摘要:
Polyethylene composition with improved swell ratio and mechanical properties, particularly suited for preparing blow-moulded articles, said composition having the following features: 1) density from 0.952 to 0.960 g/cm 3 ; 2) ratio MIF/MIP from 17 to 30; 3) Shear-Induced Crystallization Index SIC from 2.5 to 5.0.
摘要:
The invention relates to a method for drying and degassing polyolefins. The polymerisation matter leaving a polymerisation reactor is contacted with a degassing medium and relaxed at the same time. According to the invention, the monomer to be polymerised is used as the degassing medium. Said monomer flows through a relaxation container, especially in a cycle process, and is preferably enriched with ethylene or other low-boiling olefins in an amount ranging from 0 to 100 mol % in relation to the entire amount of the cycle gas. Polymerisation is carried out in the relaxation container in an amount of up to 10 % in relation to the entire polymerisation conversion.
摘要:
Method of preparing olefin polymers, which comprises the polymerization of at least one α-olefin in the presence of a hybrid catalyst to produce a polymer comprising at least a higher molecular weight polymer component and a lower molecular weight polymer component in the presence of water in an amount of from 2 to 100 mol ppm and/or carbon dioxide in an amount of from 2 to 100 mol ppm, in each case based on the total reaction mixture, in order to alter the ratio of the higher molecular weight polymer component to the lower molecular weight polymer component. This enables the ratio of the higher molecular weight component to the lower molecular weight component to be controlled selectively.
摘要:
The invention relates to a method for drying and degassing polyolefins. The polymerisation matter leaving a polymerisation reactor is contacted with a degassing medium and relaxed at the same time. According to the invention, the monomer to be polymerised is used as the degassing medium. Said monomer flows through a relaxation container, especially in a cycle process, and is preferably enriched with ethylene or other low-boiling olefins in an amount ranging from 0 to 100 mol % in relation to the entire amount of the cycle gas. Polymerisation is carried out in the relaxation container in an amount of up to 10 % in relation to the entire polymerisation conversion.
摘要:
The invention relates to a method for the polymerization of olefins in the presence of catalysts which contain at least one complex of a transition metal with a tridentate macrocyclic ligand, which in addition comprises at least one functional substituent, and optionally one or more activator compounds. The invention also relates to a catalyst system which comprises at least one of the transition metal complexes provided for in the invention and at least one activator compound.
摘要:
The invention relates to a low odor polyethylene blend containing a high molecular ethylene polymer obtained by polymerization in the presence of a Ziegler catalyst and a low molecular ethylene homopolymer or copolymer obtained by polymerization in the presence of a chromocene catalyst on an oxidic support. The invention is characterized in that the Al content of the high molecular components is 5 to 60 mg/kg, the Al content of the of the low molecular components is 0 to 5 mg/kg and the Al content of the blend is 1 to 55 mg/kg. The invention also relates to a method for the production of said blend, to the use thereof in the production of shaped bodies, especially hollow bodies and tubes, and to shaped bodies, especially hollow bodies and tubes manufactured from low odor polyethylene blends.
摘要:
The invention relates to a method for producing highly branched ethylene polymers. Said method is characterised in that ethylene is polymerised by means of a catalyst system containing a compound of formula (Ia) or (Ib) and an activator. The inventive method is carried out at a temperature of between 40 and 110 °C and at a pressure of between 10 and 100 bar.