By using the neodymium chloride compounds(［Nd］)［NdCl34L

L:TBP (tributyl phosphate)

TPP(triphenyl phosphate)

P204(di(2-ethylhexly)phosphoric acid)］ as the catalyst while the methylaluminoxane (［Al］) as the cocatalyst

the polymerization of 1

3-butadiene could be carried out in cyclohexane to obtain high cis-content and narrow molecular weight distribution polybutadienes.In this article

the polymerization activities

and the molecular weight

the molecular weight distribution and the microstructure of the products were examined on the basis of the the effects of the ligands

the amounts of the methylaluminoxane

the aging time and the solvents on the 1

3-butadiene polymerization.It was considered that the polymerization activities of the ligands were in the order of TBP P204 TPP

which was attribute to the differences among the electron donor group inductive effect of the ligands; when the ［Al］/［Nd］ was 30

the GPC curve was unimodal

indicating the single-active-site in the polymerization process

which revealed that the molecular weight distribution was narrow (1.20).By means of aging at 30℃

the cis-content of polybutadienes were over 97.2% which was determined by IR and confirmed by NMR.Compared with toluene and hexane

by using cyclohexane as the polymerizing solvents

high cis-content and narrow molecular weight distribution polybutadienes were obtained and the catalyst system was at the highest polymerization activity

which revealed that the cyclohexane was the proper solvent for the polymerization.