JPS60167918A - Method for drawing high-tenacity polyethylene fiber - Google Patents

Abstract

PURPOSE:To obtain the titled fibers having a very high strength and modulus, by spinning a solution containing a specific amount of polyethylene having a high weight-average molecular weight, and drawing the resultant undrawn fibers with a heater between a pair of rollers under specific conditions in one stage. CONSTITUTION:A solution containing 4-12wt% polyethylene having >=800,000 weight-average molecular weight in a solvent, e.g. decalin, is extruded through a spinnert into fibers, which are then dried in a hot air drayer to afford undrawn fibers with <=100wt%, based on the polyethylene, solvent content. The resultant undrawn fibers are then drawn with a heater between a pair of sollers under conditions to set the length of the heater to hold the relation of the formula [L is the length of the heater (m); HD is the draw ratio (times); V1 is the feed speed (m/min); T is the average temperature of the heater ( deg.C); HD>=20; 0.1<=V1<=10; 110<=T<=150] at >=20 draw ratio in one stage to give the aimed fibers.

Description

【発明の詳細な説明】 本発明は、引張強度ならびにモジュラスのきわめて大き
なポリエチレン繊維を製造するための延伸方法に関する
ものであり、とくに操業性を向上させるために延伸速度
を大きくしても高倍率にて延伸できる方法に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drawing method for producing polyethylene fibers with extremely high tensile strength and modulus.In particular, in order to improve operability, even if the drawing speed is increased, the drawing ratio can be increased. The present invention relates to a method that allows for stretching.

一般に、ポリマーの分子鎖末端は繊維微細構造上の欠陥
部となるために分子量の大きいポリマーはど単位体積当
りの分子鎖末端が少なく、大きな強度が発現することが
期待されている。しかしながら超高分子量ポリエチレン
を紡糸する場合は高い溶融粘性のために溶融紡糸するこ
とは困難であり、そのため通常、超高分子量ポリエチレ
ンを溶剤に溶解した希薄溶液を用いて紡糸時に冷却固化
する、いわゆるゲル紡糸法が採用されている。そして、
この方法で得られた紡糸原糸の微細構造は、折りたたみ
分子鎖部分（ｆｏｌｄｅｄ　ｃｈａｉｎ）と分子鎖から
み部分（ｔｉｅ　ｍｏｌｅｃｕｌｅ　）とからなるラメ
ラ構造をとっているとみなされており、これを非常にゆ
つくシと高倍率で延伸して分子鎖を伸ばして高度に配向
結晶化させることによって高強力で高モジュラスのポリ
エチレン繊維が得られることが周知である。In general, the molecular chain ends of a polymer become defects in the fiber microstructure, so polymers with a large molecular weight have fewer molecular chain ends per unit volume and are expected to exhibit great strength. However, when spinning ultra-high molecular weight polyethylene, it is difficult to perform melt-spinning due to its high melt viscosity. Therefore, a dilute solution of ultra-high molecular weight polyethylene in a solvent is usually used, which is cooled and solidified during spinning. The spinning method is used. and,
The fine structure of the spun filament obtained by this method is considered to have a lamellar structure consisting of folded chain portions and tie molecules, and this is It is well known that polyethylene fibers with high strength and high modulus can be obtained by stretching the molecular chains at a slow rate and at a high magnification, resulting in highly oriented crystallization.

超高分子量ポリエチレン繊維を高倍率に延伸する場合、
繊維学会誌、第５５巻、２月号、第５７〜６５頁（１９
７７）に記載されている如く２つの変形機構が考えられ
る。すなわち、１つはｔｉｅｍｏ−１ｅｃｕｌｅによっ
て折りたたみ結晶内から折りたたみ分子鎖が引き伸ばさ
れる機構と、もう１つは延伸時に生成した伸長分子鎖の
結晶（ｔｉｅ　１ｉｎｋ）が折シたたみ結晶とともに破
壊されて変形する機構である。延伸速度が小さい場合は
主として前者の延伸機構が考えられ、折りたたみ結晶の
破壊（ｕｎｆｏｌｄ−ｉｎｇ）によって生成した伸長分
子鎖の結晶（ｔｉｅ　１ｉｎｋ）が集合して強大で完全
なものとなり、その結果、ｔｉｅ　１ｉｎｋの破壊が起
こり難く、低延伸張力で高倍率に延伸できる。一方、延
伸速度が大きい場合は後者の延伸機構が考えられ、折り
たたみ分子鎖が伸長されると同時に延伸で生成した伸長
分子鎖による不完全結晶の破壊が起こる。その結果、延
伸張力は高くなり、繊維微細構造に欠陥部があると、そ
こに応力集中が生じて繊維は切断され易く、ひいては延
伸倍率の低下を招く。When drawing ultra-high molecular weight polyethylene fibers to a high magnification,
Journal of the Japan Textile Society, Vol. 55, February issue, pp. 57-65 (19
There are two possible deformation mechanisms as described in 77). That is, one mechanism is that the folded molecular chain is stretched from within the folded crystal by tiemo-1 ecule, and the other is that the crystal of the stretched molecular chain (tie 1 ink) generated during stretching is destroyed and deformed together with the folded crystal. It is a mechanism. When the stretching speed is low, the former stretching mechanism is mainly considered, and the crystals (tie 1 ink) of extended molecular chains generated by unfolding of folded crystals aggregate to become strong and complete, and as a result, Tie 1 ink is less likely to break and can be stretched to a high magnification with low stretching tension. On the other hand, when the stretching speed is high, the latter stretching mechanism is considered, and at the same time the folded molecular chains are stretched, the incomplete crystals are destroyed by the stretched molecular chains generated by the stretching. As a result, the drawing tension becomes high, and if there is a defect in the fiber microstructure, stress concentration occurs there and the fiber is likely to be cut, which in turn leads to a decrease in the drawing ratio.

したがって、操業性向上をねらいとして高速で延伸倍率
を高くするためには、低い延伸張力で分子鎖の塑性変形
や分子間またはミクロフィブリル間のすべりを容易にさ
せ、かつ伸長分子鎖による結晶化を促進させる必要があ
り、一般に温度を高くする手法が採られる。しかし、ポ
リエチレンの場合には１５５°Ｃ以上に温度を上げるこ
とは繊維の溶融が起こり易く、その結果、延伸時の導糸
が難しく、また導糸ができても溶融により延伸倍率の低
下があり望ましくなかった。実際、重量平均分子量が８
０万以上のポリエチレン繊維を２０倍以上に延伸する場
合、Ｐｏ１７ｍｅｒ　Ｂｕｌｌｅｔｉｎ　、第１巻、第
８７１〜８７６頁（１９７９）の報告や特開昭５８−５
２２８号公報に見られる如く延伸フィード速度は１０等
−以下と非常に遅く、高速で高倍率に延伸することはで
きなかった。また、高温で長時間延伸することは、分子
鎖の熱分解をひき起こして高強力繊維を得難い問題があ
る。Therefore, in order to increase the stretching ratio at high speed with the aim of improving operability, it is necessary to use a low stretching tension to facilitate plastic deformation of molecular chains and sliding between molecules or microfibrils, and to prevent crystallization due to stretched molecular chains. It is necessary to accelerate the process, and a method of increasing the temperature is generally adopted. However, in the case of polyethylene, raising the temperature above 155°C tends to cause the fibers to melt, making it difficult to guide the fibers during drawing, and even if the fibers can be guided, the draw ratio may decrease due to melting. It was undesirable. In fact, the weight average molecular weight is 8
When stretching polyethylene fibers of 10,000 or more by 20 times or more, the report of Po17mer Bulletin, Vol. 1, pp. 871-876 (1979) and JP-A-58-5
As seen in Japanese Patent No. 228, the stretching feed rate was very slow at 10 or less, and it was not possible to stretch at high speed and at a high magnification. Further, stretching at high temperatures for a long time causes thermal decomposition of the molecular chains, making it difficult to obtain high-strength fibers.

かかる背景によシ、本発明者らは超高分子量ポリエチレ
ン繊維を操業性良く製造するために高速で２０倍以上に
延伸する方法について鋭意検討した結果、延伸倍率、フ
ィード速度および温度に対して延伸ヒーターの最適な長
さを設定することにより、延伸速度を大きくしても十分
に分子鎖の塑性変形が起こって高倍率延伸ができ、かつ
分子鎖の熱分解が抑えられる結果、高強力繊維が得られ
易いことを見出した。Against this background, the present inventors have conducted intensive studies on a method of drawing ultra-high molecular weight polyethylene fibers at a high speed of 20 times or more in order to produce them with good operability. By setting the optimal length of the heater, plastic deformation of the molecular chains occurs even when the drawing speed is increased, allowing high-strength drawing, and thermal decomposition of the molecular chains is suppressed, resulting in high-strength fibers. I found that it is easy to obtain.

すなわち、本発明は重量平均分子量が８０万以上のポリ
エチレンを４〜１２重量％含む溶液から得られたところ
の、溶剤含有率がポリエチレンに対し１００重量％以下
の紡糸原糸を、１対のローラー間にヒーターを有する方
式で１段延伸する際に、下記（１）式が成立するように
ヒーター長を設定し、２０倍以上に延伸することを特徴
とする高強力ポリエチレン繊維の延伸方法に関するもの
である。That is, in the present invention, a spun fiber having a solvent content of 100% by weight or less based on polyethylene, which is obtained from a solution containing 4 to 12% by weight of polyethylene having a weight average molecular weight of 800,000 or more, is spun with a pair of rollers. A method for drawing high-strength polyethylene fibers, which is characterized by setting the length of the heater so that the following formula (1) is satisfied during one-step drawing using a method with a heater between the fibers, and drawing the fiber by 20 times or more. It is.

５０ Ｌ　＝　（ＨＤ−１）ｘδｒｘ　−＋　４−＝　（１）
ただし、ＨＤ≧２０．０．１≦■１≦１０．１１Ｇ≦Ｔ
≦１５０以下に本発明の内容を詳細に説明する。50 L = (HD-1)xδrx −+ 4−= (1)
However, HD≧20.0.1≦■1≦10.11G≦T
≦150 Below, the content of the present invention will be explained in detail.

本発明にいうポリエチレンは重量平均分子量が８０万以
上のものであり、２０モル多以下の割合で他のポリマー
を共重合したものや染色、制電、耐熱、耐光、難燃々ど
を向上させる目的で２０モルチ以下の改質剤を共重合し
たもの、壕だけ光沢、着色、高比重、導電、磁性、補強
々どを目的としたフィラーを２０重量係以下添加したも
の、あるいはこれらを２種以上混合したものを意味する
。The polyethylene referred to in the present invention has a weight average molecular weight of 800,000 or more, and is copolymerized with other polymers in a proportion of 20 moles or less, and has improved dyeing, antistatic, heat resistance, light resistance, flame retardancy, etc. Copolymerized with 20 mole or less of a modifier for the purpose, or added with less than 20 mass of filler for the purpose of gloss, coloring, high specific gravity, conductivity, magnetism, reinforcement, etc., or two types of these. It means a mixture of the above.

ここで、重量平均分子量が８０万未満では２０倍以上の
延伸は難しく、たとえば強度２０ｇ／ｄ以上の如き高強
力繊維を得ることは困難である。Here, if the weight average molecular weight is less than 800,000, it is difficult to stretch the fiber by a factor of 20 or more, and it is difficult to obtain a high-strength fiber having a strength of 20 g/d or more, for example.

ポリエチレンを溶解する溶剤は、冷却固化の点で好オし
くけ７０°Ｃ以上の相分離温度を有するものであり、該
溶剤の沸点は原液調製時や紡糸時の溶剤蒸発と乾燥の効
率化からして２５０°Ｃ以下、好オしくは１５０〜２０
０°Ｃであるが、溶剤を他の抽出剤で繊維から除去する
場合はこの限りでけ々い。該溶剤としては、たとえばノ
ナン、デカン、ウンデカン、ドデカン、デカリン、キシ
レン、ナフタリン、パラフィンなどの脂肪族まだは脂環
式炭化水素あるいは脂肪族炭化水素が主成分の石油系ソ
ルベントあるいはジクロルベンゼンなどのノ・ロゲン化
炭化水素あるいはこれら２種以上の混合溶剤などがある
が、本発明はこれらに限定されるものではない。Solvents that dissolve polyethylene are preferred in terms of cooling and solidification, and have a phase separation temperature of 70°C or higher. and 250°C or less, preferably 150-20°C
Although the temperature is 0°C, this limit is sufficient if the solvent is removed from the fibers using other extractants. Examples of the solvent include aliphatic or alicyclic hydrocarbons such as nonane, decane, undecane, dodecane, decalin, xylene, naphthalene, and paraffin, petroleum-based solvents mainly composed of aliphatic hydrocarbons, and dichlorobenzene. Examples include halogenated hydrocarbons and mixed solvents of two or more of these, but the present invention is not limited thereto.

超高分子量ポリエチレンを溶剤に溶解するときの濃度は
４〜１２重量％であり、４重量％未満では曳糸性がなく
なり紡糸が困難であり、かつ紡糸原糸の膠着性や経時変
化さらには操業効率が低下するので好ましくない。また
、ポリエチレン濃度が１２重量％を越えると粘度が非常
に高く均一な溶解が難しく、また濃度増加や溶解のため
の激しい攪拌により分子鎖のからみが多くなり、超延伸
ができなくなる問題を生ずる。本発明においては、かか
るポリエチレン溶液を通常のギヤポンプと紡糸ノズルを
用いて繊維状に吐出させ、同時に冷却固化させて繊維化
するが、この場合、延伸倍率の増大を計るうえで紡糸ド
ラフトは３０倍以下が好ましい。When ultra-high molecular weight polyethylene is dissolved in a solvent, the concentration is 4 to 12% by weight, and if it is less than 4% by weight, spinnability will be lost and spinning will be difficult, as well as the stickiness of the spun yarn, changes over time, and problems during operation. This is not preferable because it reduces efficiency. Furthermore, if the polyethylene concentration exceeds 12% by weight, the viscosity is extremely high and uniform dissolution is difficult, and increasing the concentration or vigorous stirring for dissolution increases the entanglement of molecular chains, causing the problem that super-stretching becomes impossible. In the present invention, the polyethylene solution is discharged in the form of fibers using an ordinary gear pump and spinning nozzle, and simultaneously cooled and solidified to form fibers. In this case, in order to increase the drawing ratio, the spinning draft is 30 times. The following are preferred.

延伸直前の紡糸原糸は溶剤含有率がポリエチレンに対し
て１００重量％以下、好ましくは２０重量％以下であり
、１００重量％を越えると延伸時に溶融したり溶剤の蒸
発潜熱による繊維の温度低下や温度斑を生じて延伸倍率
の低下を招くばかりか溶剤の飛散によるヒーター汚れや
環境汚染さらには溶剤回収の損失増加などの問題を生じ
好ましくない。ここで、溶剤含有率を１００重量％以下
にするためには紡糸原糸を乾燥または溶剤抽出処理する
必要があるが、紡糸原糸の膠着性や経時変化さらにはボ
ビンで捲取った場合の捲形状やボビンの内層と外層にお
ける延伸性の差などの点で捲取る前に連続的に溶剤を乾
燥オたは抽出する方法が好ましい。The solvent content of the spun yarn immediately before drawing is 100% by weight or less, preferably 20% by weight or less based on the polyethylene; if it exceeds 100% by weight, it may melt during drawing or the temperature of the fiber may drop due to the latent heat of vaporization of the solvent. This is undesirable because it not only causes temperature unevenness and lowers the stretching ratio, but also causes problems such as heater stains and environmental pollution due to solvent scattering, as well as increased losses in solvent recovery. Here, in order to reduce the solvent content to 100% by weight or less, it is necessary to dry or extract the spun yarn with a solvent. In view of the shape and the difference in stretchability between the inner and outer layers of the bobbin, a method of continuously drying or extracting the solvent before winding is preferred.

ついで、本発明において得られた紡糸原糸をローラーと
ヒーターを有する延伸装置で１段で延伸するが、この場
合、下記（１）式が成立するようにヒーター長を設定し
なければならない。Next, the spun yarn obtained in the present invention is drawn in one stage using a drawing device having a roller and a heater, but in this case, the length of the heater must be set so that the following formula (1) is satisfied.

ただし、ＨＤ≧２０．０１≦ｖ１≦１０．１１０≦Ｔ≦
１４５ここで、ヒーター長が（１）式からめた値より旬
かい場合は、分子鎖の十分な塑性変形（折シたたみ分子
鎖の引き伸ばし）が起こらないうちに伸長分子鎖の不完
全結晶が破壊されるために延伸張力が高く、２０倍以上
の延伸では繊維が切断して高強力繊維が得られない。一
方、ヒーター長が（１）式の値より長い場合は、延伸倍
率は高くなるが、逆に分子鎖の熱分解が起こり高強力繊
維が得難く、かつ操業性低下と々って好ましくない。こ
れに対して、ヒーター長が（１）式の値を満足している
場合は、分子鎖の十分な塑性変形（折りたたみ鎖の引き
伸ばし）が成され、また延伸時に生成した伸長分子鎖の
結晶化促進（強大で完全な結晶）によって主として折り
たたみ結晶の引き伸ばしが起こるために低延伸張力で高
倍率に延伸が可能であり、ひいては高速でも高倍率延伸
ができ、高強力で高モジュラスの繊維が得られる。本発
明でいう高強力、高モジュラス繊維とは、引張強度２０
ｇ／ｄ以上、好ましくは２５〜４０ｇ／ｄであり、引張
弾性率４００　’／ｄ、好ましくは７００〜１，５００
　’／、３を有する繊維を意味し、超高分子量ポリエチ
レンの場合、２０倍以上、好ましくは２５〜４０倍の延
伸が必要である。However, HD≧20.01≦v1≦10.110≦T≦
145 Here, if the heater length is shorter than the value calculated from equation (1), the incomplete crystal of the elongated molecular chain will break before sufficient plastic deformation of the molecular chain (stretching of the folded molecular chain) occurs. Because of this, the stretching tension is high, and if the stretching is 20 times or more, the fibers will break and high-strength fibers cannot be obtained. On the other hand, if the heater length is longer than the value of formula (1), the stretching ratio will increase, but conversely, the molecular chains will be thermally decomposed, making it difficult to obtain high-strength fibers, and the operability will deteriorate, which is undesirable. On the other hand, when the heater length satisfies the value of formula (1), sufficient plastic deformation of the molecular chains (stretching of folded chains) is achieved, and crystallization of the extended molecular chains generated during stretching occurs. Because stretching of folded crystals mainly occurs due to acceleration (strong and perfect crystals), it is possible to draw at a high magnification with low stretching tension, and even at high speeds, it is possible to obtain fibers with high strength and high modulus. . In the present invention, the high strength and high modulus fibers refer to tensile strength of 20
g/d or more, preferably 25 to 40 g/d, and tensile modulus of 400'/d, preferably 700 to 1,500
In the case of ultra-high molecular weight polyethylene, it is necessary to stretch the fiber by 20 times or more, preferably 25 to 40 times.

本発明における延伸のフィード速度は０．１〜１０シー
、好ましくは０．５〜５−一であり、０．１５講未満で
は生産性は極端に低下し、フィード速度が１０−一を越
えると、（１）式でめたヒーター長より長くしても２０
倍延伸が難しく、また６ａｍ以上のヒーターが必要で操
作性および操業性の点で問題がある。The feed rate for stretching in the present invention is from 0.1 to 10 seas, preferably from 0.5 to 5 seams; if the feed rate is less than 0.15 seams, the productivity will be extremely reduced, and if the feed speed exceeds 10 seams, the productivity will be extremely reduced. , even if it is longer than the heater length determined by equation (1), it is 20
Double stretching is difficult, and a heater of 6 am or more is required, which poses problems in terms of operability and operability.

本発明で用いられるヒーターは接触型、非接触型のどち
らでもよいが、繊維の融断、フィブリル化、毛羽立ちな
どの点で非接触型中空ヒーターが好ましい。また、加熱
方式は電気または熱媒による熱板加熱でも、熱風による
加熱でも支障ないが、できる限り温度斑と糸揺れの少な
い方式が好ましい。ヒータ一温度は平均が１１０°Ｃか
ら１５０°Ｃまでであることが必要であるが、ヒーター
内の温度斑で１５５°Ｃ以上になる部分がある場合には
繊維の融断が起こり易く好ましくない。なお、ヒーター
を多数釜べて使用する場合、各ヒーターの温度が平均１
１０°Ｃ〜１５０℃の間であればヒーター間で温度差を
与えてもなんら支障ない。ヒーター間で温度差がある場
合、（１）式の温度Ｔはヒーター間の平均温度を意味す
る。ここで、ヒーターの平均温度が１１０°Ｃ未満の場
合、（１）式からめたヒーター長では繊維の加熱が不十
分で２０倍以上延伸することは難しく、また延伸倍率を
大きくするためにはヒーターを著しく長くする必要があ
り、好ましくない。また、平均温度が１５５°Ｃ以上で
は繊維の融断と熱分解が起こり易く、本発明ではヒータ
一温度は１１０〜１５０°Ｃ１好ましくは１５０〜１４
５°Ｃであシ、非接触型中空ヒーターを用いる場合は糸
条走行雰囲気の平均温度が１２０〜１５０°Ｃであるこ
とが好ましい。なお、ヒーターが１０ｍ以上のように長
い場合には操作性の点で中間にガイドを設けてヒーター
を２つ以上に分けることは問題ない。The heater used in the present invention may be either a contact type or a non-contact type, but a non-contact type hollow heater is preferable in terms of fusing, fibrillation, fluffing, etc. of fibers. Further, the heating method may be hot plate heating using electricity or a heating medium, or heating using hot air, but a method that causes as little temperature unevenness and yarn shaking as possible is preferable. The average temperature of the heater needs to be between 110°C and 150°C, but if there are uneven temperatures within the heater that exceed 155°C, this is not preferable as fibers are likely to melt and break. . Note that when using multiple heaters, the average temperature of each heater is 1.
If the temperature is between 10°C and 150°C, there will be no problem even if a temperature difference is given between the heaters. When there is a temperature difference between the heaters, the temperature T in equation (1) means the average temperature between the heaters. Here, if the average temperature of the heater is less than 110°C, the heater length calculated from equation (1) will not heat the fibers enough and it will be difficult to stretch them 20 times or more. , which is not desirable. Furthermore, if the average temperature is 155°C or higher, fiber melting and thermal decomposition are likely to occur, so in the present invention, the heater temperature is 110 to 150°C, preferably 150 to
When using a non-contact type hollow heater, it is preferable that the average temperature of the yarn running atmosphere is 120 to 150°C. Note that when the heater is long, such as 10 m or more, there is no problem in dividing the heater into two or more parts by providing a guide in the middle from the viewpoint of operability.

本発明によって延伸性、操作性および操業性の点で最適
なヒーター長が設定され、延伸速度が大きい場合でも高
倍率延伸ができ、高強力で高モジュラスのポリエチレン
繊維を操業性よく製造することが可能となった。According to the present invention, the optimum heater length is set in terms of drawability, operability, and operability, and even when the drawing speed is high, it is possible to draw at a high magnification, and it is possible to produce polyethylene fibers with high strength and high modulus with good operability. It has become possible.

以下に本発明を実施例により具体的に説明する。The present invention will be specifically explained below using examples.

実施例１ 重量平均分子量２００万のポリエチレン粉末を濃度６重
量４になるようにデカリンに添加して溶解したのち該溶
液をギヤポンプにて紡糸口金から吐出させ紡糸トラフ）
１１．０倍で冷却固化により繊維化した。ついで、連続
的に熱風乾燥機内で乾燥し、ポリエチレンに対するデカ
リン含有率を１５重量％にしてボビンに捲取った。得ら
れた紡糸原糸をフィードローラー速度１５い延伸倍率２
８倍、非接触型中空ヒーターの糸条走行雰囲気の平均温
度１４０°Ｃ，ヒーター長１５ｍ＋１５ｍ（合計３０ｍ
）にて１段延伸を行ない２８１シーの速度で捲取った。Example 1 Polyethylene powder with a weight average molecular weight of 2 million was added to decalin at a concentration of 6 weight 4 and dissolved, and then the solution was discharged from a spinneret using a gear pump to form a spinning trough.
It was made into fibers by cooling and solidifying at a magnification of 11.0 times. Then, it was continuously dried in a hot-air dryer, and the decalin content relative to polyethylene was adjusted to 15% by weight, and the material was wound onto a bobbin. The obtained spun yarn was stretched at a feed roller speed of 15 and a stretching ratio of 2.
8 times, average temperature of yarn running atmosphere of non-contact hollow heater 140°C, heater length 15m + 15m (total 30m
) and rolled up at a speed of 281 sheets.

こうして得られた延伸糸の引張強伸度はそれぞれ２９．
２７，１　、　ｓ、１％、モジュラスは８７６ｇ／ｄで
あり、従来にない高強力、高モジュラスなポリエチレン
繊維であった。また延伸糸は２１０ｄ／３６ｆであり、
５時間ずつ１０ドフイング延伸を行なったが、断糸はな
く、単糸切れが１回、フィブリル状の毛羽が２個見つか
っただけで良好であった。The tensile strength and elongation of the drawn yarn thus obtained was 29.
27,1, s, 1%, and the modulus was 876 g/d, making it a polyethylene fiber with unprecedented high strength and high modulus. In addition, the drawn yarn is 210d/36f,
Although 10 doffing stretches were carried out for 5 hours each, there was no yarn breakage, only one single yarn breakage and two fibril-like fluffs were found.

さらに１０本の延伸糸について１ｍ間隔で５０〃１間の
繊度と強度の変動状況を測定したが、いずれも±５チ以
内の変動であり、ドフイング初めと終りの延伸糸でとく
に有意差は見られなかった。得られた延伸糸は着色もな
く、分子鎖は分解していないように思われたが、念のた
めに絶乾後の紡糸原糸および延伸糸について１３５℃の
デカリンに溶解した溶液の粘度を測定したところ、原糸
と延伸糸はほとんど同じであり、延伸時の熱分解が起こ
っていないことが判明した。Furthermore, we measured the fluctuations in fineness and strength of 10 drawn yarns at 1 m intervals, and the fluctuations were within ±5 inches, and no significant difference was observed between the drawn yarns at the beginning and end of doffing. I couldn't. The obtained drawn yarn was not colored and the molecular chains did not seem to be decomposed, but just to be sure, we measured the viscosity of a solution of the spun yarn and drawn yarn after they were completely dried in decalin at 135°C. As a result of measurement, it was found that the raw yarn and the drawn yarn were almost the same, and no thermal decomposition occurred during the drawing.

実施例２ 重量平均分子量１５０万のポリエチレン粉末を濃度１０
重量％になるように石油系ンルベント（沸点１８５〜２
１０℃）に添加して溶解したのち、吐出量２４　ｃｃ／
、Ｒ１紡糸速度２０咄、紡糸ドラ７）１７．５倍にて紡
糸し、ついで８０°Ｃの熱風乾燥によシ溶剤含有率を５
８８重量％して紡糸原糸を捲取った。該紡糸原糸をフィ
ード速度４−５　”／ｗｉｎ、延伸倍率２３倍で１５０
°Ｃと１４０°Ｃの熱風循環式スリットヒーターの中を
通し、１段でローラー延伸を行なった。このときのスリ
ットヒーターの長さは１５０℃が２５ｍ、１４０℃が２
５ｍ（合計５０ｍ）であり、ヒーターの中間にはガイド
を設けて操作性を良くした。延伸糸は１００ｄ／２４ｆ
で５時間延伸したが、毛羽断糸はなく、捲取ローラー直
前の延伸張力は２９０〜５０５ｇと大きな変動はみられ
ず、安定した延伸状態であった。Example 2 Polyethylene powder with a weight average molecular weight of 1.5 million was prepared at a concentration of 10
Petroleum-based lubricants (boiling point 185-2
After adding and dissolving at 10℃), the discharge amount was 24 cc/
, R1 spinning speed 20 k, spinning drum 7) Spun at 17.5 times, and then dried with hot air at 80°C to reduce the solvent content to 5
The spinning yarn was wound up with a concentration of 88% by weight. The spun yarn was fed at a feed rate of 4-5''/win and a stretching ratio of 23 times to 150 mm.
The film was passed through a hot air circulation type slit heater at temperatures of 140°C and 140°C, and roller stretching was performed in one stage. The length of the slit heater at this time is 25 m at 150°C and 2 m at 140°C.
5m (total 50m), and a guide was provided in the middle of the heater to improve operability. The drawn yarn is 100d/24f
Although the film was stretched for 5 hours, there was no fluff breakage, and the stretching tension immediately before the winding roller was 290 to 505 g, with no major fluctuations, indicating a stable stretching state.

得られた延伸糸の強度は２３．　ａ　’／ｄ、モジュラ
スは６７５ｇ／ｄであり、本発明により、高速で高倍率
延伸が可能となり、操業性良く高強力、高モジュラス繊
維を得ることができるようになった。The strength of the drawn yarn obtained was 23. a'/d and modulus were 675 g/d, and the present invention made it possible to draw at high speed and at a high magnification, making it possible to obtain high strength and high modulus fibers with good operability.

実施例５ 重量平均分子量３５０万のポリエチレンにグリーンの顔
料を１重量％添加し、ポリエチレン濃度が５重量％にな
るように石油系ソルベント（沸点１６５〜１９４°Ｃ）
で溶解して紡糸原液を作った。Example 5 1% by weight of green pigment was added to polyethylene with a weight average molecular weight of 3.5 million, and petroleum-based solvent (boiling point 165-194°C) was added so that the polyethylene concentration was 5% by weight.
to prepare a spinning stock solution.

得られた原液を用いて紡糸ドラフト５．６倍で紡糸し、
ついで９０°Ｃの熱風乾燥により溶剤含有率を２．１重
量％にして捲取った。ついで、該紡糸原糸をフィード速
度ｏ、ｓ”／ｍ、捲取速度１７−−、延伸倍率３４倍、
非接触型中空ヒーターの糸条走行雰囲気の平均温度１４
５°Ｃ、ヒーター長２５ｍにて１段延伸を行なった。Using the obtained stock solution, spinning was carried out at a spinning draft of 5.6 times,
The film was then dried with hot air at 90°C to a solvent content of 2.1% by weight and rolled up. Then, the spun yarn was fed at a feed rate of o, s''/m, a winding speed of 17--, a drawing ratio of 34 times,
Average temperature of yarn running atmosphere of non-contact hollow heater 14
One-stage stretching was performed at 5°C and a heater length of 25 m.

延伸糸の引張強伸度はそれぞれ５２６ｇ／ｄ、４．８チ
、モジュラスは９５０　ｇ／ｄであり、従来品に見られ
ない高強力、高モジュラス繊維が得られた。また、原糸
を１０本合糸して２時間ずつ５ドフイング延伸したが、
断糸や単糸切れはなく、フィブリル状の表面毛羽が３個
あっただけであった。The tensile strength and elongation of the drawn yarn were 526 g/d and 4.8 g/d, respectively, and the modulus was 950 g/d, resulting in a fiber with high strength and high modulus not found in conventional products. In addition, 10 raw yarns were combined and stretched for 5 doffings for 2 hours each.
There was no yarn breakage or single yarn breakage, and there were only three fibril-like surface fluffs.

そして、延伸糸の１ｍ間隔で２０〃１間を測定した繊度
変動率も２．４チと低く、原着糸にしては均一な延伸が
なされていることが判明した。Furthermore, the fineness variation rate measured at 1 m intervals of 20 cm of the drawn yarn was as low as 2.4 inches, indicating that uniform drawing was achieved for a spun-dyed yarn.

比較例１〜３ 比較例１として、実施例１でデカリン含有率を１５０重
量％にした紡糸原糸を用いて延伸したが、繊維の溶融が
起こり易いためか延伸倍率は１９．５倍と低く、延伸糸
の強度は１８．０ｇ／ｄと低い値を示した。Comparative Examples 1 to 3 As Comparative Example 1, the spun yarn with a decalin content of 150% by weight in Example 1 was used for stretching, but the stretching ratio was as low as 19.5 times, probably because the fibers tend to melt. The strength of the drawn yarn was as low as 18.0 g/d.

比較例２として、実施例１でヒーター長を１５ｍにした
が、延伸張力は高く、延伸倍率が１６倍に低下し、高強
力繊維は得られなかった。As Comparative Example 2, the heater length was set to 15 m in Example 1, but the stretching tension was high, the stretching ratio was reduced to 16 times, and high strength fibers were not obtained.

比較例６として、実施例６でヒーター長を４０ｍにして
５４倍延伸を行なったが、得られた延伸糸は着色が少し
見られ、強度は２７．１Ｖ／ｄ、モジュラスは７４　ａ
　ｇ／ａに低下した。原糸と延伸糸について、デカリン
を溶剤として濃度０．０５％で１！＋５°Ｃの溶液粘度
を測定したところ、延伸糸は原糸に対し約２０係の粘度
低下がみられ、一部、分子鎖の熱分解が起こっているこ
とが判明した。As Comparative Example 6, the heater length of Example 6 was changed to 40 m and the yarn was drawn 54 times, but the resulting drawn yarn showed some coloring, had a strength of 27.1 V/d, and a modulus of 74 a.
g/a. 1 for raw yarn and drawn yarn at a concentration of 0.05% using decalin as a solvent! When the solution viscosity at +5°C was measured, it was found that the viscosity of the drawn yarn was about 20 times lower than that of the original yarn, indicating that some molecular chains had thermally decomposed.

特許出願人　株式会社り　ラ　し 代理人　弁理士本多　堅Patent applicant Rishi Co., Ltd. Agent: Patent Attorney Ken Honda

Claims (1)

【特許請求の範囲】 １ン重量平均分子量が８０万以上のポリエチレンを４〜
１２重量％含む溶液から得られたところの、溶剤含有率
がポリエチレンに対して１００重量％以下の紡糸原糸を
、１対のローラー間にヒーターを有する方式で１段延伸
するに際し、下記（１）式が成立するようにヒーター長
を設定し、２０倍以上に延伸することを特徴とする高強
力ポリエチレン繊維の延伸方法。 ただし、Ｌはヒーター長＜ｍ）、ＨＤは延伸倍率（倍）
、ｖｌはフィード速度（ｍ／、い、Ｔはヒーター平均温
度（°Ｃ）であって、ＨＤ≧２０．０．１≦Ｖ１≦１０
．１１０≦Ｔ≦１５０である。 ２）第１項において、溶剤含有率が２０重ｉ％以下であ
る紡糸原糸を延伸することを特徴とする高強力ポリエチ
レン繊維＆維の延伸方法。 ６）第１項および第２項のいずれかにおいて、延伸フィ
ード速度が０．５〜５　ｎＶ、い延伸倍率が２５〜４０
倍であることを特徴とする高強力ポリエチレン繊維の延
伸方法。 ４）第１項ないし第６項のいずれかにおいて、ヒーター
として非接触型中空ヒーターを用い、糸条走行雰囲気の
平均温度が１２０〜１５０°Ｃであることを特徴とする
高強力ポリエチレン繊維の延伸方法。[Claims] Polyethylene having a weight average molecular weight of 800,000 or more
When a spun yarn obtained from a solution containing 12% by weight and having a solvent content of 100% by weight or less based on polyethylene is drawn in one stage using a method having a heater between a pair of rollers, the following (1) ) A method for stretching high-strength polyethylene fibers, the length of the heater being set so that the formula holds true, and stretching 20 times or more. However, L is heater length < m), HD is stretching ratio (times)
, vl is the feed rate (m/, T is the average temperature of the heater (°C), HD≧20.0.1≦V1≦10
．． 110≦T≦150. 2) The method for drawing high-strength polyethylene fibers and fibers according to item 1, which comprises drawing a spun yarn having a solvent content of 20% by weight or less. 6) In either of the first and second terms, the stretching feed rate is 0.5 to 5 nV, and the stretching ratio is 25 to 40.
A method for drawing high-strength polyethylene fibers, which is characterized by double the amount. 4) In any one of Items 1 to 6, the drawing of high-strength polyethylene fiber is characterized in that a non-contact hollow heater is used as the heater and the average temperature of the yarn running atmosphere is 120 to 150°C. Method.