A C-13 NMR determination for monomer compositions in ethylene-propylene copolymers, ethylene-propylene-butene-1, and elthylene-propylene-diene terpolymers

Abstract

The monomer compositions in a series of propylene heterophasic copolymer, propylene random copolymer, propylene random terpolymer and ethylene-propylene-2-ethylidiene-5-norborane (ENB) terpolymer have been determined from C-13 NMR spectra. The simplified and highly resolved C-13 NMR spectra made it possible to assign unambiguously and calculate the monomer compositions. A complete sets of NMR chemical shift assignments and the way to measure the quantity of monomer are newly given in diverse polymers. Furthermore, it is shown that complete dyad, triad, tetrad and pentad distributions can be determined by C-13 NMR spectra. These NMR quantitative analytical determinations for monomer compositions are consistent with those from Infrared spectroscopic data.