Hindered Rotation in Poly(N-acyl)iminoalkylenes - A 13C Nuclear Magnetic Resonance Study
نویسندگان
چکیده
Poly(N-acetyl)iminoethylene. poly(N-propionyl)iminoethylene and poly(N-acetyl)-2,2-dimethyliminoethylene were prepared by cationic polymerization in solution of 2-methyl2-oxazoline, 2-ethyl-2-oxazoline, and 2,4,4-trimethyl-2-oxazoline respectively. The 13C NMR spectra of the polymers obtained showed different sets of shifts for the carbon atoms of the backbone as well as for the N-acylimino side chain due to the restricted rotation of the Nacylimino group. The temperature dependence of the N-acylimino side chain signals showed a different coalescence behaviour depending on the substituents at both the main and the side chain.
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