Abstract We have developed an advanced rheo-optical method; based on pulse-induced dynamic compression ATR step scan time-resolved-FT-IR spectroscopy. By inserting a massive weight between a film sample and a piezo electric actuator; a clear ring-down compression signal has been successfully detected according to inertial effect obtained from the film sample and massive weight. This rheo-optical method was named as Pulse-induced Dynamic Compression (PDC) method. PDC method detects nonlinear dynamic reorientational responses of electric dipole transition moments of given functional groups. In the present study, we have additionally equipped PDC with a heating apparatus on the top of the massive weight to analyze nonlinear molecular dynamics of uncrystalized polyester under different temperature conditions. By monitoring the polyester's C = O stretching (1718 cm-1), and ester C-C-O vibrational regions (1307 - 1225 cm-1), two types of dynamic responses were found under different temperatures: complex reversible positive responses, and relatively simple reversible negative dynamic responses. Difference between the C = O and C-C-O functional groups is also found, suggesting that they exist in inhomogeneous surrounding environments. Further detailed study has been performed by using a DFT spectral simulation and 2D-IR analysis.

中文翻译：

---

使用脉冲诱导动态压缩 (PDC) IR 方法分析加热下未结晶聚酯的非线性结构动力学

摘要 我们开发了一种先进的流变光学方法；基于脉冲诱导动态压缩 ATR 步进扫描时间分辨 FT-IR 光谱。通过在薄膜样品和压电执行器之间插入一个巨大的重量；根据薄膜样品和大量重量获得的惯性效应，成功检测到清晰的衰荡压缩信号。这种流变光学方法被命名为脉冲诱导动态压缩（PDC）方法。PDC方法检测给定官能团的电偶极子跃迁矩的非线性动态重定向响应。在本研究中，我们在重块顶部额外配备了带有加热装置的 PDC，以分析不同温度条件下未结晶聚酯的非线性分子动力学。通过监测聚酯' s C = O 伸缩 (1718 cm-1) 和酯 CCO 振动区域 (1307 - 1225 cm-1)，在不同温度下发现两种类型的动态响应：复杂的可逆正响应和相对简单的可逆负动态响应。还发现了 C = O 和 CCO 官能团之间的差异，表明它们存在于不均匀的周围环境中。通过使用 DFT 光谱模拟和 2D-​​IR 分析进行了进一步的详细研究。表明它们存在于不均匀的周围环境中。通过使用 DFT 光谱模拟和 2D-​​IR 分析进行了进一步的详细研究。表明它们存在于不均匀的周围环境中。通过使用 DFT 光谱模拟和 2D-​​IR 分析进行了进一步的详细研究。