摘要:
A shrink film comprising a polyethylene film, characterized in that said polyethylene is an ethylene copolymer mixture having a molecular weight distribution in the range 10 to 35, a density of 915 to 940 kg/m3, a weight average molecular weight of at least 100000 D and an MFR2.16 (190° C.) of 0.1 to 0.9 kg/m3, which copolymer mixture is produced by a two or more stage copolymerization of ethylene and 2 to 10% mole (relative to ethylene) of a C3-12 alpha-olefin comonomer in a series of reactors including at least one slurry loop reactor and at least one gas phase reactor using a heterogeneous Ziegler-Natta catalyst.
摘要翻译:一种包含聚乙烯膜的收缩膜,其特征在于所述聚乙烯是分子量分布在10至35,密度为915至940kg / m 3,重均分子量至少为100000D的乙烯共聚物混合物 并且MFR2.16(190℃)为0.1至0.9kg / m 3,该共聚物混合物通过乙烯和2-10%摩尔(相对于乙烯)的C3-12α的两个或多个阶段共聚制备 烯烃共聚单体在一系列反应器中,包括至少一个淤浆环流反应器和至少一个使用异质齐格勒 - 纳塔催化剂的气相反应器。
摘要:
A shrink film comprising a polyethylene film of thickness 5 to 500 μm, wherein the polyethylene comprises an ethylene homopolymer-copolymer mixture having a molecular weight distribution in the range of 5 to 40, and a weight average molecular weight of at least 100 kD.
摘要:
The present invention provides a uniaxially oriented multilayer film comprising at least (i) a layer (A) and (ii) a layer (B), wherein said layer (A) comprises a linear low density polyethylene (LLDPE) comprising (e.g. selected from):—a multimodal LLDPE produced using a Ziegler Natta catalyst (znLLDPE), or—a LLDPE produced using a single site catalyst (mLLDPE) or—a mixture of a mLLDPE and a multimodal znLLDPE, said layer (B) comprises a multimodal LLDPE, and said multilayer film is in the form of a stretched film which is uniaxially oriented in the machine direction (MD) in a draw ratio of at least 1:3.
摘要:
The present invention provides a uniaxially oriented multilayer film comprising at least (i) an outer layer (B) and (ii) an inner layer (C), wherein said layer (B) (i) comprises a multimodal linear low density polyethylene (LLDPE), said layer (C) (ii) comprises at least one polymer component which has a Tm
摘要:
This invention concerns process for producing polyethylene compositions, films prepared thereof and process for the preparation of the films. The process comprises subjecting ethylene, optionally hydrogen and comonomers to polymerization or copolymerization reactions in a multistage polymerization. At least one polymerization stage is conducted essentially in the absence of hydrogen. The polymerization reactions are carried out in the presence of a single-site catalyst capable of forming a composition comprising a low molecular weight component with MFR2 of at least 10 g/10 min and a density higher than the density of the composition and a high molecular weight component. The melt flow rate of the composition is in the range MFR2=0.1-5.0 g/10 min and the density of the composition is 915-960 kg/m3. The invention makes it possible to produce polyethylene compositions for manufacturing films with a good balance between optical and mechanical properties.
摘要:
The present invention relates to a blown film made of a composition comprising a) a propylene heterophasic copolymer (A) with a matrix propylene polymer and an ethylene-propylene-rubber characterized in that the film has been monoaxially oriented in the machine direction with a stretch ratio of 1:1.1 to 1:10, to a process for making such a film, to the use of said composition in making such a film, and to an article comprising such a film.
摘要:
A process for producing bimodal linear low-density polyethylene polymer compositions, useful for making films. The polymer compositions have a melt flow rate MFR2 of 0.4 to 1.0 g/10 min and a density of 918 to 925 kn/m3. The process to produce the polymer compositions involves copolymerizing ethylene with an alpha-olefin comonomer in a loop reactor to produce a low molecular weight polymer having a melt flow rate MFR2 of 50 to 500 g/10 min and a density of 945 to 953 kg/m3. The polymerization is continued in a gas phase reactor to produce a high molecular weight polymer, such that the final polymer composition has the desired properties. The final composition contains from 41 to 48% by weight of the low molecular weight polymer and from 59 to 52% by weight of the high molecular weight polymer. The resulting films have an excellent visual appearance and good mechanical properties. The compositions can easily be converted to films. The process can be operated a long time without a shutdown.
摘要:
The present invention concerns a process for producing homogeneous polyethylene compositions and processes for making high density, medium density and low density films therefrom. The process comprises carrying out the polymerization in the presence of an ethylene-polymerizing catalyst system in a multistage reaction sequence of successive polymerization stages, at least one of which is a loop polymerization stage, and at least one of which is a gas phase polymerization stage. According to the invention, said loop polymerization stage is operated using a diluent selected from the group of linear and branched C4-C6 hydrocarbons and/or mixtures thereof. The reactor sequence is operated with different amounts of hydrogen and comonomers to produce a high molecular weight portion in one of the polymerization stages and a low molecular weight portion in another, so as to provide bimodal polyethylene composition with a low molecular weight part having an MFR2 of 250 g/10 min or more. The obtained material is homogenous and the fines level in the process is low.