JP3561407B2 - Method for manufacturing carbon honeycomb structure - Google Patents
Method for manufacturing carbon honeycomb structure Download PDFInfo
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- JP3561407B2 JP3561407B2 JP06236798A JP6236798A JP3561407B2 JP 3561407 B2 JP3561407 B2 JP 3561407B2 JP 06236798 A JP06236798 A JP 06236798A JP 6236798 A JP6236798 A JP 6236798A JP 3561407 B2 JP3561407 B2 JP 3561407B2
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- Prior art keywords
- carbon fiber
- polyamide
- honeycomb structure
- prepolymer
- fiber base
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Description
【０００１】
【産業上の利用分野】
本発明は、カーボンハニカム構造体の製造法に関する。
【０００２】
【従来の技術】
ハニカム構造体は、中空柱状のセルの平面的集合体よりなり、耐熱性のハニカム構造体は、航空機用のエンジン周り等、高温部位のサンドイッチパネル、航空機・宇宙機器等の圧力加熱を受ける構造部材、その他において用いられ、２６０℃程度の環境・常用温度において経時的な耐熱強度を有するものである。従来、軽量で高い機械的強度を有する重量比強度に優れたハニカム構造体の基材としては、アルミニウム箔、クラフト紙等が使用されているが、耐熱性を有するものとしては、ステンレス、チタン等の金属箔をハニカム状とし、ロウ付け加工を施したもの、ガラス繊維、炭素繊維等を基材とし、これにレゾールフェノール樹脂等の耐熱性樹脂を付着せしめたもの（繊維強化樹脂ハニカム構造体）、耐熱性芳香族ポリアミド合成紙を基材とし、これにレゾールフェノール樹脂等の耐熱性樹脂を付着せしめたもの、等が開発されている。
【０００３】
このうち繊維強化樹脂ハニカム構造体は、比強度、比剛性に優れているため、従来、航空機部品として使用されてきている。これをさらに航空機エンジン用部品として使用する場合は、高温度域（１２０〜１５０℃）での機械的強度に優れ、且つ２次及び３次曲面への加熱成形性に優れていることが要求される。従来は高温度域での機械的強度と、加熱成形性という２つの要求を満足させるために、２５０℃以上のガラス転移点を有し（従って、２５０℃以上で樹脂が柔らかくなり容易に成形ができる）、且つガラス転移点より１００℃低い温度では、加熱による機械的性能の劣化がないという特性を持つ熱可塑性樹脂が使用されてきた。しかし、この熱可塑性樹脂は通常は固体であり、適当な溶媒がないため、これを使用してハニカム構造体を製造する際には、樹脂を３５０℃以上の温度まで加熱して液状にすることが必要となる。このため、特殊な製造設備が必要となり、効率も悪く、コスト高となる。また、熱可塑性樹脂そのものも高価である。
【０００４】
【発明が解決しようとする課題】
従って、本発明の目的は、高温度域（１２０〜１５０℃）での機械的強度に優れ、且つ曲面への加熱成形性に優れたハニカム構造体を、安価に製造する方法を提供することである。
【０００５】
【課題を解決するための手段】
本発明は、ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布をコルゲート成形し、成形と同時又は成形後、架橋硬化させた波板シートと、ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布からなる平板シートとを、接着剤を介して交互に多数枚積層し、加圧加熱して樹脂を架橋硬化させて積層体を形成し、この積層体にポリアミドイミド樹脂プレポリマーを含浸し、架橋硬化させることを特徴とするカーボンハニカム構造体の製造法である。
【０００６】
【発明の実施の形態】
以下、本発明を詳細に説明する。
本発明において使用される炭素繊維基布は、例えば、ポリアクリロニトリル系炭素繊維で造られた織布、編布、不織布等であり、例えば、１Ｋ〜１２Ｋ （５０ ｇ／ｍ２〜６００ｇ／ｍ２）、好ましくは３Ｋ、２００ｇ／ｍ２ 平織の炭素繊維織布が挙げられる。厚みは通常、 ０．１〜０．５ ｍｍ程度、幅は ２５０〜３５０ ｍｍ程度が適当である。
この炭素繊維基布にポリアミドイミド樹脂プレポリマーを含浸する。含浸量は固形分で２０〜８０重量％、好ましくは５０重量％が適当である。ポリアミドイミド樹脂プレポリマーは、例えば、下記式（１） で表されるものが好ましい。
【０００７】
【化２】
式中、ｎは１０〜１００の数である。
【０００９】
式（１） のポリアミドイミド樹脂プレポリマーは、加熱により硬化して下記の式（２） で表される構造を有するポリアミドイミド樹脂になる。
【００１０】
【化３】
式（１） のポリアミドイミド樹脂プレポリマーは、旭チバ社からローデフタールという商品名で市販されており容易に入手できる。また、Ｄｉｅ Ａｎｇｅｗａｎｄｔｅ Ｍａｋｒｏｍｏｌｅｋｕｌａｒｅ Ｃｈｅｍｉｅ ４０／４１ （１９７４） １３９−１５８記載の方法で容易に製造できる。
このポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布を、波形ロールを用いてコルゲート成形する。波形の波の高さ及び幅は２〜３ｍｍ、波のピッチは８〜９ｍｍが適当である。ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布（平板）を、０．１ 〜１０ｋｇｆ／ｃｍ２ 、好ましくは５．０ｋｇｆ／ｃｍ２の圧力をかけながら、樹脂の粘着性を利用して、コルゲートラックに張り付かせる。次いで同型のラックを、基布の上面にかぶせ、温度 １５０〜４５０ ℃、好ましくは ２５０〜３００ ℃、圧力 ０．１〜２０ｋｇｆ／ｃｍ２ 、好ましくは６．０ｋｇｆ／ｃｍ２で、 ０．５〜２４時間、好ましくは ６時間、加熱加圧して樹脂を架橋硬化させ、コルゲートシートを製造する。
このコルゲートシート（波板）に、同様のポリアミドイミド樹脂プレポリマーからなる接着剤を１０〜３００ｇ／ｍ２ 塗布し、ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布（平板）を重ね合わせ、波板と平板を接着剤を介して多数枚（例えば、それぞれ １５０〜４００ 枚程度）重ね合わせ、温度 １５０〜４５０ ℃、好ましくは ２５０℃、圧力 ０．１〜１０ｋｇｆ／ｃｍ２ 、好ましくは１．０ｋｇｆ／ｃｍ２で、 ０．５〜２４時間、好ましくは ６時間、加熱加圧してプレポリマー樹脂を架橋硬化させ、ハニカム構造体を得る。さらにこれに、ポリアミドイミド樹脂プレポリマーを含浸し、同様の条件で加熱加圧して架橋し、ハニカム構造体を補強してもよい。
ポリアミドイミド樹脂プレポリマーは、プレポリマーのみからなるものでもよいし、これを適当な溶媒、例えば、Ｎ−メチルピロリドン、ジメチルホルムアミド等に溶解し、固形分濃度５〜２５重量％にしたものを使用してもよい。特に、ポリアミドイミド樹脂プレポリマーを含浸して、ハニカム構造体を補強する場合には、プレポリマーの溶液を使用することが好ましい。この場合、プレポリマーの含浸・蒸発・硬化処理はプレポリマーの含浸量が固形分として１〜１００ｋｇ／ｍ３ 、望ましくは５０ｋｇ／ｍ３ 程度になるまで繰り返す。
そして、その後所望の厚み、例えば ０．３〜３ インチ（７．６ 〜３８ｍｍ）の厚みに裁断して、本発明のハニカム構造体を得る。
【発明の効果】
本発明ではポリアミドイミド樹脂プレポリマーを使用しているため、比較的低温で架橋させることができる。また、プレポリマー自体が優れた粘着力を持っているため、一般的なハニカム構造体の製造法であるラック＆ ギア法を利用して容易にハニカム構造体の製造ができる。
【実施例１】
幅１ｍ、長さ１００ｍの炭素繊維織布（平織３Ｋ、密度（打ち込み本数）縦横共４９２ 本／ｍ 、厚み０．２５ｍｍ）に式（１） で表されるポリアミドイミド樹脂プレポリマー（液状）を４０重量％となるように含浸した。このポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布を、波形ロールを用いてコルゲート成形した。波形の波の高さ及び幅は２．７ ｍｍ、波のピッチは８．３ ｍｍとした。ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布（平板）を、５．０ ｋｇｆ／ｃｍ２ の圧力をかけながら、樹脂の粘着性を利用して、コルゲートラックに張り付かせた。次いで同型のラックを、基布の上面にかぶせ、温度２５０ ℃、圧力６．０ ｋｇｆ／ｃｍ２ で、６時間、加熱加圧して樹脂を架橋硬化させ、コルゲートシートを製造した。
このコルゲートシート（波板）に、同様のポリアミドイミド樹脂プレポリマーからなる接着剤を５０ｇ／ｍ２塗布し、ポリアミドイミド樹脂プレポリマーを含浸した炭素繊維基布（平板）を重ね合わせ、波板と平板を接着剤を介して３００ 枚重ね合わせ、温度２５０ ℃、圧力１．０ ｋｇｆ／ｃｍ２ で、６時間、加熱加圧してプレポリマー樹脂を架橋硬化させ、ハニカム構造体を得た。
さらにこれに、ポリアミドイミド樹脂プレポリマーをＮ−メチルピロリドンに溶解した１０重量％溶液を含浸し、２０５ ℃で１時間加熱して溶媒を蒸発させ、同様の条件で加熱加圧して架橋し、ハニカム構造体を補強した。この含浸・蒸発・硬化処理を１０回繰り返し、プレポリマーの含浸量を固形分として５０ｋｇ／ｍ３ とした。これを厚み１２．７ｍｍに裁断し、本発明のハニカム構造体を得た。[0001]
[Industrial applications]
The present invention relates to a method for manufacturing a carbon honeycomb structure.
[0002]
[Prior art]
The honeycomb structure is a planar assembly of hollow columnar cells, and the heat-resistant honeycomb structure is a structural member that is subjected to pressure heating, such as a sandwich panel in a high-temperature portion, such as around an aircraft engine, or an aircraft or a space device. And has a heat resistance over time in an environment and a normal temperature of about 260 ° C. Conventionally, aluminum foil, kraft paper, and the like have been used as a base material for a honeycomb structure that is lightweight and has high mechanical strength and excellent weight-to-strength strength. A metal foil made of honeycomb, brazed, glass fiber, carbon fiber, etc. as base material, to which heat-resistant resin such as resol phenol resin is adhered (fiber reinforced resin honeycomb structure) A heat-resistant aromatic polyamide synthetic paper as a base material to which a heat-resistant resin such as a resol phenol resin is adhered has been developed.
[0003]
Among them, the fiber reinforced resin honeycomb structure has been used as an aircraft component because of its excellent specific strength and specific rigidity. When this is further used as an aircraft engine part, it is required to have excellent mechanical strength in a high temperature range (120 to 150 ° C.) and to have excellent heat moldability to secondary and tertiary curved surfaces. You. Conventionally, in order to satisfy the two requirements of mechanical strength in a high temperature range and heat moldability, it has a glass transition point of 250 ° C or more (therefore, the resin becomes soft at 250 ° C or more and molding is easy. At a temperature 100 ° C. lower than the glass transition point, a thermoplastic resin has been used which has the property of not deteriorating mechanical performance due to heating. However, since this thermoplastic resin is usually a solid and there is no suitable solvent, when manufacturing a honeycomb structure using the thermoplastic resin, it is necessary to heat the resin to a temperature of 350 ° C. or more to make it liquid. Is required. For this reason, special manufacturing equipment is required, the efficiency is low, and the cost is high. Also, the thermoplastic resin itself is expensive.
[0004]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a method for inexpensively manufacturing a honeycomb structure excellent in mechanical strength in a high temperature range (120 to 150 ° C.) and excellent in heat moldability to a curved surface. is there.
[0005]
[Means for Solving the Problems]
The present invention is to corrugate a carbon fiber base fabric impregnated with a polyamide-imide resin prepolymer, and simultaneously or after molding, a cross-linked and cured corrugated sheet, and a carbon fiber base fabric impregnated with a polyamide-imide resin prepolymer. A large number of flat sheets are alternately laminated with an adhesive, and the resin is cross-linked and cured by applying pressure and heat to form a laminated body. The laminated body is impregnated with a polyamideimide resin prepolymer, and then cross-linked and cured. A method for manufacturing a carbon honeycomb structure.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
Carbon-fiber cloth used in the present invention include, for example, woven fabric made with polyacrylonitrile-based carbon fibers, knitted fabrics, a nonwoven fabric or the like, for example, 1K~12K (50 g / m 2 ~600g / m 2 ), Preferably 3K, 200 g / m 2 plain weave carbon fiber woven fabric. It is appropriate that the thickness is usually about 0.1 to 0.5 mm and the width is about 250 to 350 mm.
This carbon fiber base fabric is impregnated with a polyamideimide resin prepolymer. The amount of impregnation is suitably 20 to 80% by weight, preferably 50% by weight in solid content. The polyamideimide resin prepolymer is preferably, for example, one represented by the following formula (1).
[0007]
Embedded image
In the formula, n is a number of 10 to 100.
[0009]
The polyamide-imide resin prepolymer of the formula (1) is cured by heating to become a polyamide-imide resin having a structure represented by the following formula (2).
[0010]
Embedded image
The polyamide-imide resin prepolymer of the formula (1) is commercially available from Asahi Ciba under the trade name Rohdephthal and can be easily obtained. Further, it can be easily produced by the method described in Die Angewandte Makromolekulare Chemie 40/41 (1974) 139-158.
The carbon fiber base fabric impregnated with the polyamide-imide resin prepolymer is corrugated using a corrugated roll. The height and width of the corrugated wave are preferably 2-3 mm, and the pitch of the wave is suitably 8-9 mm. The carbon-fiber cloth impregnated with a polyamide imide resin prepolymer (flat), 0.1 ~10kgf / cm 2, preferably while applying a pressure of 5.0 kgf / cm 2, using the adhesion of the resin, corrugated Stick it to the rack. Next, a rack of the same type is placed on the upper surface of the base cloth, and the temperature is 150 to 450 ° C., preferably 250 to 300 ° C., the pressure is 0.1 to 20 kgf / cm 2 , preferably 6.0 kgf / cm 2 , and 0.5 to 0.5 kgf / cm 2 . The resin is crosslinked and cured by applying heat and pressure for 24 hours, preferably 6 hours, to produce a corrugated sheet.
An adhesive made of the same polyamide-imide resin prepolymer is applied to the corrugated sheet (corrugated sheet) in an amount of 10 to 300 g / m 2 , and a carbon fiber base cloth (flat plate) impregnated with the polyamide-imide resin prepolymer is overlaid. A number of plates (for example, about 150 to 400 each) are superposed on each other via an adhesive, and the temperature is 150 to 450 ° C., preferably 250 ° C., and the pressure is 0.1 to 10 kgf / cm 2 , preferably 1.0 kgf. / Cm 2 for 0.5 to 24 hours, preferably 6 hours to crosslink and cure the prepolymer resin to obtain a honeycomb structure. Further, the honeycomb structure may be impregnated with a polyamide-imide resin prepolymer and crosslinked by heating and pressing under the same conditions to reinforce the honeycomb structure.
The polyamide-imide resin prepolymer may be composed of only the prepolymer, or a solution prepared by dissolving the prepolymer in an appropriate solvent, for example, N-methylpyrrolidone, dimethylformamide, etc. to a solid concentration of 5 to 25% by weight. May be. In particular, when the honeycomb structure is reinforced by impregnation with a polyamideimide resin prepolymer, it is preferable to use a solution of the prepolymer. In this case, the impregnation and evaporation and curing processes of the prepolymer 1 to 100 kg / m 3 impregnation amount of prepolymer as solids, preferably repeated until about 50 kg / m 3.
Then, the honeycomb structure is cut into a desired thickness, for example, 0.3 to 3 inches (7.6 to 38 mm) to obtain the honeycomb structure of the present invention.
【The invention's effect】
In the present invention, since a polyamideimide resin prepolymer is used, crosslinking can be performed at a relatively low temperature. In addition, since the prepolymer itself has excellent adhesive strength, the honeycomb structure can be easily manufactured by using a rack and gear method, which is a general method for manufacturing a honeycomb structure.
Embodiment 1
A polyamide-imide resin prepolymer (liquid) represented by the formula (1) is applied to a carbon fiber woven fabric (width: 1 m, length: 100 m) (plain weave: 3 K, density (number of shots): 492 / m2, thickness: 0.25 mm). It was impregnated to 40% by weight. The carbon fiber base fabric impregnated with the polyamide-imide resin prepolymer was corrugated using a corrugated roll. The height and width of the wave of the waveform were 2.7 mm, and the pitch of the wave was 8.3 mm. A carbon fiber base fabric (flat plate) impregnated with a polyamide-imide resin prepolymer was adhered to a corrugated rack by utilizing the adhesiveness of the resin while applying a pressure of 5.0 kgf / cm 2 . Next, the same type of rack was covered on the upper surface of the base cloth, and heated and pressed at a temperature of 250 ° C. and a pressure of 6.0 kgf / cm 2 for 6 hours to crosslink and cure the resin, thereby producing a corrugated sheet.
To this corrugated sheet (corrugated sheet), an adhesive made of the same polyamide-imide resin prepolymer was applied at 50 g / m 2 , and a carbon fiber base cloth (flat sheet) impregnated with the polyamide-imide resin prepolymer was overlaid. 300 sheets were laminated with an adhesive and heated and pressed at a temperature of 250 ° C. and a pressure of 1.0 kgf / cm 2 for 6 hours to crosslink and harden the prepolymer resin to obtain a honeycomb structure.
Further, this was impregnated with a 10% by weight solution of a polyamideimide resin prepolymer dissolved in N-methylpyrrolidone, heated at 205 ° C. for 1 hour to evaporate the solvent, and cross-linked by heating and pressing under the same conditions. The structure was reinforced. This impregnation / evaporation / curing treatment was repeated 10 times, and the impregnation amount of the prepolymer was set to 50 kg / m 3 as a solid content. This was cut to a thickness of 12.7 mm to obtain a honeycomb structure of the present invention.
Claims (3)
該ポリアミドイミド樹脂プレポリマーが下記式 (1) で表される繰り返し単位を有する上記製造法。
The above production method, wherein the polyamide-imide resin prepolymer has a repeating unit represented by the following formula (1) .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06236798A JP3561407B2 (en) | 1998-03-13 | 1998-03-13 | Method for manufacturing carbon honeycomb structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06236798A JP3561407B2 (en) | 1998-03-13 | 1998-03-13 | Method for manufacturing carbon honeycomb structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH11254564A JPH11254564A (en) | 1999-09-21 |
| JP3561407B2 true JP3561407B2 (en) | 2004-09-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06236798A Expired - Fee Related JP3561407B2 (en) | 1998-03-13 | 1998-03-13 | Method for manufacturing carbon honeycomb structure |
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| Country | Link |
|---|---|
| JP (1) | JP3561407B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US9726275B2 (en) | 2014-12-18 | 2017-08-08 | Sl Corporation | Shift lever of automotive transmission |
| CN108840697B (en) * | 2018-06-29 | 2021-07-13 | 航天材料及工艺研究所 | Carbon/carbon composite material honeycomb and preparation method thereof |
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1998
- 1998-03-13 JP JP06236798A patent/JP3561407B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH11254564A (en) | 1999-09-21 |
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