JPH0665858A - Production of surface-modified carbon fiber - Google Patents
Production of surface-modified carbon fiberInfo
- Publication number
- JPH0665858A JPH0665858A JP4221327A JP22132792A JPH0665858A JP H0665858 A JPH0665858 A JP H0665858A JP 4221327 A JP4221327 A JP 4221327A JP 22132792 A JP22132792 A JP 22132792A JP H0665858 A JPH0665858 A JP H0665858A
- Authority
- JP
- Japan
- Prior art keywords
- carbon fiber
- pitch
- electrolytic oxidation
- oxidation treatment
- producing
- 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
- Inorganic Fibers (AREA)
- Chemical Or Physical Treatment Of Fibers (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は表面改質炭素繊維の製造
方法の改良に関するものである。さらに詳しくは、本発
明は特にＣＦＲＰ（炭素繊維強化プラスチックス）用と
して好適な、樹脂との接着強度を改善させた高強度，高
弾性を有する表面改質ピッチ系炭素繊維を効率よく製造
する方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved method for producing surface-modified carbon fibers. More specifically, the present invention is a method for efficiently producing a surface-modified pitch-based carbon fiber having high strength and elasticity, which is particularly suitable for CFRP (carbon fiber reinforced plastics) and has improved adhesive strength with a resin. It is about.
【０００２】[0002]
【従来の技術】近年、炭素繊維は高強度及び高弾性率を
有し、かつ軽量であるなど、優れた特徴を有することか
ら、例えば航空機部品，自動車部品，スポーツ用具など
の種々の分野における素材や樹脂補強材などとして著し
く需要が伸びている。この炭素繊維はポリアクリロニト
リル系（ＰＡＮ系）炭素繊維とピッチ系炭素繊維とに大
別することができ、前者のＰＡＮ系炭素繊維は、ポリア
クリロニトリルを原料とする高性能（ＨＰ）グレードの
ものであって、通常高強度及び中程度の弾性率を有して
いる。しかしながら、このＰＡＮ系炭素繊維において
は、アクリロニトリル繊維は原料として高価である上
に、炭素繊維収率が４５％以下と極めて悪く、かつ処理
工程が煩雑であって、製造コストが高くつくのを免れな
いという欠点がある。一方、ピッチ系炭素繊維は石油系
ピッチ又はコールタール系ピッチなどを原料とするもの
であって、原料ピッチが安価で、かつ豊富に入手できる
上、炭素繊維収率が高いというメリットがあるものの、
一般的に上記ＰＡＮ系炭素繊維に比べて性能が劣るとい
う欠点を有している。2. Description of the Related Art In recent years, carbon fibers have excellent characteristics such as high strength and high elastic modulus and light weight. Therefore, carbon fibers are used as materials in various fields such as aircraft parts, automobile parts and sports equipment. Demand is growing remarkably as a resin reinforcement material. This carbon fiber can be roughly classified into polyacrylonitrile-based (PAN-based) carbon fiber and pitch-based carbon fiber. The former PAN-based carbon fiber is a high-performance (HP) grade that is made from polyacrylonitrile. Therefore, it usually has a high strength and a medium elastic modulus. However, in this PAN-based carbon fiber, acrylonitrile fiber is expensive as a raw material, the yield of carbon fiber is extremely poor at 45% or less, and the treatment process is complicated, which inevitably leads to high manufacturing cost. It has the drawback of not being. On the other hand, the pitch-based carbon fiber is made from petroleum-based pitch or coal tar-based pitch as a raw material, and the raw material pitch is inexpensive and can be abundantly obtained, but there is an advantage that the carbon fiber yield is high,
Generally, it has a drawback that the performance is inferior to that of the above-mentioned PAN-based carbon fiber.
【０００３】したがって、このような欠点を改良するた
めに、種々研究がなされ、最近では光学的異方性相を含
むメソフェーズ（液晶）ピッチや、ネオメソフェーズピ
ッチ，プリメソフェーズピッチ，潜在的異方性ピッチな
どから強度及び弾性率の高い高性能（ＨＰ）炭素繊維を
得ることに成功している。なお、光学的等方性ピッチか
らは、通常強度及び弾性率の低い汎用（ＧＰ）炭素繊維
しか得られない。ところで、高強度，高弾性炭素繊維を
強化材とする炭素繊維強化プラスチックスは、高性能複
合材料として、医療用機器，宇宙航空飛行物体，陸上輸
送用機器，スポーツ用具などに広く用いられている。こ
の炭素繊維強化プラスチックスのような複合材料におい
ては、炭素繊維の特性、特にその力学的性質を複合材料
に反映させるには、該複合材料のマトリックスと炭素繊
維との接着性や一体化が重要である。炭素繊維は予めな
んらかの表面処理を行わないと、マトリックスに対する
接着性が充分でなく、マトリックスからの「すぬけ」が
生じやすく、補強効果を充分に発揮することができな
い。Therefore, various studies have been carried out to improve such defects, and recently, mesophase (liquid crystal) pitch containing an optically anisotropic phase, neomesophase pitch, premesophase pitch, and latent anisotropy. We have succeeded in obtaining high-performance (HP) carbon fibers with high strength and elastic modulus from pitch and the like. It should be noted that from the optically isotropic pitch, only general-purpose (GP) carbon fibers having low strength and low elastic modulus can be obtained. By the way, carbon fiber reinforced plastics having high strength and high elasticity carbon fiber as a reinforcing material are widely used as a high performance composite material for medical devices, aerospace flying objects, ground transportation devices, sports equipment and the like. . In a composite material such as this carbon fiber reinforced plastics, in order to reflect the characteristics of the carbon fiber, particularly its mechanical properties, in the composite material, the adhesiveness and integration of the matrix of the composite material and the carbon fiber are important. Is. If the carbon fiber is not subjected to any surface treatment in advance, the carbon fiber does not have sufficient adhesiveness to the matrix, "snack" from the matrix is likely to occur, and the reinforcing effect cannot be sufficiently exhibited.
【０００４】この現象は、特に複合材料中の補強繊維の
方向に直交する方向の強度に対して顕著に影響し、炭素
繊維とマトリックスとの接着性の評価は、層間剪断強度
を代表特性として実施されることが多い。炭素繊維の表
面処理法としては、酸化剤による液相酸化法，ヒートク
リーニング法，気相酸化法，ウイスカライジング法，電
解酸化法などが知られており、これらの中で液相酸化法
や電解酸化法、特に電解酸化法はその操業性に優れてい
ることから広く採用されている。しかしながら、一般に
光学的異方性相を含むピッチを原料とした高弾性のメソ
フェーズピッチ系炭素繊維においては、ポリアクリロニ
トリル系炭素繊維に比べて結晶構造が高配向であるた
め、表面不活性部が多く、前記のような酸化処理を行っ
ても、表面酸素濃度（Ｏ／Ｃ比）は極めて低く、充分に
表面改質されず、マトリックスとの接着強度が不充分で
あるという欠点を有している。また、高配向の結晶構造
を有しているため、樹脂との複合材料におけるＩＬＳＳ
（層間剪断強度）試験において、しばしば応力下での座
屈を生じてしまい、層間破壊のみにより、応力を分散さ
せることができないという問題もある。したがって、こ
れらのことから、ＩＬＳＳ値は低い値になってしまい、
高弾性炭素繊維を用いたＣＦＲＰの物性発現が制限され
るのを免れないという好ましくない事態を招来する。This phenomenon remarkably affects the strength in the direction orthogonal to the direction of the reinforcing fiber in the composite material, and the adhesion between the carbon fiber and the matrix is evaluated by using the interlaminar shear strength as a representative characteristic. It is often done. Known surface treatment methods for carbon fibers include liquid-phase oxidation with an oxidant, heat cleaning, gas-phase oxidation, whiskerizing, and electrolytic oxidation. Among these, liquid-phase oxidation and electrolytic oxidation are known. Oxidation methods, especially electrolytic oxidation methods, are widely used because of their excellent workability. However, generally, in the highly elastic mesophase pitch-based carbon fiber made from the pitch containing the optically anisotropic phase as a raw material, the crystal structure is highly oriented as compared with the polyacrylonitrile-based carbon fiber, and therefore the surface inactive portion is often present. The surface oxygen concentration (O / C ratio) is extremely low even if the above-mentioned oxidation treatment is performed, the surface is not sufficiently modified, and the adhesive strength with the matrix is insufficient. . In addition, since it has a highly oriented crystal structure, ILSS in a composite material with resin
In the (interlayer shear strength) test, there is also a problem that buckling often occurs under stress, and stress cannot be dispersed only by interlaminar failure. Therefore, from these things, the ILSS value becomes a low value,
This leads to an unfavorable situation in which the physical properties of CFRP using high elastic carbon fiber are limited.
【０００５】[0005]
【発明が解決しようとする課題】本発明は、このような
事情のもとで、特にＣＦＲＰ用として好適に用いられ
る、樹脂との接着強度が改善された高強度，高弾性を有
する表面改質ピッチ系炭素繊維を効率よく製造する方法
を提供することを目的としてなされたものである。Under these circumstances, the present invention is a surface modification having high strength and high elasticity, which is preferably used for CFRP and has improved adhesive strength with a resin. The purpose of the present invention is to provide a method for efficiently producing pitch-based carbon fibers.
【０００６】[0006]
【課題を解決するための手段】本発明者らは、前記目的
を達成するために鋭意研究を重ねた結果、ピッチ系炭素
繊維を電解酸化により表面処理したのち、その表面を化
学気相蒸着法（ＣＶＤ法）にて、非晶質炭素で被覆する
ことにより、その目的を達成しうることを見出した。本
発明はこのような知見に基づいてなされたものである。
すなわち本発明は、ピッチを紡糸して得られたピッチ繊
維を不融化したのち、不活性ガス雰囲気下で焼成してな
る炭素繊維を電気量５０クーロン／ｇ以上で電解酸化処
理し、次いで処理された炭素繊維の表面を炭化水素ガス
を原料とする化学気相蒸着法により非晶質炭素で被覆す
ることを特徴とする表面改質炭素繊維の製造方法を提供
するものである。Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the inventors of the present invention have found that pitch-based carbon fibers are surface-treated by electrolytic oxidation and then the surface thereof is subjected to chemical vapor deposition. It was found that the objective can be achieved by coating with amorphous carbon by (CVD method). The present invention has been made based on such findings.
That is, according to the present invention, pitch fibers obtained by spinning pitch are infusibilized, and then carbon fibers obtained by firing in an inert gas atmosphere are electrolytically oxidized at an electric quantity of 50 coulomb / g or more, and then treated. The present invention provides a method for producing a surface-modified carbon fiber, which comprises coating the surface of the carbon fiber with amorphous carbon by a chemical vapor deposition method using a hydrocarbon gas as a raw material.
【０００７】本発明の方法において用いられる紡糸用ピ
ッチは、石油系，石炭系のいずれであってもよく、ま
た、光学的等方性ピッチや光学的異方性相を含むメソフ
ェーズピッチ、あるいはネオメソフェーズピッチ，プリ
メソフェーズピッチ，潜在的異方性ピッチなどの中から
任意のものを選択して用いることができるが、高強度，
高弾性の炭素繊維を得るには、光学的等方性ピッチは好
ましくない。また、原料ピッチの種類については特に制
限はなく、例えば原油蒸留残渣油，流動接触分解（ＦＣ
Ｃ）重質油，ナフサ分解残渣油，エチレンボトム油など
の石油系ピッチ（重質油）、コールタール，石炭液化油
などの石炭系ピッチ（重質油）を、ろ過，蒸留，水添，
接触分解などの処理工程を経て調製されたものを用いる
ことができる。The spinning pitch used in the method of the present invention may be either petroleum-based or coal-based, and isotropic pitch, mesophase pitch containing an optically anisotropic phase, or neo-pitch. Any of mesophase pitch, premesophase pitch, latent anisotropic pitch, etc. can be selected and used, but high strength,
Optically isotropic pitches are not preferred for obtaining highly elastic carbon fibers. Also, there is no particular limitation on the type of raw material pitch, for example, crude oil distillation residual oil, fluid catalytic cracking (FC
C) Heavy oil, naphtha cracked residual oil, petroleum pitch (heavy oil) such as ethylene bottom oil, coal tar, coal liquefied oil (coal pitch) (heavy oil), filtration, distillation, hydrogenation,
What was prepared through the process steps, such as catalytic decomposition, can be used.
【０００８】本発明においては、まず、上記紡糸用ピッ
チを紡糸してピッチ繊維を作成する。紡糸方法について
は特に制限はなく、従来公知の溶融紡糸法を用いること
ができる。例えば該紡糸用ピッチを、その軟化点に応じ
た範囲の温度において溶融紡糸し、糸径５〜３０μｍ程
度のピッチ繊維を作成する。次いで、上記ピッチ繊維の
不融化処理を行うが、この不融化処理は酸素，酸素リッ
チガス，空気，ＮＯ2 などの雰囲気下、通常の条件で行
われる。次に、このようにして不融化処理された繊維に
炭化処理が施されるが、必要に応じ、窒素やアルゴンな
どの不活性ガス雰囲気下、軽度の予備炭化処理を行って
もよい。炭化又は黒鉛化処理は、窒素やアルゴンなどの
不活性ガス雰囲気下、通常の条件において行われる。本
発明において用いられる炭素繊維は、上記の所定の方法
にて、紡糸，不融化，炭化又は黒鉛化されたものであれ
ば特に制限されないが、後工程のＣＶＤ法により非晶質
炭素を析出させる温度以上、好ましくは１５００〜３０
００℃の範囲の温度において、上記の不融化処理繊維又
は必要に応じて予備炭化処理された繊維を、炭化又は黒
鉛化することによって得られた炭素繊維が好ましい。In the present invention, first, the above-mentioned spinning pitch is spun to produce pitch fibers. The spinning method is not particularly limited, and a conventionally known melt spinning method can be used. For example, the spinning pitch is melt-spun at a temperature in the range corresponding to the softening point to produce pitch fibers having a yarn diameter of about 5 to 30 μm. Next, the infusibilizing treatment of the pitch fibers is performed, and this infusibilizing treatment is performed under normal conditions in an atmosphere of oxygen, oxygen-rich gas, air, NO 2, or the like. Next, the fibers thus infusibilized are carbonized, but if necessary, a slight preliminary carbonization may be performed in an atmosphere of an inert gas such as nitrogen or argon. The carbonization or graphitization treatment is performed under normal conditions in an atmosphere of an inert gas such as nitrogen or argon. The carbon fiber used in the present invention is not particularly limited as long as it is spun, infusibilized, carbonized or graphitized by the above-mentioned predetermined method, but amorphous carbon is deposited by the CVD method in the subsequent step. Above temperature, preferably from 1500 to 30
A carbon fiber obtained by carbonizing or graphitizing the infusibilized fiber or the fiber preliminarily carbonized as necessary at a temperature in the range of 00 ° C. is preferable.
【０００９】本発明においては、上記炭素繊維に、電解
質として酸，中性塩，アルカリ塩などを用いて電解酸化
処理を施す。この電解酸化処理による炭素繊維の表面改
質の度合いは、電解液の種類や炭素繊維への通電量など
によって左右されるが、本発明においては、炭素繊維の
黒鉛層末端炭素原子に酸素原子を導入するのみでなく、
黒鉛層面の繊維軸方向の配向も乱す程度に酸化する必要
があるため、電解質として、好ましくは黒鉛層面を攻撃
しやすいＮＯ3 - やＳＯ4 2- をもつ硝酸や硫酸、あるい
はリン酸などの無機酸を用い、電気量５０クーロン／ｇ
以上で通電を行うことが必要である。また、炭素繊維を
陽極として電解酸化処理するのみでは、あまり繊維軸配
向を乱すことができないので、本発明においては、さら
に炭素繊維を陰極として電解酸化処理を行い、繊維軸配
向をより乱すのが望ましい。このようにして表面構造を
乱すことにより、後述のＣＶＤ法による非晶質炭素との
密着性を向上させることができる。In the present invention, the carbon fiber is subjected to electrolytic oxidation treatment using an acid, a neutral salt, an alkali salt or the like as an electrolyte. The degree of surface modification of the carbon fiber by this electrolytic oxidation treatment depends on the type of the electrolytic solution and the amount of electricity applied to the carbon fiber, but in the present invention, oxygen atoms are added to the carbon atoms at the graphite layer of the carbon fiber. In addition to introducing
Since it is necessary to oxidize the graphite layer surface to such an extent that the orientation in the fiber axis direction is also disturbed, it is preferable to use an inorganic material such as nitric acid, sulfuric acid, or phosphoric acid having NO 3 − or SO 4 2− as the electrolyte, which easily attacks the graphite layer surface Using acid, electricity 50 coulomb / g
It is necessary to energize as described above. Further, only by electrolytic oxidation treatment using carbon fiber as an anode, the fiber axis orientation cannot be disturbed so much, so in the present invention, electrolytic oxidation treatment is further performed using carbon fiber as the cathode to further disturb the fiber axis orientation. desirable. By disturbing the surface structure in this way, it is possible to improve the adhesion to the amorphous carbon by the CVD method described later.
【００１０】本発明においては、このようにして電解酸
化処理された炭素繊維表面を、ＣＶＤ法により非晶質炭
素で被覆するが、そのままＣＶＤを行うと、操作中に繊
維内部からガスが放出され、非晶質炭素の析出に悪影響
を及ぼすおそれがある。したがって電解酸化処理された
炭素繊維を酸素，酸素リッチガス，空気などの酸素含有
ガス雰囲気下、常圧又は減圧にて３５０℃以下の温度で
熱処理し、該繊維中のガス成分を取り除いてから、ＣＶ
Ｄを行うのが望ましい。この処理温度が３５０℃を超え
ると炭素繊維自体が表面酸化をうけるので好ましくな
い。In the present invention, the surface of the carbon fiber thus electrolytically oxidized is coated with amorphous carbon by the CVD method. However, if the CVD is performed as it is, gas is released from the inside of the fiber during the operation. However, it may adversely affect the precipitation of amorphous carbon. Therefore, the electrolytically oxidized carbon fiber is heat-treated at a temperature of 350 ° C. or less under atmospheric pressure or reduced pressure in an oxygen-containing gas atmosphere such as oxygen, oxygen-rich gas, or air to remove the gas component in the fiber, and then CV
It is desirable to perform D. If the treatment temperature exceeds 350 ° C., the carbon fiber itself undergoes surface oxidation, which is not preferable.
【００１１】本発明においては、このようにして処理さ
れた炭素繊維の表面に、炭化水素ガスを炭素源とし、か
つアルゴンや窒素などの不活性ガスをキャリアーガスと
して用い、好ましくは９００〜１４００℃の範囲の温度
でＣＶＤ法により非晶質炭素を析出させ、被覆層を設け
る。この被覆層の厚さについては特に制限はないが、通
常１００〜１００００Åの範囲にあるのが望ましい。こ
のＣＶＤ法において用いられる炭素源の炭化水素として
はメタン，エタン，プロパン，エチレン，プロピレン，
アセチレンなどが挙げられ、これらは一種用いてもよ
く、又二種以上を組み合わせて用いてもよい。このよう
にして、樹脂との接着性に優れ、かつ高強度，高弾性の
表面が非晶質炭素で被覆された表面改質炭素繊維が得ら
れる。この炭素繊維は、電解酸化処理などの表面処理を
施さなくても、樹脂との複合材料においては、層間剪断
強度が高く、しかもＩＬＳＳ試験における破壊モードは
座屈は生ぜず、層間に沿って応力を分散させることがで
きるが、場合によっては、電解質として中性塩やアルカ
リ塩を用い、２０Ｃ／ｇ以下の電気量による軽度の電解
酸化処理を施し、樹脂との密着性に関与する表面酸素濃
度（Ｏ／Ｃ比）を増加させて、接着強度をさらに向上さ
せることができる。In the present invention, a hydrocarbon gas is used as a carbon source and an inert gas such as argon or nitrogen is used as a carrier gas on the surface of the carbon fiber thus treated, and preferably 900 to 1400 ° C. Amorphous carbon is deposited by the CVD method at a temperature in the range of 1 to provide a coating layer. The thickness of this coating layer is not particularly limited, but it is usually desirable to be in the range of 100 to 10000Å. The carbon source hydrocarbons used in this CVD method include methane, ethane, propane, ethylene, propylene,
Examples thereof include acetylene and the like, and these may be used alone or in combination of two or more kinds. In this way, a surface-modified carbon fiber having excellent adhesiveness with a resin and having a high strength and high elasticity whose surface is coated with amorphous carbon can be obtained. This carbon fiber has a high interlaminar shear strength in a composite material with a resin without being subjected to a surface treatment such as electrolytic oxidation treatment, and further, the failure mode in the ILSS test does not cause buckling and stress along the interlaminar layers. Can be dispersed, but in some cases, using a neutral salt or alkali salt as an electrolyte, subjected to a mild electrolytic oxidation treatment with an electric quantity of 20 C / g or less, and the surface oxygen concentration involved in the adhesion with the resin. The (O / C ratio) can be increased to further improve the adhesive strength.
【００１２】[0012]
【実施例】次に実施例により本発明をさらに詳細に説明
するが、これらは本発明の範囲を制限するものではな
い。なお、ＩＬＳＳの測定は、得られた繊維をエポキシ
樹脂（油化シェル社製「エピコート８２８」）１００重
量部と三フッ化ホウ素のモノアミン３重量部との混合
物）に含浸し、金型内に積層し、３ｋｇ／ｃｍ2 の圧力
でプレスした状態で１００℃から１７０℃まで昇温し、
１時間加熱して一方向強化複合物（繊維含有率６０容量
％，厚み２ｍｍ，長さ（ｄ）１５ｍｍ）を作成し、スパ
ン長さ（Ｌ）＝４ｄにて実施した。The present invention will now be described in more detail by way of examples, which should not be construed as limiting the scope of the present invention. The ILSS was measured by impregnating the obtained fiber with a mixture of 100 parts by weight of an epoxy resin (“Epicoat 828” manufactured by Yuka Shell Co., Ltd.) and 3 parts by weight of a boron trifluoride monoamine. Laminate and press at a pressure of 3 kg / cm 2 to raise the temperature from 100 ° C to 170 ° C,
It was heated for 1 hour to prepare a unidirectionally reinforced composite (fiber content 60% by volume, thickness 2 mm, length (d) 15 mm), and span length (L) = 4 d.
【００１３】実施例１ 目付0.２９８５ｇ／ｍ，引張強度３２８ｋｇｆ／ｍ
ｍ2 ，引張弾性率５1.６×１０3 ｋｇｆ／ｍｍ2 ，ＩＬ
ＳＳ3.６ｋｇｆ／ｍｍ2 を有する石油ピッチ系炭素繊維
（焼成温度２３００℃）を用い、0.０５Ｎの硫酸水溶液
を電解液とし、１００クーロン／ｇの電気量を通電しな
がら、陽極酸化処理を行った。この表面処理糸を空気雰
囲気中３２０℃の管状炉を通過させて処理したのち、Ｃ
ＶＤ処理室に導入し、１０-3ｔｏｒｒの減圧下で脱気し
たのち、キャリアーガス（アルゴンガス）を導入して常
圧とし、さらに１１００℃に加熱した。そののち、メタ
ン１０cc／分，キャリアーガスとしてアルゴンガスを２
００cc／分流しながら、常圧にてＣＶＤによる被覆を２
５ｃｍ／分の速度で巻き取りながら行った。処理したス
トランドは目付0.３０１７ｇ／ｍ，引張強度３５２ｋｇ
ｆ／ｍｍ2，引張弾性率５1.３×１０3 ｋｇｆ／ｍ
ｍ2 ，ＩＬＳＳ6.３ｋｇｆ／ｍｍ2 であり、破壊様式は
層間破壊であった。Example 1 basis weight 0.2985 g / m, tensile strength 328 kgf / m
m 2 , tensile elastic modulus 51.6 × 10 3 kgf / mm 2 , IL
Using petroleum pitch-based carbon fiber having SS 3.6 kgf / mm 2 (calcination temperature 2300 ° C.), anodizing treatment is performed while using 0.05 N sulfuric acid aqueous solution as an electrolytic solution and energizing 100 coulomb / g of electricity. It was The surface-treated yarn was treated by passing through a tubular furnace at 320 ° C. in an air atmosphere, and then C
After being introduced into a VD treatment chamber and deaerated under a reduced pressure of 10 −3 torr, a carrier gas (argon gas) was introduced to bring it to normal pressure, and further heated to 1100 ° C. After that, 10 cc / min of methane and 2 argon gas as carrier gas
Coating by CVD under atmospheric pressure while flowing 00 cc / minute 2
It was carried out while winding at a speed of 5 cm / min. The treated strand has a basis weight of 0.3017 g / m and a tensile strength of 352 kg.
f / mm 2 , tensile modulus 51.3 × 10 3 kgf / m
m 2 , ILSS 6.3 kgf / mm 2 , and the failure mode was interlayer failure.
【００１４】実施例２ 実施例１の炭素繊維を使用し、同様に陽極酸化処理を行
ったのち、電気量１００クーロン／ｇで陰極酸化処理を
行った以外は、実施例１と同様な操作を行った。処理し
たストランドは目付0.３０３０ｇ／ｍ，引張強度３６０
ｋｇｆ／ｍｍ2，引張弾性率５1.８×１０3 ｋｇｆ／ｍ
ｍ2 ，ＩＬＳＳ7.０ｋｇｆ／ｍｍ2 であり、破壊様式は
層間破壊であった。Example 2 The same operation as in Example 1 was carried out except that the carbon fiber of Example 1 was used, and similarly anodized, and then anodized at an electric quantity of 100 coulomb / g. went. The treated strand has a basis weight of 0.3030 g / m and a tensile strength of 360.
kgf / mm 2 , tensile elastic modulus 51.8 × 10 3 kgf / m
m 2 , ILSS 7.0 kgf / mm 2 , and the failure mode was interlayer failure.
【００１５】実施例３ 実施例２で作成した表面処理糸を、0.０５Ｎ水酸化ナト
リウム水溶液を電解液として、２０クーロン／ｇの電気
量を通電して陽極酸化処理した。処理したストランドは
引張強度３５５ｋｇｆ／ｍｍ2 ，引張弾性率５1.５×１
０3 ｋｇｆ／ｍｍ2 ，ＩＬＳＳ8.０ｋｇｆ／ｍｍ2 であ
り、破壊様式は層間破壊であった。Example 3 The surface-treated yarn prepared in Example 2 was anodized by applying an electric quantity of 20 coulomb / g using a 0.05N sodium hydroxide aqueous solution as an electrolytic solution. The treated strand has a tensile strength of 355 kgf / mm 2 and a tensile modulus of 51.5 × 1.
0 3 kgf / mm 2, is a ILSS8.0kgf / mm 2, failure mode was interlaminar fracture.
【００１６】[0016]
【発明の効果】本発明によると、ピッチ系炭素繊維を電
解酸化処理したのち、その表面をＣＶＤ法により非晶質
炭素で被覆することによって、樹脂との接着強度が改善
された高強度，高弾性の表面改質炭素繊維が容易に得ら
れる。本発明の方法で得られた表面改質炭素繊維は、特
にＣＦＲＰ用の強化材として好適に用いられる。According to the present invention, the pitch-based carbon fiber is electrolytically oxidized and then the surface thereof is coated with amorphous carbon by the CVD method to improve the adhesive strength with the resin. Elastic surface-modified carbon fibers are easily obtained. The surface-modified carbon fiber obtained by the method of the present invention is preferably used as a reinforcing material for CFRP.
Claims (6)
不融化したのち、不活性ガス雰囲気下で焼成してなる炭
素繊維を電気量５０クーロン／ｇ以上で電解酸化処理
し、次いで処理された炭素繊維の表面を炭化水素ガスを
原料とする化学気相蒸着法により非晶質炭素で被覆する
ことを特徴とする表面改質炭素繊維の製造方法。1. A carbon fiber obtained by infusibilizing pitch fiber obtained by spinning pitch and then firing in an inert gas atmosphere, is subjected to electrolytic oxidation treatment at an electric quantity of 50 coulomb / g or more, and is then treated. A method for producing a surface-modified carbon fiber, which comprises coating the surface of the carbon fiber with amorphous carbon by a chemical vapor deposition method using a hydrocarbon gas as a raw material.
相蒸着法により非晶質炭素を析出させる温度以上の温度
にて焼成されたものである請求項１記載の表面改質炭素
繊維の製造方法。2. The surface-modified carbon fiber according to claim 1, wherein the carbon fiber subjected to the electrolytic oxidation treatment is fired by a chemical vapor deposition method at a temperature higher than a temperature at which amorphous carbon is deposited. Production method.
理を行う請求項１又は２記載の表面改質炭素繊維の製造
方法。3. The method for producing a surface-modified carbon fiber according to claim 1, wherein the electrolytic oxidation treatment is performed using an inorganic acid as an electrolyte.
繊維を陽極とする電解酸化処理と炭素繊維を陰極とする
電解酸化処理を交互に行う請求項１記載の表面改質炭素
繊維の製造方法。4. The method for producing a surface-modified carbon fiber according to claim 1, wherein in the electrolytic oxidation treatment of carbon fiber, an electrolytic oxidation treatment using carbon fiber as an anode and an electrolytic oxidation treatment using carbon fiber as a cathode are alternately performed.
ス雰囲気下、３５０℃以下の温度で常圧又は減圧にて処
理したのち、処理された炭素繊維の表面を化学気相蒸着
法により非晶質炭素で被覆する請求項１記載の表面改質
炭素繊維の製造方法。5. The electrolytically-oxidized carbon fiber is treated in an oxygen-containing gas atmosphere at a temperature of 350 ° C. or lower at atmospheric pressure or reduced pressure, and the surface of the treated carbon fiber is amorphous by a chemical vapor deposition method. The method for producing a surface-modified carbon fiber according to claim 1, wherein the surface-modified carbon fiber is coated with high quality carbon.
造方法で得られた表面改質炭素繊維を、更に電解酸化処
理することを特徴とする表面改質炭素繊維の製造方法。6. A method for producing a surface-modified carbon fiber, which comprises subjecting the surface-modified carbon fiber obtained by the production method according to claim 1 to electrolytic oxidation treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4221327A JPH0665858A (en) | 1992-08-20 | 1992-08-20 | Production of surface-modified carbon fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4221327A JPH0665858A (en) | 1992-08-20 | 1992-08-20 | Production of surface-modified carbon fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0665858A true JPH0665858A (en) | 1994-03-08 |
Family
ID=16765070
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4221327A Pending JPH0665858A (en) | 1992-08-20 | 1992-08-20 | Production of surface-modified carbon fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0665858A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0813255A (en) * | 1994-07-05 | 1996-01-16 | Mitsubishi Chem Corp | Carbon fiber having ultra-high modulus of elasticity and high strength and its production |
| US6501267B1 (en) | 1998-08-06 | 2002-12-31 | Mitsubishi Heavy Industries, Ltd. | Eddy-current flaw detector probe |
| JPWO2020031713A1 (en) * | 2018-08-06 | 2021-08-10 | 株式会社クレハ環境 | Manufacturing method of coating layer-containing reinforcing material and coating layer-containing reinforcing material |
| CN114369955A (en) * | 2021-12-30 | 2022-04-19 | 山东仁丰特种材料股份有限公司 | Method for preparing high-performance electromagnetic shielding paper by using carbon fibers |
| CN115595792A (en) * | 2022-10-27 | 2023-01-13 | 陕西天策新材料科技有限公司（Cn） | Treatment method of ultrahigh-modulus asphalt-based graphite fiber |
-
1992
- 1992-08-20 JP JP4221327A patent/JPH0665858A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0813255A (en) * | 1994-07-05 | 1996-01-16 | Mitsubishi Chem Corp | Carbon fiber having ultra-high modulus of elasticity and high strength and its production |
| US6501267B1 (en) | 1998-08-06 | 2002-12-31 | Mitsubishi Heavy Industries, Ltd. | Eddy-current flaw detector probe |
| JPWO2020031713A1 (en) * | 2018-08-06 | 2021-08-10 | 株式会社クレハ環境 | Manufacturing method of coating layer-containing reinforcing material and coating layer-containing reinforcing material |
| CN114369955A (en) * | 2021-12-30 | 2022-04-19 | 山东仁丰特种材料股份有限公司 | Method for preparing high-performance electromagnetic shielding paper by using carbon fibers |
| CN114369955B (en) * | 2021-12-30 | 2023-04-25 | 山东仁丰特种材料股份有限公司 | Method for preparing high-performance electromagnetic shielding paper by using carbon fiber |
| CN115595792A (en) * | 2022-10-27 | 2023-01-13 | 陕西天策新材料科技有限公司（Cn） | Treatment method of ultrahigh-modulus asphalt-based graphite fiber |
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