コーディネーションポリメリゼーションにおける分子重量分布の形状の制御とその物理特性への影響
Renee J Sifri1, Omar Padilla-Vélez1, Geoffrey W Coates1
1Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States.
Journal of the American Chemical Society
|December 28, 2019
まとめ
高密度ポリエチレン (HDPE) の分子量分布 (MWD) の形状を制御することは,粘度のようなレオロギー特性に影響しますが,材料の強度には影響しません. これにより,HDPEの性能を損なうことなく,パーソナライズされた加工が可能になります.
科学分野:
- ポリマー化学
- 材料科学
- レオロギー
背景:
- 高密度ポリエチレン (HDPE) は,多用途の物理特性と費用対効果で知られる広く使用されるポリマーです.
- 分子重量と分散はHDPEの特性に影響しますが,分子重量分布 (MWD) の形状の影響は未熟のままです.
研究 の 目的:
- 高密度ポリエチレン (HDPE) の物理的性質に分子量分布 (MWD) の形状がどのように影響するかを調査する.
- ポリメリゼーションの開始を制御することによってMWDの形状効果を研究するための体系的な方法を確立する.
主な方法:
- 精密にMWDの形を制御するために,エチレンの生活調整挿入ポリメリゼーションの時間調節を使用します.
- 複合的な粘度と切断の薄め行動を分析するためにレオロジックテストを実施しました.
- 断裂時のストレスを評価するために,牽引試験を行いました.
主要な成果:
- リオロジカル・テストでは,MWDの傾斜方向 (MWDの反対方向) に基づいて,複雑な粘度と切断の薄れがはっきりと示されました.
- 張力試験では,MWDの歪みは,材料の強さの重要な測定値である破裂時の張力に大きな影響を与えないことが示されました.
結論:
- HDPEのMWDの形は,粘度や切断性薄化などの加工特性に影響を与えるように変更することができます.
- 重要なことは,MWDの形状の変更はHDPEの基本的な材料の強度 (破裂時の張力) を損なわないことです.
- この研究は,HDPEの機械的完全性を犠牲にすることなく,特定の用途の処理を最適化するための経路を提供します.
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