| 摘要 |
<p>The invention is a practical process for anionically synthesizing commercially significant quantities of macrocyclic polymers from polar and/or non-polar monomers by using Group IIA and IIB metal cyclic organometallic initiators. Activation of the ring metal atom results in anionic polymerization of the monomers by addition into the initiator ring at the bonds between the atom and its two adjacent carbon atoms, the metal atom acting as a bridge between the two living ends of the propagating chain. Coupling of the cyclic polymer living ends by coupling agents produces macrocyclic polymers that are stable in air and moisture and that exhibit desirable properties, such as low viscosities at high molecular weights. Such macrocyclic polymers provide enhanced polymer processability during molding, extruding and the forming of films. Macrocyclic polymers terminated with coupling agents that also provide functional groups may be compounded to produce vulcanizable elastomeric compounds and articles that exhibit reduced hysteresis properties.</p> |
