JP3907549B2 - Varnish and cross-linked polyimide - Google Patents

Description

【００２４】
【化２２】

【００２５】
（ここで、Ｒ₁は水素原子、炭素数１〜１０の炭化水素基または芳香族基を表す。また式（１−ａ）において、ジカルボン酸またはそのエステル末端の反対側はどのような構造であってもよい）
Ｒ₁の具体例としては下記式（１９）に示される、
【００２６】
【化２３】

などが挙げられる。
【００２７】
３または４個のアミノ基を有する化合物としては、好ましい具体例としては、下記式（２）、（５）、（７）および（１２）で表される化合物が挙げられる。
【００２８】
【化２４】

（ここで、ｎは３または４を、Ｒ₂は下記式（３）で表される３または４価の基を表す。）
【００２９】
【化２５】

（ここで、Ｒ₃は下記式（４）で表される２価の基を表す。）
【００３０】
【化２６】

【００３１】
【化２７】

（ここで、Ｒ₄は−ＮＨ₂または−Ｈであり、Ｒ₅は下記式（６）で表される２価の基を表す。）
【００３２】
【化２８】

【００３３】
【化２９】

（ここで、Ｒ₆は下記式（８）で表される１価の基を表し、Ｒ₇は下記式（９）で表される１価の基を表し、Ｒ₈は下記式（１０）で表される２価の基を表す）
【００３４】
【化３０】

（ここで、Ｒ₉は下記式（１１）で表される２価の基を表す。）
【００３５】
【化３１】

(ここで、Ｒ₉は下記式（１１）で表される２価の基を表す。）
【００３６】
【化３２】

【００３７】
【化３３】

【００３８】
【化３４】

（ここで、Ｒ₁₀はＮまたはＣＨで表される３価の基を表す。）
【００３９】
具体例としては、例えば、トリス（ｐ−アミノフェニル）アミン、トリス（３−アミノフェニル）ホスフィンオキサイド、、トリス（４−アミノフェニル）メタン、１，３，５−トリス（４−アミノフェノキシ）ベンゼン、１，３，５−トリス（３−アミノフェノキシ）ベンゼン、１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン、トリアミノピリミジン、メラミンおよび下記式（２０）〜（２７）に表される化合物等が挙げられる。
これらは単独で、または、二種類以上を組み合わせて使用することが出来る。
【００４０】
【化３５】

【００４１】
【化３６】

【００４２】
【化３７】

【００４３】
【化３８】

【００４４】
【化３９】

【００４５】
【化４０】

【００４６】
【化４１】

【００４７】
【化４２】

【００４８】
本発明において、３または４個のアミノ基を有する化合物の使用量は、用いるポリアミド酸のジカルボン酸またはそのエステル末端１モルに対し、好ましくは０．１〜０．６モル、更に好ましくは０．２〜０．４モルである。該化合物の使用量が多い場合、および、少ない場合には、得られるポリイミド中の架橋していない分子鎖が多く、耐熱性、耐薬品性の向上効果が小さくなる傾向にある。ここでいうジカルボン酸またはそのエステル末端１モルとは上記した式（１−ａ）または式（１−ｂ）で表わされる末端構造１モルを表す。
【００４９】
本発明において、分子末端がジカルボン酸またはそのエステルであるポリアミド酸の有する繰り返し単位に、特に制限はなく、従来公知のポリアミド酸の繰り返し単位から任意に選択できる。本発明のポリアミド酸は、好ましくは、下記式（１３）で表される繰り返し構造を有するものである。
【００５０】
【化４３】

（ここで、Ｘは２価の芳香族基を、より好ましくは、下記式（１４）から選ばれる２価の芳香族基を示す。）
【００５１】
【化４４】

（ここで、式（１４）の芳香環の水素原子の一部は、アミノ基やカルボニル基と反応性を有しない置換基で置換されていても良い。Ｒ₁₁はそれぞれ独立であり、下記式（１５）で表される２価の基を表す）
【００５２】
【化４５】

【００５３】
（また、Ｙは４価の芳香族基を、より好ましくは、下記式（１６）から選ばれる４価の芳香族基を示す。）
【００５４】
【化４６】

【００５５】
ここで本発明のポリアミド酸は、前述の繰り返し構造から選ばれる２種以上の繰り返し単位を有していてもよい。この場合、２種以上の繰り返し単位のモル分率、繰り返し数、順序の定序性、規則性に制限はない。
【００５６】
本発明の分子末端がジカルボン酸またはそのエステルであるポリアミド酸の分子量に特に制限はなく、ワニスの粘度、得られる架橋ポリイミドの物性等に合わせ、任意に設定することが出来るが、対数粘度で示した場合、０．２から２．０ｄｌ／ｇ（Ｎ，Ｎ−ジメチルアセトアミド中、濃度０．５ｇ／ｄｌ、３５℃で測定。）の範囲であることが好ましく、０．４から１．２ｄｌ／ｇの範囲であることが特に好ましい。対数粘度が０．２未満では、分子末端がジカルボン酸またはそのエステルであるポリアミド酸の強度が低く、ワニスを塗布、イミド化する際に塗膜が割れる恐れがある。また、２．０以上の場合には、得られるポリアミド酸の末端カルボン酸基および／またはそのエステル基が著しく少ないため、架橋による物性向上の効果が得られ難いことがある。本発明の分子末端がジカルボン酸またはそのエステルであるポリアミド酸は、一般的な酸無水物末端のポリアミド酸に水またはアルコールを添加し、その末端をジカルボン酸またはそのエステルにすることにより得ることができる。
【００５７】
用いる酸無水物末端のポリアミド酸は、テトラカルボン酸二無水物に対し、等量未満の芳香族ジアミンを用いて得ることが出来る。本発明で用いるポリアミド酸は、用いる芳香族ジアミンの量を調整することで、得られるポリアミド酸の末端基量、ワニスの粘度、得られる架橋ポリイミドの架橋密度（架橋点間距離）を制御することが出来る。
【００５８】
本発明で用いる酸無水物末端のポリアミド酸の合成においては、テトラカルボン酸二無水物１モルに対し、ジアミンを０．８〜０．９９モル用いることが好ましい。用いるジアミンが少ない場合には、得られるポリマーの強度が低く、ワニスを塗布、イミド化する際に塗膜が割れるためあまり好ましくない。また、多い場合には、得られるポリアミド酸の酸無水物末端が極端に少ないため、十分に架橋させることが出来ないことがある。なお、テトラカルボン酸二無水物１モルとジアミンαモルを用いた場合、得られるポリアミド酸の末端酸無水物量は（１−α）×２モルとなる。
【００５９】
また、用いる酸無水物末端のポリアミド酸の製造方法に特に制限はなく、従来公知の芳香族ジアミンと芳香族テトラカルボン酸二無水物より従来公知の方法で得ることが出来、原料装入の順序、反応の濃度、温度、時間には何ら制限はない。なお、通常、ポリアミド酸は、不活性ガス雰囲気下、非プロトン性極性溶媒中で、ジアミンとテトラカルボン酸二無水物を、常温〜６０℃程度で数時間反応させることにより得られる。本発明に用いる酸無水物末端のポリアミド酸は、溶剤中で合成し溶剤に溶解したままのものであっても、また、貧溶媒を用いて析出させ、固体状態としたものであっても良い。
【００６０】
ここで、用いることのできる従来公知の芳香族ジアミンとしては、例えばm-フェニレンジアミン、o-フェニレンジアミン、p-フェニレンジアミン、4,4'-ジアミノジフェニルエーテル、3,3'-ジアミノジフェニルエーテル、3,4'-ジアミノジフェニルエーテル、ビス(3-アミノフェニル)スルフィド、ビス(4-アミノフェニル)スルフィド、(3-アミノフェニル)(4-アミノフェニル)スルフィド、ビス(3-アミノフェニル)スルホキシド、ビス(4-アミノフェニル)スルホキシド、(3-アミノフェニル)(4-アミノフェニル)スルホキシド、ビス(3-アミノフェニル)スルホン、ビス(4-アミノフェニル)スルホン、(3-アミノフェニル)(4-アミノフェニル)スルホン、3,3'-ジアミノベンゾフェノン、4,4'-ジアミノベンゾフェノン、3,4'-ジアミノベンゾフェノン、1,3-ビス(3-アミノフェノキシ)ベンゼン、1,3-ビス(4-アミノフェノキシ)ベンゼン、1,3-ビス(4-アミノフェノキシ)ベンゼン、1,4-ビス(3-アミノフェノキシ)ベンゼン、1,4-ビス(4-アミノフェノキシ)ベンゼン、4,4'ービス(3-アミノフェノキシ)ビフェニル、4,4'ービス(4-アミノフェノキシ)ビフェニル、ビス[4-(3-アミノフェノキシ)フェニル]ケトン、ビス[4-(4-アミノフェノキシ)フェニル]ケトン、ビス[4-(3-アミノフェノキシ)フェニル]スルフィド、ビス[4-(4-アミノフェノキシ)フェニル]スルフィド、ビス[4-(3-アミノフェノキシ)フェニル]スルホキシド、ビス[4-(4-アミノフェノキシ)フェニル]スルホキシド、ビス[4-(3-アミノフェノキシ)フェニル]スルホン、ビス[4-(4-アミノフェノキシ)フェニル]スルホン、ビス[4-(3-アミノフェノキシ)フェニル]エーテル、ビス[4-(4-アミノフェノキシ)フェニル]エーテル、3,3'-ジアミノ-4,4'-ジフェノキシベンゾフェノン、4,4'-ジアミノ-5,5'-ジフェノキシベンゾフェノン、3,4'-ジアミノ-4,5'-ジフェノキシベンゾフェノン、3,3'-ジアミノ-4-フェノキシベンゾフェノン、4,4'-ジアミノ-5-フェノキシベンゾフェノン、3,4'-ジアミノ-4-フェノキシベンゾフェノン、3,4'-ジアミノ-5'-フェノキシベンゾフェノン、3,3'-ジアミノ-4,4'-ジビフェノキシベンゾフェノン、4,4'-ジアミノ-5,5'-ジビフェノキシベンゾフェノン、3,4'-ジアミノ-4,5'-ジビフェノキシベンゾフェノン、3,3'-ジアミノ-4-ビフェノキシベンゾフェノン、4,4'-ジアミノ-5-ビフェノキシベンゾフェノン、3,4'-ジアミノ-4-ビフェノキシベンゾフェノン、3,4'-ジアミノ-5'-ビフェノキシベンゾフェノン、2,2'-ビス(トリフルオロメチル)-4,4'-ジアミノビフェニル、2-トリフルオロメチル-4,4'-ジアミノジフェニルエーテル、2'-トリフルオロメチル-3,4'-ジアミノジフェニルエーテル、2,2-ビス(3-アミノフェニル)-1,1,1,3,3,3-ヘキサフルオロプロパン、2,2-ビス(4-アミノフェニル)-1,1,1,3,3,3-ヘキサフルオロプロパン、1,3-ビス(3-アミノフェノキシ)-4-トリフルオロメチルベンゼン、1,3-ビス(3-アミノフェノキシ)-5-トリフルオロメチルベンゼン、1,3-ビス(3-アミノ-5-トリフルオロメチルフェノキシ)ベンゼン、1,4-ビス(3-アミノ-5-トリフルオロメチルフェノキシ)ベンゼン、1,3-ビス(3-アミノ-5-トリフルオロメチルフェノキシ)-5-トリフルオロメチルベンゼン、1,3-ビス(3-アミノ-5-トリフルオロメチルフェノキシ)-4-トリフルオロメチルベンゼン、1,3-ビス(4-アミノ-2-トリフルオロメチルフェノキシ)ベンゼン、1,4-ビス(4-アミノ-2-トリフルオロメチルフェノキシ)ベンゼン、2,2-ビス[4-(3-アミノフェノキシ)フェニル]-1,1,1,3,3,3-ヘキサフルオロプロパン、2,2-ビス[4-(4-アミノフェノキシ)フェニル]-1,1,1,3,3,3-ヘキサフルオロプロパン等が挙げられ、これらは単独または2種以上を混合して使用することができる。
【００６１】
ここで、用いることのできる従来公知の芳香族テトラカルボン酸二無水物としては、例えばピロメリット酸二無水物、3,3',4,4'-ベンゾフェノンテトラカルボン酸二無水物、2,3',3,4'-ベンゾフェノンテトラカルボン酸二無水物、3,3',4,4'-ビフェニルテトラカルボン酸二無水物、2,3',3,4'-ビフェニルテトラカルボン酸二無水物、2,2',3,3'-ビフェニルテトラカルボン酸二無水物、ビス(3,4-ジカルボキシフェニル)エーテル二無水物 、ビス(3,4-ジカルボキシフェニル)スルホン二無水物、2,2-ビス(3,4-ジカルボキシフェニル)ー1,1,1,3,3,3-ヘキサフルオロプロパン二無水物等が挙げられ、これらは単独あるいは２種以上混合して使用することが出来る。
【００６２】
ここで、ポリアミド酸の合成に用いることの出来る反応溶媒に特に制限はなく、例えばＮ，Ｎ−ジメチルホルムアミド、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ，Ｎ−ジエチルアセトアミド、Ｎ−メチル−２−ピロリドン、１，３−ジメチル−２−イミダゾリジノン、Ｎ−メチルカプロラクタム、ヘキサメチルホスホロトリアミド、１，２−ジメトキシエタン、ビス（２−メトキシエチル）エーテル、１，２−ビス（２−メトキシエトキシ）エタン、テトラヒドロフラン、ビス［２−（２−メトキシエトキシ）エチル］エーテル、１，４−ジオキサン、ジメチルスルホキシド、ジメチルスルホン、ジフェニルエーテル、スルホラン、ジフェニルスルホン、テトラメチル尿素、アニソール等が挙げられる。これらの溶媒は、単独または２種以上混合して用いても差し支えない。
【００６３】
本発明のワニスは、３または４個のアミノ基を有する化合物、および、分子末端がジカルボン酸またはそのエステルであるポリアミド酸を含んでなり、前述のポリアミド酸の製造方法により得られる分子末端が酸無水物基であるポリアミド酸溶液に、水またはアルコールを添加して、末端酸無水物基をジカルボン酸またはそのエステルにした後、３または４個のアミノ基を有する化合物を溶解させることにより得ることが出来る。
【００６４】
また、前述の溶媒類に、分子末端がジカルボン酸またはそのエステルである固体状のポリアミド酸や、分子末端がジカルボン酸またはそのエステルであるポリアミド酸溶液と、３または４個のアミノ基を有する化合物を溶解して調製することが出来る。また、本発明のワニスは、３または４個のアミノ基を有する化合物および分子末端がジカルボン酸またはそのエステルであるポリアミド酸の濃度に特に制限はなく、ワニスの保存安定性や塗布性に応じ、任意に調製することが出来る。
【００６５】
なお、本発明のワニスは、３または４個のアミノ基を有する化合物および分子末端がジカルボン酸またはそのエステルであるポリアミド酸の他に、イミド化を促進する触媒、溶剤の除去性やワニスの粘度、保存安定性を変化させるための溶剤、基材との接着性を調整するカップリング材、得られる架橋ポリイミドの特性を変化させるフィラー類（例えば繊維強化剤、シリカ、アルミナ、マイカ、タルク、微粉金属類等）を含んでいても良い。
【００６６】
本発明の分子末端がジカルボン酸またはそのエステルであるポリアミド酸は、上記分子末端が酸無水物であるポリアミド酸に水またはアルコールを加えることにより、加水分解反応が進行し、得ることが出来る。この加水分解反応機構については、式（２８）のように予想される（反応式中、Ａはポリアミド酸主鎖部分、Ｒは水素または炭素数１から１０の炭化水素基または芳香族基を表す）。
【００６７】
【化４７】

【００６８】
まず、分子末端が酸無水物であるポリアミド酸に水またはアルコールを加えることにより、ポリアミド酸主鎖中のアミド結合が加水分解して主鎖が切断され、末端がアミノ基および酸無水物基のポリアミド酸と、末端がジカルボン酸またはそのエステルおよび酸無水物基のポリアミド酸の２種が生成する。次に生成したアミノ基末端と元々ある酸無水物末端がアミド化反応を生じ、その結果、分子末端がジカルボン酸またはそのエステルであるポリアミド酸が生成すると予想される。
【００６９】
本発明においては、末端ジカルボン酸無水物基１モルに対し、水および／またはアルコールを１〜２モル用いることが好ましい。用いる水および／またはアルコールが少ない場合には、加水分解反応が十分に進行しないため、ポリアミド酸末端にジカルボン酸無水物基が残存し、後に加える３または４個のアミノ基を有する化合物と容易に反応して架橋し、ゲル化してしまう可能性がある。また、多い場合には、必要以上にポリアミド酸主鎖中のアミド結合を加水分解することとなり、酸無水物末端とアミド化反応できない過剰のアミノ基末端が生成し、分子量の低下および耐熱性の低下を招く恐れがある。
【００７０】
ここで、分子末端がジカルボン酸またはそのエステルであるポリアミド酸を製造するため、酸無水物基末端のポリアミド酸を加水分解するために用いることの出来る化合物としては、例えば、水、メタノール、エタノール、１−プロパノール、２−プロパノール、１−ブタノール、２−ブタノール、２−メチル−１−プロパノール、２−メチル−２−プロパノール、１−ペンタノール、２−ペンタノール、３−ペンタノール、２−メチル−１−ブタノール、２−メチル−２−ブタノール、１−ヘキサノール、２−ヘキサノール、３−ヘキサノール、フェノール、クレゾールなどが挙げられる。これらの水および／またはアルコールは、単独または２種以上混合して用いても差し支えない。
【００７１】
本発明の架橋ポリイミドは、分子末端がジカルボン酸またはそのエステルであるポリアミド酸の末端基がイミド化時に脱水または脱アルコールして酸無水物末端となり、３または４個のアミノ基を有する化合物と反応して、アミド酸の生成とそのイミド化により生成する架橋ポリイミドである。本発明の架橋ポリイミドは、未架橋の直鎖状ポリイミドに比べ、高いガラス転移温度と、高い耐薬品性を示す。また、その架橋構造がイミド結合であるため、他の架橋方法により得られる架橋ポリイミドに比べ、高い分解温度を示す。さらに、本発明の架橋ポリイミドは、未架橋の直鎖状ポリイミドに比べ、高い機械強度や、摺動、摩耗、疲労特性を有することが期待される。
【００７２】
本発明の架橋ポリイミドは、本発明のワニスである分子末端がジカルボン酸またはそのエステルであるポリアミド酸のイミド化反応および３または４個のアミノ基を有する化合物とポリアミド末端との反応により得ることが出来る。本発明においてそのイミド化方法に特に限定はなく、従来公知の化学的あるいは熱的なイミド化方法を用いることが出来る。イミド化方法としては、例えば、基材上に塗布したワニスを熱風乾燥した後、基材より剥離し、さらに高温で熱処理する方法、基材に付いたまま高温で熱処理する方法、無水酢酸等の脱水剤に浸漬し化学的に脱水イミド化する方法などがあげられる。
【００７３】
本発明のワニスを熱イミド化し、架橋ポリイミドを製造する場合、そのイミド化条件は、通常のポリアミド酸の熱イミド化条件で十分であり、架橋のためのさらなる高温処理や、長時間のアニール処理は必要ない。熱イミド化時の温度に制限はないが、得られる樹脂や基材の酸化等による劣化を抑制するために、３００℃以下であることが特に好ましい。
【００７４】
本発明のワニスは、含有するポリアミド酸が架橋部位を有さない直鎖状であるため、通常のポリアミド酸ワニスと同様の取り扱い、すなわち、流延、キャスト等が出来、さらに、通常の熱処理によりイミド化と同時に架橋構造を形成するため、従来公知の直鎖状ポリイミドの製造条件により架橋ポリイミドを得ることが出来る。
【００７５】
本発明の架橋ポリイミドは、フィルム、電線や光ファイバーの被覆材、エレクトロニクス用コーティング材（層間絶縁膜やパッシベーション膜等）、金属箔等と積層した回路基板、磁気テープ用ベースフィルム、繊維強化複合材料用マトリックス樹脂、摺動部材などとして有用である。
【００７６】
【実施例】
以下、本発明を実施例により更に具体的に説明するが、本発明はこれら実施例に限定されない。
【００７７】
実施例中の各評価方法を以下に示す。
対数粘度（ηinh）：樹脂量０．５ｇに相当する量のポリアミド溶液をジメチルアセトアミドに溶解し、１００ミリリットルとした後、３５℃において、ウベローデ粘度計で測定した。
ガラス転移温度（Ｔｇ）：ＤＳＣ（示差走査型熱量計、島津製作所製・ＤＳＣ−６０）により、２５℃から４３０℃まで昇温速度１０℃／分で測定した。
５％重量減少温度（Ｔｄ5%）：ＴＧＡ（熱重量測定装置、島津製作所製・ＴＧＡ−５０）により空気中にて測定した。
【００７８】
光線透過率（Ｔ％）：ＵＶ（紫外可視吸光光度計、日本分光製・Ｖ−５５０）を用い、厚さ５０マイクロメートルのキャストフィルムの４２０ｎｍにおける光線透過率を測定した。
伸び：ＴＭＡ（熱機械分析装置、島津製作所製・ＴＭＡ−５０）を用い、短冊状フィルム（厚さ５０マイクロメートル、幅５．０mm、測定長１５．０ｍｍ）の引張伸び測定（加重３．０ｇ、昇温速度５℃／ｍｉｎ）を行った。
耐薬品性：ｐ−クロロフェノール９０重量％／フェノール１０重量％混合溶媒１００ミリリットルに、ポリイミドフィルム０．５ｇを装入し、１８０℃１０分間加熱撹拌して溶解の有無を目視で観察した。
【００７９】
合成例１
１，３，５−トリス（１−（４−アミノ−３−クロロフェニル)−１−メチルエチル）ベンゼンの合成
２００ｍｌの３口反応容器に活性白土１．９８ｇ、２−クロロアニリン１２７．５７ｇ(１．００mol)、１，３，５−トリイソプロペニルベンゼン２０．８７ｇ (純度９５質量％、０．１０mol)を仕込み、２１０℃で３時間撹拌した。混合物を１００℃に冷却し、活性白土をろ別した。ろ液を高速液体クロマトグラフィー（ＨＰＬＣ）で分析したところ、目的物の１，３，５−トリス（１−（４−アミノ−３−クロロフェニル)−１−メチルエチル）ベンゼンが８６．５％の反応収率で生成していた。過剰の２−クロロアニリンを減圧下留去した後、目的物を４２．８ｇ（純度９５質量％、７０mmol、単離収率７０%）得た。目的物の物性は以下の通り。
融点 108.0〜109.0 ℃
¹H-NMR (CDCl₃) δ:1.46 (s, 18H), 3.90 (s, 6H), 6.60 (d, 3H, J = 8.4 Hz), 6.75 (dd, 3H, J =8.4, 1.9 Hz), 6.84 (s, 3H), 7.01 (d, 3H, J = 1.9 Hz)
FD-mass 528(M+)
【００８０】
合成例２
１，３，５−トリス（１−（４−アミノフェニル)−１−メチルエチル）ベンゼンの合成
１００ｍｌの３口反応容器に窒素雰囲気下でアニリン３０ｍｌ、アニリン塩酸塩１０．３６ｇ（８０mmol）を加え１５０℃まで昇温した。反応溶液に撹拌しながら１，３，５−トリス（１−クロロ−１−メチルエチル）ベンゼン５．０ｇ(純度７５質量％、１２．２mmol)を１５０℃で加えた後、１８０℃で５時間撹拌した。反応溶液を１５０℃まで冷却し、ヘキサン２００ｍｌと酢酸エチル４００ｍｌの混合溶媒中に添加し、結晶を析出させた。１５℃まで冷却した後、結晶をろ別した。得られた結晶を水２００ｍｌ中でリスラリーすることによりアニリン塩酸塩を除去した。結晶をろ別後、酢酸エチル５０ｍｌと水５０ｍｌの混合溶液に分散させ、１０％水酸化ナトリウム水溶液を用いて中和した。有機相を分離後、溶媒を濃縮した。ヘキサンを用いて再結晶を行い、目的物の１，３，５−トリス（１−（４−アミノフェニル)−１−メチルエチル）ベンゼンを３．８８ｇ（純度９８質量％、 ８．１mmol、単離収率６６％）得た。目的物の物性は以下の通り。
融点 143.3〜143.8 ℃
¹H-NMR (CDCl₃) δ:1.52 (s, 18H), 3.53 (br, 6H), 6.55 (dd, 6H, J = 8.6, 1.9 Hz), 6.89 (s, 3H), 6.91 (dd, 6H, J = 8.6, 1.9 Hz) FD-mass 477(M+)。
式（２９）に示す１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンを合成した。
【００８１】
【化４８】

【００８２】
実施例１
撹拌機、窒素導入管、温度計を備えたフラスコに、４，４’−ビス（３−アミノフェノキシ）ビフェニル９８ｍｍｏｌ、Ｎ，Ｎ−ジメチルアセトアミド２００．５ｇを装入し、窒素雰囲気下３０分間撹拌して溶解した。その後、ビス（３，４−ジカルボキシフェニル）エーテル二無水物１００ｍｍｏｌを溶液温度の上昇に注意しながら分割して加え、室温で６時間攪拌し、ポリアミド酸濃度２５重量％のポリアミド酸溶液２６７．３ｇを得た。得られたポリアミド酸のηinhは１．１７ｄｌ／ｇであった。
【００８３】
撹拌機、窒素導入管を備えたフラスコに得られたポリアミド酸溶液１３３．７ｇ（ポリアミド酸３３．４ｇ、分子末端酸無水物基２ｍｍｏｌ相当）にメタノール２ｍｍｏｌをＮ，Ｎ−ジメチルアセトアミド３３．３ｇで希釈した溶液を装入し、窒素雰囲気下６時間攪拌して加水分解し、分子末端がジカルボン酸またはそのメチルエステルであるポリアミド酸を得た。得られたワニス中のポリアミド酸のηinhは１．１２ｄｌ／ｇであった。
次に、合成例２で得られた１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン０．６７ｍｍｏｌを装入し、窒素雰囲気下６時間攪拌して溶解し、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１５ｄｌ／ｇであった。
【００８４】
得られたワニスの一部をガラス板上にキャストし、窒素気流下でキュア温度２５０℃まで４時間かけて昇温し、ワニスの脱溶媒・イミド化を行った。得られたポリイミドフィルムをガラス板より剥離し、Ｔｇ（ガラス転移温度）、Ｔｄ5%（５％重量減少温度）、Ｔ％（４２０nmにおける光線透過率、ＴＭＡ（引張伸び測定）、耐薬品性を評価した。結果を（表１）および（図１）に示す。ＴＭＡの測定結果より、得られたポリイミドフィルムはＴｇ以上の温度でも伸長せず、十分に架橋していることがわかる。
【００８５】
実施例２
キュア温度を３００℃とした他は実施例１と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００８６】
実施例３
キュア温度を２３０℃とした他は実施例１と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００８７】
実施例４
４，４’−ビス（３−アミノフェノキシ）ビフェニルを９５ｍｍｏｌ、Ｎ，Ｎ−ジメチルアセトアミドを１９７．１ｇおよびビス（３，４−ジカルボキシフェニル）エーテル二無水物１００ｍｍｏｌを用い、実施例１と同様にしてポリアミド酸濃度２５重量％のポリアミド酸溶液を得た。得られたワニス中のポリアミド酸のηinhは０．６５ｄｌ／ｇであった。
得られたポリアミド酸溶液２６２．８ｇ（ポリアミド酸６５．７ｇ、分子末端酸無水物基１０ｍｍｏｌ相当）およびメタノール１０ｍｍｏｌ、１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン３．３ｍｍｏｌを用い実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６４ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００８８】
実施例５
キュア温度を３００℃とした他は実施例４と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００８９】
実施例６
４，４’−ビス（３−アミノフェノキシ）ビフェニルを９０ｍｍｏｌ、Ｎ，Ｎ−ジメチルアセトアミドを１９１．７ｇおよびビス（３，４−ジカルボキシフェニル）エーテル二無水物１００ｍｍｏｌを用い、実施例１と同様にしてポリアミド酸濃度２５重量％のポリアミド酸溶液を得た。得られたワニス中のポリアミド酸のηinhは０．５９ｄｌ／ｇであった。得られたポリアミド酸溶液の２５５．６ｇ（ポリアミド酸６３．９ｇ、分子末端酸無水物基２０ｍｍｏｌ相当）およびメタノール２０ｍｍｏｌ、１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンを６.６７ｍｍｏｌを用い実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．５８ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９０】
実施例７
キュア温度を３００℃とした他は実施例６と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９１】
実施例８
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例１と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１３ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９２】
比較例１
実施例１で得られたポリアミド酸溶液の一部を、１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンを加えずに、ガラス板上にキャストし、窒素気流下でキュア温度２５０℃まで４時間かけて昇温し、ワニスの脱溶媒・イミド化を行った。得られたポリイミドフィルムの各評価結果を（表１）および（図１）に示す。ＴＭＡの測定結果より、得られたポリイミドフィルムはＴｇ以上で著しく伸び、形状を保持していないことがわかる。
【００９３】
比較例２
撹拌機、窒素導入管、温度計を備えたフラスコに、４，４’−ビス（３−アミノフェノキシ）ビフェニル１００ｍｍｏｌ、Ｎ，Ｎ−ジメチルアセトアミド２４８．２ｇを装入し、窒素雰囲気下３０分間撹拌して溶解した。その後、ビス（３，４−ジカルボキシフェニル）エーテル二無水物９８ｍｍｏｌを溶液温度の上昇に注意しながら分割して加え、室温で６時間攪拌し、ポリアミド酸濃度２０重量％のポリアミド酸溶液を得た。得られたポリアミド酸のηinhは０．７８ｄｌ／ｇであった。
撹拌機、窒素導入管を備えたフラスコに得られたポリアミド酸溶液５０ｇ（ポリアミド酸１０．０ｇ、分子末端アミノ基０．６４５ｍｍｏｌ相当）および無水マレイン酸０．６４５ｍｍｏｌを装入し、窒素雰囲気下２時間攪拌して溶解し、ワニスを得た。得られたワニス中のポリアミド酸のηinhは０．７８ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表１）および（図１）に示す。
【００９４】
比較例３
キュア温度を３００℃とした他は比較例２と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９５】
比較例４
メタノールを用いなかった他は実施例１と同様にワニス調製を行なったところ、合成例１で得られた１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン０．６７ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【００９６】
実施例９
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに１，４，５−トリアミノアントラキノンを用いた他は実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１５ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表１）および（図１）に示す。
【００９７】
実施例１０
キュア温度を３００℃とした他は実施例９と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９８】
実施例１１
キュア温度を２３０℃とした他は実施例９と同様にし、ポリイミドフィルムを得た。各評価結果を（表１）に示す。
【００９９】
実施例１２
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに１，４，５−トリアミノアントラキノンを用いた他は実施例４と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６２ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１００】
実施例１３
キュア温度を３００℃とした他は実施例１２と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０１】
実施例１４
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに１，４，５−トリアミノアントラキノンを用いた他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６０ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０２】
実施例１５
キュア温度を３００℃とした他は実施例１４と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０３】
実施例１６
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例９と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１５ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０４】
比較例５
メタノールを用いなかった他は実施例９と同様にワニス調製を行なったところ、１，４，５−トリアミノアントラキノン０．６７ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１０５】
実施例１７
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに３，４，４’−トリアミノジフェニルエーテルを用いた他は実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１４ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）および（図１）に示す。
【０１０６】
実施例１８
キュア温度を３００℃とした他は実施例１７と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０７】
実施例１９
キュア温度を２３０℃とした他は実施例１７と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０８】
実施例２０
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに３，４，４’−トリアミノジフェニルエーテルを用いた他は実施例４と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６２ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１０９】
実施例２１
キュア温度を３００℃とした他は実施例２０と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１１０】
実施例２２
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりに３，４，４’−トリアミノジフェニルエーテルを用いた他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６１ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１１１】
実施例２３
キュア温度を３００℃とした他は実施例２２と同様にし、ポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１１２】
実施例２４
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例１７と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１５ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表２）に示す。
【０１１３】
比較例６
メタノールを用いなかった他は実施例１７と同様にワニス調製を行なったところ、３，４，４’−トリアミノジフェニルエーテル０．６７ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１１４】
実施例２５
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりにメラミンを用いた他は実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１２ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）および（図１）に示す。
【０１１５】
実施例２６
キュア温度を３００℃とした他は実施例２５と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１１６】
実施例２７
キュア温度を２３０℃とした他は実施例２５と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１１７】
実施例２８
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりにメラミンを用いた他は実施例４と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６３ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１１８】
実施例２９
キュア温度を３００℃とした他は実施例２８と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１１９】
実施例３０
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンの代わりにメラミンを用いた他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６０ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２０】
実施例３１
キュア温度を３００℃とした他は実施例３０と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２１】
実施例３２
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例２５と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１３ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２２】
比較例７
メタノールを用いなかった他は実施例２５と同様にワニス調製を行なったところ、メラミン０．６７ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１２３】
実施例３３
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン０．６７ｍｍｏｌの代わりに３，３’−ジアミノベンジジン０．５０ｍｍｏｌを用いた他は実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１１ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）および（図１）に示す。
【０１２４】
実施例３４
キュア温度を３００℃とした他は実施例３３と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２５】
実施例３５
キュア温度を２３０℃とした他は実施例３３と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２６】
実施例３６
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン３．３ｍｍｏｌの代わりに３，３’−ジアミノベンジジン２．５ｍｍｏｌを用いた他は実施例４と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６３ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２７】
実施例３７
キュア温度を３００℃とした他は実施例３６と同様にし、ポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２８】
実施例３８
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン６．６７ｍｍｏｌの代わりに３，３’−ジアミノベンジジン５．００ｍｍｏｌを用いた他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６１ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表３）に示す。
【０１２９】
実施例３９
キュア温度を３００℃とした他は実施例３８と同様にし、ポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３０】
実施例４０
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例３３と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１６ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３１】
比較例８
メタノールを用いなかった他は実施例２９と同様にワニス調製を行なったところ、３，３’−ジアミノベンジジン０．５０ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１３２】
比較例９
特公昭４０−１２８４６号公報に記載されている実施例１に従い、ポリアミド酸ワニスを調製した。即ち、まずジメチルフォルムアミドを温度計および撹拌機を取り付けたフラスコに収容し、この反応装置をの内部温度を２０℃以下に保つため氷水中にセットして撹拌した。次に、ピロメリット酸二無水物１００ｍｍｏｌ、４，４’−ジアミノジフェニルプロパン９２．３ｍｍｏｌおよび３，３’−ジアミノベンジジン０．１５ｍｍｏｌを溶液温度の上昇に注意しながら少量ずつジメチルフォルムアミド溶媒中に添加し，更にポリアミド酸濃度が２０重量％になるようジメチルフォルムアミドを添加して撹拌したところ、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１３３】
実施例４１
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン０．６７ｍｍｏｌの代わりに３，３’，４，４’−テトラアミノジフェニルエーテル０．５０ｍｍｏｌを用いた他は実施例１と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１３ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表４）及び（図１）に示す。
【０１３４】
実施例４２
キュア温度を３００℃とした他は実施例４１と同様にし、ポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３５】
実施例４３
キュア温度を２３０℃とした他は実施例４１と同様にし、ポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３６】
実施例４４
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン３．３ｍｍｏｌの代わりに３，３’，４，４’−テトラアミノジフェニルエーテル２．５ｍｍｏｌを用いた他は実施例４と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６６ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３７】
実施例４５
キュア温度を３００℃とした他は実施例４４と同様にし、ポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３８】
実施例４６
１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼン６．６７ｍｍｏｌの代わりに３，３’，４，４’−テトラアミノジフェニルエーテル５．００ｍｍｏｌを用いた他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６１ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１３９】
実施例４７
キュア温度を３００℃とした他は実施例４６と同様にし、ポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１４０】
実施例４８
メタノール２ｍｍｏｌの代わりに水２ｍｍｏｌを用いた以外は、実施例４１と同様にして、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは１．１４ｄｌ／ｇであった。実施例１と同様にしてポリイミドフィルムを得た。各評価結果を（表４）に示す。
【０１４１】
比較例１０
メタノールを用いなかった他は実施例４１と同様にワニス調製を行なったところ、３，３’，４，４’−テトラアミノジフェニルエーテル０．５０ｍｍｏｌを装入し、窒素雰囲気下攪拌を行った際、短時間で粘度が著しく上昇、撹拌が出来なくなった。ポリアミド酸が架橋したものと思われ、反応マスはゼリー状にゲル化していた。
【０１４２】
比較例１１
用いた１，３，５−トリス（１−（４−アミノフェニル）−１−メチルエチル）ベンゼンを０.６７ｍｍｏｌとし、メタノールを用いなかった他は実施例６と同様にし、本発明のワニスを得た。得られたワニス中のポリアミド酸のηinhは０．６０ｄｌ／ｇであった。実施例１と同様にして得られたポリイミドフィルムの各評価結果を（表４）および（図１）に示す。得られたポリイミドフィルムは用いたトリアミン量が少なく、十分な架橋構造をとっていないため、Ｔｇ以上で著しく伸び、形状を保持していないことが判る。
【０１４３】
【表１】

【０１４４】
【表２】

【０１４５】
【表３】

【０１４６】
【表４】

【０１４７】
【発明の効果】
本発明のワニスは、含有する分子末端がジカルボン酸またはジエステルであるポリアミド酸が架橋部位を有さない直鎖状であるため、通常のポリアミド酸ワニスと同様の取り扱い、すなわち、流延、キャスト等が出来、さらに、通常の熱処理によりイミド化と同時に３または４個のアミノ基を有する化合物と反応することにより架橋構造を形成するため、従来公知の直鎖状ポリイミドの製造条件により架橋ポリイミドを得ることが出来る。
本発明のワニスを熱処理して得られる架橋ポリイミドは、架橋により生成する結合がイミド結合であるため、他の架橋基を用いた場合に比べ、高い分解温度を有する。また、架橋により、直鎖ポリイミドに比べ、高い耐熱性、耐薬品性を有する。
【図面の簡単な説明】
【図１】 ポリイミドフィルムの引張伸び測定結果[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a varnish and a crosslinked polyimide obtained therefrom.
[0002]
[Prior art]
Polyimide was developed by DuPont in the 1960s as a material for the aerospace industry. This polyimide “Kapton” (DuPont) has excellent heat resistance, mechanical characteristics, electrical characteristics, etc., and the high reliability obtained in space industry applications enables it to be used in aircraft and industrial equipment. Its application has expanded, and today it is widely used as a heat-resistant insulating material for electrical and electronic use and has become an essential material. In particular, as electronics continues to develop tremendously, as devices become smaller and lighter, with more functions and higher performance, high reliability is demanded for materials, focusing on applications in the field of electronic equipment. The market is expanding.
[0003]
Aromatic polyimide represented by “Kapton” is often used in the form of a film in terms of quantity, and the amount used in the world exceeds 1000 tons / year. “Kapton” is an organic insulating material having the highest heat resistance. However, various problems have been pointed out with the expansion of applications and the sophistication of required characteristics. For example, “Kapton” is a problem that the water absorption rate is high, the strength and dimensional change accompanying water absorption are large, the linear expansion is large, and the film warps when bonded to a metal foil.
[0004]
Many companies and research institutions have synthesized many polyimides from various diamines and acid anhydrides in order to solve the problems associated with such expansion of applications and sophistication of required properties. Chemical and physical properties have been studied. The latest R & D trends are described in detail in “Latest Polyimide Trends II” (published by Sumibe Techno Research).
[0005]
When diamines and acid anhydrides that are monomers are changed and various properties are imparted to polyimide, the heat resistance and chemical resistance, which are the characteristics of polyimide, often deteriorate. For example, “Upilex” (Ube Industries), which is a high-strength and low linear expansion polyimide, is known to have lower glass transition temperature and chemical resistance than “Kapton” (T. Nakano; 2nd Intern. Conf. on PI. 163-181 (1985)). In addition, it is known that polyimide introduced with fluorine or silicone has low glass transition temperature and chemical resistance.
[0006]
It is known that heat resistance and chemical resistance such as the decomposition temperature and glass transition temperature of a resin can be improved by introducing a crosslinked structure into the resin. However, since polyimide is generally synthesized through a polyamic acid that is a precursor thereof, it is difficult to introduce a crosslinked structure. For example, “Upilex”, which is a typical polyimide film, prepares a solution of a precursor polyamic acid, casts it on a drum or belt, and then is heated to remove an appropriate amount of solvent. Thus, a polyamic acid film having a self-supporting property is obtained, then peeled off from the drum or belt, and further a polyimide film is produced by proceeding with an imidization reaction by high-temperature post-heating treatment or the like (Hiroshi Mouri; Journal of Textile Society of Japan “FIBER”, Vol.50, p96-101 (1994)). At that time, since the polyamic acid film having a self-supporting property cannot be obtained unless the molecular weight of the polyamic acid is high to some extent, it is difficult to produce a polyimide film itself. Further, when the molecular weight of the polyamic acid is too high or infinite, it cannot be handled as a solution such as casting, so that a polyimide film cannot be produced.
[0007]
That is, when a monomer having a trifunctional or higher functional group is used to introduce a crosslinked structure for the purpose of improving heat resistance and chemical resistance, as shown in JP-A-4-88020, a precursor is used. In the polyamic acid which is a body, it was cross-linked and gelled, and there was a problem that it could not be handled as a solution such as casting.
[0008]
In Japanese Patent Publication No. 40-12846, it is obtained by reacting tetracarboxylic dianhydrides, diamines and aromatic tetramines in an organic solvent in order to obtain a heat-resistant insulated wire coated with a polyimide resin. The polyamic acid composition solution was coated and baked on the conductor, but when trying to prepare the polyamic acid composition solution based on the practical examples described, gelation occurred while stirring. The solution could not be obtained.
[0009]
For the reasons described above, crosslinked polyimide is usually synthesized by a method in which a crosslinked structure is introduced into the main chain or terminal of the polyimide and is crosslinked after molding (Yokota Rikio; “Reinforced Plastics”, Vol. 43, No. 6, 205-211). (1999), Vol. 43, No. 9, 318-329 (1999), Takeshi Riki; Polymer, 46 (8), 576 (1997), etc.).
However, most of the cross-linking methods that have been developed so far are mostly based on addition reaction, and it is necessary to treat at higher temperature after imidization in order to cross-link. There were many problems such as oxidation of the material. Moreover, since the crosslinked structure produced | generated by addition reaction is a coupling | bonding containing an aliphatic chain with low heat resistance, the high decomposition temperature of a polyimide was impaired. A cross-linked polyimide combining the above two methods is also shown (Roberto. J. Cano; 44 ^th International SAMPE Symposium Exhib. 44 1780-1791 (1999)), it is described that a triamine compound is used to introduce a branched structure into the main chain in advance, and that these polymers are crosslinked by addition reaction, but at the expense of the high decomposition temperature of polyimide. There was no change in being.
[0010]
In recent years, new polymer materials called dendrimers or hyperbranched polymers have been discovered, and polyimide structures have been studied (K. Yamanaka; Macromolecules, 33 1111 (2000)), since these molecules are not chemically bonded to each other and have little physical entanglement, their heat resistance and chemical resistance are not significantly different from those of a straight chain. In JP-A-7-247357, a tetraamino compound or a triamino compound is used to obtain a melt-flowable polyimide that can be injection-molded. By using a monofunctional end-capping agent in combination, The molecular weight is adjusted so as not to be infinite. That is, the polyimide obtained here corresponds to a hyperbranched polymer having a branch, not a network-like crosslinked polyimide.
[0011]
From the above, there has been a demand for a polyimide crosslinking method that can be crosslinked under general polyimide production conditions and can improve the heat resistance and chemical resistance of various polyimides.
[0012]
[Problems to be solved by the invention]
The objective of this invention is providing the crosslinking method of the polyimide which can be bridge | crosslinked on the manufacturing conditions of a general polyimide, and can improve the heat resistance of various polyimides, and chemical resistance.
[0013]
[Means for Solving the Problems]
As a result of intensive studies in order to solve the above problems, the present inventors have found that polyamic acid whose molecular terminal is dicarboxylic acid or an ester thereof does not react with a compound having 3 or 4 amino groups. In the state of acid varnish, the crosslinking reaction does not proceed, and it reacts under normal imidization conditions to give a crosslinked polyimide. Since the obtained crosslinked polyimide has an imide bond in its crosslinked structure, it has a high decomposition temperature. The present invention was completed.
[0014]
That is, the present invention relates to a varnish comprising a compound having 3 or 4 amino groups, and a polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof, and a crosslinked polyimide obtained by heat-treating the varnish. And a manufacturing method thereof.
[0015]
Since the varnish of the present invention is a straight chain with no cross-linked site, the same varnish can be handled, i.e., cast, cast, etc., as well as imide by ordinary heat treatment. Since a crosslinked structure is formed at the same time as the formation, a crosslinked polyimide can be obtained under the conventionally known production conditions for linear polyimides.
[0016]
The cross-linked polyimide obtained by heat-treating the varnish of the present invention has a higher decomposition temperature than the case where other cross-linking groups are used because the bond generated by cross-linking is an imide bond. Moreover, it has high heat resistance and chemical resistance compared with a linear polyimide by bridge | crosslinking. Furthermore, due to crosslinking, it is expected to have a high elastic modulus and mechanical strength not only in the temperature range above the glass transition temperature but also in the vicinity of room temperature.
[0017]
The present invention provides a polyimide crosslinking method that can be crosslinked under general polyimide production conditions and can improve the heat resistance and chemical resistance of various polyimides.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be specifically described below.
The present invention relates to a varnish characterized by comprising a compound having 3 or 4 amino groups, and a polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof, and a crosslinked polyimide obtained by heat-treating it, and It is the manufacturing method.
[0019]
The varnish of the present invention comprises a compound having 3 or 4 amino groups, and a polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof.
[0020]
Since the polyamic acid whose molecular terminal is a carboxylic acid or an ester thereof does not undergo an amidation reaction with a compound having an amino group at room temperature, the varnish is not crosslinked. The polyamic acid whose molecular end is a carboxylic acid or its ester is dehydrated or dealcoholated under conditions where a varnish is applied, solvent-removed, or imidized to produce an acid anhydride group at the molecular end. The polymer is cross-linked through reaction with the amino group of the compound having an amino group, generation of amic acid and imidization thereof.
[0021]
In addition, when the polyamic acid whose molecular terminal is an acid anhydride group is used, the compound reacts with an amino group of a compound having 3 or 4 amino groups at room temperature, the polyamic acid is crosslinked, and the varnish is gelled. Therefore, it is not preferable.
[0022]
The dicarboxylic acid of the polyamic acid or the ester terminal thereof in the present invention is preferably represented by the following formula (1-a) or (1-b).
[0023]
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[0024]
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[0025]
(Where R ₁ Represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms or an aromatic group. In addition, in the formula (1-a), the dicarboxylic acid or the opposite side of the ester terminal may have any structure)
R ₁ As a specific example of
[0026]
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Etc.
[0027]
Specific examples of the compound having 3 or 4 amino groups include compounds represented by the following formulas (2), (5), (7) and (12).
[0028]
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(Where n is 3 or 4, R ₂ Represents a trivalent or tetravalent group represented by the following formula (3). )
[0029]
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(Where R _Three Represents a divalent group represented by the following formula (4). )
[0030]
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[0031]
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(Where R _Four Is -NH ₂ Or -H and R _Five Represents a divalent group represented by the following formula (6). )
[0032]
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[0033]
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(Where R ₆ Represents a monovalent group represented by the following formula (8), and R ₇ Represents a monovalent group represented by the following formula (9), and R ₈ Represents a divalent group represented by the following formula (10))
[0034]
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(Where R ₉ Represents a divalent group represented by the following formula (11). )
[0035]
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(Where R ₉ Represents a divalent group represented by the following formula (11). )
[0036]
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[0037]
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[0038]
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(Where R _Ten Represents a trivalent group represented by N or CH. )
[0039]
Specific examples include, for example, tris (p-aminophenyl) amine, tris (3-aminophenyl) phosphine oxide, tris (4-aminophenyl) methane, 1,3,5-tris (4-aminophenoxy) benzene. 1,3,5-tris (3-aminophenoxy) benzene, 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene, triaminopyrimidine, melamine and the following formula (20 ) To (27).
These can be used alone or in combination of two or more.
[0040]
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[0041]
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[0042]
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[0043]
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[0044]
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[0045]
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[0046]
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[0047]
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[0048]
In the present invention, the amount of the compound having 3 or 4 amino groups to be used is preferably 0.1 to 0.6 mol, more preferably 0.1 mol, per 1 mol of the polycarboxylic acid dicarboxylic acid or its ester terminal. 2 to 0.4 mol. When the amount of the compound used is large or small, there are many uncrosslinked molecular chains in the resulting polyimide, and the effect of improving heat resistance and chemical resistance tends to be small. Here, 1 mol of dicarboxylic acid or its ester terminal represents 1 mol of the terminal structure represented by the above formula (1-a) or (1-b).
[0049]
In the present invention, the repeating unit possessed by the polyamic acid whose molecular end is a dicarboxylic acid or an ester thereof is not particularly limited, and can be arbitrarily selected from conventionally known polyamic acid repeating units. The polyamic acid of the present invention preferably has a repeating structure represented by the following formula (13).
[0050]
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(Here, X represents a divalent aromatic group, more preferably a divalent aromatic group selected from the following formula (14).)
[0051]
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(Here, some of the hydrogen atoms of the aromatic ring of the formula (14) may be substituted with a substituent having no reactivity with an amino group or a carbonyl group. R ₁₁ Are independent and represent a divalent group represented by the following formula (15))
[0052]
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[0053]
(Y represents a tetravalent aromatic group, more preferably a tetravalent aromatic group selected from the following formula (16).)
[0054]
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[0055]
Here, the polyamic acid of the present invention may have two or more kinds of repeating units selected from the aforementioned repeating structures. In this case, there is no limitation on the mole fraction, the number of repetitions, the ordering order, and the regularity of two or more types of repeating units.
[0056]
There is no particular limitation on the molecular weight of the polyamic acid in which the molecular terminal of the present invention is a dicarboxylic acid or its ester, and it can be arbitrarily set according to the viscosity of the varnish, the physical properties of the resulting crosslinked polyimide, etc. In the range of 0.2 to 2.0 dl / g (measured in N, N-dimethylacetamide at a concentration of 0.5 g / dl at 35 ° C.), 0.4 to 1.2 dl / g The range of g is particularly preferable. When the logarithmic viscosity is less than 0.2, the strength of the polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof is low, and there is a possibility that the coating film may be broken when a varnish is applied or imidized. In the case of 2.0 or more, since the terminal carboxylic acid groups and / or ester groups of the resulting polyamic acid are extremely few, it may be difficult to obtain the effect of improving physical properties by crosslinking. The polyamic acid having a molecular terminal of a dicarboxylic acid or ester thereof according to the present invention can be obtained by adding water or alcohol to a general acid anhydride-terminated polyamic acid and converting the terminal to a dicarboxylic acid or ester thereof. it can.
[0057]
The polyamic acid at the terminal of the acid anhydride to be used can be obtained by using less than an equivalent amount of aromatic diamine with respect to tetracarboxylic dianhydride. The polyamic acid used in the present invention controls the amount of terminal group of the polyamic acid obtained, the viscosity of the varnish, and the cross-linking density (distance between cross-linking points) of the resulting cross-linked polyimide by adjusting the amount of the aromatic diamine used. I can do it.
[0058]
In the synthesis of the polyamic acid at the terminal of the acid anhydride used in the present invention, it is preferable to use 0.8 to 0.99 mol of diamine with respect to 1 mol of tetracarboxylic dianhydride. When the amount of diamine to be used is small, the strength of the resulting polymer is low, and the coating film is cracked when applying and imidizing the varnish, which is not preferable. Moreover, when there are many, since the acid anhydride terminal of the polyamic acid obtained is extremely few, it may be unable to bridge | crosslink fully. When 1 mol of tetracarboxylic dianhydride and α mol of diamine are used, the amount of terminal acid anhydride of the resulting polyamic acid is (1−α) × 2 mol.
[0059]
Further, there is no particular limitation on the method for producing the polyamic acid at the terminal of the acid anhydride to be used, and it can be obtained from a conventionally known aromatic diamine and aromatic tetracarboxylic dianhydride by a conventionally known method, and the order of raw material charging There is no limitation on the reaction concentration, temperature, and time. In general, the polyamic acid is obtained by reacting diamine and tetracarboxylic dianhydride at room temperature to about 60 ° C. for several hours in an aprotic polar solvent under an inert gas atmosphere. The acid anhydride-terminated polyamic acid used in the present invention may be synthesized in a solvent and dissolved in the solvent, or may be precipitated using a poor solvent to form a solid state. .
[0060]
Here, conventionally known aromatic diamines that can be used include, for example, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3, 4'-diaminodiphenyl ether, bis (3-aminophenyl) sulfide, bis (4-aminophenyl) sulfide, (3-aminophenyl) (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfoxide, bis (4 -Aminophenyl) sulfoxide, (3-aminophenyl) (4-aminophenyl) sulfoxide, bis (3-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, (3-aminophenyl) (4-aminophenyl) Sulfone, 3,3′-diaminobenzophenone, 4,4′-diaminobenzophenone, 3,4′-diaminobenzophenone, 1,3-bis (3-aminophenoxy) Zen, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-amino) Phenoxy) benzene, 4,4′-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4 -Aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfoxide, Bis [4- (4-aminophenoxy) phenyl] sulfoxide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-amino Phenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether 3,3'-diamino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4,5'-diphenoxybenzophenone, 3, 3'-diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoxybenzophenone, 3,3 '-Diamino-4,4'-dibiphenoxybenzophenone, 4,4'-diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino-4,5'-dibiphenoxybenzophenone, 3,3'- Diamino-4-biphenoxybenzophenone, 4,4′-diamino-5-biphenoxybenzophenone, 3,4′-diamino-4-biphenoxybenzophenone, 3,4′-diamino-5′-biphenoxybenzophenone, 2, 2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 2-trifluoromethyl-4,4'- Aminodiphenyl ether, 2'-trifluoromethyl-3,4'-diaminodiphenyl ether, 2,2-bis (3-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 2,2- Bis (4-aminophenyl) -1,1,1,3,3,3-hexafluoropropane, 1,3-bis (3-aminophenoxy) -4-trifluoromethylbenzene, 1,3-bis (3 -Aminophenoxy) -5-trifluoromethylbenzene, 1,3-bis (3-amino-5-trifluoromethylphenoxy) benzene, 1,4-bis (3-amino-5-trifluoromethylphenoxy) benzene, 1,3-bis (3-amino-5-trifluoromethylphenoxy) -5-trifluoromethylbenzene, 1,3-bis (3-amino-5-trifluoromethylphenoxy) -4-trifluoromethylbenzene, 1,3-bis (4-amino-2-trifluoromethylphenoxy) benzene, 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene Zen, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl ] -1,1,1,3,3,3-hexafluoropropane and the like, and these can be used alone or in admixture of two or more.
[0061]
Here, conventionally known aromatic tetracarboxylic dianhydrides that can be used include, for example, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 2,3 ', 3,4'-Benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,3 ', 3,4'-biphenyltetracarboxylic dianhydride 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 2 , 2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, etc., and these should be used alone or in combination of two or more. I can do it.
[0062]
Here, the reaction solvent that can be used for the synthesis of the polyamic acid is not particularly limited. For example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, hexamethylphosphorotriamide, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) Examples include ethane, tetrahydrofuran, bis [2- (2-methoxyethoxy) ethyl] ether, 1,4-dioxane, dimethyl sulfoxide, dimethyl sulfone, diphenyl ether, sulfolane, diphenyl sulfone, tetramethyl urea, and anisole. These solvents may be used alone or in combination of two or more.
[0063]
The varnish of the present invention comprises a compound having 3 or 4 amino groups and a polyamic acid whose molecular end is a dicarboxylic acid or an ester thereof, and the molecular end obtained by the above-described method for producing polyamic acid is an acid. It is obtained by adding water or alcohol to a polyamic acid solution which is an anhydride group to convert a terminal acid anhydride group to a dicarboxylic acid or an ester thereof, and then dissolving a compound having 3 or 4 amino groups. I can do it.
[0064]
In addition, a solid polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof, a polyamic acid solution whose molecular terminal is a dicarboxylic acid or an ester thereof, and a compound having 3 or 4 amino groups Can be dissolved. In addition, the varnish of the present invention is not particularly limited in the concentration of the compound having 3 or 4 amino groups and the polyamic acid whose molecular terminal is dicarboxylic acid or an ester thereof, depending on the storage stability and coatability of the varnish. It can be arbitrarily prepared.
[0065]
The varnish of the present invention includes a compound having 3 or 4 amino groups and a polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof, a catalyst for promoting imidization, solvent removability, and varnish viscosity. Solvents for changing storage stability, coupling materials for adjusting adhesion to substrates, fillers for changing the properties of the resulting cross-linked polyimide (eg fiber reinforcement, silica, alumina, mica, talc, fine powder Metal etc.) may be included.
[0066]
The polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof according to the present invention can be obtained by adding a water or alcohol to the polyamic acid whose molecular terminal is an acid anhydride to cause hydrolysis. The hydrolysis reaction mechanism is expected as shown in formula (28) (in the reaction formula, A represents a polyamic acid main chain portion, R represents hydrogen, a hydrocarbon group having 1 to 10 carbon atoms, or an aromatic group). ).
[0067]
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[0068]
First, by adding water or alcohol to the polyamic acid whose molecular terminal is an acid anhydride, the amide bond in the polyamic acid main chain is hydrolyzed to cleave the main chain, and the terminal is an amino group and an acid anhydride group. Two types are produced: polyamic acid, polycarboxylic acid having a terminal dicarboxylic acid or ester thereof and an acid anhydride group. Next, it is expected that the generated amino group terminal and the original acid anhydride terminal undergo an amidation reaction, and as a result, a polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof is generated.
[0069]
In this invention, it is preferable to use 1-2 mol of water and / or alcohol with respect to 1 mol of terminal dicarboxylic anhydride groups. When the amount of water and / or alcohol used is small, the hydrolysis reaction does not proceed sufficiently, so that the dicarboxylic anhydride group remains at the end of the polyamic acid, and the compound having 3 or 4 amino groups to be added later easily There is a possibility of cross-linking by reaction and gelation. In addition, in many cases, the amide bond in the polyamic acid main chain is hydrolyzed more than necessary, and an excess amino group terminal that cannot be amidated with the acid anhydride terminal is generated, resulting in a decrease in molecular weight and heat resistance. There is a risk of lowering.
[0070]
Here, in order to produce a polyamic acid whose molecular end is a dicarboxylic acid or an ester thereof, examples of compounds that can be used to hydrolyze the polyamic acid at the end of an acid anhydride group include, for example, water, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl Examples include -1-butanol, 2-methyl-2-butanol, 1-hexanol, 2-hexanol, 3-hexanol, phenol, and cresol. These water and / or alcohol may be used alone or in combination of two or more.
[0071]
The crosslinked polyimide of the present invention reacts with a compound having 3 or 4 amino groups by dehydrating or dealcoholizing the terminal group of the polyamic acid whose molecular terminal is a dicarboxylic acid or an ester thereof to form an acid anhydride terminal during imidization. Thus, it is a crosslinked polyimide formed by the generation of amic acid and its imidization. The crosslinked polyimide of the present invention exhibits a high glass transition temperature and high chemical resistance as compared to an uncrosslinked linear polyimide. Moreover, since the crosslinked structure is an imide bond, the decomposition temperature is higher than that of a crosslinked polyimide obtained by another crosslinking method. Furthermore, the crosslinked polyimide of the present invention is expected to have higher mechanical strength, sliding, wear, and fatigue properties than uncrosslinked linear polyimide.
[0072]
The crosslinked polyimide of the present invention can be obtained by imidation reaction of a polyamic acid whose molecular end is a carboxylic acid of the present invention, which is a dicarboxylic acid or an ester thereof, and a reaction of a compound having 3 or 4 amino groups with a polyamide end. I can do it. In the present invention, the imidization method is not particularly limited, and a conventionally known chemical or thermal imidization method can be used. As an imidization method, for example, after drying the varnish coated on the substrate with hot air, peeling from the substrate and further heat treating at a high temperature, a method of heat treating at a high temperature while attached to the substrate, acetic anhydride, etc. A method of chemically dehydrating and imidizing by immersing in a dehydrating agent is exemplified.
[0073]
When producing the crosslinked polyimide by thermal imidization of the varnish of the present invention, the normal imidization conditions of the polyamic acid are sufficient as the imidization conditions, and further high-temperature treatment for crosslinking and long-time annealing treatment. Is not necessary. Although there is no restriction | limiting in the temperature at the time of thermal imidation, in order to suppress deterioration by oxidation etc. of resin obtained or a base material, it is especially preferable that it is 300 degrees C or less.
[0074]
In the varnish of the present invention, since the polyamic acid contained therein is a straight chain having no cross-linking site, it can be handled in the same manner as a normal polyamic acid varnish, that is, cast, cast, etc. Since a cross-linked structure is formed simultaneously with imidization, a cross-linked polyimide can be obtained under the conventionally known production conditions for linear polyimide.
[0075]
The crosslinked polyimide of the present invention is a film, a coating material for electric wires and optical fibers, a coating material for electronics (interlayer insulation film, passivation film, etc.), a circuit board laminated with a metal foil, etc., a base film for magnetic tape, and a fiber reinforced composite material It is useful as a matrix resin and a sliding member.
[0076]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to these Examples.
[0077]
Each evaluation method in the examples is shown below.
Logarithmic viscosity (ηinh): A polyamide solution corresponding to a resin amount of 0.5 g was dissolved in dimethylacetamide to make 100 ml, and then measured at 35 ° C. with an Ubbelohde viscometer.
Glass transition temperature (Tg): Measured by DSC (Differential Scanning Calorimeter, Shimadzu DSC-60) from 25 ° C. to 430 ° C. at a heating rate of 10 ° C./min.
5% weight loss temperature (Td5%): Measured in air by TGA (Thermogravimetric apparatus, Shimadzu Corporation TGA-50).
[0078]
Light transmittance (T%): The light transmittance at 420 nm of a cast film having a thickness of 50 micrometers was measured using UV (ultraviolet visible absorptiometer, manufactured by JASCO Corporation, V-550).
Elongation: Measurement of tensile elongation of a strip-like film (thickness 50 micrometers, width 5.0 mm, measurement length 15.0 mm) using TMA (thermomechanical analyzer, manufactured by Shimadzu Corporation, TMA-50) (loading 3.0 g) And a temperature rising rate of 5 ° C./min).
Chemical resistance: 0.5 g of a polyimide film was placed in 100 ml of a mixed solvent of 90% by weight of p-chlorophenol / 10% by weight of phenol, heated and stirred at 180 ° C. for 10 minutes, and the presence or absence of dissolution was visually observed.
[0079]
Synthesis example 1
Synthesis of 1,3,5-tris (1- (4-amino-3-chlorophenyl) -1-methylethyl) benzene
In a 200 ml three-necked reaction vessel, 1.98 g of activated clay, 127.57 g (1.00 mol) of 2-chloroaniline, 20.87 g of 1,3,5-triisopropenylbenzene (purity 95% by mass, 0.10 mol) The mixture was stirred and stirred at 210 ° C. for 3 hours. The mixture was cooled to 100 ° C. and activated clay was filtered off. The filtrate was analyzed by high performance liquid chromatography (HPLC). As a result, the target 1,3,5-tris (1- (4-amino-3-chlorophenyl) -1-methylethyl) benzene was 86.5%. It was produced in a reaction yield. Excess 2-chloroaniline was distilled off under reduced pressure, and then 42.8 g (purity 95% by mass, 70 mmol, isolated yield 70%) of the target product was obtained. The physical properties of the target are as follows.
Melting point 108.0-109.0 ℃
¹ H-NMR (CDCl _Three ) δ: 1.46 (s, 18H), 3.90 (s, 6H), 6.60 (d, 3H, J = 8.4 Hz), 6.75 (dd, 3H, J = 8.4, 1.9 Hz), 6.84 (s, 3H), 7.01 (d, 3H, J = 1.9 Hz)
FD-mass 528 (M +)
[0080]
Synthesis example 2
Synthesis of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene
In a 100 ml three-necked reaction vessel, 30 ml of aniline and 10.36 g (80 mmol) of aniline hydrochloride were added under a nitrogen atmosphere, and the temperature was raised to 150 ° C. To the reaction solution, 5.0 g of 1,3,5-tris (1-chloro-1-methylethyl) benzene (purity 75% by mass, 12.2 mmol) was added at 150 ° C., and then at 180 ° C. for 5 hours. Stir. The reaction solution was cooled to 150 ° C. and added to a mixed solvent of 200 ml of hexane and 400 ml of ethyl acetate to precipitate crystals. After cooling to 15 ° C., the crystals were filtered off. The resulting crystals were reslurried in 200 ml of water to remove aniline hydrochloride. The crystals were filtered off, dispersed in a mixed solution of 50 ml of ethyl acetate and 50 ml of water, and neutralized using a 10% aqueous sodium hydroxide solution. After separation of the organic phase, the solvent was concentrated. Recrystallization was performed using hexane, and 3.88 g (purity 98% by mass, 8.1 mmol, simple substance) of the target 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene was obtained. (Separation yield 66%). The physical properties of the target are as follows.
Melting point 143.3-143.8 ℃
¹ H-NMR (CDCl _Three ) δ: 1.52 (s, 18H), 3.53 (br, 6H), 6.55 (dd, 6H, J = 8.6, 1.9 Hz), 6.89 (s, 3H), 6.91 (dd, 6H, J = 8.6, 1.9 Hz) ) FD-mass 477 (M +).
1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene represented by the formula (29) was synthesized.
[0081]
Embedded image

[0082]
Example 1
A flask equipped with a stirrer, a nitrogen inlet tube, and a thermometer was charged with 98 mmol of 4,4′-bis (3-aminophenoxy) biphenyl and 200.5 g of N, N-dimethylacetamide, and stirred for 30 minutes in a nitrogen atmosphere. And dissolved. Thereafter, 100 mmol of bis (3,4-dicarboxyphenyl) ether dianhydride was added in portions while paying attention to an increase in the solution temperature, stirred at room temperature for 6 hours, and a polyamic acid solution having a polyamic acid concentration of 25% by weight. 3 g was obtained. Ηinh of the obtained polyamic acid was 1.17 dl / g.
[0083]
Stirrer, 133.7 g of polyamic acid solution obtained in a flask equipped with a nitrogen introduction tube (33.4 g of polyamic acid, equivalent to 2 mmol of molecular terminal acid anhydride group) was added 2 mmol of methanol with 33.3 g of N, N-dimethylacetamide. The diluted solution was charged and hydrolyzed by stirring for 6 hours under a nitrogen atmosphere to obtain a polyamic acid whose molecular terminal was a dicarboxylic acid or its methyl ester. Ηinh of the polyamic acid in the obtained varnish was 1.12 dl / g.
Next, 0.67 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene obtained in Synthesis Example 2 was charged and dissolved by stirring for 6 hours in a nitrogen atmosphere. Thus, the varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 1.15 dl / g.
[0084]
A part of the obtained varnish was cast on a glass plate, heated to a cure temperature of 250 ° C. over 4 hours under a nitrogen stream, and the varnish was desolvated and imidized. The obtained polyimide film was peeled off from the glass plate, and Tg (glass transition temperature), Td5% (5% weight loss temperature), T% (light transmittance at 420 nm, TMA (tensile elongation measurement), and chemical resistance were evaluated. The results are shown in (Table 1) and (FIG. 1) From the measurement results of TMA, it can be seen that the obtained polyimide film does not stretch even at a temperature of Tg or higher and is sufficiently crosslinked.
[0085]
Example 2
A polyimide film was obtained in the same manner as in Example 1 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 1).
[0086]
Example 3
A polyimide film was obtained in the same manner as in Example 1 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 1).
[0087]
Example 4
As in Example 1, using 95 mmol of 4,4′-bis (3-aminophenoxy) biphenyl, 197.1 g of N, N-dimethylacetamide and 100 mmol of bis (3,4-dicarboxyphenyl) ether dianhydride Thus, a polyamic acid solution having a polyamic acid concentration of 25% by weight was obtained. The polyamic acid ηinh in the obtained varnish was 0.65 dl / g.
262.8 g of the resulting polyamic acid solution (65.7 g of polyamic acid, equivalent to 10 mmol of molecular terminal acid anhydride group) and 10 mmol of methanol, 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl The varnish of the present invention was obtained in the same manner as in Example 1 using 3.3 mmol of benzene. The polyamic acid ηinh in the obtained varnish was 0.64 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 1).
[0088]
Example 5
A polyimide film was obtained in the same manner as in Example 4 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 1).
[0089]
Example 6
As in Example 1, using 90 mmol of 4,4′-bis (3-aminophenoxy) biphenyl, 191.7 g of N, N-dimethylacetamide and 100 mmol of bis (3,4-dicarboxyphenyl) ether dianhydride Thus, a polyamic acid solution having a polyamic acid concentration of 25% by weight was obtained. The polyamic acid ηinh in the obtained varnish was 0.59 dl / g. 255.6 g (corresponding to polyamic acid 63.9 g, molecular terminal acid anhydride group 20 mmol) and methanol 20 mmol, 1,3,5-tris (1- (4-aminophenyl) -1-methyl of the obtained polyamic acid solution Ethyl) benzene was used in the same manner as in Example 1 using 6.67 mmol to obtain a varnish of the present invention. Ηinh of the polyamic acid in the obtained varnish was 0.58 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 1).
[0090]
Example 7
A polyimide film was obtained in the same manner as in Example 6 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 1).
[0091]
Example 8
A varnish of the present invention was obtained in the same manner as in Example 1 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.13 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 1).
[0092]
Comparative Example 1
A part of the polyamic acid solution obtained in Example 1 was cast on a glass plate without adding 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene, Under a nitrogen stream, the temperature was raised to a curing temperature of 250 ° C. over 4 hours, and the varnish was desolvated and imidized. Each evaluation result of the obtained polyimide film is shown in (Table 1) and (FIG. 1). From the measurement result of TMA, it can be seen that the obtained polyimide film is remarkably elongated at Tg or more and does not retain its shape.
[0093]
Comparative Example 2
A flask equipped with a stirrer, a nitrogen inlet tube, and a thermometer was charged with 100 mmol of 4,4′-bis (3-aminophenoxy) biphenyl and 248.2 g of N, N-dimethylacetamide, and stirred for 30 minutes in a nitrogen atmosphere. And dissolved. Thereafter, 98 mmol of bis (3,4-dicarboxyphenyl) ether dianhydride was added in portions while paying attention to an increase in the solution temperature, and stirred at room temperature for 6 hours to obtain a polyamic acid solution having a polyamic acid concentration of 20% by weight. It was. Ηinh of the obtained polyamic acid was 0.78 dl / g.
A flask equipped with a stirrer and a nitrogen introducing tube was charged with 50 g of the polyamic acid solution (10.0 g of polyamic acid, equivalent to 0.645 mmol of the molecular terminal amino group) and 0.645 mmol of maleic anhydride, and the reaction was conducted under a nitrogen atmosphere. Stirring for a period of time dissolved to obtain a varnish. Ηinh of the polyamic acid in the obtained varnish was 0.78 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 1) and (FIG. 1).
[0094]
Comparative Example 3
A polyimide film was obtained in the same manner as in Comparative Example 2 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 1).
[0095]
Comparative Example 4
A varnish was prepared in the same manner as in Example 1 except that methanol was not used. As a result, 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene obtained in Synthesis Example 1 was obtained. When 0.67 mmol was charged and stirring was performed in a nitrogen atmosphere, the viscosity increased remarkably in a short time and stirring became impossible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0096]
Example 9
Except for using 1,4,5-triaminoanthraquinone instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene, the same procedure as in Example 1 was carried out. A varnish was obtained. Ηinh of the polyamic acid in the obtained varnish was 1.15 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 1) and (FIG. 1).
[0097]
Example 10
A polyimide film was obtained in the same manner as in Example 9 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 1).
[0098]
Example 11
A polyimide film was obtained in the same manner as in Example 9 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 1).
[0099]
Example 12
Except for using 1,4,5-triaminoanthraquinone instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene, the same procedure as in Example 4 was carried out. A varnish was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.62 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0100]
Example 13
A polyimide film was obtained in the same manner as in Example 12 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 2).
[0101]
Example 14
Except for using 1,4,5-triaminoanthraquinone instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene, the same procedure as in Example 6 was carried out. A varnish was obtained. The polyamic acid ηinh in the obtained varnish was 0.60 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0102]
Example 15
A polyimide film was obtained in the same manner as in Example 14 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 2).
[0103]
Example 16
A varnish of the present invention was obtained in the same manner as in Example 9 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.15 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0104]
Comparative Example 5
A varnish was prepared in the same manner as in Example 9 except that methanol was not used, and 0.67 mmol of 1,4,5-triaminoanthraquinone was charged and the viscosity was reduced in a short time when stirred in a nitrogen atmosphere. Increased significantly and stirring was not possible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0105]
Example 17
The present invention was carried out in the same manner as in Example 1 except that 3,4,4′-triaminodiphenyl ether was used instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish was obtained. Ηinh of the polyamic acid in the obtained varnish was 1.14 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2) and (FIG. 1).
[0106]
Example 18
A polyimide film was obtained in the same manner as in Example 17 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 2).
[0107]
Example 19
A polyimide film was obtained in the same manner as in Example 17 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 2).
[0108]
Example 20
The present invention was carried out in the same manner as in Example 4 except that 3,4,4′-triaminodiphenyl ether was used in place of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.62 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0109]
Example 21
A polyimide film was obtained in the same manner as in Example 20 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 2).
[0110]
Example 22
The present invention was carried out in the same manner as in Example 6 except that 3,4,4′-triaminodiphenyl ether was used instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.61 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0111]
Example 23
A polyimide film was obtained in the same manner as in Example 22 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 2).
[0112]
Example 24
A varnish of the present invention was obtained in the same manner as in Example 17 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.15 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 2).
[0113]
Comparative Example 6
A varnish was prepared in the same manner as in Example 17 except that methanol was not used. When 0.67 mmol of 3,4,4′-triaminodiphenyl ether was charged and stirred in a nitrogen atmosphere, the varnish was prepared in a short time. Viscosity increased remarkably and stirring became impossible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0114]
Example 25
A varnish of the present invention was obtained in the same manner as in Example 1 except that melamine was used instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. Ηinh of the polyamic acid in the obtained varnish was 1.12 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3) and (FIG. 1).
[0115]
Example 26
A polyimide film was obtained in the same manner as in Example 25 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 3).
[0116]
Example 27
A polyimide film was obtained in the same manner as in Example 25 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 3).
[0117]
Example 28
A varnish of the present invention was obtained in the same manner as in Example 4 except that melamine was used instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. Ηinh of the polyamic acid in the obtained varnish was 0.63 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3).
[0118]
Example 29
A polyimide film was obtained in the same manner as in Example 28 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 3).
[0119]
Example 30
A varnish of the present invention was obtained in the same manner as in Example 6 except that melamine was used instead of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The polyamic acid ηinh in the obtained varnish was 0.60 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3).
[0120]
Example 31
A polyimide film was obtained in the same manner as in Example 30 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 3).
[0121]
Example 32
A varnish of the present invention was obtained in the same manner as in Example 25 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.13 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3).
[0122]
Comparative Example 7
A varnish was prepared in the same manner as in Example 25 except that methanol was not used. When 0.67 mmol of melamine was charged and stirred in a nitrogen atmosphere, the viscosity increased remarkably in a short time, and stirring was impossible. It was. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0123]
Example 33
The same procedure as in Example 1 except that 0.53 mmol of 3,3′-diaminobenzidine was used instead of 0.67 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 1.11 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3) and (FIG. 1).
[0124]
Example 34
A polyimide film was obtained in the same manner as in Example 33 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 3).
[0125]
Example 35
A polyimide film was obtained in the same manner as in Example 33 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 3).
[0126]
Example 36
Example 3 was repeated except that 2.5 mmol of 3,3′-diaminobenzidine was used instead of 3.3 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.63 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3).
[0127]
Example 37
A polyimide film was obtained in the same manner as in Example 36 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 3).
[0128]
Example 38
The same procedure as in Example 6 was conducted except that 5.00 mmol of 3,3′-diaminobenzidine was used instead of 6.67 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene. The varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.61 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 3).
[0129]
Example 39
A polyimide film was obtained in the same manner as in Example 38 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 4).
[0130]
Example 40
A varnish of the present invention was obtained in the same manner as in Example 33 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.16 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 4).
[0131]
Comparative Example 8
A varnish was prepared in the same manner as in Example 29 except that methanol was not used. When 0.50 mmol of 3,3′-diaminobenzidine was charged and stirred in a nitrogen atmosphere, the viscosity was remarkably short. Ascending and stirring became impossible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0132]
Comparative Example 9
A polyamic acid varnish was prepared according to Example 1 described in JP-B-40-12846. That is, first, dimethylformamide was placed in a flask equipped with a thermometer and a stirrer, and the reactor was set in ice water and stirred in order to keep the internal temperature of the reactor at 20 ° C. or lower. Next, 100 mmol of pyromellitic dianhydride, 92.3 mmol of 4,4′-diaminodiphenylpropane, and 0.15 mmol of 3,3′-diaminobenzidine were gradually added into the dimethylformamide solvent while paying attention to the rise in the solution temperature. Further, when dimethylformamide was added and stirred so that the polyamic acid concentration was 20% by weight, the viscosity increased remarkably in a short time, and stirring was impossible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0133]
Example 41
Other than using 0.53 mmol of 3,3 ′, 4,4′-tetraaminodiphenyl ether instead of 0.67 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene In the same manner as in Example 1, a varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 1.13 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 4) and (FIG. 1).
[0134]
Example 42
A polyimide film was obtained in the same manner as in Example 41 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 4).
[0135]
Example 43
A polyimide film was obtained in the same manner as in Example 41 except that the curing temperature was 230 ° C. Each evaluation result is shown in (Table 4).
[0136]
Example 44
Other than using 2.5 mmol of 3,3 ′, 4,4′-tetraaminodiphenyl ether instead of 3.3 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene In the same manner as in Example 4, a varnish of the present invention was obtained. The polyamic acid ηinh in the obtained varnish was 0.66 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 4).
[0137]
Example 45
A polyimide film was obtained in the same manner as in Example 44 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 4).
[0138]
Example 46
Other than using 5.00 mmol of 3,3 ′, 4,4′-tetraaminodiphenyl ether instead of 6.67 mmol of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene In the same manner as in Example 6, a varnish of the present invention was obtained. Ηinh of the polyamic acid in the obtained varnish was 0.61 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 4).
[0139]
Example 47
A polyimide film was obtained in the same manner as in Example 46 except that the curing temperature was 300 ° C. Each evaluation result is shown in (Table 4).
[0140]
Example 48
A varnish of the present invention was obtained in the same manner as in Example 41 except that 2 mmol of water was used instead of 2 mmol of methanol. Ηinh of the polyamic acid in the obtained varnish was 1.14 dl / g. A polyimide film was obtained in the same manner as Example 1. Each evaluation result is shown in (Table 4).
[0141]
Comparative Example 10
When varnish was prepared in the same manner as in Example 41 except that methanol was not used, 0.50 mmol of 3,3 ′, 4,4′-tetraaminodiphenyl ether was charged and stirred in a nitrogen atmosphere. The viscosity increased remarkably in a short time, and stirring became impossible. It was thought that the polyamic acid was crosslinked, and the reaction mass was gelled in a jelly form.
[0142]
Comparative Example 11
The same amount of 1,3,5-tris (1- (4-aminophenyl) -1-methylethyl) benzene used was 0.67 mmol, and methanol was not used. Obtained. The polyamic acid ηinh in the obtained varnish was 0.60 dl / g. Each evaluation result of the polyimide film obtained in the same manner as in Example 1 is shown in (Table 4) and (FIG. 1). Since the obtained polyimide film has a small amount of triamine used and does not have a sufficient cross-linked structure, it can be seen that it stretches significantly above Tg and does not retain its shape.
[0143]
[Table 1]

[0144]
[Table 2]

[0145]
[Table 3]

[0146]
[Table 4]

[0147]
【The invention's effect】
In the varnish of the present invention, since the polyamic acid whose molecular terminal is a dicarboxylic acid or diester is a straight chain having no cross-linking site, it is handled in the same manner as ordinary polyamic acid varnish, that is, casting, casting, etc. Furthermore, since a crosslinked structure is formed by reacting with a compound having 3 or 4 amino groups simultaneously with imidization by a normal heat treatment, a crosslinked polyimide is obtained according to a conventionally known linear polyimide production condition. I can do it.
The cross-linked polyimide obtained by heat-treating the varnish of the present invention has a higher decomposition temperature than the case where other cross-linking groups are used because the bond generated by cross-linking is an imide bond. Moreover, it has high heat resistance and chemical resistance compared with a linear polyimide by bridge | crosslinking.
[Brief description of the drawings]
[Figure 1] Tensile elongation measurement results of polyimide film

Claims (3)

Any one selected from a compound represented by the following formula (2), a compound represented by the following formula (5), a compound represented by the following formula (7), and a compound represented by the following formula (12) compounds having a seed 3 or 4 amino groups and a molecular end, Ri dicarboxylic acid or an ester thereof der represented by the formula (1-a) or (1-b), and the following formula (13) varnish comprising a polyamic acid that have a repeating structure represented.

(Here, R ₁ in the formulas (1-a) and (1-b) represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or an aromatic group.)

(Here, n is 3, and R ₂ represents a trivalent group represented by the following formula (3).)

(Here, R ₃ represents a divalent group represented by the following formula (4).)

(Here, R ₄ is —NH ₂ or —H, and R ₅ represents a carbonyl group.)

(Here, R ₆ represents an amino group or a monovalent group of a hydrogen atom, R ₇ represents an amino group, and R ₈ represents a direct bond.)

(Here, R ₁₀ represents a trivalent group represented by N.)

(Here, X represents a divalent aromatic group represented by the following formula (14), and Y represents a tetravalent aromatic group selected from the following formula (16).)

(Here, R ₁₁ in the formula (14) is independent and represents a divalent group represented by the following formula (15), and the substitution position on the benzene ring is p-position or m-position.)

Crosslinked polyimide obtained by imidizing claim 1 Symbol placement of varnish. The method for producing a crosslinked polyimide according to claim 2 , wherein the imidization method is by heat treatment, and the heat treatment temperature is 300 ° C or lower.

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