MXPA97002029A - Ethylene polymers that have superior clarity, improved tenacity, low content of removable materials and ease of processing - Google Patents

Abstract

The present invention relates to provide polymers of ethylene having a Polydispersity Index of about 2 to about 4, a melting index;; MI, and a Relaxation Spectrum Index, RSI, such that (RSI) (MI0. 6) is from about 2.5 to about 6.5, c) a Crystallizable Chain Length Distribution Index, Lw / Ln, from about 1.0 to about 9, and d) a density, p, and a percentage of turbidity when manufactured in films in such a way that the percentage of turbidity is less than 370p - 330. These ethylene polymers advantageously combine superior clarity and toughness with a low content of extractables and ease of processing improvement

Description

"ETHYLENE POLYMERS THAT HAVE SUPERIOR CLARITY, IMPROVED TENACITY, LOW CONTENT OF REMOVABLE MATERIALS AND EASE OF PROCESSING" This request is a continuation in part of the US Application Serial Number 08 / 412,964, filed March 29, 1995. This invention relates to ethylene polymers having a limited molecular weight distribution and limited composition distribution which are also easy to process with time distribution of Relatively limited relaxation. Manufactured articles made from these ethylene polymers have excellent clarity and tenacity, as well as low extractable material content.

BACKGROUND OF THE INVENTION Wide attention has been given to metallocene catalysts because of their ability to produce ethylene polymers having relatively limited molecular weight and comonomer distributions to excellent polymerization regions. These limited molecular weight and comonomer distributions contribute to improvements in clarity, toughness and levels of extractable materials in ethylene polymers having densities much lower than 0.95 gram per cubic centimeter. However, for some applications that require processability, such as extrudability, these ethylene polymers can be defined due to their limited molecular weight distributions. For example, U.S. Patent Nos. 5,420,220 and 5,324,800, disclose linear low density polyethylenes made from metallocene having characteristic critical molecular weight and comonomer distributions, together with associated limitations in processability. Unfortunately, if the molecular weight distribution of an ethylene polymer is enlarged in order to improve processability, the clarity and impact resistance of the polymer decrease. In addition, the extractable materials increase, especially for ethylene polymers that have much lower densities of 0.93 gram per cubic centimeter. To improve the processability of an ethylene polymer, while maintaining a limited molecular weight distribution, long chain branching can be incorporated into the polymer. For example, U.S. Patent Nos. 5,272,236 and 5,278,272, and PCT Application Number WO94 / 07930 describe very low density, low density polyethylene made with metallocene having long chain branching structures and which are disclosed as having processability improved However, long chain branching structures sometimes promote or activate directional orientation during manufacturing, leading to an imbalance in mechanical properties and reduced impact and breakage resistance. The clarity of manufactured articles such as blown film may also be less than optimal for long chain branched ethylene polymers even with limited molecular weight and comonomer distributions. Applicants have identified a family of ethylene polymers having a limited molecular weight distribution and limited compositional distribution compared to conventional linear low density polyethylene made from Ziegler-Natta catalysts. Surprisingly, however, ethylene polymers also have a relatively limited relaxation time distribution, defined by their Relaxation Spectrum Index (RSI), such that the processability of ethylene polymers is comparative, at a rate of fusion similar to conventional linear low density polyethylenes made with Ziegler-Natta catalysts, which have - - broader molecular weight distributions and are superior to many polyethylenes made with commercial metallocene. The film articles made of ethylene polymers present are characterized by superior clarity, greater impact resistance (e.g., arrow impact) and low content of extractable materials. Similarly, injection molded articles made from the ethylene polymers present have improved clarity and tenacity (e.g., low temperature properties and ESCR) as characterized by higher impact strength compared to polyethylenes of known linear low density. The improved toughness associated with the ethylene polymers of the applicant offers a potential for film thickness reduction and "thin masonry" of the molded part, while retaining sufficient strength. In addition, ethylene polymers provide superior performance in high volume film applications, such as elongation, high clarity and other packing films. And because of the low content of extractable materials of the ethylene polymers present, the film and molded articles produced therefrom are attractive for use in the food packaging market.

- - SUMMARY OF THE INVENTION The invention provides an ethylene polymer having: a) a Polydispersity index of from about 2 to about 4; b) a melt index, MI, and a Relaxation Spectrum Index, RSI, such as (RSI) (MIu-6) which is from about 2.5 to about 6.5; c) a Crystallizable Chain Length Distribution Index, Lw / Ln, from about 1 to about 9; and d) a density, p, and a percentage of turbidity when manufactured in a film such that the haze percentage is less than 37Op -330. The invention also relates to an ethylene polymer prepared by contacting the ethylene and optionally a higher alpha-olefin under polymerization conditions with a catalyst composition in unsupported liquid form, the catalyst composition comprising a transition metal catalyst which essentially does not produces long chain branching.

DETAILED DESCRIPTION OF THE INVENTION - - The ethylene polymers of the invention include homopolymers of ethylene and interpolymers of ethylene and higher linear or branched alpha-olefins containing from 3 to about 20 carbon atoms, with densities ranging from about 0.90 to about 0.95 and melting rates of about 0.1 to 200. Suitable higher alpha-olefins include, for example, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 3, 5, 5-trimethyl-1. -hexeno. Cyclic olefins such as vinyl cyclohexane and norbornene can also be polymerized with ethylene. Aromatic compounds having vinyl unsaturation, such as styrene and substituted styrenes, can also be included as comonomers. Particularly preferred ethylene polymers comprise ethylene and from about 1 percent to about 40 percent by weight of one or more comonomers described above. The ethylene polymers have uncorrected polydispersity indices for long chain branching of from about 2.0 to about 4.0, preferably from about 2.5 to about 3.5. The Polydispersity Index (PDI) of a polymer is defined as the ratio of the weight average molecular weight of the polymer to the number average molecular weight of the polymer (Mw / Mn). The PDI, uncorrected for long chain branching, is determined using size exclusion chromatography (SEC) with an ATERS 150C GPC instrument operating at 140 ° C with 1,2,4-trichlorobenzene at a flow rate of 1 milliliter. per minute. The pore size scale of the column set provides separation "ie MW that covers the scale of 200 to 10,000,000 Daltons. The National Institute of Standards Technology of the NBS 1475 or 1496 polyethylene standard is used as the calibration standard to obtain the uncorrected molecular weight distribution (assumed linear polymer). The ethylene polymers present have unique rheological properties that suggest a molecular structure distinct in part in superior toughness in manufactured articles. These unique rheological properties also favor the ease of relative manufacture in finished articles, especially in film extrusion. In particular, ethylene polymers have MI melt indexes and Relaxation Spectrum Indexes, RSI, in such a way, for a given ethylene polymer: of about 2.5 < (RSI) (MI0 * 6) < to approximately 6.5.

Preferably from about 3.0 < (RSI) (MI? - >) < at approximately 5.0.

In the formulas provided immediately above, the MI is the melt index of the polymer disclosed as grams per 10 minutes, which is determined according to the D-1238 method of the American Society for the Testing of Materials, condition E, at 190 ° C, and the RSI is the Index of the Relaxation Spectrum of the polymer in units exempt from dimesion. The RSI of the ethylene polymer is determined by first subjecting the polymer to a shear strain and measuring its response to deformation using a rheometer. As is already known in the art, based on the response of the polymer and the mechanics and geometry of the rheometer used, the relaxation module G (t) or the dynamic modules G '(omega) and G "(omega) can be determined as functions of time to omega frequency, respectively (see JM Dealy and KF Wissbrun, Melt Rheology and Its Role in Plastics Processing, Van Nostrand Reinhold, 1990, Pages 269-297). The mathematical connection between the dynamic and storage modules is an integral Fourier transformation relationship but one set of data can also be calculated from another using the well-known relaxation spectrum (see SH Wasser an, J. Rheology, Volume 39, Pages 601 a 625 (1995)). Using a classical mechanical model, a spectrum of discrete relaxation can be defined consisting of a series of relaxations or "modes", each with a characteristic intensity or "weight" and time of <-5 Relaxation. Using that spectrum, the modules are re-expressed as: N G (0 =? GiexpH /? I) where N is the number of modes and g¿ and 7 ^ are the weight and time for each of the modes (see J.D. Ferry, Viscoelastic Properties of Polymers, John Wiley &Sons, 1980, Pages 224-263). A relaxation spectrum can be defined for the polymer using software such as IRIS (R) rheological software, which can be obtained commercially from IRIS Development. Once the distribution of the modes in the relaxation spectrum is calculated, the first and second moments of distribution that are analogous to Mn and Mw, the first and second moments of the molecular weight distribution are calculated from the following way: 8li =? G¡? ¡/? G¡ i = l I i =? RSI is defined as gij j. Because RSI is sensitive to these parameters as a molecular weight distribution of the polymer, molecular weight and long chain branching, it is a sensitive and reliable indicator of the stress stress of a polymer. The higher the RSI value, the broader the polymer relaxation time distribution and, therefore, the better the processability of the polymer. In addition, the ethylene polymers have a Crystallizable Chain Length Distribution Index, Lw / Ln, of about 1 to about 9, preferably about 1 to about 6, indicating that they have relatively limited comonomer distributions and, therefore, , homogeneity of relative composition. The Crystallizable Chain Length Distribution Index was determined using Tempera Elevation Elution Fractionation (TREF), as described in the article by Wild et al., J. Polymer Sci. Poly. Phys. Ed., Volume 20, Page 441, (1982). A dilute solution of ethylene polymer in a solvent such as 1, 2, 4-trichlorobenzene, at 1 to 4 milligrams per milliliter, is loaded at high tempera into a packed column. The column is then allowed to cool slowly to 0.1 ° C per minute to room tempera in a controlled manner so that the ethylene polymer crystallizes towards the packing in the order of increased branching (or decreased crystallinity) with decreasing tempera. The column is then heated in a controlled manner at 0.7 ° C per minute to more than 140 ° C with a constant solvent flow of 2 milliliters per minute through the column. Fractions of the polymer as they elute, have a decreasing branching (or increasing crystallinity) with increased tempera. An infrared concentration detector is used to monitor the concentrations of the effluent. From the TREF tempera data, the branching frequency can be obtained for a given comonomer. Consequently, the main chain lengths between the branches that are expressed as Lw and Ln, can be calculated in the following manner. Lw is the average chain length in weight between branches: 'w ~ iwiLi - - and Ln is the average chain length in number between the branches: L Jnn = = 11 / T £ idvi / L), wherein w 'is the weight fraction of the component of the polymer i having a separation L of the average basic struc chain between two adjacent branch points. The ethylene polymers present have low idity when formed in films, indicating a clarity greater than a determined polymer density. In particular, ethylene polymers have a haze percentage when they are in the form of a film and of a density such that, for a given ethylene polymer:% idity < (370p - 330), where p is the density of the polymer. Preferably% idity < (370p - 335). The density is measured according to test method D1505 (G-101) of the American Society for the Testing of Materials. The idity percentage measurement is carried out according to test method D1003 of the American Society for the Testing of Materials, which measures the transmitted light that, when passing through the specimen, is - - diverts from the incident beam by direct scattering. For purposes of this test method, only the light flux that deviates by more than 2.5 ° on average is considered to be turbidity. The catalyst compositions which can be used to produce ethylene polymers of the invention, are in unsupported liquid form and comprise G- transition metal catalysts which essentially do not produce long chain branching, preferably no branching: long chain. These transition metal catalysts include compounds comprising transition metal complexes, substituted or unsubstituted //-linked coordinator groups and heteroalyl residues, such as those described in the Application of copending US Patent Serial No. 08 / 412,964, filed March 29, 1995. Preferably, these compounds have one of the following formulas: - - wherein: M is a transition metal, preferably Zr or Hf; L is a coordinated / -ligated substituted or unsubstituted group coordinated with M, preferably a cycloalkadienyl coordinating group; each Q is independently selected from the group consisting of -0-, -NR-, -C 2- and -S-, preferably oxygen; And it is either C or S, preferably carbon; Z is selected from the group consisting of -OR, -NR2, -CR3, -SR, -SIR3, -PR2 and ~H, with the proviso that when Q is -NR-, then Z is selected from the group consisting of -OR, -NR2, -SR, -SIR3, -PR2 and -H, preferably Z is selected from the group consisting of -OR, -CR3 and -NR2. n is 1 or 2; A is a univalent anionic group when n is 2 or A is a divalent anionic group when n is 1, preferably A is a carbamate, carboxylate or other heteroalyl residue which is described by a combination of Q, Y and Z; and each R is independently a group containing carbon, silicon, nitrogen, oxygen and / or phosphorus, wherein one or more of the R groups can be attached to the substituent L, preferably R is a hydrocarbon group containing from 1 to 20 carbon atoms, more preferably an alkyl, cycloalkyl or an aryl group and one or more may be attached to the substituent L. where: M is a transition metal, preferably Zr or Hf; L a coordinated / -ligado substituted or unsubstituted group coordinated with M, preferably a cycloalcadienyl coordinating group; each Q is selected independently from the group consisting of -O-, -NR-, -CR2- and -S-, preferably oxygen; And it is either C or S, preferably carbon; Z is selected from the group consisting of -OR, -NR2, -CR3, -SR, -SIR3, -P2, and -H, with the proviso that when Q is -NR, then Z is selected from the group consisting of -OR, -NR;?, -SR, -SIR3, -PR2 and -H, preferably Z is selected from the group consisting of -OR, -CR3 and -NR2; n is 1 or 2; A univalent anionic group when n is 2 and A is a divalent anionic group when n is 1, preferably A is a carbamate, carboxylate or other heteroalyl residue residue described by the combination of Q, Y and Z; each R is independently a group containing carbon, silicon, nitrogen, oxygen and / or phosphorus wherein one or more of the R groups can be attached to the substituent L, preferably R is a hydrocarbon group containing from 1 to 20 carbon atoms. carbon, more preferably an alkyl, cycloalkyl or an aryl group and one or more can be attached to the substituent L; T is a bridging or connection group that is selected from the group consisting of alkylene and arylene groups containing from 1 to 10 carbon atoms optionally substituted with carbon or heteroatoms, germanium, silicone and alkylphosphine, and m is from 1 to 7, preferably from 2 to 6, particularly preferably 2 or 3.

- Particularly preferred compounds comprising transition metal complexes, substituted or unsubstituted 77-linked coordinate groups and heteroalyl residues, are the indenyl-zirconium tris (diethylcarbamate) and indenyl-zirconium tris (pivalate). Other transition metal catalysts that may be used to prepare the ethylene polymers are those derived from the coordination complexes of bis- and tri- cyclopentadienyl mono- and not connected with a transition metal, such as those described in the Patents North American Numbers 4,542,199, 5,324,800 and European Patent 250,601-B1, which essentially do not produce or preferably do not produce long chain branching in ethylene polymers. Examples of these catalysts are bis (cyclopentadienyl) zirconium dichloride and bis (cyclopentadienyl) zirconium diphenoxide. The catalysts are used together with activating cocatalysts such as aluminoxanes, ie, methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), or boron alkyls, to form the unsupported liquid catalyst compositions for the production of the polymers of ethylene. Aluminoxanes are preferred cocatalysts and their method of preparation and use is well known in the art.

- - The catalyst compositions used to produce the ethylene polymers must be introduced into the reaction zone in unsupported liquid form as described in U.S. Patent No. 5,317,036. As used herein, the term "unsupported liquid form" includes a liquid catalyst, a liquid cocatalyst, a catalyst (s) solution (s). cocatalyst in a same or different solvent (s), and combinations thereof. In addition to its ability to To prepare the ethylene polymers present having advantageous properties, the soluble catalyst compositions have a number of additional practical benefits. The unsupported catalyst compositions avoid the costs associated with the support material and its preparation, and provide obtaining a very high catalyst surface area with respect to the volume ratio. In addition, unsupported catalyst compositions produce polymers that have a much lower residual ash content than polymers produced using supported catalyst compositions. The ethylene polymers can be made by any polymerization process of suspension, solution, slurry or conventional gas phase, using well-known reaction conditions in the - technique. A reactor or several reactors can be used in series. Gas phase polymerization is preferred using one or more fluidized bed reactors. The polymerization is preferably carried out in the gas phase in a fluidized bed or stirred reactor using equipment and procedures well known in the art. Preferably, super atmospheric pressures are used within the range of .0703 to 70.30 kilograms per square centimeter, preferably from 3.51 to 28.12 kilograms per square centimeter, and especially preferably from 7.03 to 21.09 kilograms per square centimeter and temperatures within the scale from 30 ° to 130 ° C, preferably from 65 ° to 110 ° C. If used, the ethylene and other monomers are contacted with an effective amount of the catalyst composition at a temperature and pressure sufficient to initiate the polymerization. Suitable gas phase polymerization reaction systems comprise a reactor to which the monomer (s) and the catalyst composition can be added and which contain a bed to form polyethylene particles. The invention is not limited to any specific type of gas phase reaction system. As an example, a conventional fluidized bed process is carried out by passing a gaseous stream containing one or more monomers continuously through a fluidized bed reactor under reaction conditions, and in the presence of a catalyst composition at a sufficient rate to maintain the bed of solid particles in a suspended condition. The gaseous stream containing the unreacted gaseous monomer is continuously removed from the reactor, compressed, cooled, optionally condensed partially or completely recycled to the reactor. The product is removed from the reactor and the replenishing monomer is added to the recycle stream. Conventional additives may be included in the process, as long as they do not interfere with the operation of the catalyst composition. When hydrogen is used as a chain transfer agent in the process, it is used in amounts ranging from about 0.001 to about 10 moles of hydrogen per mole of the total monomer feed. Also, as desired for the temperature control of the system, any inert gas in the catalyst composition and the reagents may also be present in the gas stream. The organometallic compounds can be used as purification agents for contaminants in order to increase the activity of the catalyst. The examples of - - these compounds are metal alkyls, preferably aluminum alkyls, more preferably triisobutyl aluminum and tri-n-hexyl aluminum. The use of these scavenging agents is well known in the art. The ethylene polymers can be mixed with other polymers and resins as desired, using techniques known in the art. In addition, various additives and reagents can be mixed with the ethylene polymers. Specifically, additional thermo- and photo-oxidation stabilizers including hindered phenolic antioxidants and hydroxy ino, hindered amine light stabilizers, thioesters or disulfides and aryl phosphites or phosphonites can be added of course. To meet the specialized product requirements, crosslinking agents including dicumyl peroxide, dyes including carbon blacks and titanium dioxide, lubricants including metal stearates, processing aids including fluoroelastomers, slip agents including oleamide or erucamide, anti-blocking agents including stearamide, ethylene bis-stearamide, zeolite of controlled particle size, calcium carbonate, talc or silica, blowing agents, flame retardants and other conventional materials can be mixed with the ethylene polymer of the invention, as desired .

The ethylene polymers of the invention are useful for manufacturing in a variety of finished articles such as films including shrink film clarity films, extrusion coatings, insulation and wire and cable sleeves, crosslinked energy cable insulation, molded articles made by injection molding, blow molding or rotation molding, tube extrusions, tubing, profiles and sheets and sleeves and / or insulation and semiconductor shields. The methods for making these articles are well known in the art. The disclosures of the patents to which reference is made in the foregoing are incorporated herein by reference. The following non-limiting examples will further illustrate the invention.

EXAMPLES Measurements Molecular Weights and Molecular Weight Distribution were determined in the following manner. A WATERS 150C GPC chromatography apparatus equipped with mixed pore size columns for measurements of molecular weight was the apparatus employed. For chromatography of exclusion of - Size (SEC), a 25-centimeter-long preliminary column of Polymer Labs having a nominal pore size of 50 angstrom units was used, followed by three 25-centimeter long Shodex A-80 M / S columns (Showa) for effect molecular weight separation for a linear ethylene polymer of about 200 to 10,000,000 Daltons. Both columns contained a porous poly (styrene-divinylbenzene) packing. 1,2,4-Trichlorobenzene was used as the solvent to prepare the polymer solutions and the chromatographic eluent. All measurements were made at a temperature of 140 ° t 0.2 ° C. The analog signals of the mass and viscosity detectors were collected in a computer system. The collected data was then processed using standard software that can be obtained commercially from several sources (Waters Corporation and Viscotek Corporation) for uncorrected molecular weight distribution for the long chain branching. The calibration used the wide MWD calibration method and a linear polymer as the calibration material. (See W.W. Yau, J.J. Kirkland and D.D. Bly, Modern Size-Exclusion Liquid Chromatography, Wiley, 1979, pages 289-313). For the latter, two related MW statistics, such as MW values in number and average weight, should be known for the polymer calibration agent. Based on the calibration of - - MW, the elution volume is converted to molecular weight for the assumed linear ethylene polymer. Measures Rheological experiments were carried out through dynamic oscillatory shear stress experiments that were carried out with a new model of Weissenberg Rheogiometer that can be obtained commercially from TA Instruments. The experiments were carried out in a parallel plate mode under a nitrogen atmosphere at 190 ° C. The sample sizes vary from approximately 1100 to 1500 micrometers and were of a diameter of 4 centimeters. The frequency sweep experiments covered a frequency scale of 0.1 to 100 sec - 1 with a deformation amplitude of 2 percent. The torque response was converted by the TA Instruments rheometer control software into dynamic modules and dynamic viscosity data at each frequency. The discrete relaxation spectra were adjusted to the dynamic module data for each sample using the commercial software package IRIS (R). The TREF measurements were made as described above. The polymer melt index was reported as grams for 10 minutes, and was determined in accordance with Method D1238 of the American Society for the Testing of Materials, condition E. The density measurements were carried out in accordance with the - test method D1505 (G-101) of the American Society for the Testing of Materials. The turbidity was measured according to test method DI003 of the American Society for the Testing of Materials.

Examples 1 to 19 and A-N A series of ethylene polymers according to the invention (Examples 1 to 19) were compared with known polyethylene samples for a variety of properties, including Polydispersity Index (PDI), The Index of Crystallizable Chain Length Distribution (Lw / Ln), the Fusion Index (MI), the Spectrum Index of Relaxation (RSI), the percentage of turbidity, and density. The results are shown in the Table. The ethylene polymers in Examples 1 to 19 were made using a gas phase fluidized bed reactor, nominal diameter of 35.56 centimeters having a bed height of 3.05 meters. Each of the catalyst compositions in Examples 1 to 19 were in unsupported liquid form. The catalyst composition used to produce Examples 1 to 12 comprised an indenyl zirconium tris (diethylcarbamate) catalyst and a modified methylaluminoxane activation cocatalyst.

- - The catalyst composition used to produce each of Examples 13 to 17 comprised an indenyl zirconium tris (pivalate) catalyst and a modified methylaluminoxane activation cocatalyst. The catalyst composition used to produce Examples 18 and 19 comprised bis (cyclopentadienyl) zirconium dichloride and bis (cyclopentadienyl) zirconium diphenoxide, respectively, and a modified methylaluminoxane activation cocatalyst. Examples 9 to 12 were linear copolymers of ethylene and 1-butene, while Examples 1 to 8 and 13 to 19 were linear copolymers of ethylene and 1-hexene. Comparative Examples A and B were AFFINITY Polyolefin Plastomers which can be obtained commercially from The Dow Chemical Company, as specified in the Table. Examples C-H Comparison were EXCEED and EXACT linear ethylene polymers that can be obtained commercially from Exxon Chemical, as specified in the Table. Comparison Example I was a linear ethylene polymer obtainable commercially from BASF, as specified in the Table. Example J of Comparison was a linear copolymer of ethylene and 1-hexene also manufactured using a - - gas phase fluidized bed reactor of nominal diameter of 35.56 centimeters which has a bed height of 3.05 meters. The catalyst composition used to produce Comparative Example J comprised a bis (n-butyl-cyclopentadienyl) zirconium dichloride catalyst and a modified methylaluminoxane activation cocatalyst supported on silica. Examples K-N of Comparison, were commercial linear low density polyethylenes made through the UNIPOLAR process) (Union Carbide Corp.) using a gas phase fluidized bed reactor. There were ethylene polymers of 1-butene or 1-hexene and can be obtained commercially under the product designations HS 7093, HS 7037, HS 7028 and DFDA 9064. Comparison Example O was a linear copolymer of ethylene and 1-hexene manufactured similarly to Example 18, with the exception that the catalyst composition employed was bis (cyclopentadienyl) zirconium dichloride and an activating coctalizer of modified methylaluminoxane supported on silica. The ethylene polymers of the invention were each mixed dry with approximately 1500 parts per million of IRGANOX B-900 (Ciba-Geigy Corporation) and stirred in a Killion Extrusion apparatus of 3.81. centimeters with a length of screw mixer of LLDPE - normal (30/1 length to diameter) at a rate of 18.16 kilograms per hour (98 revolutions per minute). The granulated ethylene polymers of the invention and the polyethylenes of the Comparison Example were extruded into blown films using typical operating conditions with matrix temperatures and blow ratios as listed in the Table. The 'blowing ratio' is defined as the ratio of the final bubble diameter (tube) to the diameter of the matrix. He blown film extrusion equipment consisted of a 3.81 centimeter diameter Sterling extruder equipped with a general purpose LLDPE screw of 24: 1 L / D (constant tilt, decreased depth, mixing head screw) Maddox) and a spiral pin matrix. The blown film extrusion equipment was operated at a rate of 20.43 kilograms per hour (98 revolutions per minute).

TABLE Example MI 0.44 0.68 0.68 0.85 1.70 1.83 Density, 0.938 0.937 0.937 0.937 0.929 0.929 (gr / cc) PDI 3.47 2.78 2.78 2.66 2.70 2.52 Lw / Ln 8.90 5.31 5.31 4.13 7.24 5.88 RSI 5.7 3.6 3.6 3.1 2.2 5.6 Turbidity (%) 7.5 5.2 4.1 5.2 6.0 5.6 Extract. of Hexano 0.6 0.4 0.3 0.6 0.4 0.4 Fall of Arrow (gr) 50 50 50 50 77 73 Matrix Free Space (mm) 2.54 2.54 2.54 2.54 2.54 2.54 Fusing Temperature (° C) 260 260 235 232 192.5 193 Blowing Ratio 2.6 2.6 2.6 2.6 2.6 2.6 Head Pressure (kg / cm2) 179.3 154.7 186.3 165.2 138.9 154.7 Amperage 14.1 14.2 14.2 14.2 14.5 14.5 O 10 Matrix Regime (Kg / sec / cm) 418.3 431.1 411.8 431.1 450.5 463.3 A = 370p-335 14.27 13.94 13.94 13.79 10.78 10.93 B = RSI * MI? 0.6 3.47 2.85 2.85 2.81 3.03 3.04 Turbidity < Yes Yes Yes Yes Yes Yes 2. 5 < B < 6.5 Yes Yes Yes Yes Yes Yes 2 < PDI < 4 Yes Yes Yes Yes Yes Yes 25 1 < CCLDI < 9 Yes Yes Yes Yes Yes Yes - - TABLE Example 11 12 MI 1.99 2.29 1.23 1.41 1.66 1.67 Density, (gr / cc) 0.926 0.915 0.924 0.923 0.924 0.925 PDI 3.13 2.66 2.61 2.49 2.51 2.74 Lw / Ln 6.44 3.48 5.79 5.80 5.78 5.98 RSI 2.4 1.9 2.7 2.3 2.2 2.2 Turbidity (%) 3.6 3.0 7.2 7.4 6.4 8.6 Extract. of Hexano 2.6 1.2 0.4 0.6 0.5 0.4 Fall of Arrow (gr) 131 482 53 62 58 65 Matrix Free Space (mm) 2.54 2.54 2.54 2.54 2.54 2.54 Fusing Temperature (° C) 197.8 220 206 205.6 205.6 204 Blowing Ratio 2.6 2.6 2.6 2.6 2.6 2.6 Head Pressure (kg / cm2) 126.5 63.6 179.3 154.7 107.2 168.7 Amperage 13.8 9.5 15.0 14.8 14.6 15.1 Matrix Regime (Kg / sec / cm) 456.9 411.8 418.3 431.1 444 418.3 A = 370p-335 9.82 5.84 8.89 8.55 8.89 9.48 B = RSI * MI? 0.6 3.65 3.15 3.06 2.84 3.00 3.01 Turbidity < Yes Yes Yes Yes Yes Yes 2. 5 < B < 6.5 Yes Yes Yes Yes Yes Yes 2 < PDI < 4 Yes Yes Yes Yes Yes Yes 1 < CCLDI < 9 Yes Yes Yes Yes Yes Yes - - TABLE Example 13 14 15 16 17 18 MI 0.50 0.79 0.93 1.05 1.07 0.52 Density, (gr / cc) 0.937 0.922 0.920 0.916 0.929 0.920 PDI 2.70 2.89 3.04 2.96 2.62 2.87 Lw / Ln 6.57 8.58 8.11 7.61 7.55 1.78 RSI 4.1 4.6 4.1 4.2 3.3 6.3 Turbidity (%) 5.6 5.2 3.0 3.0 4.8 3.7 Extract. of Hexano 0.5 1.2 1.1 1.7 0.6 0.4 Fall of Arrow (gr) 109 200 234 383 71 770 Matrix Free Space (rom) 2.54 2.54 2.54 2.54 2.54 2.54 Fusing Temperature (° C) 260 243 216 216 220.5 248 - - Blowing Ratio 2.6 2.6 2.6 2.6 2.6 4.4 Head Pressure (kg / cm2) 161.7 130.1 154.7 140.6 140.6 144.1 Amperage 14.8 14.0 14.8 14.0 14.5 15.0 Regimen of Ü Matrix 15 Kg / sec / cm) 418.3 463.3 456.9 392.5 444 456.9 A = 370p-335 13.90 8.33 7.59 6.10 10.78 7.5 B = RSI * MI? 0.6 2.68 3.97 3.92 4.33 3.44 4.22 Turbidity < Yes Yes Yes Yes Yes Yes; 30 2.5 < B 6.5 Yes Yes Yes Yes Yes Yes 2 < PDI < 4 Yes Yes Yes Yes Yes Yes 35 1 < CCLDI < 9 Yes Yes Yes Yes Yes Yes 40 Four. Five - - TABLE Example 19 A B C D E Affinity Affinity Exceed Exceed Exceed 1570 1840 399L60 350B60 350D60 MI 0.82 1.10 0.99 0.70 0.96 0.97 Density, (gr / cc) 0.920 0.915 0.910 0.925 0.917 0.917 PDI 3.35 2.26 2.11 2.47 2.34 2.45 Lw / Ln 1.95 1.90 - - 4.78 4.48 RSI 6.94 7.4 8.2 2.4 2.4 2.2 Turbidity () 3.6 7.9 5.6 10.6 8.3 9.3 Extract. of Hexano 1.8 0.5 0.7 0.7 0.3 0.4 Fall of Arrow (gram) 275 413 362 157 613 710 Matrix Free Space (mm) 2.54 2.54 254 2.54 2.54 2.54 Fusing Temperature (° C) 237 209 200 223.9 222.2 222.2 - - Blowing Ratio 2.6 2.6 2.6 2.6 2.6 2.6 Head Pressure (kg / cm.2) 116 98.4 158.2 141 152.6 141 10 Amperage 13.5 11.6 13.9 14.9 14.9 14.9 t- 15 Matrix Regime (Kg / sec / cm) 405.4 440 431.1 437.6 440 437.6 A = 37Op- 335 7.40 5.73 3.87 9.44 6.47 6.47 B = RSI * MI? 0.6 5.66 7.84 8.16 1.93 2.34 2.16 Turbidity < A Yes No No No No No 2.5 < B < 6.5 Yes No No No No No 40 2 < PDI < 4 Yes Yes Yes Yes Yes Yes 1 < CCLDI < 9 Yes Yes - - Yes Yes Four. Five - - TABLE Example F G H I J K Exceed Exc: eed Exact BASF 350L65 357C80 2010 KR1922 HS7093 MI 1.08 3.45 1.55 1.10 0.73 1.97 Density, (gr / cc) 0.917 0.917 0.925 0.909 0.923 0.927 PDI 2.50 2.24 2.03 1.98 2.16 4.10 Lw / Ln 2.80 2.66 1.22 1.89 3.01 13.97 RSI 2.1 1.5 1.8 2.22 2.8 2.8 Turbidity (%) 14.4 20.7 6.5 1.3 6.7 15.6 Extract. of Hexano 0.6 1.0 0.3 0.9 0.5 2.2 Fall of Arrow (gr) 770 368 137 410 158 59 Matrix Free Space (mm) 2.54 2.54 2.54 2.54 2.54 2.54 Fusing Temperature (° C) 223 196 221 221 254 198 Blowing Ratio 2.6 2.6 2.6 2.6 2.6 2.6 Head Pressure (kg / cm2) 134.3 96.7 114.2 130.1 182.8 112.5 Amperage 15.7 13.2 14.7 11.8 15.5 13.0 Regime of 15 Matrix (Kg / sec / c) 424.7 476.2 444 424.7 424.7 456.9 A = 370p-335 6.47 6.47 9.44 3.50 8.70 10.04 B = RSI * MI? 25 0.6 2.20 3.20 2.35 2.3 2.31 4.23 Turbidity < A No No Yes Yes Yes No 2. 5 < B < 6.5 No Yes No No No Yes 35 2 < PDI < 4 Yes Yes Yes No Yes No 1 < CCLDi < 9 Yes Yes Yes Yes Yes No 40 45 TABLE Example L M N O HS7037 HS7028 DFDA 9064 MI 0.52 1.00 1.02 0.90 Density, (gr / cc) 0.923 0.920 0.911 0.916 PDI - - 3.70 2.83 Lw / Ln - - 11.64 2.49 RSI - 4.8 5.6 8.90 Tubidity (%) 10.5 13.5 5.7 - Extract. of Hexano 1.0 3.5 5.9 Fall of Arrow (grams) 50 101 112 Matrix Free Space (mm) 2.54 2.54 2.54 Fusing Temperature (° C) 251.1 215.6 201.70 Blowing Ratio 2.6 2.6 2.6 Head Pressure (kg / cm2) 154.7 147.6 145.9 Amperage 14.5 13.5 14.4 Matrix Regime (Kg / sec / cm) 444 469.8 456.9 A = 370p -335 8.74 7.51 4.39 6.10 B = RSI * MI? 0.6 4.79 5.65 8.31 Turbidity < A No No No - 2.5 < B < 6.5 - Yes Yes No 2 < PDI < 4 - - Yes Yes 1 < CCLDI < 9 - - No Yes

Claims (7)

CLAIMS;

1. An ethylene polymer having: a) a Polydispersity index of from about 2 to about 4; b) a melt index, MI, and a Relaxation Spectrum Index, RSI, such as (RSI) (MIÓ.6) which is from about 2.5 to about 6.5; c) a Cw / Ln Crystallizable Chain Length Distribution index, from about 1 to about 9; and d) a density, p, and a percentage of turbidity when manufactured in a film such that the haze percentage is less than 370p-330.

2. The ethylene polymer according to claim 1, which contains about 1 to about 40 weight percent of a linear or branched alpha-olefin having from 3 to about 20 carbon atoms.

3. The ethylene polymer according to claim 1, which contains from about 1 percent to about 40 weight percent of a comonomer that is selected from propylene, 1-butene, 1-hexene, 4-methyl-l- pentene, 1-octene and mixtures thereof.

4. A film, extrusion coating, insulation for wire and cable and / or sleeves, crosslinked energy cable insulation, molded articles, or insulation jackets and / or semiconductor sleeves and / or shields comprising the ethylene polymer in accordance with claim 1.

5. An ethylene polymer prepared by contacting ethylene and optionally a higher alpha-olefin under polymerization conditions with a catalyst composition in unsupported liquid form, the catalyst composition comprising a transition metal catalyst which essentially does not produces long chain branching.

6. The ethylene polymer according to claim 5, wherein the transition metal catalyst is indenyl zirconium tris (diethylcarbamate) or indenyl zirconium tris (pivalate).

7. The ethylene polymer according to claim 5, prepared by the gas phase polymerization.