无水海藻糖和麦芽糖玻璃的介电松弛研究。

Study of dielectric relaxations of anhydrous trehalose and maltose glasses.

机构信息

Department of Nanomaterials Engineering & BK21 Nano Fusion Technology Division, Pusan National University, Miryang 627-706, Korea.

出版信息

J Chem Phys. 2011 Jan 7;134(1):014508. doi: 10.1063/1.3517217.

DOI:10.1063/1.3517217

PMID:21219008

Abstract

We investigated the frequency dependent dielectric relaxation behaviors of anhydrous trehalose and maltose glasses in the temperature range which covers a supercooled and glassy states. In addition to the α-, Johari-Goldstein (JG) β-, and γ-relaxations in a typical glass forming system, we observed an extra relaxation process between JG β- and γ-relaxations in the dielectric loss spectra. We found that the unknown extra relaxation is a unique property of disaccharide which might originate from the intramolecular motion of flexible glycosidic bond. We also found that the temperature dependence of the JG β-relaxation time changes at 0.95T(g) and it might be universal.

摘要

我们研究了无水海藻糖和麦芽糖玻璃在涵盖过冷和玻璃态温度范围的频率相关介电弛豫行为。除了典型玻璃形成体系中的 α-、Johari-Goldstein (JG) β-和 γ-弛豫之外，我们还在介电损耗谱中观察到 JG β-和 γ-弛豫之间的额外弛豫过程。我们发现，未知的额外弛豫是二糖的独特性质，可能源于柔性糖苷键的分子内运动。我们还发现，JG β-弛豫时间的温度依赖性在 0.95T(g) 处发生变化，这可能是普遍现象。