摘要:
The present invention relates to a middle-pressure polymerization process for the preparation of a liquid ethylene copolymer which comprises in polymerized form 20 to 60 wt % of ethylene; and at least 20 wt % of an acrylate, which is selected from C1-C22 alkyl (meth)acrylate, where a monomer mix comprising the ethylene and the acrylate is polymerized at a pressure of 50 to 400 bar and in the presence of at least 2 wt % of a chain transfer agent. The invention further relates to a liquid ethylene copolymer obtainable by the polymerization process; and to a lubricant comprising the liquid ethylene copolymer obtainable by the polymerization process; and to a method for reducing friction between moving surfaces comprising the step of contacting the surfaces with the lubricant or with the ethylene copolymer.
摘要:
This disclosure relates to an improved continuous solution polymerization process wherein production rate is increased. Process solvent, ethylene, optional comonomers, optional hydrogen and a bridged metallocene catalyst formulation are injected into a first reactor to form a first ethylene interpolymer. Optionally, process solvent, ethylene, optional comonomers, optional hydrogen and a bridged metallocene catalyst formulation are injected into a second reactor forming a second ethylene interpolymer. The first and second reactors may be configured in series or parallel modes of operation. Optionally, a third ethylene interpolymer is formed in a third reactor, wherein a homogeneous catalyst formulation or a heterogeneous catalyst formulation is employed. In solution, the first, optional second and optional third ethylene interpolymers are combined, the catalyst is deactivated, the solution is optionally passivated and following a phase separation process an ethylene interpolymer product is recovered.
摘要:
Novel copolymers having a density (D) in the range 0.895-0.910 g/cm3, a melt index MI2 (2.16 kg, 190° C.) in the range of 0.01-6 g/10 min, a Compositional Distribution Branch Index (CDBI) in the range 55-85%, and a sealing initiation temperature (SIT) and density (D) satisfying the relationship SIT≤(A×D)−B wherein A is 800° C.×cm3/g and B is 650° C., wherein the SIT (° C.) is determined on a 70 μm film at 0.5N/15 mm and D Is in units of g/cm3 are disclosed. The copolymers may be suitably prepared by use of metallocene catalyst systems and may be used in film applications, in particular as sealing layers for packaging applications.
摘要:
Provided herein are VLDPE polymer compositions suitable for use in the manufacture of flexible films or sheets. In one embodiment, the copolymer comprises a polyethylene VLDPE resin with Mz/Mw of greater than 2, CDBI50 of greater than 55 and a single melting peak in DSC measurement. The polymer compositions disclosed herein may be suitable for use in the manufacture of films with improved balance of film toughness, processability and sealability in monolayer and multi-layer film structures.
摘要:
Some embodiments herein disclose a process for producing an ethylene polymer or copolymer which contains less than 5 ppm titanium and has a bulk density, in granular form, of at least 22.5 lbs/ft3, using a spheroidal Ziegler-Natta type olefin polymerization catalyst having a particle size distribution characterized by a Dm*/Dn of less than 3.0 and comprising a titanium compound, an aluminum compound, and a spheroidal magnesium chloride support.
摘要翻译:本文的一些实施方案公开了使用球形齐格勒 - 纳塔型烯烃聚合催化剂制备乙烯聚合物或共聚物的方法,该方法包含小于5ppm的钛并且具有至少22.5lbs / ft 3的颗粒形式的堆积密度,所述催化剂具有 粒径分布的特征在于Dm * / Dn小于3.0,并包含钛化合物,铝化合物和球形氯化镁载体。
摘要:
A copolymer obtained by polymerizing two or more types of monomers, wherein among fractions obtained by dividing an eluate showing peaks relative to the copolymer, in an elution curve obtained by gel permeation chromatography (GPC), into eight fractions in order of fractionation, such that each fraction has the same volume, a difference between a monomer composition ratio of a copolymer contained in a first eluted fraction and a monomer composition ratio of all copolymers is −3 mol % to +3 mol % in any of the constitutional units derived from the respective monomers.
摘要:
The instant invention provides an ethylene/alpha-olefin interpolymer suitable for use in shrinkage film applications, and articles made therefrom. The ethylene/alpha-olefin interpolymer according to the present invention has a CDBI of less than 60%, and comprises at least two fractions in crossfractionation of the ethylene/alpha-olefin interpolymer, eluting from 85° C. to 90° C. and from 90° C. to 95° C., comprising a weight fraction ratio of >0.68 and a molecular weight homogeneity index of greater than 0.65; wherein the weight fraction ratio is the ratio of the weight of polymer in each fraction divided by the weight of polymer eluting between 95° C. and 100° C. and the molecular weight homogeneity index is the ratio of the weight average molecular weight of the polymer in the fraction divided by the weight average molecular weight of the polymer eluting between 95° C. and 100° C., and wherein the ethylene/alpha-olefin interpolymer has a density in the range of 0.920 to 0.940 g/cm3.
摘要:
The present invention relates to a process for the production of propylene copolymers wherein in a first step an olefin polymerisation catalyst comprising a solid catalyst component is subjected to a prepolymerisation reaction in a prepolymerisation reactor, in which propylene monomers are present in an amount of 98.0 to 99.9 mol % and further alpha-olefin monomers other than propylene are present in an amount of 0.1 to 2.0 mol %, based on the combined amount of propylene and further alpha-olefin monomers, so that a prepolymer is produced on the catalyst in an amount of 10 to 1000 g per g of the solid catalyst component, and in a second, subsequent step propylene and further alpha-olefin monomers other than propylene are copolymerised in the presence of the prepolymerised catalyst produced in the first step so that a propylene copolymer is obtained which contains at least 0.1 mol % of alpha-olefin units other than propylene, to propylene copolymers obtainable by such a process and to the use of a prepolymerised catalyst in such a process.
摘要:
The present invention relates to a continuous process for producing polymers at conversions ranging from 50% to 95% having a Mooney viscosity of at least 25 Mooney-units and a gel content of less than 15 wt. % containing repeating units derived from at least one isoolefm monomer, more than 4.1 mol% of repeating units derived from at least one multiolefm monomer and optionally further copolymerizable monomers in the presence of AlCl3 and a suitable proton source (e.g. water) or cationogen and at least one multiolefin cross-linking agent wherein the process is conducted in the absence of transition metal compounds and organic nitro compounds.