イソタキシカルポリプロピレン の構造力学相図
Claudio De Rosa1, Finizia Auriemma
1Dipartimento di Chimica, Università di Napoli "Federico II", Complesso Monte Sant'Angelo, Via Cintia, 80126 Napoli, Italy.
Journal of the American Chemical Society
|August 24, 2006
まとめ
伸縮性イソタクティックポリプロピレンは,その結晶形をメソフェーズに変換し,高い柔軟性と弾力性を可能にします. この研究は,ステレオ規則性,変形,および多形安定性に関する相図を詳細に説明します.
科学分野:
- ポリマーサイエンスの科学
- マテリアルサイエンス 材料科学
- クリスタログラフィーです.
背景:
- アイソタクティックポリプロピレン (iPP) は,アルファとガンマ相が一般的に観察されるポリモルフィズムを示します.
- メタロセンの触媒は,iPPのステレオレギュラリティに影響を与え,その結晶構造に影響を与えます.
- プラスチックの変形は,半結晶ポリマーの相変換を誘導することができます.
研究 の 目的:
- プラスチックの変形過程におけるイソタクティックポリプロピレンの多形変異を調査する.
- これらの変換におけるステレオレギュラリティとメタルロセンの触媒の役割を理解する.
- ステレオレギュラリティと変形に基づいたiPPの相図を作成する.
主な方法:
- 異なるステレオレギュラリティのイソタクティックポリプロピレンサンプルをメタルロセネ触媒を用いて準備する.
- プラスチックの変形を誘発するための機械的試験 (伸縮) です.
- X線 difraktion (暗示) などの技術を用いた結晶相変換の分析.
主要な成果:
- アルファまたはガンマ結晶の形を含む未拉伸のiPPサンプルが,拉伸するとメソモルフィック・フェーズに変化する.
- メソフェーズ形成は,さらなる変形を容易にし,高ストレスを引き起こす.
- この変換は,柔軟性と弾力性の特性を高めます.
結論:
- メソモルフィック相は,高い変形性とiPPのユニークな弾性特性を達成するために不可欠です.
- ステレオレギュラリティと変形の関数として,異なる多形形の安定領域を図示する相図が開発されました.
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