STRATEGIES FOR STRUCTURAL AND QUANTITATIVE-ANALYSIS OF HETEROGENEOUS BLOCK-COPOLYMERS BY C-13 MAS NMR-SPECTROSCOPY

Strategies for structural and quantitative analysis of unknown heterog eneous block copolymers employing solid-state C-13 magic-angle spinnin g (MAS) NMR techniques are presented. Combinations of standard single- pulse, cross-polarization, cross-polarization-depolarization, and SEMU T spectral editing MAS experiments enable efficient separation, identi fication, and quantitation of resonances from mobile as well as immobi le phase constituents of heterogeneous polymers. The utility of these techniques for structural and quantitative analysis of complex polymer s is demonstrated for three block copolymers, initially of unknown str ucture and composition. The three samples investigated here have been identified as polypropylene/polyethylene/ethylene-propene-diene rubber (PP/PE/EPDM), polyethylene/ethylene-propene rubber (PE/EPR), and poly styrene/polyethylene/butadiene rubber (PS/PE/BR).