Naslov
Spin probe ESR and deuterium probe NMR method in studying some polymer systems

Autori
Valić, Srećko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, ostalo

Izvornik
18th European Symposium on Polymer Spectroscopy, Book of Abstracts / Volovšek, Vesna ; Bistričić, Lahorija ; Movre, Šapić, Iva - Zadar, 2010, 4-4

Skup
18th European Symposium on Polymer Spectroscopy

Mjesto i datum
Zadar, Hrvatska, 19.09.2010. - 22.09.2010

Vrsta sudjelovanja
Plenarno

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Spin probe; ESR; deuterium probe; NMR

Sažetak
Nitroxyl radicals of various size, shape and polarity are often used for the study of polymer systems by electron spin resonance (ESR)1. Spin probe method supposes that they are incorporated in a polymer matrix by diffusion and that there is no chemical bond between the nitroxyl radical and polymer chain. The use of this method will be illustrated through the recent studies of natural rubber (NR) films crosslinked by -irradiation using various doses in the presence of uniaxial constraint, NR composites and NR/PMMA semi interpenetrating polymer networks, Fig.1. The influence of matrix composition, structure, crosslink density and spatial orientation of chain segments on the local dynamics will be discussed. Deuterium NMR spectroscopy is known as a powerful tool in studying anisotropic molecular motions. Deuterium labeled polymers are rarely available and their synthesis is very expensive and time consuming. Therefore, the use of deuterium probes is particularly interesting. Various swelling agents, like good solvents or matrix like chains were proved to be good NMR probes2. They can be introduced in a polymer matrix mostly by diffusion. Studies of orientational dynamics in two different anisotropic systems will be presented: (i) segmental motions followed by deuterated cyclohexane probe in NR films crosslinked under uniaxial extension and (ii) the influence of crystalline phase on segmental motions in the amorphous phase of PDMS for PS-PDMS lamellar diblock copolymer, investigated by n-octane probe. References [1] Z. Veksli, M. Andreis, B. Rakvin, Prog. Polym. Sci. 25, 949-986 (2000). [2] S. Valić, B. Deloche, Y. Gallot, A. Skoulios, Polymer 36, 3041-3044 (1995).

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA