Carbon‐13 nuclear magnetic resonance quantitative measurements of monomer sequence distributions in hydrogenated polybutadienes

The 1,4–1,2 additions in three hydrogenated polybutadienes are described in terms of triads of monomer units, average sequence lengths, and branches per 1000 carbon atoms. A test for conformity with Markov statistical behavior shows that the measured triad distributions can be closely reproduced assuming a first‐order model. Transition probabilities from the statistical analysis can be used to calculate the relative concentration of any desired sequence. Steric factors during polymerization may lead to the first‐order bias in the monomer distribution.