2次元NMRによるガラスのようなポリエステル,PETにおける鎖の形状の解明
Schmidt-Rohr1, Hu, Zumbulyadis
1K. Schmidt-Rohr and W. Hu, Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA 01003, USA. N. Zumbulyadis, Imaging Research and Advanced Development, Eastman Kodak Company, Rochester, NY 14650-2132, USA.
Science (New York, N.Y.)
|May 13, 1998
まとめ
ポリエチレンテレフタレート (PET) 鎖の形状は,核磁気共鳴 (NMR) を使用して研究されました. アモルフなPETは,ポリエステル材料の特性に影響を与える重要なガッチ形状を示しています.
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
- スペクトル顕微鏡検査です.
背景:
- ポリエチレンテレフタレート (PET) は広く使用されているポリエステルです.
- 鎖の形状を理解することは,材料の性質を予測するために極めて重要です.
- ガラスのPETは結晶状態と無形状態の両方で存在し,鎖の配置が異なります.
研究 の 目的:
- ガラスのようなポリエチレンテレフタレート (PET) の鎖形状を特徴付けるために.
- 形状のないPETと結晶のPETでトルションアングルの統計を定量化するために.
- 鎖の形状をポリエステルの潜在的な材料特性と相関させるため.
主な方法:
- 2次元の二重量子核磁共振 (NMR) スペクトロスコピーを利用しました.
- 強化されたNMR信号検出のために,炭素13のラベルを使用した.
- トランスとゴーシュ形状を区別するために,NMRスペクトルパターンを分析した.
主要な成果:
- 結晶型PETは100%のトランスコンファメーションを示しています.
- アモルフなPETは,約14%のトランスコンファメーションを含んでいる.
- アモルフなPETには,平均70度の左折角が判定されました.
結論:
- PETの鎖形状は,結晶状態と無形状態の間で大きく異なっています.
- アモルフなPETにおけるガウス形状の普及は,その物理的特性に影響を与えます.
- これらの発見は,ポリエステルの構造-特性関係に関する洞察を提供します.
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