Quantitative Analysis of Mixtures of Ethylene- and Propylene-Based Polymers by Temperature-Rising Elution Fractionation and exp 13 C Nuclear Magnetic Resonance

The fraction soluble in boiling heptane of a mixture of polypropylene, polyethylene and ethylene--propylene copolymer was characterized by exp 13 C nuclear magnetic resonance (n.m.r.) combined with temperature-rising elution fractionation. Two mathematical models were used to achieve quantitative analysis of the fractions from n.m.r. triad data. The result indicates that the ethylene--propylene copolymer made with an MgCl sub 2 /TiCl sub 4 -supported catalyst contains two or three major components and that the polypropylene exhibits high compositional heterogeneity. Simulation of the exp 13 C n.m.r. spectrum was successfully used to confirm the results.