Solid state 1H NMR study of molecular dynamics and domain sizes in PBT with the fullerene derivates: Decylamine–C60 and tetracyanoethylene oxide–C60

The solid-state 1H NMR on-resonance and off-resonance techniques have been performed to study molecular dynamics and domain sizes in heterogenous nanocomposites based on poly(butylene terephthalate) and nanoparticles C60 modified by n-decylamine (DA) or tetracyanoethylene oxide (TCNEO), respectively. The spin-lattice off-resonance relaxation times in the rotating frame T1ρoff as well as the second moment M2 of the absorption line were analysed as a function of temperature. To determine the size of heterogeneities and characterize the morphology of the nanocomposites, the 1H NMR spin-diffusion experiment designed by Goldman–Shen [1,2] was performed. The results from the measurements allow us to investigate the spin-diffusion phenomenon and relaxation behavior of the new nanocomposites.

Research Highlights
► We perform the study of molecular dynamics and domain sizes in new nanocomposites.
► We examine the changes of the crystallinity, the correlation times and the activation energies.
► The spin-diffusion data indicate larger domain sizes of the mobile phase for the PBT/DA/C60 relative to those for the PBT/TCNEO/C60.
► The NMR studies show hindered molecular motion in nanocomposites than that of PBT.