¹H NMR studies of molecular relaxations of poly‐1‐butene

This is the authors' abstract. We don't add key points for this paper.

The temperature dependance of the proton NMR line shape, T 1 and T 1ρ of isotactic poly‐1‐butene forms I, I′, II, and III have been studied between 100 and 400 K (up to melting). The usual line shape decompositions concerning rigid vs. crystalline and mobile vs. amorphous phases are discussed. The rigid‐lattice second moments were calculated introducing a fast rotation of the methyl group. Complex spin‐lattice decays were analyzed as a continuous distribution of rates. Relaxation behavior was analyzed in terms of a Williams‐Watt correlation function. Motions in the crystalline parts of samples in forms II and III very similar to the amorphous one were revealed, leading us to compare form II to a condis crystal during the crystal form transformation.