| 초록 |
Difunctional initiators are of considerable interest for the preparation of triblock copolymers because of its lower cost and easier processability. The stoichiometric reaction of 1,3-diisopropenylbenzene(DIB) with two moles t-BuLi which was prepared at -20℃ could be used as the useful difunctional initiator. However, the high cost, storage difficulty of t-BuLi and strict reaction condition(-20℃) have limited its utility. In our study, n-BuLi has been used instead of t-BuLi. But the component of DIB/2 n-BuLi adducts includes a large amount of oligomers. So several isoprene(Ip) units has been added to form a unimodal seeded initiator. The GPC curves of polyisoprenes initiated by this DIB/2 n-BuLi/10 Ip initiators which were prepared at 50℃ was unimodal and the Mn was consistent with the calculated one. The high temperature for initiation and propagation, and the presence of Ip units may be helpful for the synthesis of DIB/n-BuLi/5 Ip adduct used as the difunctional initiator. |
