The high cis-1

4-polyisoprene is prepared by Ziegler-Natta coordination polymerization. The effect of preparation method and condition of heterogeneous TiCl4-Al(i-Bu)3 two component catalyst on isoprene polymerization are investigated. The influence of several parameters on the catalytic activity

the gel content

intrinsic viscosity

microstructure and cis-1

4-content of the polyisoprene is examined in detail

including mole ratio of catalyst component

prefabricate temperature and aging time as well as catalyst dosage

polymerization temperature and time. The results show that the optimum conditions of catalyst preparation are as follows: the molar ratio of Al/Ti is 1.0

the temperature of prefabricate is at -40℃

the aging time is 2 h at room temperature

molar ratio of Ti/Ip(catalyst content)is 6×10-3

the polymerization for 5 h at 50℃. Under these condition

the monomer conversion is 87.1% in the polymerization

the microstructure cis-1

4 content in obtained polymer is up to 91.76%.