13C-NMR STUDY OF SEQUENCE STRUCTURE OF PBD
13C-NMR研究聚丁二烯的序列结构

Several polybutadiene samples prepared with different catalysts Were studied by 13C-NMR. It is shown by analyzing the molecular chain of polybutadiene that there are three sequences (cis 1,4-sequence, trans 1,4-sequence and 1,2-sequence) and seventeen aliphatic carbon nuclei in it. These nuclei contribute to the sixteen peaks on the 13C-NMR spectrum of polybutadiene. A group of empirical parameters is obtained by analyzing the chemical shift data of the peaks. When using them in our case, the calculated values of chemical shift of the peaks agree quite well with the experimental ones. A T4peak,the fouth peak oftrans 1,4sequence,was first discovered by the present work.Quantitative treatment of the se-quence structure ofpolybutadiene was preliminaryly studied.