Determination of the composition of common linear low density polyethylene copolymers by13C‐NMR spectroscopy

摘要

AbstractA comprehensive13C‐NMR method for the analysis of composition in the most common commercial polyethylene copolymers has been established. The method covers ethene copolymers with propene, butene‐1, hexene‐1, octene‐1, and 4‐methyl pentene‐1 in the composition range of 1–10 mol . The chemical shift assignments andT1values of the resonances of the copolymers are presented. Results of precision studies and interlaboratory analyses showed that the molar composition could be determined with a relative precision at 2δ of about 6. This method is being proposed to ASTM as Met