| 摘要 |
FIELD: polymerization processes. SUBSTANCE: process is accomplished on two in series connected polymerization reactors. In the first reactor, ethylene is polymerized in the form of suspension in medium including diluent, hydrogen, transition metalbased catalyst, and cocatalyst to give 30-70 % (of the total weight of composition) of ethylene homopolymer with fluidity index between 5 and 1000 g/10 min. Reaction medium containing this homopolymer is discharged from reactor and subjected to throttling to remove at least part of hydrogen. Degassed reaction medium, ethylene, and alpha-olefin comonomer, in particular 1-hexene, are introduced into second reactor to perform suspension polymerization giving 30- 70% (of the total weight of composition) of ethylene copolymer with fluidity index between 0.01 and 2 g/10 min. Hydrogen-to-ethylene molar ratio in the first reactor ranges from 0.05 to 1 and in the second reactor from 0.001 to 0.1. Molar ratio of hexene to ethylene in diluent in the second reactor ranges from 0.05 to 3. Resulting composition is characterized by HLMI fluidity index preferably at least 2 g/10 min. Also claimed are ethylene polymer composition and hoses. EFFECT: enhanced process efficiency. 10 cl, 6 tbl, 10 ex |
