| In this paper,the preparation of high Cis-polyisoprene by anionic polymerization was studied.The effect of polymerization conditions and methods on the polymerization of isoprene(Ip) without structure regulator,the effect of the amount of structure regulator, polymerization conditions and methods on the polymerization of isoprene with kinds of structure regulators and comparison of their ability of adjusting the content of Cis-1,4 of polyisoprene,the polymerization kinetics of isoprene with carbon disulfide as structure regulator and the molecular weight and its distribution of polyisoprene were carried out.The results showed that:1) In the homopolymerization system of isoprene without structure regulator,the content of Cis-1,4 structure has reached 92.0%at the point of m(Ip)/m(cyclohexane)(mass ratio)=1:9,n(n-BuLi)/n(Ip)(molar ratio)=0.34×10-3 at 0℃for 7 days.It achieved the general level of high Cis-1,4 polyisoprene.But the conversion of isoprene only reached 0.09.The rate of polymerization of isoprene was too slow.2) The content of Cis-1,4 structure of polyisoprene could be raised by the structure regulators of 1-bromobutane,triisobutyl aluminium,m-bromobenzene, m-bromobenzene/triphenylphosphine and carbon disulfide.3) The regulation capability of these regulators for Cis-1,4 structure of polyisoprene: carbon disulfide＞m-bromobenzene/triphenylphosphine＞m-bromobenzene＞1 -bromobutane＞triisobutyl aluminium.4) The content of Cis-1,4 structure of polyisoprene reached 96.2%at the point of m(Ip)/m(cyclohexane)=1:9,n(n-BuLi)/n(Ip)=0.68×10-3,n(CS2)/n(n-BuLi)=0.08×10-3 at 50℃for 4h.The conversion of isoprene reached 0.90.It has achieved the general level of high Cis-1,4 polyisoprene,while it has the potential value of industrialization.5) With the addition of carbon disulfide,the rate of polymerization of isoprene declined and the apparent activation energy increased.6) With the polymerization temperature increasing,the rate of polymerization of isoprene increased significantly.
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