Polybutadiene (PB) and hydroxyl-terminated PB were epoxidized using in situ-generated
dimethyl dioxirane as an oxidant in the attendance of different concentrations of copper
and lead (2-guanidinobenzimidazoliume) (GBH) complexes as the catalyst at 25
C. The
potential of cis, trans, and vinyl double bonds toward epoxidation was considered in
detail at various reaction times. The products were characterized using proton nuclear
magnetic resonance and Fourier transform infrared spectroscopy techniques and data
revealed that the formation of desired products were obtained without any side reac-
tion. The results indicated the performance of calculated 0.252 mmol of GBH complexes
in obtaining maximum epoxidation yield as well as selectivity in the epoxidation of cis
double bonds in comparison with trans and vinyl ones
