摘要:
The invention provides a film of a polyethylene produced by polymerization catalysed by a single site catalyst and comprising as comonomers to ethylene at least two C 4-12 alpha olefins, preferably but-1-ene and hex-1-ene.
摘要:
A film with a broad molecular weight distribution, excellent impact strength and a high dart drop value or moderate dart drop value accompanied by good optical property consisting of a bimodal terpolymer comprising a low molecular weight homopolymer of ethylene and a high molecular weight terpolymer of ethylene, 1-butene and a C6 to C12 alpha-olefin, or a bimodal terpolymer comprising a low mo-lecular weight polymer which is a binary copolymer of ethylene and a C4 to C12 alpha-olefin and a high molecular weight polymer which is either a binary copolymer of ethylene and 1-butene, if the low molecular weight polymer is a binary co-polymer of ethylene and a C6 to C12 alpha-olefin, or a terpolymer of ethylene, l-butene and a C6 to C12 alpha-olefin.
摘要:
Metallocenes and catalyst systems for olefin polymerization derived therefrom. The metallocenes may be represented by the formula: (I), wherein M 1 preferably is zirconium or hafnium; and R 5 is different from hydrogen.
摘要:
Linear low density polyethylenes (LLDPEs) that have relatively high melt index ratios (MIR) and relatively high melt strength (MS) are described. This combination of melt properties is achieved by a substantially non-blended LLDPE. Catalysts used to produce these polyethylenes are generally a blend of bridged bisindenyl zirconocene dichlorides, where one zirconocene contains saturated indenyls and the other unsaturated indenyls.
摘要:
Polymers of propylene with one or two olefin comonomers are produced through the use of a poymerisation catalyst supported on a carrier produced by spray crystallisation and having a maximum dimension of μm. Copolymers of superior properties are obtained, and the production process is de-snagged.
摘要:
Polymers made by transition metal catalyst systems comprising a bulky noncoordinating anion (NCA) as cocatalyst component. In comparison to polymers containing a conventional NCA, these polymers show a considerably lower dielectric loss, making them suitable for insulation applications such as for power cable.
摘要:
A wrapping film and shrink film which are formed from a resin composition comprising a 1−butene polymer satisfying the following requirements (1) to (4) and an olefin polymer. It is a crystalline resin having a melting point (Tm−D) as measured with a differential scanning calorimeter (DSC) of 0 to 100°C (provided that this "melting point" is defined as the peak top of the peak observed on the highest−temperature side in a melting endothermic curve obtained by holding a sample in a nitrogen atmosphere at −10°C for 5 minutes and then heating it at a rate of 10 °C/min). The stereoregularity index {(mmmm)/(mmrr+rmmr)} is 20 or lower. The molecular weight distribution (Mw/Mn) as determined by gel permeation chromatography (GPC) is 4.0 or lower. The weight−average molecular weight (Mw) as determined by GPC is 10,000 to 1,000,000.
摘要:
Polymers made by transition metal catalyst systems comprising a bulky noncoordinating anion (NCA) as cocatalyst component. In comparison to polymers containing a conventional NCA, these polymers show a considerably lower dielectric loss, making them suitable for insulation applications such as for power cable.
摘要:
There is provided a process for the copolymerisation of propylene with at least one C 4-20 α-olefin or C 4-20 diene in a reaction medium in the presence of a catalyst system at a temperature of greater that 80 °C or at a temperature and pressure above the critical temperature and pressure of the reaction medium. Under such conditions, comonomer incorporation is higher than under standard conditions.
摘要:
The invention provides a process for the preparation of a propylene polymer in which propylene and a comonomer copolymerizable therewith and of greater molecular weight than propylene are polymerized in a single site catalyst catalized polymerization reaction,, characterised in that said polymerization reaction is effected at least in part at a temperature of at least 70° C.