えると乾燥時に接着を生じ易く好まし
くない。In addition, this dry heat secondary stretching is performed under a stretching tension of HJ/d or more, preferably 1.5 to 2.0 g/d, and
It is preferable to stretch in air heated at 50°C. - If the subsequent stretching ratio is less than 2 times, dense dry yarn cannot be obtained, which is not preferable, and if it exceeds 10 times, adhesion tends to occur during drying, which is not preferable.
ここで、上記乾熱延伸は、本発明の上述した特定極限粘
度、すなわち分子量を有するＡＮ系ポリマの高分子鎖を
繊維軸方向に高度に配向させる重要な手段であり、他の
延伸糸手段の場合には延伸倍率を大きくすると破壊を伴
った延伸になるため好ましくない。Here, the above-mentioned dry heat drawing is an important means of highly orienting the polymer chains of the AN-based polymer having the above-mentioned specific intrinsic viscosity, that is, molecular weight, in the fiber axis direction, and is an important means for highly orienting the polymer chains of the AN-based polymer having the above-mentioned specific intrinsic viscosity, that is, molecular weight, in the fiber axis direction. In such cases, increasing the stretching ratio is not preferable because the stretching may be accompanied by destruction.
また、該乾熱延伸の温度範囲が１５０℃よりも低くなる
と、十分な延伸倍率が得られないために好ましくないし
、他方、２５０℃を越えると繊維の耐熱性の不足に基づ
く延伸性の低下を伴なうために好ましくない。In addition, if the temperature range of the dry heat stretching is lower than 150°C, it is not preferable because a sufficient stretching ratio cannot be obtained, and on the other hand, if it exceeds 250°C, the drawability may decrease due to the lack of heat resistance of the fiber. Undesirable because it accompanies it.
乾熱延伸手段としては、熱ドラム、熱板、熱チユーブな
ど、好ましくは熱らむまたは熱ドラムと熱チユーブ（加
熱空気を供給、排出することができるチューブ状の加熱
筒）とを組み合わせて乾熱下に延伸する手段を使用する
のがよい。Dry heat stretching means include a heat drum, a hot plate, a heat tube, etc., preferably a heat drum, or a combination of a heat drum and a heat tube (a tubular heating tube capable of supplying and discharging heated air). It is preferable to use a means of stretching downward.
この乾熱延伸における延伸倍率は、乾熱延伸に供される
糸条の延伸の履歴によって異り、最終的に得られる延伸
糸条の全部延伸倍率が少くとも１０倍、好ましくは１３
〜２５倍になる範囲内で設定される。たとえば、乾・湿
式紡糸し、水洗後、約４〜８倍に一次延伸を施されてい
る糸条の場合には、１．５〜４倍の乾熱延伸が施される
し、このような延伸が施されていない糸条の場合には、
乾熱延伸を一段または多段に行うことによって、上記全
延伸倍率が１０〜２５倍好ましくは１５〜２０倍になる
ように延伸される。The draw ratio in this dry heat drawing varies depending on the drawing history of the yarn subjected to dry heat drawing, and the total draw ratio of the finally obtained drawn yarn is at least 10 times, preferably 13 times.
It is set within a range of ~25 times. For example, in the case of a yarn that has been dry-spun and wet-spun, washed with water, and then subjected to primary stretching of approximately 4 to 8 times, it is subjected to dry heat stretching of 1.5 to 4 times. In the case of yarn that has not been stretched,
By performing dry heat stretching in one stage or in multiple stages, the above-mentioned total stretching ratio is 10 to 25 times, preferably 15 to 20 times.
このようにして得られる本発明のＡＮ系繊維糸条は、単
繊維繊度が３デニール（ｄ ＞以下、好ましくは２ｄ以
下のマルチフィラメントであり、前述したように、高配
向性を有し、引張強度をはじめとする機械的性質におい
て卓越した高強度を有する。しかも繊維構造は極めて緻
密で、繊維の表面も平滑性に富み、表面欠陥の少い単繊
維相互間に実質的に融着かないというメリットを有する
から、工業用または産業用、繊維強化用として多くの分
野、具体的にはキャンパス、アスベスト代替、縫糸、ホ
ース、重布などにの工業用として、さらには複合材料の
補強用繊維として使用することが可能である。The AN-based fiber yarn of the present invention thus obtained is a multifilament with a single fiber fineness of 3 deniers (d > or less, preferably 2 d or less), and as described above, has high orientation and tensile strength. It has excellent strength and other mechanical properties.Moreover, the fiber structure is extremely dense, the fiber surface is smooth, and there is virtually no fusion between single fibers with few surface defects. Because of its merits, it is used in many fields for industrial use and fiber reinforcement, specifically for canvas, asbestos substitutes, sewing threads, hoses, heavy fabrics, etc., and even as reinforcing fibers for composite materials. It is possible to use.
以下、実施例により本発明の効果をざらに具体的に説明
する。EXAMPLES Hereinafter, the effects of the present invention will be explained in detail using Examples.
なお、以下の実施例ならびに比較例において、ポリマの
極限粘度は
Ｊｏｕｒｎａｌ ｏｆ Ｐｏｌｙｍｅｒ ５ｃｉｅｎｃ
ｅ（＾−１）第６巻、第１４７〜１５７頁（１９６８年
）に記載されている測定法に準じて、ジメチルホルムア
ミド（ＤＭＦ＞を溶剤に使用し、３０℃で測定した値で
ある。In addition, in the following Examples and Comparative Examples, the intrinsic viscosity of the polymer is determined from the Journal of Polymer 5cienc.
The value was measured at 30° C. using dimethylformamide (DMF) as a solvent according to the measurement method described in e(^-1) Vol. 6, pp. 147-157 (1968).
実施例１〜２ 比較例１〜８
１００％のＡＮをＤＭＳＯ中で溶液重合し、極限粘度が
それぞれ１．５．２．８．３．３．３゜９、および１２
．７である５種類のＡＮ系ポリマを作成した。Examples 1-2 Comparative Examples 1-8 100% AN was solution polymerized in DMSO, and the intrinsic viscosities were 1.5, 2, 8, 3, 3, 3, 9, and 12, respectively.
．． Five types of AN-based polymers were prepared.
これらの５種類のポリマをその溶液の粘度（η４５℃）
がそれぞれ約３，０００ポイズになるように調整し、紡
糸原液を作成した。得られた５種類第１表
紡糸方法 極限粘度 強度 ヤング率 ループ強慣 単
糸閣法： ０は接着なし、Δは接着あり、×は接着が多
いことをそれぞれ示す。The viscosity of the solution of these five types of polymers (η45℃)
were each adjusted to about 3,000 poise to prepare a spinning dope. The five types obtained Table 1 Spinning method Intrinsic viscosity Strength Young's modulus Loop tenacity Single thread method: 0 indicates no adhesion, Δ indicates adhesion, and × indicates a large amount of adhesion.
作成した。Created.
の紡糸原液を用いて、１．０００ホールの紡糸口金を用
いて湿式および乾・湿式紡糸の二つの方法で紡糸した。Using the spinning dope, spinning was carried out using a 1,000-hole spinneret by two methods: wet spinning and dry/wet spinning.
いずれの紡糸法においても凝固浴には、２０℃の５５％
ＤＭＳＯ水溶液を使用した。In either spinning method, the coagulation bath contains 55%
A DMSO aqueous solution was used.
乾・湿式紡糸の場合、紡糸口金面と凝固浴液面との距離
は５ｍｍに設定し、凝固浴液面から集束ガイドまでの距
離は４００ｍ１ｌｌに設定した。In the case of dry/wet spinning, the distance between the spinneret surface and the coagulation bath liquid level was set to 5 mm, and the distance from the coagulation bath liquid level to the focusing guide was set to 400 ml.
得られた未延伸糸条を水洗後、熱水中で５倍延伸し、油
剤を付与した侵、１３０℃で乾燥・緻密化した。次いで
１８０〜２００℃の温度雰囲気の乾熱チューブ中で延伸
し、最高延伸倍率が９０％の延伸糸条をサンプリングし
、その単糸の繊維物性を測定した。結果を第１表に示し
た。The obtained undrawn yarn was washed with water, then stretched 5 times in hot water, soaked with an oil agent, and dried at 130° C. to make it densified. Next, the fibers were drawn in a dry heat tube at a temperature of 180 to 200° C., and the drawn yarns with a maximum draw ratio of 90% were sampled, and the fiber properties of the single yarns were measured. The results are shown in Table 1.
また、実施例１および２の対比光沢度は、それぞれ２０
．３％および２２．５％であり、いずれも比較例４〜８
の対比光沢度３〜６％に比較して高い値を示した。In addition, the comparative glossiness of Examples 1 and 2 was 20
．． 3% and 22.5%, both of which are Comparative Examples 4 to 8.
It showed a higher value compared to the contrast gloss of 3 to 6%.
Claims (5)
トリルを主成分とするアクリロニトリル系重合体からな
り、少なくとも１５ｇ／ｄの引張強度、１８０ｇ／ｄ以
上の初期弾性率および４．０以上のループ強度を有する
表面が平滑な高強度アクリル系繊維糸条。(1) Consisting of an acrylonitrile polymer mainly composed of acrylonitrile with an intrinsic viscosity of 2.5 or more and less than 3.6, having a tensile strength of at least 15 g/d, an initial elastic modulus of 180 g/d or more, and 4.0 or more. A high-strength acrylic fiber yarn with a smooth surface and a loop strength of .
ル系重合体の極限粘度が２．８〜３．５の範囲内であり
、表面平滑性が対比光沢度で表示して少くとも１０％で
ある高強度アクリル系繊維糸条。(2) In claim 1, the acrylonitrile polymer has an intrinsic viscosity within the range of 2.8 to 3.5, and a surface smoothness of at least 10% expressed in terms of relative gloss. High strength acrylic fiber yarn.
トリル系重合体が約９５モル％以上のアクリロニトリル
と約５モル％以下の該アクリロニトリルに対して共重合
性を有するビニル化合物とからなる極限粘度が２．９〜
３．３の範囲内のアクリロニトリル系共重合体であり、
引張り強度がが少くとも１７ｇ／ｄ、引張弾性率が約２
００ｇ／ｄ以上およびループ強度が５．０ｇ／ｄ以上で
ある高強度アクリル系繊維糸条。(3) In claims 1 and 2, the acrylonitrile polymer has an intrinsic viscosity of about 95 mol% or more of acrylonitrile and about 5 mol% or less of a vinyl compound copolymerizable with the acrylonitrile. is 2.9 ~
An acrylonitrile copolymer within the range of 3.3,
Tensile strength of at least 17 g/d, tensile modulus of approximately 2
A high-strength acrylic fiber yarn having a loop strength of 00 g/d or more and a loop strength of 5.0 g/d or more.
が５〜２０重量％、４５℃の溶液粘度が１５００〜１０
，０００ポイズであるアクリロニトリル系重合体溶液を
紡糸口金孔を通して一旦空気あるいは不活性気体中に吐
出させた後、凝固浴中に導いて凝固させ、得られた凝固
繊維糸条を水洗後または水洗と同時に、２〜１０倍に延
伸し、乾燥、緻密化の処理を施し、次いで温度が１８０
〜２４０℃の乾熱下で１．２〜５倍に延伸することを特
徴とする高強度アクリル系繊維糸条の製造法。(4) Intrinsic viscosity is 2.5 or more and less than 3.6, polymer concentration is 5 to 20% by weight, and solution viscosity at 45°C is 1500 to 10
,000 poise is once discharged into air or an inert gas through a spinneret hole, and then introduced into a coagulation bath and coagulated, and the obtained coagulated fiber thread is washed with water or after washing with water. At the same time, it is stretched 2 to 10 times, dried and densified, and then heated to 180℃.
A method for producing high-strength acrylic fiber yarn, which comprises stretching 1.2 to 5 times under dry heat at ~240°C.
０．１〜１．５の範囲内であり、紡糸口金面と凝固浴液
面との距離が１〜２０ｍｍである高強度アクリル系繊維
糸条の製造法。(5) In claim 4, the high-strength acrylic fiber has a spinning draft in the range of 0.1 to 1.5 and a distance between the spinneret surface and the coagulation bath liquid level of 1 to 20 mm. Yarn manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27317184A JPS61152811A (en) | 1984-12-26 | 1984-12-26 | High tenacity acrylic fiber yarn and production thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27317184A JPS61152811A (en) | 1984-12-26 | 1984-12-26 | High tenacity acrylic fiber yarn and production thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61152811A true JPS61152811A (en) | 1986-07-11 |
Family
ID=17524085
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27317184A Pending JPS61152811A (en) | 1984-12-26 | 1984-12-26 | High tenacity acrylic fiber yarn and production thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61152811A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6233817A (en) * | 1985-08-05 | 1987-02-13 | Japan Exlan Co Ltd | Production of acrylic fiber having high tenacity and modulus |
| EP0255109A2 (en) * | 1986-07-28 | 1988-02-03 | Mitsubishi Rayon Co., Ltd. | Process for producing an acrylic fiber having high fiber characteristics |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5381724A (en) * | 1976-12-24 | 1978-07-19 | Asahi Chem Ind Co Ltd | Production of acrylic synthetic fibers |
| JPS5751810A (en) * | 1980-07-23 | 1982-03-26 | Hoechst Ag | High module polyacrylonitrile yarn , fiber and method |
| JPS57161117A (en) * | 1981-03-20 | 1982-10-04 | Hoechst Ag | Set polyacrylonitrile filament and fiber and production thereof |
| JPS59199809A (en) * | 1983-04-20 | 1984-11-13 | Japan Exlan Co Ltd | Polyacrylonitrile yarn having high strength and its preparation |
-
1984
- 1984-12-26 JP JP27317184A patent/JPS61152811A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5381724A (en) * | 1976-12-24 | 1978-07-19 | Asahi Chem Ind Co Ltd | Production of acrylic synthetic fibers |
| JPS5751810A (en) * | 1980-07-23 | 1982-03-26 | Hoechst Ag | High module polyacrylonitrile yarn , fiber and method |
| JPS57161117A (en) * | 1981-03-20 | 1982-10-04 | Hoechst Ag | Set polyacrylonitrile filament and fiber and production thereof |
| JPS59199809A (en) * | 1983-04-20 | 1984-11-13 | Japan Exlan Co Ltd | Polyacrylonitrile yarn having high strength and its preparation |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6233817A (en) * | 1985-08-05 | 1987-02-13 | Japan Exlan Co Ltd | Production of acrylic fiber having high tenacity and modulus |
| EP0255109A2 (en) * | 1986-07-28 | 1988-02-03 | Mitsubishi Rayon Co., Ltd. | Process for producing an acrylic fiber having high fiber characteristics |
| EP0255109A3 (en) * | 1986-07-28 | 1989-08-23 | Mitsubishi Rayon Co. Ltd. | Process for producing an acrylic fiber having high fiber characteristics |
| US4902452A (en) * | 1986-07-28 | 1990-02-20 | Mitsubishi Rayon Co., Ltd. | Process for producing an acrylic fiber having high fiber characteristics |
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