Dynamic behavior of polymer films in the presence of plasticizers by using ATR-based dynamic compression modulation step-scan Fourier transform infrared spectroscopy,and 2D correlation analysis

Attenuated total reflection (ATR)-based dynamic compression modulation two-dimensional (2D) correlation study of iso-phthalate based polyester (PES) films in the presence or absence of triphenyl phosphate (TPP) is carried out. In the PES without TPP, the dynamic response of side-chain (CO) groups is faster than that of the backbone (CCO) stretching, which is similar to the sequential result of our previous paper. With 15% TPP, the response of the backbone (CCO stretching) bands become faster than the side-chain (CO stretching) bands. In the case of 35% TPP, although slight differences are found, almost all of the observed peaks become synchronized with each other. The dynamic response feature is dramatically altered in the 45% TPP, suggesting that a transition point of larger molecular environment changes may exist between 35% and 45%. A model is proposed to explain these dynamic response features.