The 50.3 MHz 13C NMR of radically initiated poly(trans-4-methacryloyloxyazobenzene) was studied in CDCl3 solution at room temperature. Resonance assignments were made by comparison with low molecular weight structural analogs and from dynamic measurements. Restricted internal rotation of the side chain azobenzene group was found to be responsible for the splitting of some aromatic carbon signals. The carbonyl, methyl and main chain quaternary carbons gave rise to multiplets attributable to pentad and triad stereosequences. Their intensity distribution closely fitted a Bernoullian statistics (Pm=0.257) consistent with a predominantly syndiotactic structure of the polymer backbone. Molecular dynamics in solution was investigated by 13C T1 and NOEF measurements.
|Autori:||Solaro R; Altomare A|
|Titolo:||C13 Nuclear-Magnetic-Resonance study of poly(trans-4-methacryloyloxyazobenzene)|
|Anno del prodotto:||1990|
|Digital Object Identifier (DOI):||10.1016/0032-3861(90)90143-M|
|Appare nelle tipologie:||1.1 Articolo in rivista|