Poly(ethylene-co-1-octene) Characterization by High-Temperature Multidimensional NMR at 750 MHz

Herein are presented the 188.6 MHz 13 C NMR spectra (corresponding to 750 MHz 1 H resonance frequency) of a series of copolymers from ethylene and 1-octene monomers. These spectra permit the resolution of unique 13 C resonances from hexyl chain branches. The 750 MHz high-temperature pulsed field gradient (PFG), heteronuclear multiple quantum correlation (HMQC), and heteronuclear multiple-bond correlation (HMBC) two-dimensional (2D) NMR spectra of ethylene/1-octene copolymers are also presented. Data are presented from a new probe capable of performing high-temperature PFG coherence selection experiments at temperatures typical of those used in many polymer analyses. The performance of this probe is illustrated with PFG−HMQC and PFG−HMBC spectra of copolymers from ethylene/1-octene at 120 °C. Detailed unequivocal proof of the resonance assignments for poly(ethylene- co- 1-octene) is reported. The 2D NMR spectra were used to confirm 1 H and 13 C chemical shift assignments previously determined by empirical methods. Quantitative analyses of the ethylene/1-octene copolymers were also performed.