Development of Quantitative Evaluation on Molecular Aggregation in Polymeric Materials by Means of Dynamic Infrared Spectroscopy

首先，在对动态红外光谱系统的光学系统进行改进后，对光学系统中的各种机器常数进行了详细的测量。其次，在1500和1800 cm^<-1>的波数范围内测量了分节聚脲（SPUU）红外吸收光谱的静态应变依赖性，得到了三种属于C=O拉伸模式的吸收谱带。这些被分配给在软段的氢键和无氢的氨基甲酸乙酯羰基，以及在硬段的氢键尿素羰基。详细分析了三个波段中峰位置、峰高和峰宽对应变的依赖关系。利用这些静态数据，模拟了红外光谱的动态变化，并与动态数据进行了对比。结果表明，薄膜厚度的动态变化可以类似于等体积下的变形。最后，对spu的动态红外同相分量进行了分析，结果表明spu的软段为正取向，硬段为负取向。在-10℃时，尿素羰基的非相组分使平行极化和垂直极化沿应变轴方向发生相反方向的动态峰移。相对静态和动态二向色差光谱经尿素波段峰高归一化后，除比尿素波段的波数低外，两者具有较好的一致性。另一方面，对于平均吸光度相同的归一化光谱给出了软段和硬段之间的明显区别。根据这一差异，尿素羰基的氢键被键上的动态应变破坏。通过对静态和动态二向色差光谱的相似性以及静态和动态平均吸收光谱的差异的讨论，可以得出结论：沿着脲羰基键的应力对硬段结构域的取向起重要作用，而不是沿着聚合物链的应力。即软段作为基体组分朝向应变方向，而硬段由于尿素羰基键方向的应力垂直于硬段链，因此与应变轴方向垂直。少

First of all, after improvement of the optical system in our dynamic infrared (DIR) spectroscopic system, various kinds of machine constants in the optical system were measured in detail.Second, static strain dependence of infrared absorption spectra in segmented poly(urethaneurea) (SPUU) were measured at wavenumber range of 1500 and 1800 cm^<-1>, where we got three kinds of absorption bands attributed to C=O stretching modes. These are assigned to the hydrogen-bonded and hydrogen-free urethane carbonyls in the soft segments, and hydrogen-bonded urea carbonyl in the hard segments. The strain dependence of peak positions, peak hights, and peak widths in three bands were analyzed in detail. By using these static data, the dynamic change of infrared spectra were simulated and compared with the dynamic data. As a result, it was confirmed that the dynamic change in film thickness could be similar to the deformation under constant volume.Finally, the in-phase components in dynamic infrared s … More pectra of SPUU give the positive orientation of the soft segments and the negative orientation of the hard segments. The out-of-phase components of the urea carbonyl groups at -10℃ give the dynamic peak shift of the opposite directions for the parallel and perpendicular polarizations along the strain axis.The relative static and dynamic dichroic difference spectra normalized by the peak height of the urea band are in good agreement except at a lower wavenumber than that at the urea band. On the other hand, the same normalized spectra for the average absorbances give the clear difference between the soft and hard segments. It is derived from this difference that the hydrogen bonds of the urea carbonyl are broken by the dynamic strain along the bonding.From the above discussion on the similarity between the static and dynamic dichroic difference spectra and the difference between the static and dynamic average absorption spectra, it is concluded that stress along the urea carbonyl bonds, but not along the polymer chains, takes an important role on the orientation of the hard segment domains. That is, the soft segments as a matrix component orient toward the strain direction, however the hard segments make perpendicular orientation to the strain axis due to the stress along the urea carbonyl bond, which is perpendicular to the hard segment chain. Less