| 摘要 |
<p>In the 2-stage (co)polymerisation of olefines, the catalyst is obtained by reducing a transition metal compound with an organomagnesium compound, and is activated by an organometallic compound. Polymerisation is in 2 stages in the same or separate polymerisation zones; the polymer in the reaction mixture at the end of the first stage is present also in the second stage reaction mixture. The conditions are such that the polymer removed from the second zone is a mixture of polymers formed in the first and second zones, with viscosity indexes of 0.2-4 or 3-20, in such amounts that the desired polymer product has a flow parameter of 1.4-2.5. The products have a wide mol. wt. distribution, giving improved preocessability. The necessity for extracting residual catalyst from the polymer is avoided. The reactors remain clean during prolonged operation. The polymers are particularly suitable for manufacturing bottles by blow-moulding.</p> |
