1H NMR spectra of poly(methyl methacrylate) prepared with benzoyl peroxide in toluene at 100 °C were measured on a 750 MHz high-resolution NMR spectrometer. End groups resulting from initiation, chain transfer, and termination reactions were assigned, and the numbers of end groups per polymer molecule were estimated. End-group signals showed splittings due to stereochemical sequences near the chain ends, the analysis of which indicated that the racemo diad at the chain end attached with C6H5− was higher than that with C6H5COO−.

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The spin-decoupled 'H NMR and 13C NMR methods were presented for the determination of the cis-trans sequence distribution in polybutadiene. Poly(butadiene-2,3-d2) and cis-trans isomerized polybutadienes were used for the peak assignment and the resonance of methylene protons in cis-trans linkage could be described as an A2B2 system. The dyad and triad sequence distributions of cis-l,4 and trans-1,4 units were determined for isomerized, equibinary and lithium catalyzed polybutadienes, and polycyclooctadienes. The accuracy of the measurements was also studied comparing the results with those by infrared method.

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