State Analysis of Water in the Macromolecule of Polyol Studied by the New High-Frequency Spectroscopy

聚环氧乙烷(PEG)中的水分子主要用高频光谱分析。聚乙二醇的亲水性来源于环氧乙烷(EC)单元中的两个孤对氧原子。不同EO：H_2O比的样品，特别是在1：2附近，水分子与PEO结合的行为会有所不同。高频光谱分析发现，PEO中水分子的抑制特征可分为EO：H_2O比的四个区域。在区域1(EO：H2O=1.0~1.25)，水分子之间没有缔合，但与EO氧原子结合强烈。在区域2(EO：H2O=1.25~2.0)，水分子与EO氧结合，同时以氢键相互作用。在第三区(EO：H2O=2.0~10.0)，几乎所有的水分子都是相互缔合的，具有一定的结合性质。在第4区(EO：H2O=100~)，PEO中水分子的性质与散体水(或可冻水)非常接近。

Water molecules contained in polyethylene oxide (PEG) have been analysed mainly by high-frequency spectroscopy. The hydrophilicity of PEG comes from the two lone pairs of oxygen atom in ethylene oxide (EC) unit. Two water molecules may directly be attached to the EO oxigen, so that the behavor of water molecules bound to PEO would be varied for samples with different EO : H_2O ratio especially arround 1 : 2. The restrained character of the water molecules in PEO has been found to be divided into four regions of EO : H_2O ratio from the analysis of high-frequency spectra. In region 1 (EO : H_2O=1.0〜1.25), the water molecules are not associated to each other, but strongly bound to the EO oxygen atoms. In region 2 (EO : H_2O=1.25〜2.0), water molecules are bound to the EO oxygen, and at the same time they are associated to each other by hydrogen bonding. In region 3 (EO : H_2O=2.0〜10.0), almost all the water molecules are associated to each other, with bound character to some extent. In region 4 (EO : H_2O=100〜), the character of water molecules in PEO are very close to that of bulk water (or freezable water).