abstract |
This invention deals with an approach to control anionic polymerization. The anionic polymerization is conducted by adding a kind of initiator ligand compound, directly or in the form of solution into the monomer or initiator at the same or different time, or at different stages. The metal atoms in the ligand can form the association with the initiator cations, while the alkyloxy groups in the intiator ligand can restrict the entering channel of the addition of the monomers due to their relatively large volume or steric hindrance. Therfore, the initiator ligand compound can restrict the rate of anionic polymerization, restrain the side reaction, and make the anionic polymerization possible to be conducted at room or even higher temperature. n The molar ratio of initiator ligand compound to initiator is from 0.01:1 to 20:1. Compared with present technologies, the method of this invention can control and adjust the homopolymerization and copolymerization rate, side reactions and the polymerization temperature, and make it possible to industrialize. |