| 초록 |
We have been developing new strategies to prevent trimerization in anionic polymerization of the isocyanate monomers. We found that trimerization is significantly minimized when 15-crown ether-5 or sodium tetraphenylborate are used as additives in the polymerization of HIC. In the event, sodium benzanilide (Na-BA) which serves the dual function of controlled initiation as well as chain end protection, is fit in our purpose. We compare several oxy initiators which successfully control to polymerize isocyanate or not. As a general rule, activity of oxy anion is less than C- or N-, so more stable. At the first time, we designed alkyl oxy anion and phenoxide anion. From the result, controlling polymerization of isocyanate was not success. Therefore we introduced another initiator containing a stabilizing group such as aromatic groups beside alkyl oxy group. During the polymerization process of HIC, side reaction at initiation step and propagation step was prevented, in this system. |
