| 摘要 |
Polymers of ethylene alone or with another monomer are made in the form of films, by polymerizing the monomer or monomers in the presence of a catalyst consisting of an organo-metallic compound of Group I, II, and III of the Periodic Table and a transition metal compound, on a liquid surface of a liquid reaction medium throughout which the catalyst is distributed, and which has no solvent effect on the polymer formed at the polymerization temperature. The Specification contains an extensive list of monomers which may be copolymerized with ethylene. The monomers may be selected from alpha mono-olefines, non-conjugated dienes such as dicyclopentadiene or 1, 4-hexadiene, 5-alkenyl-substituted-2-norbornenes, 5-methylene-2-norbornene, or 2-alkyl-2, 5-norbornadienes. The Specification also contains long lists of two and three component catalysts. Polymers exemplified are polyethylene and copolymers of ethylene and propylene, and terpolymers ethylene, propylene, and 1, 4-hexadiene. The exemplified catalyst is a mixture of vanadium tris (acetyl-acetonate) and diisobutyl aluminium monochloride which may be made by reacting triisobutyl-aluminium and aluminium chloride. The liquid reaction medium may be methylene chloride, ethyl chloride, or 1,2-dichloroethylene. The monomers and solvents may be purified before use. The polymerization is effected in the absence of oxygen. The polymerization of ethylene and other gaseous monomers is effected by passing the monomers over the liquid surface. When a liquid monomer is used as a comonomer it may be dissolved or dispersed in the liquid reaction medium. The catalysts may be preformed or formed in situ. The polymer may be recovered as a coherent film, or scraped off by a doctor knife technique. Elastomeric polymers can be mill dried. Specification 778,639 is referred to.
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