JPH07150419A - Production of carbon fiber according to vapor process - Google Patents
Production of carbon fiber according to vapor processInfo
- Publication number
- JPH07150419A JPH07150419A JP32604293A JP32604293A JPH07150419A JP H07150419 A JPH07150419 A JP H07150419A JP 32604293 A JP32604293 A JP 32604293A JP 32604293 A JP32604293 A JP 32604293A JP H07150419 A JPH07150419 A JP H07150419A
- Authority
- JP
- Japan
- Prior art keywords
- carbon fiber
- droplets
- producing
- furnace
- fibers
- 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.)
- Granted
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は炭素繊維、より詳しくは
有機化合物の熱分解による気相成長法によって炭素繊維
を製造する方法に関するBACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to carbon fiber, and more particularly to a method for producing carbon fiber by vapor phase growth method by thermal decomposition of organic compounds.
【０００２】[0002]
【従来の技術】炭素繊維を気相成長法で製造する方法
は、加熱炉内で有機化合物を熱分解して炭素繊維を１工
程で得ることの出来る優れた方法であるが、工業的な生
産性に問題があり改善改良がなされてきた。例えば初め
はセラミック基板に遷移金属の超微粒子を付着させてか
ら有機化合物を供給し分解させ長時間成長させて比較的
太く長い気相法炭素繊維を製造する方法であった。この
方法は良好な物性の炭素繊維が得られるが、太くなると
反応速度が低く、工業生産には不十分であった。この生
産性を改善するために例えば、特開昭58-180615 号公報
では、遷移金属あるいはその化合物の超微粉末を有機化
合物の熱分解帯域に浮遊するように存在させる流動法が
提案されている。更に流動法として特開昭63-92726号公
報にはこの金属粒子を2 〜30ｎｍとなるように調整し，
これを有機化合物の液中に分散し，液滴にして炉内に供
給するがその際に液滴の径を調整することが好ましいと
述べられている。また、同じく特開昭62-53419号公報に
は液滴の径を30μｍ以下にするのが良いと述べられてい
る。これらの場合液滴は通常図２に示すように反応帯域
全体に広がる様に供給されている。また特公平４−２４
３２０にはフェロセン等の遷移金属の有機化合物を気相
にして炭素繊維の析出帯域に導き，そこで熱分解し，生
成した金属の超微粒子を基板上に析出させ，そこで炭素
繊維を成長させる方法が開示されている。2. Description of the Related Art A method for producing carbon fibers by vapor phase growth is an excellent method for pyrolyzing an organic compound in a heating furnace to obtain carbon fibers in one step. There is a problem with the sex and improvements have been made. For example, the first method was to deposit ultrafine particles of a transition metal on a ceramic substrate, then supply an organic compound to decompose it and grow it for a long time to produce a relatively thick and long vapor grown carbon fiber. Although carbon fibers having good physical properties can be obtained by this method, the reaction rate becomes slower as the fiber becomes thicker, which is insufficient for industrial production. In order to improve this productivity, for example, Japanese Patent Application Laid-Open No. 58-180615 proposes a flow method in which an ultrafine powder of a transition metal or its compound is made to exist so as to be suspended in a thermal decomposition zone of an organic compound. . Further, as a flow method, in JP-A-63-92726, the metal particles were adjusted to have a particle size of 2 to 30 nm,
It is described that this is dispersed in a liquid of an organic compound and is made into liquid droplets and supplied into the furnace. At that time, it is preferable to adjust the diameter of the liquid droplets. Further, similarly, Japanese Patent Application Laid-Open No. 62-53419 describes that the diameter of the liquid droplets should be 30 μm or less. In these cases, the droplets are usually supplied so as to spread over the entire reaction zone as shown in FIG. In addition,
In 320, an organic compound of a transition metal such as ferrocene is converted into a vapor phase and introduced into a carbon fiber deposition zone, where it is thermally decomposed, and ultrafine particles of the produced metal are deposited on a substrate, where the carbon fiber is grown. It is disclosed.
【０００３】[0003]
【発明が解決しようとする課題】流動法では遷移金属ま
たはその化合物を含む有機化合物（原料）は炉の長さ方
向と平行に供給され炭素繊維は浮遊状態で生成し，多く
はそのまま炉外に取り出されるので反応時間が短いため
に反応収率が低く、また、結晶成長が不十分で炭素繊維
の太さや長さが小さく良好な炭素繊維が得られなかっ
た。特公平４−２４３２０の方法ではフェロセン等を基
板上に集中するように吹き付けていないため金属微粒子
の基板上における濃度，利用率が低くまた原料はガス化
して炉内に導かれるのでガス濃度が炉内に均一となり，
特に基板上における微粒子の濃度及びその微粒子周辺の
原料濃度を高くすることが出来ず，これらの結果として
基板上における炭素繊維の収量が上がらない。In the flow method, an organic compound (raw material) containing a transition metal or its compound is supplied in parallel with the length direction of the furnace, and carbon fibers are produced in a floating state, and most of them are left outside the furnace as they are. Since it was taken out, the reaction time was short because the reaction time was short, and the crystal growth was insufficient, and the thickness and length of the carbon fiber were small, and good carbon fiber could not be obtained. In the method of Japanese Patent Publication No. 4-24320, since ferrocene or the like is not sprayed so as to concentrate on the substrate, the concentration and utilization rate of the metal fine particles on the substrate are low, and the raw material is gasified and introduced into the furnace, so that the gas concentration is high. Becomes uniform within
In particular, the concentration of fine particles on the substrate and the raw material concentration around the fine particles cannot be increased, and as a result, the yield of carbon fibers on the substrate cannot be increased.
【０００４】原料を液滴で反応領域に供給する場合は反
応に要するエネルギーは輻射熱やキャリヤーガスの流動
伝熱で吸収することになる。その際、液滴が反応領域ま
で温度が上昇するためには、まず液体の蒸発温度までに
要する熱量と蒸発熱が必要であり、熱供給が不十分の場
合には部分的に温度低下を起こし、その結果炭化速度を
下げ、反応率、繊維成長速度が低下し充分な長さの繊維
が得られない。従ってこれらの問題点を解決するために
は、繊維の滞留時間を長くすること、反応温度の伝達速
度をあげるために、流動伝熱、輻射伝熱のみならず、炉
壁からの伝導伝熱を併用する方法を採用することが望ま
しい。本発明は所定の滞留時間，炉壁からの伝熱及び炭
素繊維生成帯域での原料の高濃度化により炭素繊維の成
長，収率の増大を図り，かつ熱伝導等の特性の優れた炭
素繊維を提供することを目的とする。When the raw material is supplied in droplets to the reaction region, the energy required for the reaction is absorbed by radiant heat or flow heat transfer of the carrier gas. At that time, in order for the temperature of the droplet to rise to the reaction region, first, the amount of heat and the heat of vaporization required up to the vaporization temperature of the liquid are required, and if the heat supply is insufficient, the temperature will partially drop. As a result, the carbonization rate is lowered, the reaction rate and the fiber growth rate are lowered, and a fiber having a sufficient length cannot be obtained. Therefore, in order to solve these problems, in order to increase the residence time of the fiber and increase the reaction temperature transfer rate, not only flow heat transfer and radiant heat transfer but also heat transfer from the furnace wall is used. It is desirable to adopt the method of combined use. The present invention aims to increase the growth and yield of carbon fiber by a predetermined residence time, heat transfer from the furnace wall and high concentration of the raw material in the carbon fiber production zone, and carbon fiber having excellent characteristics such as heat conduction. The purpose is to provide.
【０００５】[0005]
【課題を解決するための手段】上記課題を解決するため
本発明では基板の代わりに伝熱をよくし，かつ所定の滞
留時間が取れるように炉壁に炭素繊維を生成させ保持す
る方法を採用し，また原料の供給は液滴にして炉壁に向
けて吹き付けて行うことにより炉壁近傍の原料濃度を高
くしたものである。即ち，本発明は遷移金属の超微粒子
をシードとし，有機化合物の熱分解により炭素繊維を製
造する方法において，遷移金属またはその化合物を含有
する有機化合物の微小液滴を加熱炉壁面に向けて連続的
または間欠的に吹き付けながら反応させ，炉壁面に炭素
繊維を生成させ，さらにその炭素繊維上に分岐状の炭素
繊維を生成させ，これを間欠的に掻き取ることを特徴と
する気相法炭素繊維の製造方法である。またここで得ら
れた炭素繊維を１０００℃以上で熱処理することが出
来、さらに熱処理後粉砕することが望ましい。In order to solve the above problems, the present invention employs a method of improving the heat transfer instead of the substrate and generating and holding carbon fibers on the furnace wall so that a predetermined residence time can be obtained. In addition, the raw material is supplied in the form of droplets and sprayed toward the furnace wall to increase the concentration of the raw material near the furnace wall. That is, the present invention uses a transition metal ultrafine particle as a seed and produces carbon fibers by thermal decomposition of an organic compound. In the method, fine droplets of a transition metal or an organic compound containing the compound are continuously directed toward a wall surface of a heating furnace. Characterized by vaporization by intermittent or intermittent spraying to generate carbon fibers on the furnace wall surface, and then branched carbon fibers on the carbon fibers, which are intermittently scraped off It is a method for producing fibers. Further, the carbon fiber obtained here can be heat-treated at 1000 ° C. or higher, and it is desirable that the carbon fiber is further crushed after the heat treatment.
【０００６】以下この発明を詳しく説明する。シードで
あり触媒となる遷移金属またはその化合物は周期律表第
IVa ，Ｖa ，VIa ，VIIa，VIII族の元素及びそれらの合
金や混合物及びその無機及び有機化合物が適する。なか
でも遷移金属元素の超微粒子シード（種）となる遷移金
属及びその化合物には、Ｆｅ，Ｎｉ，Ｃｏ等の超微粉
（30ｎｍ以下）、フェロセン、ニッケルセンなどの有機
化合物が好ましい。Ｆｅ，Ｎｉ，Ｃｏ等の超微粉は製法
上や凝集等の問題があるが，フェロセン等の有機化合物
は熱分解によりＦｅ等の超微粒子が生成するので特に好
ましい。触媒としての遷移金属の含有量としては、有機
化合物の炭素量（フェロセン等の使用の場合はその炭素
を含めた合計量）に対して0.03〜10.0重量％好ましくは
0.1 〜5.0 重量％が良い。The present invention will be described in detail below. The transition metal or its compound that serves as a seed and a catalyst is
IVa, Va, VIa, VIIa, VIII elements and their alloys and mixtures and their inorganic and organic compounds are suitable. Among them, as the transition metal and its compound which become the ultrafine particle seed of the transition metal element, ultrafine powder (30 nm or less) such as Fe, Ni, Co, or organic compound such as ferrocene or nickelcene is preferable. Although ultrafine powders of Fe, Ni, Co and the like have problems in manufacturing method and aggregation, organic compounds such as ferrocene are particularly preferable because ultrafine particles of Fe and the like are generated by thermal decomposition. The content of the transition metal as a catalyst is preferably 0.03 to 10.0 wt% with respect to the carbon amount of the organic compound (in the case of using ferrocene or the like, the total amount including the carbon).
0.1 to 5.0% by weight is good.
【０００７】炭素繊維の原料となる有機化合物は、ベン
ゼン、トルエン、キシレン、メタノール、エタノール、
ナフタレン、フェナントレン、シクロプロパン、シクロ
ペンテン、シクロヘキサンその他の有機化合物及びそれ
らの混合物や揮発油、灯油、等も使用可能である。中で
もベンゼン、トルエン、キシレン等の芳香族化合物が特
に好ましい。この有機化合物に前記遷移金属の超微粒子
あるいはフェロセン等の化合物を分散または溶解して液
滴状で供給する。有機化合物は全量この様な液滴にして
もよいが，１部を液滴として用い，残部は液状あるいは
ガス状で別に供給することも可能である。Organic compounds used as raw materials for carbon fibers include benzene, toluene, xylene, methanol, ethanol,
It is also possible to use naphthalene, phenanthrene, cyclopropane, cyclopentene, cyclohexane and other organic compounds and mixtures thereof, volatile oil, kerosene and the like. Among them, aromatic compounds such as benzene, toluene and xylene are particularly preferable. Ultrafine particles of the transition metal or a compound such as ferrocene is dispersed or dissolved in this organic compound and supplied in the form of droplets. The whole amount of the organic compound may be in the form of droplets as described above, but it is also possible to use one part as droplets and supply the rest separately in liquid or gas form.
【０００８】結晶の成長速度を高めるためには触媒（シ
ード）表面近傍の有機化合物の濃度を高める必要があ
る。原料液を気化し、気体で供給する方法の場合は触媒
の表面を含めて反応器内の原料濃度は平均濃度となる。
しかし、液滴で供給すればそこから微粒子が生じ同時に
液が蒸発するため触媒近傍の原料有機化合物濃度はかな
り高くなり、結晶成長速度を高める結果となる。液滴の
供給方法も本発明の特徴の一つであり，本発明では液滴
を炉壁に向けて連続的または間欠的に供給するようにし
た。炉は通常外熱方式なので炉内の熱は炉壁から輻射ま
たはガスの伝熱によって供給される。従って，液滴が炉
壁やその近くにある方が加熱にとって有利である。炉壁
に炭素繊維が生成し炉壁を覆った後は液滴はこの繊維上
に吹き付けられるが，この炭素繊維は熱伝導度が非常に
大きいので，液滴の加熱に不利になることはない。In order to increase the crystal growth rate, it is necessary to increase the concentration of the organic compound near the surface of the catalyst (seed). In the case of vaporizing the raw material liquid and supplying it as a gas, the raw material concentration in the reactor including the surface of the catalyst becomes an average concentration.
However, if the liquid is supplied in the form of liquid droplets, fine particles are generated from the liquid and the liquid is evaporated at the same time, so that the concentration of the raw material organic compound in the vicinity of the catalyst becomes considerably high, resulting in an increase in crystal growth rate. The method of supplying droplets is also one of the features of the present invention, and in the present invention, the droplets are supplied toward the furnace wall continuously or intermittently. Since the furnace is usually of the external heat type, the heat in the furnace is supplied from the wall of the furnace by heat transfer of radiation or gas. Therefore, it is advantageous for heating that the droplets are at or near the furnace wall. After carbon fibers are generated on the furnace wall and cover the furnace wall, the droplets are sprayed onto this fiber, but this carbon fiber has a very high thermal conductivity, so there is no disadvantage in heating the droplets. .
【０００９】熱伝導性が良くなることによって繊維の成
長が速まり，また炉壁に繊維が生成した後はそれに液滴
を吹き付け，分岐を含む繊維の生成，さらに液滴の吹き
付けとが連続的におこなわれるが，集積した繊維間ある
いは繊維上に微粒子が生じるので，微粒子の利用率が高
まり，それが収率増加の一因になっているとも考えられ
る。液滴を供給する方法は遷移金属またはその化合物を
含む有機化合物をスプレーノズルを用いて噴霧する方法
が適する。噴霧はこの液滴をそのまま噴霧してもよい
が，キャリヤーガスとして通常水素ガスが使用されるの
で，この水素ガスを一緒に噴霧出来るスプレーノズルを
用いて噴霧するのが好ましい。噴霧を炉壁に吹き付ける
ようにするにはノズルの先端の流体の通路を放射状に広
げるように傾斜した構造とする。The improvement of the thermal conductivity accelerates the growth of the fibers, and after the fibers are formed on the furnace wall, the droplets are sprayed on the furnace wall to form the fibers including the branch, and further the droplets are sprayed continuously. However, since the fine particles are generated between or on the accumulated fibers, the utilization rate of the fine particles is increased, which is considered to be one of the reasons for the increased yield. As a method of supplying droplets, a method of spraying an organic compound containing a transition metal or its compound using a spray nozzle is suitable. The droplets may be sprayed as they are, but since hydrogen gas is usually used as a carrier gas, it is preferable to use a spray nozzle capable of spraying this hydrogen gas together. In order to spray the spray on the furnace wall, the structure is inclined so that the fluid passage at the tip of the nozzle is radially expanded.
【００１０】図１に本発明の実施に用いられる装置の概
略図を示す。図に於て１は加熱炉で，これは横型でも不
可能ではないが炉壁に堆積した繊維の掻き落しの容易さ
や炉壁の周囲が同一条件になること等により図示のよう
に縦型が好ましい。２は加圧式分散噴霧ノズルで流体通
路の下部２１は傾斜し流体が放射状に広がるような構造
になっている。この通路下部２１は例えば数個の小孔が
設けられている構造である。フェロセン等を溶解した液
体はキャリヤーガスとともにノズルに供給され，キャリ
ヤーガスの圧力で噴霧される。図で３は噴霧された流体
でその頂角は３０〜１２０°が好ましい。FIG. 1 shows a schematic diagram of an apparatus used for carrying out the present invention. In the figure, 1 is a heating furnace, which is not impossible even with a horizontal type, but as shown in the figure, the vertical type is used because of the ease of scraping the fibers deposited on the furnace wall and the same conditions around the furnace wall. preferable. Reference numeral 2 is a pressure-type dispersion spray nozzle, and the lower portion 21 of the fluid passage is inclined so that the fluid spreads radially. The passage lower portion 21 has a structure in which, for example, several small holes are provided. The liquid in which ferrocene and the like are dissolved is supplied to the nozzle together with the carrier gas and atomized at the pressure of the carrier gas. In the figure, 3 is a sprayed fluid, and its apex angle is preferably 30 to 120 °.
【００１１】キャリヤーガスは水素（Ｈ2 ）ガスをはじ
めとする還元性のガスが好ましく遷移金属の触媒として
の活性発現及び維持のために、原料及び触媒を熱分解帯
域に供給する際に用いる。キャリヤーガスの量は炭素源
である有機化合物１. ０モル部に対し1 〜70モル部が適
当である。反応領域に導入する液滴の大きさは触媒の核
の大きさに関係し、繊維の太さ、長さや、反応率に影響
する。触媒の核の大きさが大きいと繊維の太さが太くな
り、長さが短く、逆に小さいと細く弱い繊維となる。ま
た液滴の粒子径が大きいと多量の蒸発エネルギーを必要
とするため、部分的な温度低下を来たし、反応率の低下
や炭素繊維の析出速度の低下につながる。また小さすぎ
ると導入後すぐ蒸発し、壁面に到達する前に気化してし
まう割合が高くなる。以上のような点を考慮すると噴霧
された微小液滴の径は７０〜２００ミクロンが適当であ
る。The carrier gas is preferably a reducing gas such as hydrogen (H 2 ) gas, and is used when the raw material and the catalyst are supplied to the thermal decomposition zone in order to exhibit and maintain the activity of the transition metal as a catalyst. The amount of the carrier gas is appropriately 1 to 70 parts by mol with respect to 1.0 part by mol of the organic compound which is the carbon source. The size of the droplet introduced into the reaction region is related to the size of the nucleus of the catalyst, and affects the thickness and length of the fiber and the reaction rate. If the size of the core of the catalyst is large, the fiber becomes thick, and if the length is short, on the contrary, if it is small, the fiber becomes thin and weak. Further, if the particle diameter of the droplet is large, a large amount of evaporation energy is required, resulting in a partial temperature drop, leading to a decrease in the reaction rate and a decrease in the carbon fiber deposition rate. On the other hand, if it is too small, the rate of evaporation immediately after introduction and vaporization before reaching the wall surface becomes high. Considering the above points, it is appropriate that the diameter of the sprayed microdroplets is 70 to 200 microns.
【００１２】液滴の噴霧は連続的または間欠的に行われ
る。従って最初炉壁面に炭素繊維が生成しさらにその繊
維上に噴霧されるので，そこで生成する繊維の多くは分
岐状となる。この様にして炉壁面で繊維の生成成長が起
こり，炉の内壁に堆積する。これを間欠的に掻き落と
す。掻き落とす間隔は堆積状況を見て決めるが１０秒か
ら１５分位の範囲が適当である。掻き落とす方法は棒の
先端にリングを取り付けた冶具を用いることが出来る
（実開昭62-93379）。炉の内壁の温度は通常の場合と変
わりなく８００〜１３００℃程度である。本発明によっ
て得られる炭素繊維の大部分は太さ０. ０５〜０. ５ミ
クロン、長さ１〜１００μである。The droplets are sprayed continuously or intermittently. Therefore, since carbon fibers are first formed on the furnace wall surface and are further sprayed on the fibers, most of the fibers formed there are branched. In this way, fibers grow and grow on the furnace wall, and deposit on the inner wall of the furnace. This is scraped off intermittently. The scraping interval is determined by looking at the deposition condition, but a range of 10 seconds to 15 minutes is appropriate. For the scraping method, a jig with a ring attached to the tip of the rod can be used (Shokaisho 62-93379). The temperature of the inner wall of the furnace is about 800 to 1300 ° C, which is the same as in the usual case. Most of the carbon fibers obtained by the present invention have a thickness of 0.05 to 0.5 μm and a length of 1 to 100 μm.
【００１３】[0013]
【作用】空間生産性を向上させるべく原料を炉内分解帯
域全体に供給する場合には、この熱分解帯域に炉の半径
方向さらには長手方向に温度分布が生じ易く、それが不
均一の原因となる。原料の供給は可能な限り均一な温度
ゾーンへ行うことが望ましいが、反応中の吸熱または発
熱反応により外部加熱を制御したとしてもより均一な温
度ゾーンを広く維持することは困難である。本発明にお
いては炉壁面で炭素繊維を生成させることにより，伝熱
方式が輻射のみならず、炉壁からの伝導方式が導入でき
る。炭素繊維の熱伝導性は著しく大きく、輻射に加え
て、伝導が導入されることによって、流動法の様な炉内
全体で炭素繊維を生成させる場合に比べて，熱の伝熱が
よく均一性が良好になり反応性及び繊維の成長性が良く
なる。When the raw material is supplied to the entire decomposition zone in the furnace in order to improve the space productivity, temperature distribution is likely to occur in the thermal decomposition zone in the radial direction of the furnace and further in the longitudinal direction thereof, which causes non-uniformity. Becomes It is desirable to supply the raw material to a temperature zone as uniform as possible, but it is difficult to maintain a wider temperature zone even if external heating is controlled by an endothermic or exothermic reaction during the reaction. In the present invention, by producing carbon fibers on the wall surface of the furnace, not only the heat transfer method but also the conduction method from the furnace wall can be introduced. The thermal conductivity of carbon fiber is remarkably large, and by introducing conduction in addition to radiation, the heat transfer is better and more uniform than in the case where carbon fiber is generated throughout the furnace as in the flow method. And the reactivity and fiber growth are improved.
【００１４】また原料を液滴で供給することにより金属
の微粒子周辺の炭素化合物の濃度が高まり収率も向上す
る。触媒を含む原料は基板または基板上で成長している
炭素繊維の表面に吹き付けられ、蒸発反応していく過程
でその繊維の成長を促進すると共に、炭素繊維表面に結
晶核が新たに出来それを起点として、新たな成長が促進
される。これの繰り返しによって分岐状の気相法炭素繊
維が得られる。Further, by supplying the raw material in the form of droplets, the concentration of the carbon compound around the metal fine particles is increased and the yield is also improved. The raw material containing the catalyst is sprayed onto the substrate or the surface of the carbon fiber growing on the substrate, promoting the growth of the fiber in the process of evaporative reaction and forming new crystal nuclei on the surface of the carbon fiber. As a starting point, new growth is promoted. By repeating this, a branched vapor grown carbon fiber is obtained.
【００１５】[0015]
【実施例】以下添付図面を参照して、本発明の実施例及
び比較例によって本発明を詳細に説明する。 実施例 図１に示すように、縦型加熱炉（内径17.0cm，長さ150c
m ）１の頂部に、スプレーノズル２を取り付ける。加熱
炉１の炉内壁温度を1200℃に昇温・維持し、スプレーノ
ズル２から4 重量％のフェロセンを含有するベンゼンの
液体原料20g ／分を100L／分の水素ガスの流量で炉壁に
直接噴霧（スプレー）散布するように供給する。この時
のスプレー２の形状は円錐側面状（ラッパ状ないし傘
状）であり、ノズルの頂角θが60°である。このような
条件の下で、フェロセンは熱分解して鉄微粒子を作り、
これがシード（種）となってベンゼンの熱分解による炭
素から、炭素繊維を生成成長させた。本方法で成長した
気相法炭素繊維を５分間隔で掻き落としながら１時間に
わたって連続的に製造した。この炭素繊維の顕微鏡写真
（×5000）を図３に示す。得られた炭素繊維のうち約３
０ｇを2400℃で熱処理し、これをＰＰ樹脂（昭和電工株
式会社製：SMA410）に混ぜて、50wt％炭素繊維を含有す
る繊維強化プラスチックを製造した。この繊維強化プラ
スチックの体積比抵抗を測定したところ0.14Ωｃｍであ
った。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings by way of examples and comparative examples of the present invention. Example As shown in FIG. 1, a vertical heating furnace (inner diameter 17.0 cm, length 150 c
m) Install spray nozzle 2 on top of 1. The temperature of the inner wall of the heating furnace 1 was raised to 1200 ° C and maintained, and 20 g / min of the liquid raw material of benzene containing 4% by weight of ferrocene was sprayed directly from the spray nozzle 2 to the furnace wall at a flow rate of 100 L / min of hydrogen gas. Supply as a spray. The shape of the spray 2 at this time is a conical side surface shape (trumpet shape or umbrella shape), and the apex angle θ of the nozzle is 60 °. Under these conditions, ferrocene is pyrolyzed to make fine iron particles,
This served as a seed, and carbon fibers were produced and grown from the carbon by the thermal decomposition of benzene. The vapor grown carbon fiber grown by this method was continuously produced for 1 hour while scraping it off at intervals of 5 minutes. A micrograph (× 5000) of this carbon fiber is shown in FIG. About 3 of the carbon fibers obtained
0 g was heat-treated at 2400 ° C., and this was mixed with PP resin (Showa Denko KK: SMA410) to produce a fiber reinforced plastic containing 50 wt% carbon fiber. The volume resistivity of this fiber reinforced plastic was measured and found to be 0.14 Ωcm.
【００１６】比較例 使用するスプレーノズルを炉の直下全面にスプレーする
図２に示すようなタイプのものを用い、それ以外の製造
条件を上述した実施例の場合と同じとし、気相法炭素繊
維の製造を行った。その炭素繊維の顕微鏡写真（×500
0）を図４に示す。得られた炭素繊維約２０ｇを2400℃
で熱処理し、これを上述のＰＰ樹脂に混ぜて50wt％の炭
素繊維を含有する繊維強化プラスチックを同様に製造
し、体積比抵抗を測定したところ0.40Ωｃｍであった。
炭素繊維の顕微鏡写真から解るように、本発明にかかわ
る製造方法で得られた炭素繊維（図３）は比較例の炭素
繊維（図４）よりも分岐が多い。そして、炭素繊維強化
プラスチックではあるが、本発明の炭素繊維の方が導電
性がよい（比抵抗が小さい）。Comparative Example A spray nozzle used was a type as shown in FIG. 2 for spraying the entire surface just below the furnace, and the other manufacturing conditions were the same as those of the above-mentioned embodiment, and the vapor grown carbon fiber was used. Was manufactured. Micrograph of the carbon fiber (× 500
0) is shown in FIG. About 20 g of the obtained carbon fiber is 2400 ° C
Was heat treated, and this was mixed with the above-mentioned PP resin to produce a fiber reinforced plastic containing 50 wt% of carbon fiber in the same manner, and the volume resistivity was measured and found to be 0.40 Ωcm.
As can be seen from the micrograph of the carbon fiber, the carbon fiber (FIG. 3) obtained by the production method according to the present invention has more branches than the carbon fiber of the comparative example (FIG. 4). Although it is a carbon fiber reinforced plastic, the carbon fiber of the present invention has better conductivity (smaller specific resistance).
【００１７】[0017]
【発明の効果】以上説明したように、本発明に係わる製
造方法によって得られる炭素繊維はその形状が従来より
も均一性が良くなり、分枝が多い、そして繊維同志のつ
ながりが多いので導電性が向上し樹脂との分散性（混
合）も向上する。特に、複合材料中で導電性付与原料と
して機能するミクロ素材として有効な炭素繊維を提供す
ることが出来る。As described above, the carbon fiber obtained by the manufacturing method according to the present invention has a more uniform shape than the conventional one, has a large number of branches, and has a large number of fibers connected to each other. And the dispersibility (mixing) with the resin is also improved. In particular, it is possible to provide a carbon fiber effective as a micromaterial that functions as a raw material for imparting conductivity in a composite material.
【図１】本発明に用いられる気相法炭素繊維製造装置の
概略断面図である。FIG. 1 is a schematic cross-sectional view of a vapor grown carbon fiber production apparatus used in the present invention.
【図２】従来の気相法炭素繊維製造装置の概略断面図で
ある。FIG. 2 is a schematic sectional view of a conventional vapor grown carbon fiber manufacturing apparatus.
【図３】本発明に係わる製造方法による炭素繊維の形状
を示す顕微鏡写真である。FIG. 3 is a micrograph showing the shape of carbon fibers produced by the production method according to the present invention.
【図４】比較例の製造方法による炭素繊維の形状を示す
顕微鏡写真である。FIG. 4 is a micrograph showing the shape of carbon fibers produced by a manufacturing method of a comparative example.
１ 加熱炉 ２ 加圧分散式スプレーノズル ３ 本発明による噴霧状態 ４ 従来のスプレーノズル ５ 従来の噴霧状態 ２１ 傾斜したノズル小孔 θ 噴霧角度 1 Heating Furnace 2 Pressure Dispersion Type Spray Nozzle 3 Atomizing State According to the Present Invention 4 Conventional Spray Nozzle 5 Conventional Atomizing State 21 Inclined Nozzle Small Hole θ Spraying Angle
Claims (3)
有機化合物の熱分解により炭素繊維を製造する方法にお
いて，遷移金属またはその化合物を含有する有機化合物
の微小液滴を加熱炉壁面に向けて吹き付けながら反応さ
せ，炉壁面に炭素繊維を生成させ，さらにその炭素繊維
上に分岐状の炭素繊維を生成させ、これを間欠的に掻き
取ることを特徴とする気相法炭素繊維の製造方法。1. An ultrafine particle of a transition metal element is used as a seed,
In a method for producing carbon fiber by thermal decomposition of an organic compound, fine particles of a transition metal or an organic compound containing the compound are reacted while being sprayed toward the wall surface of a heating furnace to generate carbon fiber on the wall surface of the furnace. A method for producing a vapor grown carbon fiber, characterized in that branched carbon fibers are produced on the carbon fibers and the carbon fibers are scraped off intermittently.
０００℃以上で熱処理することを特徴とする気相法炭素
繊維の製造法。2. The vapor grown carbon fiber obtained in claim 1
A method for producing a vapor grown carbon fiber, which comprises heat treatment at 000 ° C. or higher.
繊維を粉砕することを特徴とする気相法炭素繊維の製造
法。3. A method for producing a vapor grown carbon fiber, which comprises pulverizing the vapor grown carbon fiber obtained in claim 1 or 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32604293A JP2778434B2 (en) | 1993-11-30 | 1993-11-30 | Method for producing vapor grown carbon fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP32604293A JP2778434B2 (en) | 1993-11-30 | 1993-11-30 | Method for producing vapor grown carbon fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07150419A true JPH07150419A (en) | 1995-06-13 |
| JP2778434B2 JP2778434B2 (en) | 1998-07-23 |
Family
ID=18183461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP32604293A Expired - Lifetime JP2778434B2 (en) | 1993-11-30 | 1993-11-30 | Method for producing vapor grown carbon fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2778434B2 (en) |
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| JP2006111870A (en) * | 2004-09-14 | 2006-04-27 | Showa Denko Kk | Electrically-conductive resin composition, method for producing the same, and use of the same |
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| JP2778434B2 (en) | 1998-07-23 |
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