Characterization of the Chain-Ends and Branching Structures in Polyvinylidene Fluoride with Multidimensional NMR

Abstract

Multidimensional solution NMR (¹⁹F, ¹H, and ¹³C) has been used to determine chain-ends and backbone branching points and to obtain unambiguous ¹⁹F and ¹H resonances assignments from these chain-ends and branching structures in poly­(vinylidene fluoride) (PVDF). The multidimensional NMR methods employed in this study not only enabled the resonance assignments of the last monomer of the chain but also provided assignments for the last three monomer units of chain-end structures. The chain-end signals from PVDF were determined using spin–lattice relaxation measurements and 2D diffusion ordered spectroscopy (DOSY) analysis. 2D-NMR analyses were also used to assign resonances of chain branching points along the backbone of the polymer