RAPID COMMUNICATION: PBT chain mobility from the ESR saturation
spectra studies (in English)
Polimery 2003, No 7-8, 557
Temperature and microwave power dependence of ESR spectra of the spin probes in PBT has been studied. The observed changes of ESR signal allowed to determine the long correlation times (τ ≈ 10-4-10-5 s) as well as other parameters characterizing the saturation processes and involved relaxation processes. It was established that at low temperature range (≈ 120-200 K) the rotational mobility of used nitroxide radicals was related to local relaxation processes of the methylene sequences (3-4 CH2 groups) in an amorphous region of PBT. The obtained results show the possibility of that type of investigation also for other polymers. Determination of polymer properties via analysis of parameters obtained in saturation experiments is also raised.
Keywords: poly(butylene terephtalate), electron spin resonance (ESR), spin probes, relaxation processes, ESR saturation effects
PBT chain mobility from the ESR saturation spectra studies (in English)