Peng Yun, Wu Peiyi, Siesler H W
Department of Macromolecular Science and The Key Laboratory of Polymer Engineering Science, Fudan University, 200433 Shanghai, PR China.
Biomacromolecules. 2003 Jul-Aug;4(4):1041-4. doi: 10.1021/bm0340624.
In the present contribution, two-dimensional ATR-FTIR spectroscopy was used to study the diffusion of water in poly(epsilon-caprolactone) (PCL). In the spectral region of the nu(OH) stretching vibration of water, four absorption bands (3635, 3560, 3411, and 3220 cm(-1)) can be identified. The higher wavenumber band pair at 3635 and 3560 cm(-1) is assigned to the antisymmetric and symmetric OH stretching vibrations, respectively, of water which is partially hydrogen-bonded to the carbonyl groups of PCL, whereas the lower frequency band pair at 3411 (antisymmetric) and 3220 cm(-1) (symmetric) is attributed to the OH stretching vibrations of bulk water which is fully hydrogen-bonded to other water molecules. From the asynchronous map of a 2D correlation analysis of spectra recorded during the diffusion of water into PCL, it was concluded that during the diffusion process the water molecules first penetrate into the free volume (microvoids) of the PCL matrix or are molecularly dispersed in the polymer matrix and then form hydrogen bonds with the C=O groups of the polymer.
在本论文中，采用二维衰减全反射傅里叶变换红外光谱（ATR-FTIR）研究了水在聚己内酯（PCL）中的扩散。在水的ν(OH)伸缩振动光谱区域，可以识别出四个吸收带（3635、3560、3411和3220 cm⁻¹）。波数较高的3635和3560 cm⁻¹处的吸收带分别归属于与PCL羰基部分氢键结合的水的反对称和对称OH伸缩振动，而频率较低的3411（反对称）和3220 cm⁻¹（对称）处的吸收带则归因于与其他水分子完全氢键结合的大量水的OH伸缩振动。从水扩散到PCL过程中记录的光谱的二维相关分析的异步图谱得出结论，在扩散过程中，水分子首先渗透到PCL基质的自由体积（微孔）中或分子分散在聚合物基质中，然后与聚合物的C=O基团形成氢键。
