TY - DATA T1 - Spin-Trapping Analysis and Characterization of Thermal Degradation of Thermoplastic Poly(ether–ester) Elastomer PY - 2018/01/30 AU - Masayo Sono AU - Kenji Kinashi AU - Wataru Sakai AU - Naoto Tsutsumi UR - https://acs.figshare.com/articles/journal_contribution/Spin-Trapping_Analysis_and_Characterization_of_Thermal_Degradation_of_Thermoplastic_Poly_ether_ester_Elastomer/5838270 DO - 10.1021/acs.macromol.7b02654.s001 L4 - https://ndownloader.figshare.com/files/10337160 KW - PBT KW - DSC KW - OCH KW - co KW - DMA KW - PEO KW - TPEE KW - CH KW - NMR KW - TGA KW - ESR KW - GPC KW - thermo-oxidative degradation N2 - We investigated the thermal degradation of poly­(butylene terephthalate)-co-poly­(ethylene oxide) (PBT-co-PEO), a thermoplastic poly­(ether–ester) elastomer (TPEE), through proton nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), gel permeation chromatography (GPC), and spin-trapping electron spin resonance (ESR) analysis to detect radical intermediates present during degradation. Three kinds of PBT-co-PEO with different component ratios of PBT/PEO were synthesized. The thermal degradation process of PBT-co-PEO was divided into four weight-loss stages. In the first stage from room temperature to 120 °C, we confirmed the production of two radical intermediates, O–•CH–CH2 and •CH2–, by the spin-trapping method. This suggested that the initial decomposition occurred at the OCH2–CH2O bond in the PEO units. Upon annealing at 120 °C, PBT-co-PEO showed a small degree of random degradation, while higher PBT contents induced gelation and the production of the characteristic oligomer PBT–PEO–PBT. The gelation was attributed to cross-linking between two O–•CH–CH2 moieties of PBT. In the second stage from 120 to 340 °C, a large thermo-oxidative degradation of the PEO segment occurred, accompanied by an increase in the radical amount of spin adducts. In the third stage, the thermo-oxidative degradation of PBT units was observed. The radical intermediates were thus shown to be a primary factor of the thermal degradation characteristics of TPEE. ER -