A series of ethylene|vinyl alcohol copolymers (EVOH) with different comonomer contents were studied by both solution state and solid|state high|resolution 13 C NMR spectroscopy. A new assignment of 13 C CP/MAS spectrum of EVOH was given. It was demonstrated that the triple splitting of the signal of methine carbon of the vinyl alcohol unit in 13 C CP/MAS spectrum is caused by sequence distribution,tacticity and intra and inter molecular hydrogen|bonding interactions.
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