JP2005228538A - Separator formation material for fuel cell - Google Patents

Separator formation material for fuel cell Download PDF

Info

Publication number
JP2005228538A
JP2005228538A JP2004034460A JP2004034460A JP2005228538A JP 2005228538 A JP2005228538 A JP 2005228538A JP 2004034460 A JP2004034460 A JP 2004034460A JP 2004034460 A JP2004034460 A JP 2004034460A JP 2005228538 A JP2005228538 A JP 2005228538A
Authority
JP
Japan
Prior art keywords
graphite
thermosetting resin
weight
fuel cell
tubes
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
Application number
JP2004034460A
Other languages
Japanese (ja)
Inventor
Yoshiaki Maeda
義明 前田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nok Corp
Original Assignee
Nok Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nok Corp filed Critical Nok Corp
Priority to JP2004034460A priority Critical patent/JP2005228538A/en
Publication of JP2005228538A publication Critical patent/JP2005228538A/en
Pending legal-status Critical Current

Links

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

<P>PROBLEM TO BE SOLVED: To provide a material capable of restraining a filling amount of expensive carbon nano-tubes, and of balancing low contact resistance with high flow formability, in a separator formation material for a fuel cell comprising graphite, a thermosetting resin and carbon nano-tubes. <P>SOLUTION: This separator formation material for a fuel cell is formed of a uniform mixture, containing 1-8 wt.% of carbon nano-tubes, of graphite, a thermosetting resin and the carbon nano-tubes. In particular, by a dispersion method of the carbon nano-tubes into a thermosetting resin-graphite mixture wherein the graphite is added to a dispersion processing liquid of the thermosetting resin, its soluble organic solvent and the carbon nano-tubes, they are agitated and thereafter the organic solvent is dried and removed, and the obtained mixture is kneaded and thereafter crushed, a thermosetting resin-graphite mixture with the carbon nano-tubes well dispersed can be provided without causing rupture of the carbon nano-tubes, whereby the desired separator formation material can be formed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、燃料電池用セパレータ成形材料に関する。さらに詳しくは、流動成形性にすぐれ、低接触抵抗値を示す成形品を与える燃料電池用セパレータ成形材料に関する。   The present invention relates to a fuel cell separator molding material. More specifically, the present invention relates to a fuel cell separator molding material that provides a molded article having excellent fluid moldability and a low contact resistance value.

炭素粉末と熱硬化性樹脂とを構成成分とし、樹脂成形法を主たる形状形成手段として形成された固体高分子型燃料電池のセパレータが提案されているが、樹脂に導電性フィラーを加える場合、導電性を向上させるために導電性フィラー量を増加させると、樹脂としての特性が失われ、成形性が著しく低下する。逆に、導電性フィラー量を少なくすると、所望の電気特性が得られず、また樹脂-黒鉛混合物では、セパレータ表面にスキン層が形成され、電極との接触抵抗が大きくなる。
特開平１０−３３４９２７号公報 A polymer electrolyte fuel cell separator has been proposed, which is composed of carbon powder and thermosetting resin as the main component, and the resin molding method is the main shape forming means. When the amount of the conductive filler is increased in order to improve the properties, the characteristics as a resin are lost, and the moldability is remarkably lowered. On the contrary, if the amount of the conductive filler is decreased, desired electrical characteristics cannot be obtained, and in the resin-graphite mixture, a skin layer is formed on the separator surface, and the contact resistance with the electrode is increased.
JP-A-10-334927

接触抵抗を低減する方法として、黒鉛粉末を熱硬化性樹脂およびカーボンナノファイバーからなる被覆層で被覆した粒状複合材の集合物で燃料電池用セパレータを成形することが提案されている。カーボンナノファイバーをこのようにして用いることにより、接触抵抗を低減することは可能であるが、ここで提案された成形材料は、黒鉛粉末55〜91質量％、硬化性樹脂9〜25質量％およびカーボンナノファイバー3〜30質量％、より好ましくは10〜20質量％からなる組成のものが好ましいとされており、カーボンナノファイバーの充填割合が比較的多いため、流動性が低下するばかりではなく、他の炭素材料と比べて高価なカーボンナノファイバーをより多く用いることは得策ではない。
特開２００３−３１７７３３号公報 As a method for reducing the contact resistance, it has been proposed to form a fuel cell separator with an aggregate of granular composite materials in which graphite powder is coated with a coating layer made of a thermosetting resin and carbon nanofibers. Although it is possible to reduce the contact resistance by using the carbon nanofibers in this way, the molding material proposed here is composed of 55 to 91% by mass of graphite powder, 9 to 25% by mass of curable resin, and It is said that a composition comprising 3 to 30% by mass of carbon nanofibers, more preferably 10 to 20% by mass is preferable, and since the filling ratio of carbon nanofibers is relatively large, not only fluidity is lowered, It is not a good idea to use more expensive carbon nanofibers than other carbon materials.
JP 2003-317733 A

カーボンナノファイバーとしてカーボンナノチューブを用いる場合、カーボンナノチューブ(以下、CNTと略称)は、アスペクト比が高く、高導電性が期待される素材であるが、繊維同士が絡み合った構造を有しており、それの分散は困難である。このため、従来の混練装置を単独で用い、CNTの分散を行うと、低せん断力では分散が不十分となり、目視でCNTの凝集が観測できる程度の分散不良となる。一方、高せん断力での分散では、分散性は向上するものの、CNTの破断が生ずるため、成形後に十分な導電性が得られないという問題がみられる。このように、CNTの分散性を制御することには、技術的な困難性がある。
成形加工 第１４巻第２号第１２６頁（２００２年） T.IEE Japan Vol.113-A,No.9,p.632(1993) When carbon nanotubes are used as carbon nanofibers, carbon nanotubes (hereinafter abbreviated as CNT) are materials that have a high aspect ratio and are expected to have high conductivity, but have a structure in which fibers are entangled with each other, It is difficult to disperse. For this reason, when a conventional kneading apparatus is used alone and CNTs are dispersed, the dispersion is insufficient with a low shear force, resulting in poor dispersion such that aggregation of CNTs can be visually observed. On the other hand, dispersion with a high shearing force improves dispersibility, but breaks CNT, and thus there is a problem that sufficient conductivity cannot be obtained after molding. Thus, there are technical difficulties in controlling the dispersibility of CNTs.
Forming Volume 14 Issue 2 Page 126 (2002) T.IEE Japan Vol.113-A, No.9, p.632 (1993)

また、固体高分子型燃料電池用セパレータにおいては、従来の黒鉛とフェノール樹脂とを有機溶媒を用いて混合した後、乾燥、粉砕して成形したセパレータでは、成形時に樹脂層の割合が多いスキン層が形成され、接触抵抗が高くなるという欠点がみられ、一方フェノール樹脂、黒鉛、CNTおよび有機溶媒を予備混合し、これを混練、粉砕して成形するという方法において、分散性を向上させるために高せん断力で混練を実施すると、CNTの破断が生ずるため、所望の電気特性が得られなくなること上述の如くである。   In the separator for polymer electrolyte fuel cells, the conventional graphite layer and phenol resin are mixed using an organic solvent, and then dried and pulverized to form a separator. In order to improve the dispersibility in the method in which phenol resin, graphite, CNT and organic solvent are premixed, kneaded, pulverized and molded, and the contact resistance is increased. As described above, when kneading is performed with a high shearing force, the CNT breaks, and the desired electrical characteristics cannot be obtained.

本発明の目的は、黒鉛、熱硬化性樹脂およびカーボンナノチューブよりなる燃料電池用セパレータ成形材料において、高価なカーボンナノチューブの充填量を少なく抑え、しかも低接触抵抗と高流動成形性とを両立せしめたものを提供することにある。   The object of the present invention is to suppress the filling amount of expensive carbon nanotubes in a fuel cell separator molding material comprising graphite, thermosetting resin and carbon nanotubes, and achieve both low contact resistance and high fluid moldability. To provide things.

かかる本発明の目的は、カーボンナノチューブを1〜8重量％含有する、黒鉛、熱硬化性樹脂およびカーボンナノチューブの均一混合物よりなる燃料電池用セパレータ成形材料によって達成される。   The object of the present invention is achieved by a fuel cell separator molding material comprising 1 to 8% by weight of carbon nanotubes and comprising a homogeneous mixture of graphite, thermosetting resin and carbon nanotubes.

本発明に係る燃料電池用セパレータ成形材料は、高価なカーボンナノチューブの充填量が1〜8重量％、好ましくは1〜5重量％と少なく、しかも低接触抵抗と高流動成形性とを両立せしめているので、固体高分子型燃料電池用セパレータ成形材料として好適に使用することができる。接触抵抗が低減するのは、分散したカーボンナノチューブが絶縁層である熱硬化性樹脂層中に入り込むためと考えられる。流動特性については、カーボンナノチューブ量が少なければ、それは成形時に樹脂と共に流動するが、量が増えるとその嵩高のために流動特性が低下するので、上記範囲が選択される。   The fuel cell separator molding material according to the present invention has a low carbon nanotube filling amount of 1 to 8% by weight, preferably 1 to 5% by weight, and achieves both low contact resistance and high fluid moldability. Therefore, it can be suitably used as a separator molding material for a polymer electrolyte fuel cell. The contact resistance is reduced because the dispersed carbon nanotubes enter the thermosetting resin layer which is an insulating layer. As for the flow characteristics, if the amount of carbon nanotubes is small, it flows with the resin during molding, but if the amount increases, the flow characteristics decrease due to its bulkiness, so the above range is selected.

特に、熱硬化性樹脂、それの可溶性有機溶媒およびカーボンナノチューブの分散処理液に黒鉛を加え、攪拌処理した後有機溶媒を乾燥除去し、得られた混合物を混練した後粉砕処理する、熱硬化性樹脂−黒鉛混合物中へのカーボンナノチューブの分散方法によって、黒鉛、熱硬化性樹脂およびカーボンナノチューブの均一混合物を形成せしめた場合には、カーボンナノチューブの破断を起さずに、それが良好に分散された熱硬化性樹脂-黒鉛混合物を得ることができるので、所望のセパレータ成形材料を形成することができる。   In particular, thermosetting resin, its soluble organic solvent and carbon nanotube dispersion treatment liquid is added with graphite, and after stirring treatment, the organic solvent is dried and removed, and the resulting mixture is kneaded and then pulverized. When a uniform mixture of graphite, thermosetting resin, and carbon nanotubes is formed by the method of dispersing carbon nanotubes in the resin-graphite mixture, the carbon nanotubes are well dispersed without causing breakage. In addition, since a desired thermosetting resin-graphite mixture can be obtained, a desired separator molding material can be formed.

黒鉛、熱硬化性樹脂およびカーボンナノチューブの均一混合物として、熱硬化性樹脂、それの可溶性有機溶媒およびカーボンナノチューブの分散処理液に黒鉛を加え、攪拌処理した後有機溶媒を乾燥除去し、得られた混合物を混練した後粉砕処理して、熱硬化性樹脂−黒鉛混合物中へのカーボンナノチューブを分散させる方法によって得られたものを用いることが好ましく、以下このような態様について説明する。   As a uniform mixture of graphite, thermosetting resin and carbon nanotube, graphite was added to the thermosetting resin, its soluble organic solvent and carbon nanotube dispersion treatment liquid, and after stirring treatment, the organic solvent was dried and removed. A mixture obtained by kneading and then pulverizing the mixture to disperse the carbon nanotubes in the thermosetting resin-graphite mixture is preferably used, and such an embodiment will be described below.

熱硬化性樹脂としては、有機溶媒に可溶性の熱硬化性樹脂、好ましくは液状の熱硬化性樹脂が用いられ、例えばフェノール樹脂、エポキシ樹脂、フラン樹脂、不飽和ポリエステル樹脂、ポリイミド樹脂等が挙げられ、コストや耐食性の点ですぐれたフェノール樹脂が好んで用いられる。フェノール樹脂は、レゾール型、ノボラック型のいずれであってもよい。   As the thermosetting resin, a thermosetting resin soluble in an organic solvent, preferably a liquid thermosetting resin is used, and examples thereof include a phenol resin, an epoxy resin, a furan resin, an unsaturated polyester resin, and a polyimide resin. Phenolic resins that are superior in terms of cost and corrosion resistance are preferably used. The phenol resin may be either a resol type or a novolac type.

有機溶媒は、熱硬化性樹脂を溶解可能で、しかも後の工程で蒸発、除去する必要があるため、揮発性の有機溶媒、例えばメタノール、エタノール等のアルコール類、アセトン、メチルエチルケトン等のケトン類が好んで用いられる。その使用量は、CNTを濡らして分散液を形成させる必要があるため、一般にはCNTに対して重量比で約50倍以上の割合で用いられる。一方、その上限割合は特に限定されないが、あまり多量に用いると溶媒除去や作業性が煩雑となるので、約200倍程度にとどめることが好ましい。   Since the organic solvent can dissolve the thermosetting resin and needs to be evaporated and removed in a later step, volatile organic solvents such as alcohols such as methanol and ethanol, and ketones such as acetone and methyl ethyl ketone are used. Preferably used. The amount used is generally used at a ratio of about 50 times or more by weight with respect to CNT because it is necessary to wet the CNT to form a dispersion. On the other hand, the upper limit ratio is not particularly limited, but if it is used too much, solvent removal and workability become complicated, so it is preferable to limit it to about 200 times.

熱硬化性樹脂と共に有機溶媒中に分散せしめるカーボンナノチューブとしては、アーク放電法、レーザー放電法、化学気相成長法などのいずれかの方法で作製されたものを用いることができ、多層カーボンナノチューブ、単層カーボンナノチューブ、カーボンナノファイバー等を用いることもできる。ただし、CNTは黒鉛と比べてサイズが小さく、CNTの充填量を増加させると材料の流動性が著しく悪化するようになる。また、黒鉛に比べても高価であるため、少量の充填量で使用することが好ましい。少量の充填量で導電性の効果を発現するためには、CNTの繊維径は細い方が良く、約500nm以下、好ましくは約100nm以下、さらに好ましくは約50nm以下の繊維径のものが用いられ、その繊維長については約500μm以下、好ましくは約1〜100μmのものが用いられる。   As carbon nanotubes dispersed in an organic solvent together with a thermosetting resin, those produced by any method such as arc discharge method, laser discharge method, chemical vapor deposition method can be used. Single-walled carbon nanotubes, carbon nanofibers, and the like can also be used. However, CNT is smaller in size than graphite, and increasing the CNT filling amount causes the fluidity of the material to deteriorate significantly. Further, since it is more expensive than graphite, it is preferable to use it with a small filling amount. In order to develop a conductive effect with a small filling amount, the fiber diameter of CNTs should be narrow, and those having a fiber diameter of about 500 nm or less, preferably about 100 nm or less, more preferably about 50 nm or less are used. The fiber length is about 500 μm or less, preferably about 1 to 100 μm.

熱硬化性樹脂およびCNTの有機溶媒中への分散処理は、CNTの凝集塊を小さくすることができるものであれば任意の分散処理機、例えばホモジナイザ、超音波ホモジナイザ、超音波洗浄器等を用いることができる。この工程でCNTの凝集塊が大きいと、得られる成形物にCNTの凝集塊が残り易いので、分散効率の高い分散装置が用いられる。このような分散処理機を用いての分散処理は一般に約1/4〜5時間程度行われる。この分散処理の際、ドデシルベンゼンスルホン酸ナトリウム、ラウリルエーテル硫酸ナトリウム、オレイン酸ナトリウム等のアニオン系界面活性剤、ポリオキシエチレンノニルフェノール、ソルビタンモノラウリン酸エステル等の非イオン系界面活性剤を、CNTに対して約10〜200重量％程度用いられることが好ましい。   For the dispersion treatment of the thermosetting resin and CNT in the organic solvent, any dispersion treatment machine such as a homogenizer, an ultrasonic homogenizer, an ultrasonic cleaner or the like can be used as long as the aggregate of CNT can be reduced. be able to. If the agglomerates of CNT are large in this step, the agglomerates of CNTs are likely to remain in the obtained molded product, so that a dispersion device with high dispersion efficiency is used. Generally, dispersion processing using such a dispersion processor is performed for about 1/4 to 5 hours. During this dispersion treatment, anionic surfactants such as sodium dodecylbenzenesulfonate, sodium lauryl ether sulfate, and sodium oleate, and nonionic surfactants such as polyoxyethylene nonylphenol and sorbitan monolaurate are applied to the CNTs. About 10 to 200% by weight is preferably used.

これらの分散処理液に添加、混合される黒鉛は、天然黒鉛、人造黒鉛のいずれでもよく、その平均粒径は約30〜200μm、好ましくは約50〜180μmの範囲のものが用いられる。これ以下の平均粒径のものを用いると、得られる成形品の電気特性が低下し、一方これ以上の平均粒径のものを用いると、成形品の外観が悪化する。混合のための攪拌処理には、攪拌翼、ミキサ、ブレンダ、ニーダ等の混合機が用いられる。CNTの充填量が増加すると、必要な有機溶媒量も増加するため、混合物の状態も異ってくるので、CNTの充填量(混合物の状態)に応じて混合機を使い分ける必要がある。   The graphite added to and mixed with these dispersion treatment liquids may be either natural graphite or artificial graphite, and the average particle diameter thereof is about 30 to 200 μm, preferably about 50 to 180 μm. If the average particle size is less than this, the electrical properties of the resulting molded product are lowered, while if the average particle size is larger than this, the appearance of the molded product is deteriorated. A mixer such as a stirring blade, a mixer, a blender, or a kneader is used for the stirring process for mixing. As the amount of CNT filling increases, the amount of organic solvent required also increases, so the state of the mixture also changes. Therefore, it is necessary to use different mixers according to the amount of CNT filling (the state of the mixture).

これらの各混合成分は、燃料電池用セパレータ成形材料として用いる場合には、一般には熱硬化性樹脂が約5〜25重量％、好ましくは約10〜20重量％、黒鉛が約70〜90重量％、好ましくは約75〜85重量％、またCNTが約1〜8重量％、好ましくは約1〜6重量％の割合でそれぞれ用いられる。熱硬化性樹脂と黒鉛とは、燃料電池用セパレータ用途に用いられる一般的な使用割合であり、CNTの使用割合は、前述の如く導電性、流動性、コスト等の観点から、一般にこのような範囲とされる。これらの各必須成分以外にも、成形時の離型性改善という目的でステアリン酸、ステアリン酸亜鉛等の離型剤を、これらの各成分合計量に対して約0.1〜2重量％程度添加して用いることが好ましい。   When each of these mixed components is used as a separator molding material for a fuel cell, generally, the thermosetting resin is about 5 to 25% by weight, preferably about 10 to 20% by weight, and graphite is about 70 to 90% by weight. , Preferably about 75 to 85% by weight, and CNT is used in a proportion of about 1 to 8% by weight, preferably about 1 to 6% by weight. Thermosetting resin and graphite are general usage ratios used for separators for fuel cells, and the usage ratio of CNTs is generally such as described above from the viewpoint of conductivity, fluidity, cost, etc. Scope. In addition to each of these essential components, a release agent such as stearic acid and zinc stearate is added in an amount of about 0.1 to 2% by weight with respect to the total amount of each of these components for the purpose of improving mold release during molding. Are preferably used.

分散処理液に黒鉛を加え、攪拌処理した後、有機溶媒は乾燥除去される。この際、樹脂成分を硬化させると成形材料の流動性が低下するため、一般には約100℃以下、好ましくは80℃以下の温度で、必要に応じて減圧下での乾燥が行われる。乾燥は、混合物の不均一性を少くするために、攪拌機、ミキサ、ブレンダ、ニーダ等で攪拌を行いながら乾燥させることが好ましい。   After adding graphite to the dispersion treatment liquid and stirring, the organic solvent is removed by drying. At this time, since the fluidity of the molding material is lowered when the resin component is cured, drying is generally performed at a temperature of about 100 ° C. or lower, preferably 80 ° C. or lower, under reduced pressure as necessary. The drying is preferably performed while stirring with a stirrer, mixer, blender, kneader or the like in order to reduce the non-uniformity of the mixture.

有機溶媒を乾燥除去して得られた混合物は、混練した後粉砕処理される。混練の際せん断力を高くすると、CNTの破断が生じ、得られる成形物の電気特性が低下するようになる。通常の混練装置、例えばミル、ニーダ、加圧ニーダ、二軸押出機、オープンロール等の混練装置は、混練条件下でせん断力を変化させることが可能であり、必要とされるCNTの破断を生じさせない低せん断力での混練を可能とする。混練は、約80〜120℃で約1〜20分間程度行われる。その後、粉砕機による粉砕処理が行われるが、粉砕原料は平均粒径が1mm以下であることが好ましく、平均粒径がこれ以上大きいと、粒塊が残り易く、得られる成形品の外観が悪化する。   The mixture obtained by drying and removing the organic solvent is kneaded and then pulverized. When the shearing force is increased during kneading, the CNTs break, and the electrical properties of the obtained molded product are lowered. Ordinary kneading devices such as mills, kneaders, pressure kneaders, twin screw extruders, open rolls, etc., can change the shearing force under kneading conditions and break the required CNT. It enables kneading with a low shear force that does not occur. The kneading is performed at about 80 to 120 ° C. for about 1 to 20 minutes. Thereafter, a pulverization process is performed by a pulverizer, but the pulverized raw material preferably has an average particle size of 1 mm or less. To do.

このようにして得られた粉末状の成形材料は、固体電解質型燃料電池のセパレータ成形材料として好適に用いられる。この成形材料を用いてのセパレータへの成形は、約150〜250℃の成形温度、約1分間以上、好ましくは約2分間以上の成形時間、約10〜100MPa程度の成形圧力で、離型時に変形を生じないような成形条件下で行われる。また、アフターキュア等の方法により、完全に硬化させてもよい。   The powdery molding material thus obtained is suitably used as a separator molding material for solid oxide fuel cells. Molding to the separator using this molding material is performed at the time of mold release at a molding temperature of about 150 to 250 ° C., a molding time of about 1 minute or more, preferably a molding time of about 2 minutes or more, a molding pressure of about 10 to 100 MPa. It is carried out under molding conditions that do not cause deformation. Further, it may be completely cured by a method such as after cure.

次に、実施例について本発明を説明する。   Next, the present invention will be described with reference to examples.

実施例１
レゾール型フェノール樹脂(昭和高分子製品BRS-371；樹脂成分約65重量％のメタノール溶液)21.5重量部(樹脂分として15重量部)、気相成長法MWCNT(日機装製品;繊維径10〜30nm、平均繊維長1〜100μm)1重量部、ドデシルベンゼンスルホン酸ナトリウム界面活性剤1重量部およびメタノール70重量部(樹脂溶液分と合せた総メタノール量は77.5重量部)を、ホモジナイザで30分間分散処理し、得られた分散液に黒鉛(平均粒径160μm)84重量部および離型剤としてのステアリン酸1重量部を加え、ミキサで5分間攪拌した後、40℃の恒温槽で1時間の乾燥を行った。得られた混合物を、東洋精機製ラボプラストミルを用い、100℃で2分間の混練を行った後、パワーミルで粉砕して成形材料を得た。 Example 1
Resol type phenol resin (Showa polymer product BRS-371; methanol component of resin component about 65% by weight) 21.5 parts by weight (15 parts by weight as resin content), vapor phase growth method MWCNT (Nikkiso product; fiber diameter 10-30 nm, 1 part by weight (average fiber length of 1 to 100 μm), 1 part by weight of sodium dodecylbenzenesulfonate surfactant and 70 parts by weight of methanol (total amount of methanol combined with resin solution is 77.5 parts by weight) are dispersed with a homogenizer for 30 minutes Then, 84 parts by weight of graphite (average particle size 160 μm) and 1 part by weight of stearic acid as a release agent were added to the obtained dispersion, stirred for 5 minutes with a mixer, and then dried in a constant temperature bath at 40 ° C. for 1 hour. Went. The obtained mixture was kneaded at 100 ° C. for 2 minutes using a Laboplast mill manufactured by Toyo Seiki, and then pulverized with a power mill to obtain a molding material.

この成形材料を用い、180℃、5MPa、2分間の条件下で成形を行い、100×100×1.2mmの大きさの試験片を得た。この試験片について、接触抵抗(厚みの異なる試験片を作製し、抵抗測定用として10×10mmに加工し、この試料を金メッキ電極に挟み、荷重2MPa、電流1Aでの電圧を測定し、接触抵抗を算出)を測定した。これは、材料特性をセパレータ形状で測定すると、接触部の凹凸形状により測定誤差を生ずる場合があるため、接触抵抗の測定にはこの試験片が用いられた。なお、100×100×2mmの大きさの凹凸状溝流路付きセパレータを上記成形条件下で成形すると、所望の形状を有するセパレータが得られた。また、成形材料1gを用いて10mm径のタブレットを作製し、180℃で50トンの荷重をかけ、成形後の試料面積(流動面積)を測定して、流動性の目安とした。   Using this molding material, molding was performed under the conditions of 180 ° C., 5 MPa, 2 minutes to obtain a test piece having a size of 100 × 100 × 1.2 mm. About this test piece, contact resistance (preparing test pieces with different thicknesses, processing to 10 x 10 mm for resistance measurement, sandwiching this sample between gold-plated electrodes, measuring the voltage at a load of 2 MPa, current of 1 A, contact resistance Was calculated). This is because, when the material characteristics are measured in the shape of a separator, a measurement error may occur due to the uneven shape of the contact portion, so this test piece was used for measuring the contact resistance. In addition, when a separator with an uneven groove channel having a size of 100 × 100 × 2 mm was molded under the above molding conditions, a separator having a desired shape was obtained. Also, a 10 mm diameter tablet was prepared using 1 g of the molding material, a load of 50 tons was applied at 180 ° C., and the sample area (flow area) after molding was measured as a measure of fluidity.

実施例２
実施例1において、黒鉛量を82重量部、CNT量を3重量部に、また乾燥条件を50℃、3時間にそれぞれ変更した。 Example 2
In Example 1, the amount of graphite was changed to 82 parts by weight, the amount of CNTs was changed to 3 parts by weight, and the drying conditions were changed to 50 ° C. and 3 hours, respectively.

実施例３
実施例1において、黒鉛量を80重量部、CNT量を5重量部に、また乾燥条件を50℃、4時間にそれぞれ変更した。 Example 3
In Example 1, the amount of graphite was changed to 80 parts by weight, the amount of CNTs was changed to 5 parts by weight, and the drying conditions were changed to 50 ° C. and 4 hours, respectively.

実施例４
実施例1において、黒鉛量を79重量部、レゾール型フェノール樹脂量を20重量部(樹脂分)にそれぞれ変更した。 Example 4
In Example 1, the amount of graphite was changed to 79 parts by weight, and the amount of resol type phenol resin was changed to 20 parts by weight (resin content).

実施例５
実施例1において、黒鉛量を75重量部、CNT量を5重量部、レゾール型フェノール樹脂量を20重量部(樹脂分)に、また乾燥条件を50℃、4時間にそれぞれ変更した。 Example 5
In Example 1, the amount of graphite was changed to 75 parts by weight, the amount of CNTs was changed to 5 parts by weight, the amount of resol type phenol resin was changed to 20 parts by weight (resin content), and the drying conditions were changed to 50 ° C. and 4 hours, respectively.

比較例１
実施例1において、黒鉛量を85重量部に変更し、CNTが用いられず、恒温槽での乾燥が行われなかった。 Comparative Example 1
In Example 1, the amount of graphite was changed to 85 parts by weight, CNT was not used, and drying in a thermostatic bath was not performed.

比較例２
実施例1において、黒鉛量を75重量部、CNT量を10重量部に、また乾燥条件を50℃、10時間にそれぞれ変更した。 Comparative Example 2
In Example 1, the graphite amount was changed to 75 parts by weight, the CNT amount was changed to 10 parts by weight, and the drying conditions were changed to 50 ° C. and 10 hours, respectively.

比較例３
実施例1において、黒鉛量を80重量部、レゾール型フェノール樹脂量を20重量部(樹脂分)にそれぞれ変更し、CNTが用いられず、恒温槽での乾燥が行われなかった。 Comparative Example 3
In Example 1, the amount of graphite was changed to 80 parts by weight and the amount of resol-type phenol resin was changed to 20 parts by weight (resin content), CNTs were not used, and drying in a thermostatic bath was not performed.

以上の各実施例および比較例での測定結果は、成形材料の組成と共に、次の表に示される。比較例2は、成形ができないため、接触抵抗は測定不能であった。
表
実施例 比較例
1 2 3 4 5 1 2 3
〔成形材料組成〕
フェノール樹脂(重量部) 15 15 15 20 20 15 15 20
黒鉛 ( 〃 ) 84 82 80 79 75 85 75 80
CNT ( 〃 ) 1 3 5 1 5 − 10 −
離型剤 ( 〃 ) 1 1 1 1 1 1 1 1
〔測定項目〕
接触抵抗 (mΩ・cm2) 3.5 2.0 0.9 3.5 1.1 4.0 − 4.4
流動面積 (cm2) 42 41 38 48 48 39 29 46

The measurement results in the above examples and comparative examples are shown in the following table together with the composition of the molding material. Since Comparative Example 2 could not be molded, the contact resistance could not be measured.
table
Example Comparative Example
1 2 3 4 5 1 2 3
[Molding material composition]
Phenolic resin (parts by weight) 15 15 15 20 20 15 15 20
Graphite (〃) 84 82 80 79 75 85 75 80
CNT (〃) 1 3 5 1 5 − 10 −
Mold release agent (〃) 1 1 1 1 1 1 1 1
〔Measurement item〕
Contact resistance (mΩ ・ cm 2 ) 3.5 2.0 0.9 3.5 1.1 4.0 − 4.4
Flow area (cm 2 ) 42 41 38 48 48 39 29 46

Claims (6)

カーボンナノチューブを1〜8重量％含有する、黒鉛、熱硬化性樹脂およびカーボンナノチューブの均一混合物よりなる燃料電池用セパレータ成形材料。   A separator molding material for a fuel cell comprising a uniform mixture of graphite, a thermosetting resin and carbon nanotubes, containing 1 to 8% by weight of carbon nanotubes. 平均繊維径が500nm以下、繊維長が500μm以下のカーボンナノチューブが用いられた請求項１記載の燃料電池用セパレータ成形材料。   The fuel cell separator molding material according to claim 1, wherein carbon nanotubes having an average fiber diameter of 500 nm or less and a fiber length of 500 µm or less are used. 粒径30〜200μmの黒鉛が用いられた請求項１記載の燃料電池用セパレータ成形材料。   The separator molding material for fuel cells according to claim 1, wherein graphite having a particle size of 30 to 200 µm is used. 黒鉛70〜90重量％、熱硬化性樹脂5〜25重量％およびカーボンナノチューブ1〜8重量％の均一混合物よりなる請求項１記載の燃料電池用セパレータ成形材料。   The fuel cell separator molding material according to claim 1, comprising a homogeneous mixture of 70 to 90% by weight of graphite, 5 to 25% by weight of thermosetting resin, and 1 to 8% by weight of carbon nanotubes. 熱硬化性樹脂、それの可溶性有機溶媒およびカーボンナノチューブの分散処理液に黒鉛を加え、攪拌処理した後有機溶媒を乾燥除去し、得られた混合物を混練した後粉砕処理した均一混合物よりなる請求項１記載の燃料電池用セパレータ成形材料。   A method comprising: adding a graphite to a dispersion treatment solution of a thermosetting resin, a soluble organic solvent thereof and a carbon nanotube, stirring and then drying and removing the organic solvent; kneading the resulting mixture; The fuel cell separator molding material according to 1. 請求項１または５記載の成形材料から成形された固体高分子型燃料電池用セパレータ。
A separator for a polymer electrolyte fuel cell molded from the molding material according to claim 1 or 5.
JP2004034460A 2004-02-12 2004-02-12 Separator formation material for fuel cell Pending JP2005228538A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004034460A JP2005228538A (en) 2004-02-12 2004-02-12 Separator formation material for fuel cell

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004034460A JP2005228538A (en) 2004-02-12 2004-02-12 Separator formation material for fuel cell

Publications (1)

Publication Number Publication Date
JP2005228538A true JP2005228538A (en) 2005-08-25

Family

ID=35003077

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004034460A Pending JP2005228538A (en) 2004-02-12 2004-02-12 Separator formation material for fuel cell

Country Status (1)

Country Link
JP (1) JP2005228538A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180093395A (en) * 2017-02-13 2018-08-22 (주)엘지하우시스 Separator for fuel cell and method for manufacturing the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20180093395A (en) * 2017-02-13 2018-08-22 (주)엘지하우시스 Separator for fuel cell and method for manufacturing the same
KR102592974B1 (en) * 2017-02-13 2023-10-20 (주)엘엑스하우시스 Separator for fuel cell and method for manufacturing the same

Similar Documents

Publication Publication Date Title
Radzuan et al. The effect of milled carbon fibre filler on electrical conductivity in highly conductive polymer composites
Menzer et al. Percolation behaviour of multiwalled carbon nanotubes of altered length and primary agglomerate morphology in melt mixed isotactic polypropylene-based composites
Tang et al. Fracture toughness and electrical conductivity of epoxy composites filled with carbon nanotubes and spherical particles
Hollertz et al. Improvement of toughness and electrical properties of epoxy composites with carbon nanotubes prepared by industrially relevant processes
Lin et al. Melt mixing of polycarbonate with multi‐walled carbon nanotubes in miniature mixers
KR101700355B1 (en) Preparation method of carbon nanotube and dispersed composition of carbon nanotube
Lee et al. Structural optimization of graphite for high-performance fluorinated ethylene–propylene composites as bipolar plates
Liu et al. Electrical conductivity of carbon nanotube/poly (vinylidene fluoride) composites prepared by high-speed mechanical mixing
Sulong et al. Rheological and mechanical properties of carbon nanotube/Graphite/SS316L/polypropylene nanocomposite for a conductive polymer composite
Hassanabadi et al. Effect of particle size and shape on the reinforcing efficiency of nanoparticles in polymer nanocomposites
Cui et al. Facile fabrication of highly conductive polystyrene/nanocarbon composites with robust interconnected network via electrostatic attraction strategy
JP4363206B2 (en) Dispersing method of carbon nanotube
Hsiao et al. Effect of graphite sizes and carbon nanotubes content on flowability of bulk-molding compound and formability of the composite bipolar plate for fuel cell
JP2012210796A (en) Method of mixing fibrous nanomaterial with resin particle powder
Zambrzycki et al. Conductive hybrid polymer composites based on recycled carbon fibres and carbon nanofillers
He et al. A graphene oxide–polyvinylidene fluoride mixture as a precursor for fabricating thermally reduced graphene oxide–polyvinylidene fluoride composites
Zhu et al. Cellulose nanocrystal‐mediated assembly of graphene oxide in natural rubber nanocomposites with high electrical conductivity
Onyu et al. Evaluation of the possibility for using polypropylene/graphene composite as bipolar plate material instead of polypropylene/graphite composite
Chakraborty et al. Influence of different carbon nanotubes on the electrical and mechanical properties of melt mixed poly (ether sulfone)-multi walled carbon nanotube composites
JP2005228538A (en) Separator formation material for fuel cell
US11149121B2 (en) Method for producing composite resin particles, resin molded article, and composite resin particles
Peng et al. Electrostatic‐Assembly of Carbon Nanotubes (CNTs) and Polymer Particles in Water: a Facile Approach to Improve the Dispersion of CNTs in Thermoplastics
CN105742578B (en) A kind of nickel-hydrogen battery negative pole slurry preparation method of addition carbon nanotube
Vryonis et al. Solvent mixing and its effect on epoxy resin filled with graphene oxide
Dweiri et al. Optimization of electrical conductivity for composite bipolar plates in PEM fuel cell

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20070109

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20090917

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20090924

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20100209