JPH0150276B2 - - Google Patents
Info
- Publication number
- JPH0150276B2 JPH0150276B2 JP56209650A JP20965081A JPH0150276B2 JP H0150276 B2 JPH0150276 B2 JP H0150276B2 JP 56209650 A JP56209650 A JP 56209650A JP 20965081 A JP20965081 A JP 20965081A JP H0150276 B2 JPH0150276 B2 JP H0150276B2
- Authority
- JP
- Japan
- Prior art keywords
- pitch
- raw material
- temperature
- precursor
- carbonization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000002994 raw material Substances 0.000 claims description 30
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 21
- 239000004917 carbon fiber Substances 0.000 claims description 21
- 238000010438 heat treatment Methods 0.000 claims description 17
- 239000002243 precursor Substances 0.000 claims description 17
- 238000003763 carbonization Methods 0.000 claims description 14
- 238000011282 treatment Methods 0.000 claims description 13
- 238000005087 graphitization Methods 0.000 claims description 9
- 239000003245 coal Substances 0.000 claims description 8
- 238000002074 melt spinning Methods 0.000 claims description 7
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 7
- 150000004678 hydrides Chemical class 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 150000004945 aromatic hydrocarbons Chemical class 0.000 claims description 4
- 239000011295 pitch Substances 0.000 description 63
- SMWDFEZZVXVKRB-UHFFFAOYSA-N Quinoline Chemical compound N1=CC=CC2=CC=CC=C21 SMWDFEZZVXVKRB-UHFFFAOYSA-N 0.000 description 21
- MWPLVEDNUUSJAV-UHFFFAOYSA-N anthracene Chemical compound C1=CC=CC2=CC3=CC=CC=C3C=C21 MWPLVEDNUUSJAV-UHFFFAOYSA-N 0.000 description 10
- 238000000034 method Methods 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- CXWXQJXEFPUFDZ-UHFFFAOYSA-N tetralin Chemical compound C1=CC=C2CCCCC2=C1 CXWXQJXEFPUFDZ-UHFFFAOYSA-N 0.000 description 6
- 208000012886 Vertigo Diseases 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 239000011302 mesophase pitch Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 238000009987 spinning Methods 0.000 description 5
- 239000000835 fiber Substances 0.000 description 4
- 239000011261 inert gas Substances 0.000 description 4
- 239000004973 liquid crystal related substance Substances 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 239000012298 atmosphere Substances 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 229920002239 polyacrylonitrile Polymers 0.000 description 3
- 238000009423 ventilation Methods 0.000 description 3
- NHCREQREVZBOCH-UHFFFAOYSA-N 1-methyl-1,2,3,4,4a,5,6,7,8,8a-decahydronaphthalene Chemical compound C1CCCC2C(C)CCCC21 NHCREQREVZBOCH-UHFFFAOYSA-N 0.000 description 2
- YBYIRNPNPLQARY-UHFFFAOYSA-N 1H-indene Chemical compound C1=CC=C2CC=CC2=C1 YBYIRNPNPLQARY-UHFFFAOYSA-N 0.000 description 2
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 description 2
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 2
- 125000003118 aryl group Chemical group 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- -1 decahydrobiphenyl Chemical compound 0.000 description 2
- NNBZCPXTIHJBJL-UHFFFAOYSA-N decalin Chemical compound C1CCCC2CCCCC21 NNBZCPXTIHJBJL-UHFFFAOYSA-N 0.000 description 2
- XXPBFNVKTVJZKF-UHFFFAOYSA-N dihydrophenanthrene Natural products C1=CC=C2CCC3=CC=CC=C3C2=C1 XXPBFNVKTVJZKF-UHFFFAOYSA-N 0.000 description 2
- ZUOUZKKEUPVFJK-UHFFFAOYSA-N diphenyl Chemical compound C1=CC=CC=C1C1=CC=CC=C1 ZUOUZKKEUPVFJK-UHFFFAOYSA-N 0.000 description 2
- PQNFLJBBNBOBRQ-UHFFFAOYSA-N indane Chemical compound C1=CC=C2CCCC2=C1 PQNFLJBBNBOBRQ-UHFFFAOYSA-N 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- YNPNZTXNASCQKK-UHFFFAOYSA-N phenanthrene Chemical compound C1=CC=C2C3=CC=CC=C3C=CC2=C1 YNPNZTXNASCQKK-UHFFFAOYSA-N 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- BDAGIAXQQBRORQ-UHFFFAOYSA-N 1,2,3,3a,4,5-hexahydroacenaphthylene Chemical compound C1CCC2CCC3=CC=CC1=C32 BDAGIAXQQBRORQ-UHFFFAOYSA-N 0.000 description 1
- ARPANWHHRGVXBN-UHFFFAOYSA-N 1,2,3,4,4a,10-hexahydroanthracene Chemical compound C1=CC=C2CC(CCCC3)C3=CC2=C1 ARPANWHHRGVXBN-UHFFFAOYSA-N 0.000 description 1
- GNMCGMFNBARSIY-UHFFFAOYSA-N 1,2,3,4,4a,4b,5,6,7,8,8a,9,10,10a-tetradecahydrophenanthrene Chemical compound C1CCCC2C3CCCCC3CCC21 GNMCGMFNBARSIY-UHFFFAOYSA-N 0.000 description 1
- JSGPEEFAPXBVCG-UHFFFAOYSA-N 1,2,3,4,4a,4b,5,6,7,8,8a,9-dodecahydrophenanthrene Chemical compound C1CCCC2C3CCCCC3CC=C21 JSGPEEFAPXBVCG-UHFFFAOYSA-N 0.000 description 1
- PJDWNSYGMXODTB-UHFFFAOYSA-N 1,2,3,4,4a,4b,5,6-octahydrophenanthrene Chemical compound C1=CCCC2C(CCCC3)C3=CC=C21 PJDWNSYGMXODTB-UHFFFAOYSA-N 0.000 description 1
- MPUIANDHWHNPJY-UHFFFAOYSA-N 1,2,3,4,4a,4b-hexahydrophenanthrene Chemical compound C1=CC=CC2C(CCCC3)C3=CC=C21 MPUIANDHWHNPJY-UHFFFAOYSA-N 0.000 description 1
- VTIBBOHXBURHMD-UHFFFAOYSA-N 1,2,3,4,4a,5,10,10a-octahydroanthracene Chemical compound C1=CCC2CC(CCCC3)C3=CC2=C1 VTIBBOHXBURHMD-UHFFFAOYSA-N 0.000 description 1
- GVJFFQYXVOJXFI-UHFFFAOYSA-N 1,2,3,4,4a,5,6,7,8,8a,9,9a,10,10a-tetradecahydroanthracene Chemical compound C1C2CCCCC2CC2C1CCCC2 GVJFFQYXVOJXFI-UHFFFAOYSA-N 0.000 description 1
- SJXINMCGKMERBY-UHFFFAOYSA-N 1,2,3,4,4a,5,6,7,8,8a,9,9a-dodecahydroanthracene Chemical compound C1=C2CCCCC2CC2C1CCCC2 SJXINMCGKMERBY-UHFFFAOYSA-N 0.000 description 1
- PUNXVEAWLAVABA-UHFFFAOYSA-N 1,2,3,4-tetrahydroanthracene;1,2,5,6-tetrahydroanthracene Chemical compound C1=CC=C2C=C(CCCC3)C3=CC2=C1.C1=CCCC2=C1C=C1CCC=CC1=C2 PUNXVEAWLAVABA-UHFFFAOYSA-N 0.000 description 1
- UXNCDAQNSQBHEN-UHFFFAOYSA-N 1,2,3,4-tetrahydrophenanthrene Chemical compound C1=CC2=CC=CC=C2C2=C1CCCC2 UXNCDAQNSQBHEN-UHFFFAOYSA-N 0.000 description 1
- AXLCNVVQTVIXDG-UHFFFAOYSA-N 1-ethyl-1,2,3,4-tetrahydronaphthalene Chemical compound C1=CC=C2C(CC)CCCC2=C1 AXLCNVVQTVIXDG-UHFFFAOYSA-N 0.000 description 1
- APBBTKKLSNPFDP-UHFFFAOYSA-N 1-methyl-1,2,3,4-tetrahydronaphthalene Chemical compound C1=CC=C2C(C)CCCC2=C1 APBBTKKLSNPFDP-UHFFFAOYSA-N 0.000 description 1
- XSRADQOBRZHEOB-UHFFFAOYSA-N 1-methyl-1,2-dihydroacenaphthylene Chemical compound C1=CC(C(C)C2)=C3C2=CC=CC3=C1 XSRADQOBRZHEOB-UHFFFAOYSA-N 0.000 description 1
- LRCMZPVVFRECQR-UHFFFAOYSA-N 1-propan-2-yl-1,2,3,4-tetrahydronaphthalene Chemical compound C1=CC=C2C(C(C)C)CCCC2=C1 LRCMZPVVFRECQR-UHFFFAOYSA-N 0.000 description 1
- ABIPNDAVRBMCHV-UHFFFAOYSA-N 4,4-dimethyl-2,3-dihydro-1h-naphthalene Chemical compound C1=CC=C2C(C)(C)CCCC2=C1 ABIPNDAVRBMCHV-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- XBDYBAVJXHJMNQ-UHFFFAOYSA-N Tetrahydroanthracene Natural products C1=CC=C2C=C(CCCC3)C3=CC2=C1 XBDYBAVJXHJMNQ-UHFFFAOYSA-N 0.000 description 1
- CWRYPZZKDGJXCA-UHFFFAOYSA-N acenaphthene Chemical compound C1=CC(CC2)=C3C2=CC=CC3=C1 CWRYPZZKDGJXCA-UHFFFAOYSA-N 0.000 description 1
- 125000004054 acenaphthylenyl group Chemical group C1(=CC2=CC=CC3=CC=CC1=C23)* 0.000 description 1
- HXGDTGSAIMULJN-UHFFFAOYSA-N acetnaphthylene Natural products C1=CC(C=C2)=C3C2=CC=CC3=C1 HXGDTGSAIMULJN-UHFFFAOYSA-N 0.000 description 1
- 239000004480 active ingredient Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000005273 aeration Methods 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 235000010290 biphenyl Nutrition 0.000 description 1
- 239000004305 biphenyl Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 230000005587 bubbling Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 238000007380 fibre production Methods 0.000 description 1
- 229910052811 halogen oxide Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000011301 petroleum pitch Substances 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 150000003248 quinolines Chemical class 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- PXXNTAGJWPJAGM-UHFFFAOYSA-N vertaline Natural products C1C2C=3C=C(OC)C(OC)=CC=3OC(C=C3)=CC=C3CCC(=O)OC1CC1N2CCCC1 PXXNTAGJWPJAGM-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Working-Up Tar And Pitch (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Inorganic Fibers (AREA)
Description
本発明は炭素繊維用原料としての優れた性能を
有するピツチの製造方法に関する。
現在、炭素繊維は主にポリアクリロニトリルを
原料として製造されている。しかしながらポリア
クリロニトリルを原料とした場合、原料が高価で
あり、また加熱炭化時において繊維状の原料がく
ずれ易く、さらに炭化収率も悪いという欠点があ
る。
近年、この点に着目して安価なピツチを原料と
して炭素繊維を製造する方法が数多く報告されて
いる。しかしながら、ピツチを原料として得られ
る炭素繊維は、ポリアクリロニトリル系炭素繊維
に比べ、強度が劣るという問題がある。
最近になつて、市販の石油ピツチを熱処理して
メソ相（mesophase）と呼ばれる光学的異方性の
液晶を含有するピツチを得、このメソ相を含有す
るピツチを前駆体ピツチ（以後、溶融紡糸時にお
けるピツチを前駆体ピツチと呼ぶ）として用い、
この前駆体ピツチを溶融紡糸した後、不融化し、
次いで炭化あるいは更に黒鉛化することにより、
弾性率および強度が向上した炭素繊維が得られる
ことが報告された（特開昭49−19127号）。
しかしながら、ピツチが液晶を形成し得るか否
かは種々の要因により決まるものであり、また液
晶の構造や軟化点、粘度等の物件は原料ピツチに
大きく依存するものである。前記特開昭49−
19127号はメソ相を含有するピツチ（以後、メソ
相ピツチと略記する）の調製法に関するものであ
つて、良質のメソ相ピツチを形成するための原料
ピツチについては何ら言及していない。前記した
ように、良質のメソ相ピツチは原料ピツチに大き
く依存するものであり、最適な原料ピツチを見出
すことができれば弾性率および強度がさらに優れ
た炭素繊維を製造することが可能となる。それ
故、この最適の原料ピツチを見出すことが当該技
術分野の重要な課題である。
例えば、市販の石油ピツチは加熱処理して前駆
体ピツチを調製する段階でキノリンに不溶な高分
子量成分が生成する。すなわち、熱処理の際に熱
分解と重縮合反応が併発し、低分子量成分は徐々
に高分子量化し、キノリンに不溶の高分子量成分
となり、また同時に高分子量成分はさらに高分子
量化する。これに併つてピツチの軟化点も上昇す
る。このキノリン不溶分の存在と高い軟化点は溶
融紡糸の段階で悪影響を及ぼす。すなわち、前駆
体ピツチを溶融紡糸するためには、前駆体ピツチ
が紡糸可能な粘度になるまで紡糸温度を上げるこ
とが必要であつて、前駆体ピツチの軟化点が余り
にも高過ぎれば、紡糸温度も当然高くせざるを得
ず、その結果、キノリン不溶分は一層高分子量化
すると共にピツチの熱分解が起こり軽質ガスが発
生し、均一な前駆体ピツチとはなり得ず、紡糸す
ることが事実上不可能となる。
このように前駆体ピツチは、比較的低い軟化点
と紡糸するために適当な粘度を持つていなければ
ならない。また、紡糸時さらには炭化時に揮発性
成分を実質的に含有するものであつてはならな
い。
このため、生成したキノリン不溶分を加圧過
や溶剤分別等の手段により除去することにより炭
素繊維製造用前駆体ピツチを調製することが行わ
れている（特開昭47−9804号、同50−142820号、
同55−1342号、同55−5954号）。しかしながら、
これらの手段を用いた場合には処理装置の複雑化
および処理費用の増大を招き、経済的観点から好
ましいものではない。
もし、原料ピツチとして優れた性能を有するピ
ツチを用いることにより、メソ相化の加熱段階で
キノリン不溶分となる高分子量成分の生成を抑制
することができれば最も好ましいものである。
本発明者らは、これらの課題について鋭意研究
した結果、本発明を完成したものである。すなわ
ち、本発明者らは、前駆体ピツチを調製する段階
で高分子量成分の生成を抑制し、最適な粘度を有
し、また炭化初期の段階では芳香族平面が秩序だ
つて配列をし易い組成を持つことができる性能の
優れた原料ピツチを見出したものである。換言す
れば、本発明は軟化点が比較的低く保持され、か
つメソ相を容易に形成するような原料ピツチの製
造方法を提供するものである。
以下本発明を詳述する。
本発明は原料ピツチを熱処理して、メソ相
（mesophase）と呼ばれる光学的異方性の液晶を
含有するピツチを得、このメソ相を含有するピツ
チを前駆体ピツチとして用い、この前駆体ピツチ
を溶融紡糸した後、不融化し、次いで炭化あるい
は更に黒鉛化することにより、弾性率および強度
が向上した炭素繊維を製造するものである。
本発明に係る原料ピツチは、(1)石炭液化ピツチ
と(2)２環もしくは３環の芳香族炭化水素の核水素
化物を特定の割合で混合し、かつ特定の条件下に
加熱処理することにより得られる。
上記の成分(1)と成分(2)の混合割合は、成分(1)：
成分(2)が容量比で１：0.1〜２、好ましくは１：
0.2〜1.5であることが非要である。加熱処理温度
としては370〜480℃、好ましくは390〜460℃の範
囲内の温度で行う。加熱処理温度が370℃よりも
低いと反応の進行が遅く、長時間を要するため不
経済である。また480℃よりも高い温度で熱処理
を行うとコーキング等の問題が生じ、好ましくな
い。加熱処理時間は、加熱処理温度との兼ね合い
で決められるものであり、低温の場合は長時間、
高温の場合は短時間行う。通常は、15分〜20時
間、好ましくは30分〜10時間の範囲内の処理時間
を採用することができる。圧力に関しては任意の
圧力下で実施し得るが、原料中の有効成分が末反
応のまま実質的に系外に留出しない圧力が好まし
く、具体的には２〜50Kg／cm2・Ｇ、好ましくは５
〜30Kg／cm2・Ｇが採用される。
熱処理を行つた後、必要であれば蒸留等の操作
により軽質分を除去することも好ましく採用され
る。
本発明において使用する石炭液化ピツチとは、
公知の石炭液化法により各種の石炭類を触媒の存
在下あるいは不存在下に、通常10〜500Kg／cm2の
水素加圧下、炭化水素系溶媒中で温度350〜500℃
で処理して得られる解重合物のうち沸点200℃以
上のピツチ状物質という。
本発明において使用する２環もしくは３環の芳
香族系炭化水素の核水素化物とは、ナフタリン、
インデン、ビフエニル、アセナフチレン、アンス
ラセン、フエナンスレンおよびこれらの炭素数１
〜３のアルキル置換体の核水素化物である。具体
的には、デカリン、メチルデカリン、テトラリ
ン、メチルテトラリン、ジメチルテトラリン、エ
チルテトラリン、イソプロピルテトラリン、イン
ダン、デカヒドロビフエニル、アセナフテン、メ
チルアセナフテン、テトラヒドロアセナフテン、
ジヒドロアンスラセン、メチルヒドロアンスラセ
ン、ジメチルヒドロアンスラセン、エチルヒドロ
アンスラセン、テトラヒドロアンスラセン、ヘキ
サヒドロアンスラセン、オクタヒドロアンスラセ
ン、ドデカヒドロアンスラセン、テトラデカヒド
ロアンスラセン、ジヒドロフエナンスレン、メチ
ルジヒドロフエナンスレン、テトラヒドロフエナ
ンスレン、ヘキサヒドロフエナンスレン、オクタ
ヒドロフエナンスレン、ドデカヒドロフエナンス
レンおよびテトラデカヒドロフエナンスレンを挙
げることができる。特に２環または３環の縮合環
状芳香族系炭化水素の核水素化物が好ましい。本
発明においては、これらの２種以上の混合物とし
て用いることもできる。
かくして得られる本発明よりなる原料ピツチを
用いることにより、加熱処理してメソ相化を行つ
た際、キノリン不溶分である高分子量成分の生成
が抑制されると同時にピツチの軟化点の上昇を防
ぐことができ、さらに芳香族平面が秩序だつて配
列し易い組成を持つた良好な前駆体ピツチとな
る。この結果、弾性率および強度がきわめて優れ
た炭素繊維を得ることができる。
本発明により得られる原料ピツチを用いて炭素
繊維を製造する方法は公知の方法を採用すること
ができる。すなわち、原料ピツチを加熱処理して
メソ相化を行い、得られる前駆体ピツチを溶融紡
糸した後、不融化処理および炭化あるいはさらに
黒鉛化処理を行つて炭素繊維を製造する。
原料ピツチを加熱処理し、メソ相化を行つて前
駆体ピツチを得る段階での反応は、通常、温度
340〜450℃、好ましくは370〜420℃で、常圧ある
いは減圧下に窒素等の不活性ガスを通気すること
によつて行われる。この時の加熱処理時間は、温
度、不活性ガスの通気量等の条件により任意に行
い得るものであるが、通常、１〜50時間、好まし
くは３〜20時間で行う。不活性ガスの通気量は
0.7〜5.0scfh／1bピツチが好ましい。
前駆体ピツチを溶融紡糸する方法としては、押
出法、遠心法、霧吹法等の公知の方法を用いるこ
とができる。
溶融紡糸されて得られるピツチ繊維は、次に酸
化性ガス雰囲気下で不融化処理が施される。酸化
性ガスとしては、通常、酸素、オゾン、空気、窒
素酸化物、ハロゲン、亜硫酸ガス等の酸化性ガス
を１種あるいは２種以上用いる。この不融化処理
は、被処理体である溶融紡糸されたピツチ繊維が
軟化変形しない温度条件下で実施される。例えば
20〜360℃、好ましくは20〜300℃の温度が採用さ
れる。また処理時間は通常、５分〜10時間であ
る。
不融化処理されたピツチ繊維は、次に不活性ガ
ス雰囲気下で炭化あるいは更に黒鉛化を行い、炭
素繊維を得る。炭化は通常、温度800〜2500℃で
行う。一般には炭化に要する処理時間は0.5分〜
10時間である。さらに黒鉛化を行う場合には、温
度2500〜3500℃で通常１秒〜１時間行う。
また、不融化、炭化あるいは黒鉛化処理の際、
必要であれば収縮や変形等を防止する目的で、被
処理体に若干の荷重あるいは張力をかけておくこ
ともできる。
以下に実施例および比較例をあげて本発明を具
体的に説明するが、本発明はこれらに制限される
ものではない。
実施例 １
石炭液化ピツチ（性状を第１表に示す）50容量
部にテトラリン50容量部を混合し、圧力20Kg／
cm2・Ｇ、温度410℃にて１時間熱処理した。この
熱処理油を250℃／1.0mmHgで蒸留して軽質分を
留出させ原料ピツチを得た。このピツチの軟化点
は153℃、キノリン不溶分は10％であり、収率は
53wt％であつた。
次に、この原料ピツチ30gに対し、窒素を600
ml／分で通気しながら撹拌し、温度400℃で５時
間熱処理を行い、軟化点282℃、キノリン不溶分
35wt％、メソ相含量72％のピツチを、45％の収
率で得た。このピツチをノズル径0.3mmφ、Ｌ／
Ｄ＝２の紡糸器を用い335℃で溶融紡糸し、13μ
のピツチ繊維をつくり、さらに下記に示す条件に
て不融化、炭化および黒鉛化処理して炭素繊維を
得た。
Γ不融化条件：空気雰囲気中で、200℃までは３
℃／分、300℃までは１℃／分の昇温速度で加
熱し、300℃で30分間保持。
Γ炭化条件：窒素雰囲気中で、５℃／分で昇温し
1000℃で30分間保持。
Γ黒鉛化条件：アルゴン気流中で、25℃／分の昇
温速度で、2500℃まで加熱処理。
得られた炭素繊維の径は11μであり、引張強度
は240Kg／mm2、ヤング率は38ton／mm2であつた。
The present invention relates to a method for producing pitch, which has excellent performance as a raw material for carbon fibers. Currently, carbon fiber is mainly manufactured using polyacrylonitrile as a raw material. However, when polyacrylonitrile is used as a raw material, the raw material is expensive, the fibrous raw material tends to collapse during heating and carbonization, and the carbonization yield is also poor. In recent years, focusing on this point, many methods have been reported for producing carbon fibers using inexpensive pitch as a raw material. However, carbon fibers obtained using pitch as a raw material have a problem in that their strength is inferior to that of polyacrylonitrile-based carbon fibers. Recently, commercially available petroleum pits have been heat-treated to obtain pits containing optically anisotropic liquid crystals called mesophases, and pitches containing this mesophases have been converted into precursor pits (hereinafter referred to as melt-spun). The pitch at the time is called the precursor pitch),
After melt-spinning this precursor pitch, it is made infusible and
Then, by carbonization or further graphitization,
It was reported that carbon fibers with improved elastic modulus and strength could be obtained (Japanese Patent Application Laid-open No. 19127-1983). However, whether a pitch can form a liquid crystal is determined by various factors, and properties such as the structure, softening point, and viscosity of the liquid crystal greatly depend on the pitch of the raw material. Said Japanese Unexamined Patent Application Publication No. 1973-
No. 19127 relates to a method for preparing pitch containing mesophase (hereinafter abbreviated as mesophase pitch), but does not mention anything about the raw material pitch for forming high quality mesophase pitch. As mentioned above, a high-quality mesophase pitch largely depends on the raw material pitch, and if an optimal raw material pitch can be found, it will be possible to produce carbon fibers with even better elastic modulus and strength. Therefore, finding this optimal raw material pitch is an important challenge in this technical field. For example, when commercially available petroleum pitch is heat-treated to prepare precursor pitch, high molecular weight components that are insoluble in quinoline are generated. That is, during heat treatment, thermal decomposition and polycondensation reactions occur simultaneously, and the low molecular weight components gradually increase in molecular weight to become high molecular weight components that are insoluble in quinoline, and at the same time, the high molecular weight components further increase in molecular weight. At the same time, the softening point of pitch increases. The presence of this quinoline insoluble content and high softening point have an adverse effect on the melt spinning stage. In other words, in order to melt-spun a precursor pitch, it is necessary to raise the spinning temperature until the precursor pitch has a viscosity that allows spinning, and if the softening point of the precursor pitch is too high, the spinning temperature may As a result, the molecular weight of the insoluble quinoline content becomes even higher, and the pitch is thermally decomposed and light gas is generated, making it impossible to form a uniform precursor pitch and making it difficult to spin. becomes impossible. Thus, the precursor pitch must have a relatively low softening point and a suitable viscosity for spinning. Furthermore, it must not substantially contain volatile components during spinning or carbonization. For this reason, precursor pitch for carbon fiber production is prepared by removing the generated quinoline insoluble matter by means such as pressurization and solvent separation (Japanese Patent Application Laid-Open No. 47-9804, 50 −142820,
55-1342, 55-5954). however,
When these means are used, the processing equipment becomes complicated and the processing cost increases, which is not preferable from an economic point of view. It would be most preferable if a pitch having excellent performance could be used as a raw material pitch to suppress the production of high molecular weight components that become quinoline insoluble components during the heating step of mesophase formation. The present inventors have completed the present invention as a result of intensive research into these problems. That is, the present inventors suppressed the formation of high molecular weight components at the stage of preparing the precursor pitch, had an optimal viscosity, and created a composition in which the aromatic planes were easily arranged in an orderly manner at the early stage of carbonization. We have discovered a raw material pitch with excellent performance. In other words, the present invention provides a method for producing a raw material pitch in which the softening point is kept relatively low and the mesophase is easily formed. The present invention will be explained in detail below. In the present invention, a raw material pitch is heat-treated to obtain a pitch containing an optically anisotropic liquid crystal called mesophase, and the pitch containing this mesophase is used as a precursor pitch. After melt-spinning, carbon fibers are made infusible and then carbonized or graphitized to produce carbon fibers with improved elastic modulus and strength. The raw material pitch according to the present invention is prepared by mixing (1) coal liquefied pitch and (2) nuclear hydride of a two- or three-ring aromatic hydrocarbon in a specific ratio, and heat-treating the mixture under specific conditions. It is obtained by The mixing ratio of component (1) and component (2) above is component (1):
Component (2) has a volume ratio of 1:0.1 to 2, preferably 1:
It is not necessary that it be between 0.2 and 1.5. The heat treatment temperature is 370 to 480°C, preferably 390 to 460°C. If the heat treatment temperature is lower than 370°C, the reaction progresses slowly and takes a long time, which is uneconomical. Further, heat treatment at a temperature higher than 480°C causes problems such as caulking, which is not preferable. The heat treatment time is determined based on the heat treatment temperature; if the temperature is low, it will take a long time;
If the temperature is high, do it for a short time. Generally, treatment times within the range of 15 minutes to 20 hours, preferably 30 minutes to 10 hours can be employed. Regarding the pressure, the reaction can be carried out under any desired pressure, but it is preferable to use a pressure at which the active ingredients in the raw materials do not substantially distill out of the system as a final reaction, specifically 2 to 50 Kg/cm 2 ·G, preferably is 5
~30Kg/cm 2・G is adopted. After the heat treatment, it is also preferable to remove light components by distillation or the like, if necessary. The coal liquefaction pit used in the present invention is
By a known coal liquefaction method, various types of coal are heated in a hydrocarbon solvent at a temperature of 350 to 500°C under a hydrogen pressure of usually 10 to 500 kg/cm 2 in the presence or absence of a catalyst.
Among the depolymerized products obtained by processing, it is called a pitch-like substance with a boiling point of 200℃ or higher. The nuclear hydrides of 2- or 3-ring aromatic hydrocarbons used in the present invention include naphthalene,
Indene, biphenyl, acenaphthylene, anthracene, phenanthrene and these with 1 carbon number
It is a nuclear hydride of an alkyl substituted product of ~3. Specifically, decalin, methyldecalin, tetralin, methyltetralin, dimethyltetralin, ethyltetralin, isopropyltetralin, indane, decahydrobiphenyl, acenaphthene, methylacenaphthene, tetrahydroacenaphthene,
Dihydro anthracene, methylhydro anthracene, dimethylhydro anthracene, ethylhydro anthracene, tetrahydro anthracene, hexahydro anthracene, octahydro anthracene, dodecahydro anthracene, tetradecahydro anthracene, dihydrophenanthrene, methyl Mention may be made of dihydrophenanthrene, tetrahydrophenanthrene, hexahydrophenanthrene, octahydrophenanthrene, dodecahydrophenanthrene and tetradecahydrophenanthrene. In particular, nuclear hydrides of 2- or 3-ring condensed cyclic aromatic hydrocarbons are preferred. In the present invention, a mixture of two or more of these can also be used. By using the raw material pitch of the present invention thus obtained, when heat-treated to form a mesophase, the production of high molecular weight components that are insoluble in quinoline is suppressed, and at the same time, the softening point of the pitch is prevented from increasing. Furthermore, it becomes a good precursor pitch having a composition in which the aromatic planes are easily arranged in an orderly manner. As a result, carbon fibers with extremely excellent elastic modulus and strength can be obtained. A known method can be used to produce carbon fiber using the raw material pitch obtained according to the present invention. That is, a raw material pitch is heat-treated to form a mesophase, the resulting precursor pitch is melt-spun, and then subjected to infusibility treatment and carbonization or further graphitization treatment to produce carbon fibers. The reaction at the stage of heat-treating the raw material pitch to convert it into a mesophase to obtain the precursor pitch is usually carried out at a temperature
The reaction is carried out at a temperature of 340 to 450°C, preferably 370 to 420°C, by bubbling an inert gas such as nitrogen under normal pressure or reduced pressure. The heat treatment time at this time can be arbitrarily determined depending on conditions such as temperature and amount of inert gas aeration, but it is usually carried out for 1 to 50 hours, preferably 3 to 20 hours. The amount of inert gas ventilation is
A pitch of 0.7 to 5.0 scfh/1b is preferred. As a method for melt-spinning the precursor pitch, known methods such as an extrusion method, a centrifugation method, and an atomization method can be used. The pitch fiber obtained by melt spinning is then subjected to an infusible treatment in an oxidizing gas atmosphere. As the oxidizing gas, one or more of oxidizing gases such as oxygen, ozone, air, nitrogen oxide, halogen, and sulfur dioxide gas are usually used. This infusibility treatment is carried out under temperature conditions that do not soften or deform the melt-spun pitch fibers to be treated. for example
Temperatures of 20-360°C, preferably 20-300°C are employed. Further, the treatment time is usually 5 minutes to 10 hours. The infusible pitch fibers are then carbonized or further graphitized in an inert gas atmosphere to obtain carbon fibers. Carbonization is usually carried out at a temperature of 800-2500°C. Generally, the processing time required for carbonization is 0.5 minutes ~
It is 10 hours. Further, when graphitization is performed, it is usually carried out at a temperature of 2500 to 3500°C for 1 second to 1 hour. In addition, during infusibility, carbonization or graphitization treatment,
If necessary, a slight load or tension may be applied to the object to be processed in order to prevent shrinkage, deformation, etc. The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Example 1 50 parts by volume of coal liquefaction pitch (properties shown in Table 1) were mixed with 50 parts by volume of tetralin, and the mixture was heated to a pressure of 20 kg/kg.
Heat treatment was performed at cm 2 ·G and a temperature of 410°C for 1 hour. This heat-treated oil was distilled at 250°C/1.0 mmHg to remove light components and obtain raw material pitch. The softening point of this pitch is 153℃, the quinoline insoluble content is 10%, and the yield is
It was 53wt%. Next, add 600 g of nitrogen to 30 g of this raw material pitch.
Stir with ventilation at a rate of ml/min, heat treat at 400℃ for 5 hours, softening point 282℃, quinoline insoluble content.
Pitch with a mesophase content of 35 wt% and 72% was obtained in a yield of 45%. Set this pitch to a nozzle diameter of 0.3mmφ, L/
Melt-spun at 335℃ using a D=2 spinner to obtain a 13μ
Pitch fibers were prepared, and carbon fibers were obtained by infusibility, carbonization, and graphitization treatment under the conditions shown below. ΓInfusibility conditions: 3 in air atmosphere up to 200℃
℃/min, heat at a heating rate of 1℃/min up to 300℃, and hold at 300℃ for 30 minutes. Γ Carbonization conditions: In a nitrogen atmosphere, temperature was increased at 5°C/min.
Hold at 1000℃ for 30 minutes. Γ Graphitization conditions: Heat treatment in an argon stream at a heating rate of 25°C/min to 2500°C. The diameter of the obtained carbon fiber was 11μ, the tensile strength was 240Kg/mm 2 , and the Young's modulus was 38ton/mm 2 .
【表】
比較例 １
実施例１で使用した石炭液化ピツチ150mlを圧
力15Kg／cm2・Ｇ、温度415℃にて３時間熱処理し
た。この熱処理油を250℃／1.0mmHgで蒸留して
軽質分を留出させ原料ピツチを得た。このピツチ
の軟化点は179℃、キノリン不溶分は15％であり、
収率は60wt％であつた。
次に、このピツチ30gに対し、窒素を600ml／
分で通気しながら撹拌し、温度400℃で５時間熱
処理を行い、軟化点330℃、キノリン不溶分48wt
％、メソ相割合98％のピツチを52％の収率で得
た。このピツチを実施例１と同様の方法で溶融紡
糸、不融化処理、炭化および黒鉛化処理して炭素
繊維を得た。
得られた炭素繊維の径は12μであり、引張強度
は110Kg／mm2、ヤング率は15ton／mm2であつた。
実施例 ２〜８
実施例１で用いた石炭液化ピツチに、第２表に
示される各種の２環もしくは３環の芳香族系炭化
水素の核水素化物を混合し、実施例１に準じた方
法で原料ピツチを得た。その結果を第２表に示
す。
次に、この原料ピツチを実施例１と同様の方法
で熱処理を行ない、メソフエーズピツチを得た。
その結果を第３表に示す。
このメソフエーズピツチを実施例１と同様の方
法で溶融紡糸した後、不融化、炭化および黒鉛化
処理して炭素繊維を得た。その結果を第４表に示
す。[Table] Comparative Example 1 150ml of the coal liquefaction pitch used in Example 1 was heat treated at a pressure of 15Kg/cm 2 ·G and a temperature of 415°C for 3 hours. This heat-treated oil was distilled at 250°C/1.0 mmHg to remove light components and obtain raw material pitch. The softening point of this pitch is 179℃, the quinoline insoluble content is 15%,
The yield was 60wt%. Next, add 600ml/nitrogen to 30g of this pitch.
Stir with ventilation for 5 hours, heat treatment at 400℃ for 5 hours, softening point 330℃, quinoline insoluble content 48wt.
%, and pitch with a mesophase ratio of 98% was obtained in a yield of 52%. This pitch was subjected to melt spinning, infusibility treatment, carbonization and graphitization treatment in the same manner as in Example 1 to obtain carbon fibers. The diameter of the obtained carbon fiber was 12μ, the tensile strength was 110Kg/mm 2 , and the Young's modulus was 15ton/mm 2 . Examples 2 to 8 Nuclear hydrides of various two- or three-ring aromatic hydrocarbons shown in Table 2 were mixed into the coal liquefaction pitch used in Example 1, and the method was carried out according to Example 1. The raw material pitch was obtained. The results are shown in Table 2. Next, this raw material pitch was heat treated in the same manner as in Example 1 to obtain mesophase pitch.
The results are shown in Table 3. This mesophase pitch was melt-spun in the same manner as in Example 1, and then subjected to infusibility, carbonization, and graphitization treatments to obtain carbon fibers. The results are shown in Table 4.
【表】【table】
【表】【table】
Claims (1)
ツチを溶融紡糸した後、不融化処理および炭化あ
るいは更に黒鉛化処理して炭素繊維を製造するに
当り、該原料ピツチが(1)石炭液化ピツチ100容量
部に対し、(2)２環もしくは３環の芳香族系炭化水
素の核水素化物10〜200容量部を添加し、温度370
〜480℃、圧力２〜50Kg／cm2・Ｇにて熱処理して
得られるものであることを特徴とする炭素繊維用
原料ピツチの製造方法。1. When producing carbon fiber by melt-spinning a precursor pitch obtained by heating a raw material pitch, and then subjecting it to infusibility treatment and carbonization or further graphitization treatment, the raw material pitch is (1) coal liquefaction pitch 100 10 to 200 parts by volume of (2) 2- or 3-ring aromatic hydrocarbon nuclear hydride are added to the volume part, and the temperature is 370°C.
A method for producing a raw material pitch for carbon fiber, characterized in that it is obtained by heat treatment at ~480°C and a pressure of 2~50 kg/cm 2 ·G.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20965081A JPS58113289A (en) | 1981-12-28 | 1981-12-28 | Pitch for raw material of carbon fiber |
| GB08232570A GB2110232B (en) | 1981-11-18 | 1982-10-15 | Process for the production of ethane |
| GB08232570A GB2111524B (en) | 1981-11-18 | 1982-11-15 | Starting pitches for carbon fibers |
| US06/441,670 US4460557A (en) | 1981-11-18 | 1982-11-15 | Starting pitches for carbon fibers |
| DE19823242629 DE3242629A1 (en) | 1981-11-18 | 1982-11-18 | INITIAL SPEECH FOR CARBON FIBERS |
| FR8219331A FR2516556B1 (en) | 1981-11-18 | 1982-11-18 | RAW MATERIALS CONSISTING OF PITS FOR THE PREPARATION OF CARBON FIBERS |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20965081A JPS58113289A (en) | 1981-12-28 | 1981-12-28 | Pitch for raw material of carbon fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58113289A JPS58113289A (en) | 1983-07-06 |
| JPH0150276B2 true JPH0150276B2 (en) | 1989-10-27 |
Family
ID=16576308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20965081A Granted JPS58113289A (en) | 1981-11-18 | 1981-12-28 | Pitch for raw material of carbon fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58113289A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2020533471A (en) * | 2017-09-13 | 2020-11-19 | ユニバーシティ オブ ワイオミング | Systems and methods for refining coal into high-value products |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56100895A (en) * | 1980-01-18 | 1981-08-13 | Agency Of Ind Science & Technol | Hydrogenation treatment of heavy bitumen substance |
-
1981
- 1981-12-28 JP JP20965081A patent/JPS58113289A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56100895A (en) * | 1980-01-18 | 1981-08-13 | Agency Of Ind Science & Technol | Hydrogenation treatment of heavy bitumen substance |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58113289A (en) | 1983-07-06 |
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