ポリメリゼーション後の改変により,アタキシ性およびアイソタキシ性ポリアクリロニトリル共ポリマーおよび関連する炭素繊維を合成する.
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PubMedで要約を見る
まとめ
この要約は機械生成です。この研究では,ステレオ制御ポリメリゼーションで合成されたイソタキシ性ポリアクリロニトリル (iPAN) が導入されます. iPAN基の炭素繊維は,従来のPAN繊維と比較して,引力強度とモジュールを大幅に高めています.
科学分野
- ポリマー化学
- 材料科学
- ナノテクノロジー
背景
- ポリアクリロニトリル (PAN) は,炭素繊維 (CF) の90%以上の主要な前体である.
- 従来のPAN合成にはステレオ化学的制御が欠け,その結果,広範囲に分散され,CFの特性に影響を与えます.
- PANの前駆体のステレオ化学は,CFのグラフィティ化と最終的な特性にとって極めて重要です.
研究 の 目的
- 制御されたステレオ化学で同質的なPAN (iPAN) を合成するための新しい方法を開発する.
- iPAN前駆者のステレオ化学が,炭素繊維の性質に及ぼす影響を調査する.
- PANベースの炭素繊維の引力強さとモジュールを改善する.
主な方法
- ルイス酸触媒によるステレオ制御ポリメリゼーションによる2段階のプロセスで, tert-butylacrylamide を同質的 PTBAM (iPTBAM) に変換する.
- iPTBAMをイソタキシ性ポリアクリロニトリル (iPAN-TB) に変換するためのポリメリゼーション後の改変.
- iPAN-TBとコントロールPANを原材料繊維に濡らしてり,その後に高温 (250°Cと1500°C) で加工する.
主要な成果
- 低分散度 (<1. 25) と高同位性 (約. 77% ミリメートルトライアード).
- iPAN- TBでアクリルアミド群をナトリルに変換する割合は最大78%に達した.
- iPAN-TB製の炭素繊維は,加熱した後に,伸縮性を損なうことなく,引力強度がほぼ6倍,モジュールが4倍に増加した.
結論
- iPANのステレオ制御合成は,高度な炭素繊維への経路を提供します.
- iPANベースのCFの強化された機械的性質は,前駆体ステレオ化学の改善に起因する.
- このアプローチは,PANベースの炭素繊維技術に大きな進歩をもたらします.
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