METHOD FOR PRODUCING AROMATIC POLYIMIDE RESIN MOLDED PRODUCT

PROBLEM TO BE SOLVED: To provide a method for producing an aromatic polyimide resin molded product improved in mechanical properties, especially, tensile strength.SOLUTION: There is provided a method for producing an aromatic polyimide resin molded product, which is a reaction product between a pyromellitic dianhydride and a 4,4'-diaminodiphenyl ether, the method comprising the following two steps using a polyimide powder having an average particle diameter of 0.1 to 9 μm and an imide ring closure ratio of 50 to 95% and a specific surface area of 13 to 30 m/g: (1) a first step of producing a green compact by a first stage in which a polyimide powder is subjected to pressurizing and heating treatment by applying a pressure of 29 to 147 MPa at 185 to 250°C to hold 25 minutes or more per a molding thickness of 10 mm and a second stage in which the polyimide powder is subjected to pressurizing and heating treatment by applying a pressure of 29 to 147 MPa at 200 to 450°C to hold 40 minutes or more and (2) a second step of heating the green compact obtained in the first step at 350 to 500°C under a vacuum condition or in an inert gas atmosphere.SELECTED DRAWING: None 【課題】機械特性、特に引張強度が向上した芳香族ポリイミド樹脂成形品の製造方法を安定して提供すること。【解決手段】上記課題を解決するために本発明は次のとおりの構成を有する。ピロメリット酸二無水物と４，４'−ジアミノジフェニルエーテルとを反応物である芳香族ポリイミド樹脂成形品の製造方法であって、平均粒子径が０．１〜９μｍかつイミド閉環率が５０〜９５％かつ比表面積が１３〜３０ｍ２／ｇであるポリイミド粉末を用いて 、以下の２工程を含む、芳香族ポリイミド樹脂成形品の製造方法。（１）ポリイミド粉末に、１８５℃〜２５０℃で、２９〜１４７ＭＰａの圧力をかけて成形厚み１０ｍｍあたり２５ｍｉｎ以上保持し、加圧加熱処理する第１段階、次に２００℃〜４５０℃で、２９〜１４７ＭＰａの圧力をかけて４０ｍｉｎ以上保持し、加圧加熱処理する第２段階を行って、圧粉体を製造する第１工程、（２）第１工程で得られた圧粉体に、真空の条件、または不活性ガス雰囲気中で３５０〜５００℃で加熱を行う第２工程。【選択図】なし