KR20070119645A - Compositions of ethylene/alpha-olefin multi-block interpolymer for blown films with high hot tack - Google Patents

Abstract

The present invention relates to film layers and compositions having improved hot tack properties. The compositions comprise at least one ethylene/alpha-olefin interpolymer, wherein the ethylene/alpha-olefin interpolymer may have, for example, a Mw/Mn from about 1.7 to about 3.5, at least one melting point, Tm, in degrees Celsius, and a density, d, in grams/cubic centimeter, wherein the numerical values of Tm and d correspond to the relationship: Tm >-2002.9 + 4538.5(d)-2422.2(d)2.

Description

Ethylene / α-olefin multiblock interpolymer composition for blown films with high temperature tackiness {COMPOSITIONS OF ETHYLENE / α-OLEFIN MULTI-BLOCK INTERPOLYMER FOR BLOWN FILMS WITH HIGH HOT TACK}

The present invention relates to ethylene / α-olefin multiblock interpolymer compositions having hot tack properties and films made therefrom.

It is often desirable to coat an article, substrate, or film to modify properties. Particularly preferred coatings are heat-sealable films, ie films which can be bonded to the film itself, another film or another substrate by applying heat and / or pressure. In this way, the article, substrate or film can be sealed to form a structure such as a bag or other packaging material.

Laminates and monolayer or multilayer films are often two packaging materials using heat-sealable layers. Laminates are conveniently prepared by coating a substrate, such as paper or film, into a heat-sealable layer by extrusion coating. Extrusion coating is a method wherein a polymer or blend of polymers is fed into an extruder hopper. In the hopper, the polymer or blend melts and passes through a die to form a web. The web is then extruded onto the substrate via a nip roll / chill roll interface, for example so that the molten web is pressed onto the substrate. The substrate is cooled by a chill roll and rolled up in a winder.

Similarly, many other methods are often used to make monolayer or multilayer films useful as packaging materials. Such methods may include tenter frame techniques as well as bubble extrusion and biaxial orientation methods. To facilitate sealing, heat-sealable films are generally used alone or in the case of multilayer films as the outermost layer or the innermost layer.

Laminates with a heat-sealable film layer and monolayer or multilayer films are often used in "molding, filling and sealing" machines. These instruments produce a continuous stream of packaging that can be closed by film-to-film sealing from the film. Often such packaging is sealed through heat and pressured heat seal jaws to form a seal closure between the film and the film.

Heat seal closures made through heat seal baths will often be the strongest after the seal has cooled to ambient temperature. However, to increase the production capacity, the packaging material is often filled with the product before the lower seal is completely cooled, so that the polymer at the sealing interface is not completely solidified (or recrystallized) or is still softened. Thus, the closure must exhibit sufficient strength very quickly without the need to cool to ambient temperature. Otherwise, the closure will be broken by the weight of the product when the packaging material is filled.

"Seal strength" is the strength of a heat seal at ambient temperature after a seal has been formed and its full strength has been reached. However, as described above, the sealing properties at temperatures after forming and before cooling to ambient conditions are often important. The nature of the seal strength above ambient temperature is often referred to as the "hot tack" property.

There are many different high temperature tack properties that are important for heat-sealable films. One important high temperature tack property is "starting temperature". The onset temperature is the first temperature above the ambient temperature at which a seal can be formed by applying a given pressure to a film of a given thickness for a given time. Often, the onset temperature is expressed as the minimum temperature at which a 2 mil film forms a seal having a strength of 0.5 N / in. Using ASTM F 1921, Method B. In general, lower onset temperatures are preferred because they require less energy used to form the seal, and also because the time taken to form the initial seal at a given seal bath temperature is shorter. Thus, the production speed can be increased.

Another important high temperature tack property is "extreme high temperature tack". Extreme high temperature tack is the maximum strength the seal has at temperatures above the onset temperature. In general, extreme high temperature tack is desirable to occur at the lowest possible temperature. Another generally preferred high temperature tack property is a wide processing window that allows the film to exhibit suitable sealing strength when measured over a wide temperature range. In addition, generally, it is a high temperature high temperature tack so that the sealing strength is sufficiently maintained even at an elevated temperature.

High temperature tack properties are often determined by the composition used to form the film seal. Conventionally, compositions have been used that are mixtures of, for example, low density polyethylene and linear low density ethylene hydrocarbon copolymers, such as those described in US Pat. No. 4,339,507 and US Pat. No. 5,741,861. Unfortunately, however, such compositions often have high temperature tack properties that can limit production capacity. The composition of US Pat. No. 6,262,174, for example comprising a mixture of polypropylene and polyethylene, solves many of the problems mentioned above. However, there is still a need to find new compositions with improved high temperature tack properties and wide melting temperature windows. In addition, for applications where each of the openings is required (eg, grain box), compositions having a controlled heat seal strength are preferred.

Advantageously, new compositions have been found that provide excellent high temperature tack properties, wide processing windows and controlled heat seal strength. The composition comprises at least one ethylene / α-olefin interpolymer. The composition may further comprise one or more other polymers as well as one or more additives. Suitable film structures include both monolayer and multilayer films.

FIG. 1 shows the melting point / density relationship of the polymer of the present invention (indicated by diamond) compared to conventional random copolymers (indicated by circles) and Ziegler-Natta copolymers (indicated by triangles).

2 shows a plot of delta DSC-CRYSTAF as a function of DSC melt enthalpy for various polymers. Diamonds are random ethylene / octene copolymers; Squares are polymers Examples 1-4; Triangles are polymers Examples 5-9; Circles represent Polymer Examples 10-19. The symbol "X" represents Polymer Examples A ^* to F ^* .

FIG. 3 shows elasticity for non-oriented films made from the inventive interpolymers (represented by squares and circles) and conventional copolymers (various Dow AFFINITY® polymers, represented by triangles). The effect of density on the recovery rate is shown. Squares represent ethylene / butene copolymers of the present invention, and circles represent ethylene / octene copolymers of the present invention.

FIG. 4 shows the octene content of TREF fractionated ethylene / 1-octene copolymer fraction versus TREF elution temperature of the polymer fraction of Example 5 (indicated by circles) and the comparative polymers E and F fractions (indicated by symbol “X”). Is a plot of. Diamonds represent conventional random ethylene / octene copolymers.

5 is a plot of the octene content of the TREF fractionated ethylene / 1-octene copolymer fraction versus the TREF elution temperature of the polymer fraction of Example 5 (curve 1) and the polymer fraction of Comparative Example F (curve 2). Squares represent Example F ^* and triangles represent Example 5.

FIG. 6 shows two ethylenes of the invention prepared using comparative ethylene / 1-octene copolymer (curve 2) and propylene / ethylene copolymer (curve 3) and different amounts of chain shuttling agent. It is a graph of log storage modulus as a function of temperature for / 1-octene block copolymer (curve 1).

FIG. 7 shows a plot of TMA (1 mm) versus flexural modulus for some polymers of the invention (represented by diamond) compared to some known polymers. Triangles represent various Dow VERSIFY® polymers, circles represent various random ethylene / styrene copolymers, and squares represent various Dow Affinity® polymers.

General definition

"Polymer" means a polymeric compound prepared by polymerizing monomers of the same or different types. The general term "polymer" encompasses the terms "homopolymer", "copolymer", "terpolymer" and "interpolymer".

"Interpolymer" means a polymer prepared by polymerizing two or more different types of monomers. The general term "interpolymer" refers to the term "copolymer" (commonly used to refer to a polymer made from two different monomers) and the term "terpolymer" (a polymer made from three different types of monomers) Commonly used). Interpolymers also encompass polymers made by polymerizing four or more monomers.

The term “ethylene / α-olefin interpolymer” generally refers to a polymer comprising ethylene and an α-olefin having at least 3 carbon atoms. Preferably, ethylene comprises most of the mole fraction of the total polymer, ie ethylene comprises at least about 50 mol% of the total polymer. More preferably, ethylene comprises at least about 60 mol%, at least about 70 mol%, or at least about 80 mol%, with the substantial remainder of the entire polymer being preferably an α-olefin having 3 or more carbon atoms. At least one other comonomer. For many ethylene / octene copolymers, preferred compositions have an ethylene content of greater than about 80 mol% of the total polymer and an octene content of about 10 to about 15 mol%, preferably about 15 to about 20 mol% of the total polymer. Include. In some embodiments, the ethylene / α-olefin interpolymers do not include those produced in low yield or in small amounts or as a byproduct of a chemical process. The ethylene / α-olefin interpolymers may be blended with one or more polymers, but the resulting ethylene / α-olefin interpolymers are substantially pure and are often included as a major component of the reaction product of the polymerization process.

Ethylene / α-olefin interpolymers comprise ethylene and one or more copolymerizable α-olefin comonomers in polymerized form and feature multiple blocks or segments having two or more polymerized monomer units that differ in chemical or physical properties. It is done. In other words, the ethylene / α-olefin interpolymers are block interpolymers, preferably multiblock interpolymers or copolymers. The terms "interpolymer" and "copolymer" are used interchangeably herein. In some embodiments, the multiblock copolymer can be represented by the formula:

(AB) _n

Wherein n is an integer greater than or equal to 1, preferably greater than 1, such as 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100 or more "A" represents a hard block or segment and "B" represents a soft block or segment. Preferably, A and B are connected in a substantially linear manner rather than in a substantially branched or substantially star form. In other embodiments, A blocks and B blocks are randomly distributed along the polymer chain. That is, the block copolymer typically does not have a structure such as AAA-AA-BBB-BB.

In other embodiments, the block copolymers typically do not have a third type of block comprising different comonomer (s). In another embodiment, block A and block B each have monomers or comonomers distributed substantially randomly within the block. That is, block A and block B both do not include two or more sub-segments (or sub-blocks) with different compositions, such as tip segments having compositions substantially different from the rest of the block.

Multiblock polymers typically include varying amounts of "hard" and "soft" segments. A “hard” segment refers to a block of polymerized units in which ethylene is present in an amount greater than about 95 weight percent, preferably greater than about 98 weight percent, based on the weight of the polymer. That is, the comonomer content (content of monomers other than ethylene) in the hard segments is less than about 5 weight percent, preferably less than about 2 weight percent based on the weight of the polymer. In some embodiments, the hard segments are all or substantially all composed of ethylene. In contrast, a "soft" segment has a comonomer content (content of monomers other than ethylene) of greater than about 5 weight percent, preferably greater than about 8 weight percent, greater than about 10 weight percent, or about 15 weight based on the weight of the polymer. A block of polymerized units that are greater than% is shown. In some embodiments, the comonomer content in the soft segment is greater than about 20 weight percent, greater than about 25 weight percent, greater than about 30 weight percent, greater than about 35 weight percent, greater than about 40 weight percent, greater than about 45 weight percent, about 50 Greater than about 60 weight percent or greater than about 60 weight percent.

Soft segments are often from about 1% to about 99% by weight, preferably from about 5% to about 95%, from about 10% to about 90% by weight, based on the total weight of the block copolymer in the block copolymer, About 15 wt% to about 85 wt%, about 20 wt% to about 80 wt%, about 25 wt% to about 75 wt%, about 30 wt% to about 70 wt%, about 35 wt% to about 65 wt%, About 40% to about 60%, or about 45% to about 55% by weight. In contrast, hard segments may exist in a similar range. Soft segment weight percent and hard segment weight percent may be calculated based on data obtained from DSC or NMR. Such methods and calculations are described in the context of Choline L.P. At the same time, filed March 15, 2006 under the names Colin LP Shan, Lonnie Hazlitt, and assigned to Dow Global Technologies Inc. US Patent Application ____ of Olefin Block Interpolymers (inserted when published): Attorney's Case No. 385063-999558.

The term "crystalline", when used, refers to a polymer having a primary transition temperature or crystal melting point (Tm), measured by differential scanning calorimetry (DSC) or equivalent technique. This term may be used interchangeably with the term "semicrystalline". The term “amorphous” refers to a polymer having no crystalline melting point measured by differential scanning calorimetry (DSC) or equivalent technique.

The term "multiblock copolymer" or "segmented copolymer" preferably refers to polymers comprising two or more chemically distinct regions or segments connected in a linear manner, ie polymerized ethylene functional groups rather than pendant or grafted It refers to a polymer comprising end to end linked chemically differentiated units. In a preferred embodiment, the block comprises the amount or type of comonomer incorporated therein, the density, the amount of crystallization, the microcrystalline size attributable to the polymer of this composition, the type or degree of tacticity (isotactic or syn Different amounts, homogeneity, or any other chemical or physical property of branching, including diotactic), regio-regular or site-irregularity, long chain branching or hyper-branching. Multiblock copolymers are characterized by the distribution of specific polydispersity indices (PDI or M _w / M _n ), block length distribution and / or block number distribution due to specific copolymer preparation methods. More specifically, when produced in a continuous process, the polymer preferably has a PDI of 1.7 to 2.9, preferably 1.8 to 2.5, more preferably 1.8 to 2.2 and most preferably 1.8 to 2.1. When produced in a batch or semi-batch process, the polymer has a PDI of 1.0 to 2.9, preferably 1.3 to 2.5, more preferably 1.4 to 2.0 and most preferably 1.4 to 1.8.

In the following description, all values disclosed herein are approximations whether or not the term "about" or "approximately" is used in this regard. They may vary by 1%, 2%, 5%, or sometimes 10-20%. When a numerical range having a lower limit (R ^L ) and an upper limit (R ^U ) is disclosed, any numerical value included in the range is specifically disclosed. Specifically, the following numerical values within the range are specifically disclosed: R = R ^L + k * (R ^U -R ^L ) where k is a variable ranging from 1% to 100% in 1% increments, ie k Is 1%, 2%, 3%, 4%, 5%, ..., 50%, 51%, 52%, ..., 95%, 96%, 97%, 98%, 99% or 100% being). In addition, any numerical range defined by two R values as defined above is also specifically disclosed.

Ethylene / α-olefin Interpolymers

The ethylene / α-olefin interpolymers (also referred to as “interpolymers of the invention” or “polymers of the invention”) used in embodiments of the present invention are those of two or more polymerized monomer units that differ in chemical or physical properties. Ethylene and at least one copolymerizable α-olefin comonomer, characterized by multiblock or segment (block interpolymers), preferably multiblock copolymers, are included in polymerized form. Ethylene / α-olefin interpolymers are characterized by one or more of the aspects described below.

In one aspect, the ethylene / α-olefin interpolymers used in embodiments of the present invention have an M _w / M _n of about 1.7 to about 3.5, and at least one melting point (T _m ) (degrees C) and density (d) ( g / cm ³ ), and the values of these variables correspond to the following relations.

T _m > -2002.9 + 4538.5 (d)-2422.2 (d) ² ,

Preferably T _m ≧ −6288.1 + 13141 (d) -6720.3 (d) ² ,

More preferably T _m ≥ 858.91-1825.3 (d) + 1112.8 (d) ² .

This melting point / density relationship is shown in FIG. 1. Unlike typical random copolymers of ethylene / α-olefins, which have a lower melting point with decreasing density, the interpolymers of the present invention (denoted as diamonds), especially when the density is from about 0.87 g / cc to about 0.95 g / cc It shows a melting point that is substantially independent of density. For example, the melting point of such polymers ranges from about 110 ° C. to about 130 ° C. when the density is between 0.875 g / cc and about 0.945 g / cc. In some embodiments, the melting point of such polymers range from about 115 ° C. to about 125 ° C. when the density ranges from 0.875 g / cc to about 0.945 g / cc.

In another aspect, the ethylene / α-olefin interpolymers comprise ethylene and one or more α-olefins in polymerized form, wherein the temperature of the maximum differential scanning calorimetry (“DSC”) peak—the highest crystallization analysis fractionation (“CRYSTAF Is characterized by a delta amount ΔT (degrees Celsius), and heat of fusion ΔH (J / g), defined as the temperature of the peak, and ΔT and ΔH for the ΔH of 130 J / g or less. The same relation is satisfied.

ΔT> -0.1299 (ΔH) + 62.81,

Preferably ΔT ≧ −0.1299 (ΔH) +64.38,

More preferably ΔT ≧ −0.1299 (ΔH) +65.95.

In addition, when (DELTA) H exceeds 130 J / g, (DELTA) T is 48 degreeC or more. CRYSTAF peaks are measured using at least 5% of the cumulative polymer (ie, peaks must represent at least 5% of the cumulative polymer), and if less than 5% of the polymers have an identifiable CRYSTAF peak, the CRYSTAF temperature is 30 ° C. And ΔH are numerical values of heat of fusion (J / g). More preferably, the highest CRYSTAF peak contains at least 10% of the cumulative polymer. 2 shows the data plotted for the polymers of the invention as well as the comparative examples. The integral peak area and peak temperature are calculated with a computerized drawing program provided by the instrument manufacturer. The diagonal line shown for the random ethylene octene comparison polymer corresponds to the equation ΔT = −0.1299 (ΔH) +62.81.

In another aspect, the ethylene / α-olefin interpolymers have molecular fractions that elute at 40 ° C. to 130 ° C. when fractionated using temperature eluting fractionation (“TREF”), which fractions elute at the same temperature range. Characterized by having a comonomer molar content higher than the comonomer molar content of the comparative random ethylene interpolymer fraction, preferably at least 5% higher, more preferably at least 10% higher, wherein the comparative random ethylene interpolymer Has the same comonomer (s) as the blocked interpolymer and has a melt index, density and comonomer molar content (based on total polymer) within 10% of the block interpolymer. Preferably, M _w / M _n of the comparative interpolymer is also within 10% of M _w / M _n of the block interpolymer, and / or the total comonomer content of the comparative interpolymer is 10 weights for the block interpolymer. It is within%.

In another aspect, the ethylene / α-olefin interpolymers are characterized by 300% strain and elastic recovery in one cycle (Re) (%) as measured on compression molded films of ethylene / α-olefin interpolymers, Having a density (d) (g / cm ³ ), wherein the values of Re and d satisfy the following relationship when the ethylene / α-olefin interpolymers do not substantially comprise a crosslinked phase.

Re> 1481-1629 (d);

Preferably Re ≧ 1491-1629 (d);

More preferably Re ≧ 1501-1629 (d);

Even more preferably Re ≧ 1511-1629 (d).

3 shows the effect of density on elastic recovery for non-oriented films made from certain interpolymers and conventional random copolymers of the present invention. At the same density, the inventive interpolymers have substantially higher elastic recovery.

In some embodiments, the ethylene / α-olefin interpolymer has a tensile strength of greater than 10 MPa, preferably of at least 11 MPa, more preferably of at least 13 MPa, and / or of 11 cm / min crosshead It has a breaking elongation of at least 600%, more preferably at least 700%, very preferably at least 800% and most very preferably at least 900% at the separation rate.

In another embodiment, the ethylene / α-olefin interpolymer has (1) a storage modulus ratio G ′ (25 ° C.) / G ′ (100 ° C.) of 1 to 50, preferably 1 to 20, more preferably 1 To 10 and / or; (2) 70 ° C. Compression set is less than 80%, preferably less than 70%, in particular less than 60%, less than 50%, or less than 40% and up to 0%.

In another embodiment, the ethylene / α-olefin interpolymer has a 70 ° C. compression set of less than 80%, less than 70%, less than 60%, or less than 50%. Preferably, the 70 ° C. compression set of the interpolymer is less than 40%, less than 30%, less than 20% and can be reduced to about 0%.

In some embodiments, the ethylene / α-olefin interpolymer has a heat of fusion less than 85 J / g, and / or 100 lb / ft ² (4800 Pa) or less, preferably 50 lb / ft ² (2400 Pa) or less , In particular, has a pellet blocking strength of less than 5 lb / ft ² (240 Pa) and also as low as 0 lb / ft ² (0 Pa).

In other embodiments, the ethylene / α-olefin interpolymers comprise at least 50 mol% ethylene in polymerized form and have a 70 ° C. compression set of less than 80%, preferably less than 70%, or less than 60%, most Preferably it is less than 40-50% and decreases to near 0%.

In some embodiments, the multiblock copolymer has a PDI that fits the Schultz-Flory distribution rather than the Poisson distribution. The copolymer has both a polydisperse block distribution and a polydisperse block size distribution, and is also characterized by having the most possible block length distribution. Preferred multiblock copolymers are copolymers containing four or more blocks or segments, including terminal blocks. More preferably, the copolymer comprises 5, 10 or 20 or more blocks or segments, including end blocks.

Comonomer content can be measured using any suitable technique, with techniques based on nuclear magnetic resonance ("NMR") spectroscopy preferred. In addition, in the case of polymers or blends of polymers having a relatively wide TREF curve, preferably the TREF is first used to fractionate the polymers into fractions each having an elution temperature range of 10 ° C. or less. That is, each eluted fraction has a collection temperature window of 10 ° C. or less. Using this technique, the block interpolymers have one or more fractions having a higher comonomer molar content than the corresponding fractions of the comparative interpolymers.

In another aspect, the polymer of the present invention preferably comprises a plurality of blocks comprising two or more polymerized monomer units, preferably comprising polymerized forms of ethylene and one or more copolymerizable comonomers and having different chemical or physical properties ( That is, olefin interpolymers (blocked interpolymers) characterized by two or more blocks) or segments, most preferably multiblock copolymers, which block elution (individual fractions) which elute at 40 ° C. to 130 ° C. Collected and / or not isolated) peaks (not molecular fractions only), which peaks have a comonomer content predicted by infrared spectroscopy at development using a full width at half maximum (FWHM) area calculation, and a full width at half maximum (FWHM) ) Higher than the average comonomer molar content of the comparative random ethylene interpolymer peak at the same elution temperature developed using area calculation. Preferably at least 5% higher, more preferably at least 10% higher average comonomer molar content, wherein the comparative random ethylene interpolymer has the same comonomer (s) as the blocked interpolymer It has a melt index, density and comonomer molar content (based on total polymer) within 10% by weight of the block interpolymer. Preferably, M _w / M _n of the comparative interpolymer is also within 10% of M _w / M _n of the blocked interpolymer, and / or the total comonomer content of the comparative interpolymer is 10 in the case of block interpolymers. It is within%. The full width at half maximum (FWHM) calculation is based on the ratio of methyl to methylene reaction area [CH ₃ / CH ₂ ] from the ATREF infrared detector, where the highest (maximum) peak is identified from the baseline and thus the FWHM area is determined. In the distribution measured using the ATREF peak, the FWHM area is defined as the area under the curve between T ₁ and T ₂ , where T ₁ and T ₂ are horizontal lines to the baseline after dividing the ATREF peak height by 2 (ATREF Traversing the left and right sides of the curve) to determine the left and right sides of the ATREF peak. A calibration curve for comonomer content is obtained by plotting the FWHM area ratio of comonomer content from NMR to TREF peak using a random ethylene / α-olefin copolymer. In this infrared method, a calibration curve is obtained for the same comonomer type of interest. The comonomer content of the TREF peak of the polymers of the present invention can be measured with reference to such calibration curves using the FWHM methyl: methylene area ratio [CH ₃ / CH ₂ ] of its TREF peak.

Comonomer content can be measured using any suitable technique, with techniques based on nuclear magnetic resonance (NMR) spectroscopy preferred. Using this technique, the blocked interpolymers have a higher comonomer molar content than the corresponding comparative interpolymers.

Preferably, in the interpolymers of ethylene and 1-octene, the block interpolymers have a comonomer content of the TREF fraction eluting at 40 ° C. to 130 ° C. of at least (-0.2013) T + 20.07, more preferably (- Greater than or equal to 0.2013) T + 21.07 (where T is the value of the peak elution temperature of the compared TREF fraction, measured in ° C.).

FIG. 4 graphically illustrates embodiments of block interpolymers of ethylene and 1-octene and plots of comonomer content versus TREF elution temperature for various comparative ethylene / 1-octene interpolymers (random copolymers). (-0.2013) fitted to the line (solid line) representing T + 20.07. The line of Equation (-0.2013) T + 21.07 is shown as a dotted line. Also shown is the comonomer content for the fractions of the ethylene / 1-octene multiblock interpolymers (multiblock copolymers) of the present invention. All block interpolymer fractions had significantly higher 1-octene content compared to the line at equivalent elution temperatures. These results are characteristic of the interpolymers of the present invention, which are believed to be due to the presence of differentiated blocks in the polymer chain having both crystalline and amorphous properties.

FIG. 5 graphically illustrates the TREF curve and comonomer content for the polymer fractions of Example 5 and Comparative Example F, discussed below. The peaks eluting at 40 ° C. to 130 ° C., preferably 60 ° C. to 95 ° C., for the two polymers were separated into three portions, each eluting for a temperature range below 10 ° C., respectively. Actual data for Example 5 are shown as triangles. One skilled in the art can construct appropriate calibration curves for interpolymers containing different comonomers, and random copolymers prepared using comparative interpolymers, preferably metallocenes or other homogeneous catalyst compositions, having the same monomers It can be appreciated that a line matching the TREF value obtained from can be used for comparison. The interpolymers of the present invention are characterized by a comonomer molar content that is greater than, preferably at least 5% and more preferably at least 10% greater than the value measured from the calibration curve at the same TREF elution temperature.

In addition to the foregoing aspects and properties described herein, the polymers of the present invention may be characterized as having one or more additional features. In one aspect, the polymer of the invention preferably comprises a plurality of blocks or segments comprising two or more polymerized monomer units, preferably in polymerized form, comprising ethylene and one or more copolymerizable comonomers in different chemical or physical properties. Olefin interpolymers (blocked interpolymers), most preferably multiblock copolymers, characterized in that the block interpolymers have molecular fractions that elute at 40 ° C. to 130 ° C. when fractionated using TREF increments. Is a comonomer mole higher than the comonomer mole content of the comparative random ethylene interpolymer fraction eluting in the same temperature range, preferably at least 5% higher, more preferably at least 10%, 15%, 20% or 25% higher. Content, wherein the comparative random ethylene interpolymer is the same as the blocked interpolymer Has a comonomer (s), preferably it has the same comonomer (s), and a mixed blocked less than 10% the melt index, density, and molar comonomer content of the polymer (based on total polymer). Preferably, in the case of a copolymer in which M _w / M _n of the comparative interpolymer is also within 10% of M _w / M _n of the blocked interpolymer, and / or the total comonomer content of the comparative interpolymer is blocked It is within 10 weight%.

Preferably, the interpolymer has, in particular, a total polymer density of from about 0.855 to about 0.935 g / cm ³ , more particularly the polymer has more than about 1 mol% comonomer, and the blocked interpolymer is from 40 ° C. to The comonomer content of the TREF fraction eluted at 130 ° C. is greater than or equal to (-0.1356) T + 13.89, more preferably greater than or equal to (−0.1356) T + 14.93, most preferably greater than or equal to (-0.2013) T + 21.07. A quantity of at least an interpolymer of ethylene and at least one α-olefin, where T is the value of the peak ATREF elution temperature of the compared TREF fraction, measured in degrees Celsius.

Preferably, in the case of said interpolymers of ethylene and at least one α-olefin, in particular interpolymers having a total polymer density of from about 0.855 to about 0.935 g / cm ³ , more particularly more than about 1 mol% of polymer In the case of polymers with monomers, the blocked interpolymers have a comonomer content of the TREF fraction eluting at 40 ° C. to 130 ° C. of at least an amount of (-0.2013) T + 20.07, more preferably of (-0.2013) T + 21.07. More than (where T is the value of the peak elution temperature of the compared TREF fraction, measured in ° C.).

In another aspect, the polymer of the invention preferably comprises a plurality of blocks comprising two or more polymerized monomer units, preferably in polymerized form, comprising ethylene and one or more copolymerizable comonomers in different chemical or physical properties, or Olefin interpolymers (blocked interpolymers) characterized by segments, most preferably multiblock copolymers, said block interpolymers having molecular fractions which elute at 40 ° C. to 130 ° C. when fractionated using TREF increments, All fractions having a comonomer content of at least about 6 mol% have a melting point above about 100 ° C. For fractions having a comonomer content of about 3 mol% to about 6 mol%, all fractions have a DSC melting point of about 110 ° C. or greater. More preferably, the polymer fraction having at least 1 mol% comonomer has a DSC melting point corresponding to the following formula.

Tm ≥ (-5.5926) (mol% of comonomer in the fraction) + 135.90

In another aspect, the polymer of the invention preferably comprises a plurality of blocks comprising two or more polymerized monomer units, preferably in polymerized form, comprising ethylene and one or more copolymerizable comonomers in different chemical or physical properties, or Olefin interpolymers (blocked interpolymers) characterized by segments, most preferably multiblock copolymers, said block interpolymers having molecular fractions which elute at 40 ° C. to 130 ° C. when fractionated using TREF increments, All fractions having an ATREF elution temperature above about 76 ° C. are characterized by having a melting enthalpy (heat of fusion) corresponding to the following equation as determined by DSC.

Heat of fusion (J / g) ≤ (3.1718) (ATREF elution temperature (Celsius))-136.58

The block interpolymers of the present invention have molecular fractions that elute at 40 ° C. to 130 ° C. when fractionated using TREF increments, and all fractions having ATREF elution temperatures of 40 ° C. to less than about 76 ° C. It is characterized by having a melting enthalpy (heat of fusion) corresponding to the equation.

Heat of fusion (J / g) ≤ (1.1312) (ATREF elution temperature (Celsius)) + 22.97

Measured by an infrared detector ATREF  peak Comonomer  Furtherance

The comonomer composition of the TREF peak can be measured using an IR4 infrared detector available from Polymer Char (Valencia, Spain) ( http://www.polymerchar.com/ ).

The "composition mode" of the detector is equipped with a measuring sensor (CH ₂ ) and a composition sensor (CH ₃ ) (fixed narrow band infrared filter in the region of 2800 to 3000 cm ^-1 ). The measurement sensor detects methylene (CH ₂ ) carbon on the polymer, which is directly related to the polymer concentration in solution, and the composition sensor detects the methyl (CH ₃ ) group of the polymer. The mathematical ratio of the composition signal (CH ₃ ) divided by the measurement signal (CH ₂ ) is sensitive to the comonomer content of the polymer in the measured solution and its response is corrected by known ethylene alpha-olefin copolymer standards.

The detector, when used with an ATREF instrument, provides both the concentration (CH ₂ ) and composition (CH ₃ ) signal response of the polymer eluted during the TREF process. Polymer specific correction can be obtained by measuring the area ratio of CH ₃ to CH ₂ to the polymer by known comonomer content (preferably determined by NMR). The comonomer content of the ATREF peak of the polymer can be predicted by applying a baseline correction of the area ratio for the individual CH ₃ and CH ₂ reactions (ie, area ratio CH ₃ / CH ₂ to comonomer content).

The area of the peak can be calculated using the full width at half maximum (FWHM) calculation after integrating the individual signal responses from the TREF chromatogram using the appropriate baseline. The full width at half maximum is based on the ratio of methyl to methylene reaction area [CH ₃ / CH ₂ ] from the ATREF infrared detector, where the highest (maximum) peak is identified from the baseline and thus the FWHM area is determined. In the distribution measured using the ATREF peak, the FWHM area is defined as the area under the curve between T ₁ and T ₂ , where T ₁ and T ₂ are horizontal lines to the baseline after dividing the ATREF peak height by 2 (ATREF Traversing the left and right sides of the curve) to determine the left and right sides of the ATREF peak.

The application of infrared spectroscopy to determine the comonomer content of polymers in this ATREF-infrared method is in principle similar to that of the GPC / FTIR system as described in the following references: Markovich, Ronald P .; Hazlitt, Lonnie G .; Smith, Linley; "Development of gel-permeation chromatography-Fourier transform infrared spectroscopy for characterization of ethylene-based polyolefin copolymers", Polymeric Materials Science and Engineering (1991), 65, 98-100 .; And Deslauriers, P. J .; Rohlfing, D. C .; Shieh, E. T .; "Quantifying short chain branching microstructures in ethylene-1-olefin copolymers using size exclusion chromatography and Fourier transform infrared spectroscopy (SEC-FTIR)", Polymer (2002), 43, 59-170.] Introduced for reference).

In other embodiments, the ethylene / α-olefin interpolymers of the invention are characterized by an average block index (ABI) of greater than 0 and up to about 1.0, and a molecular weight distribution (M _w / M _n ) of greater than about 1.3. The average block index (ABI) is the weight average of the block index (“BI”) of each polymer fraction obtained in the preparative TREF at 20 ° C. to 110 ° C. in 5 ° C. increments.

Wherein BI _i is the block index for the i-th fraction of the ethylene / α-olefin interpolymers of the invention obtained in the preparative TREF and w _i is the weight percent of the i-th fraction.

For each polymer fraction, BI is defined by one of the following two equations, both of which give the same BI value.

Wherein T _X is the preparative ATREF elution temperature (preferably expressed in Kelvin) for the i-th fraction and P _X is the ethylene mole fraction for the i-th fraction which can be measured by NMR or IR as above. P _AB is the ethylene mole fraction of the total ethylene / α-olefin interpolymer (before fractionation), which can also be measured by NMR or IR. T _A and P _A are the ATREF elution temperature and ethylene mole fraction for pure “hard segments” (referring to the crystalline segments of the interpolymer). If the measured value for the "hard segment" is not valid, the T _A and P _A values as the first approximation are set to the values for the high density polyethylene homopolymer. In the calculations performed herein, T _A is 372 ° K and P _A is 1.

T _AB is the ATREF temperature for random copolymers of the same composition with an ethylene mole fraction of P _AB . T _AB can be calculated from the following equation.

Ln P _AB = α / T _AB + β

Wherein α and β are two constants that can be determined by correction using a number of known random ethylene copolymers. It should be noted that α and β may vary from instrument to instrument. In addition, it is necessary to obtain their calibration curves in the polymer composition of interest and also in the molecular weight range similar to the fractions. There is a slight molecular weight effect. If the calibration curve is obtained from similar molecular weight ranges, this effect is essentially negligible. In some embodiments, the random ethylene copolymer satisfies the following relationship.

Ln P = -237.83 / T _ATREF + 0.639

T _XO is the ATREF temperature for random copolymers of the same composition with an ethylene mole fraction of P _X. T _XO can be calculated from LnP _X = α / T _XO + β. Conversely, P _XO is the ethylene mole fraction for random copolymers of the same composition with an ATREF temperature of T _X , which can be calculated from Ln P _XO = α / T _X + β.

Once the block index (BI) for each preparative TREF fraction is obtained, the weight average block index (ABI) for the entire polymer can be calculated. In some embodiments, ABI is greater than zero but less than about 0.3, or from about 0.1 to about 0.3. In other embodiments, ABI is greater than about 0.3 and up to about 1.0. Preferably, the ABI should range from about 0.4 to about 0.7, about 0.5 to about 0.7, or about 0.6 to about 0.9. In some embodiments, ABI ranges from about 0.3 to about 0.9, about 0.3 to about 0.8, about 0.3 to about 0.7, about 0.3 to about 0.6, about 0.3 to about 0.5, or about 0.3 to about 0.4. In other embodiments, ABI ranges from about 0.4 to about 1.0, about 0.5 to about 1.0, about 0.6 to about 1.0, about 0.7 to about 1.0, about 0.8 to about 1.0, or about 0.9 to about 1.0.

Another feature of the ethylene / α-olefin interpolymers of the present invention is that the ethylene / α-olefin interpolymers of the present invention have at least one polymer having a block index greater than about 0.1 up to about 1.0, which can be obtained by preparative TREF. Fractions, with a molecular weight distribution (M _w / M _n ) greater than about 1.3. In some embodiments, the polymer fraction has a block index greater than about 0.6 and up to about 1.0, greater than about 0.7 and up to about 1.0, greater than about 0.8 and up to about 1.0, or greater than about 0.9 and up to about 1.0. In other embodiments, the polymer fraction has a block index greater than about 0.1 and up to about 1.0, greater than about 0.2 and up to about 1.0, greater than about 0.3 and up to about 1.0, greater than about 0.4 and up to about 1.0, or greater than about 0.4 and up to about 1.0. In another embodiment, the polymer fraction has a block index greater than about 0.1 and up to about 0.5, greater than about 0.2 and up to about 0.5, greater than about 0.3 and up to about 0.5, or greater than about 0.4 and up to about 0.5. In another embodiment, the polymer fraction has a block index greater than about 0.2 and up to about 0.9, greater than about 0.3 and up to about 0.8, greater than about 0.4 and up to about 0.7, or greater than about 0.5 and up to about 0.6.

For the copolymer of ethylene and an α-olefin, the polymer of the present invention is preferably (1) 1.3 or more, more preferably 1.5 or more, 1.7 or more, or 2.0 or more, most preferably 2.6 or more, maximum 5.0 or less, More preferably a PDI of at most 3.5, in particular at most 2.7; (2) heat of fusion of up to 80 J / g; (3) an ethylene content of at least 50% by weight; (4) has a glass transition temperature (Tg) of less than -25 ° C, more preferably less than -30 ° C, and / or (5) one, also a single, T _m .

In addition, the polymers of the present invention have a storage modulus (G ′) at a temperature of 100 ° C. of which log (G ′) is at least 400 kPa, preferably at least 1.0 MPa, alone or in combination with any other properties. Can be. In addition, the polymers of the present invention have a relatively uniform storage modulus as a function of temperature in the range of 0 to 100 ° C. (shown in FIG. 6), which is a property of the block copolymer, which is characterized in that at least one of olefin copolymers, in particular ethylene, for C _{3 -8} aliphatic copolymers of α- olefin is unknown up to now. (In this context, the term "relatively uniform" means that the log G '(Pa) is reduced to less than one digit range at 50 to 100 ° C, preferably 0 to 100 ° C.)

The interpolymers of the present invention may be further characterized by a thermomechanical analysis penetration depth of 1 mm and a flexural modulus of 3 kpsi (20 MPa) to 13 kpsi (90 MPa) at temperatures above 90 ° C. Alternatively, the inventive interpolymers can have a thermomechanical analysis penetration depth of 1 mm and a flexural modulus of at least 3 kpsi (20 MPa) at temperatures of 104 ° C. or higher. They are characterized by having a wear resistance (volume loss) of less than 90 mm ³ . 7 shows the TMA (1 mm) for the flexural modulus of the polymers of the present invention compared to other known polymers. The polymers of the present invention have a significantly better flexibility-heat resistance balance than other polymers.

In addition, the ethylene / α-olefin interpolymers may be used in an amount of 0.01 to 2000 g / 10 minutes, preferably 0.01 to 1000 g / 10 minutes, more preferably 0.01 to 500 g / 10 minutes, especially 0.01 to 100 g / 10 minutes. May have a melt index (I ₂ ). In certain embodiments, the ethylene / α-olefin interpolymer has 0.01 to 10 g / 10 minutes, 0.5 to 50 g / 10 minutes, 1 to 30 g / 10 minutes, 1 to 6 g / 10 minutes, or 0.3 to 10 g Melt index (I ₂ ) of 10 minutes. In certain embodiments, the melt index of the ethylene / α-olefin polymer is 1 g / 10 minutes, 3 g / 10 minutes or 5 g / 10 minutes.

The polymer has a molecular weight (M) of 1,000 g / mol to 5,000,000 g / mol, preferably 1000 g / mol to 1,000,000, more preferably 10,000 g / mol to 500,000 g / mol, in particular 10,000 g / mol to 300,000 g / mol _w ). The density of the polymer of the present invention may be 0.80 to 0.99 g / cm ³ , preferably 0.85 g / cm ³ to 0.97 g / cm ³ for ethylene containing polymers. In certain embodiments, the density of the ethylene / α-olefin polymer is in the range of 0.860 to 0.925 g / cm ³ or 0.867 to 0.910 g / cm ³ .

Methods of making polymers are disclosed in the following patent applications: US Provisional Application No. 60 / 553,906, filed March 17, 2004; 60 / 662,937, filed March 17, 2005; 60 / 662,939, filed March 17, 2005; 60/5662938, filed March 17, 2005; PCT Application No. PCT / US2005 / 008916, filed March 17, 2005; PCT Application No. PCT / US2005 / 008915, filed March 17, 2005; And PCT / US2005 / 008917, filed March 17, 2005, all of which are incorporated herein by reference in their entirety. For example, one such method involves the process of adding ethylene and optionally one or more addition polymerizable monomers other than ethylene under addition polymerization conditions,

(A) a first olefin polymerization catalyst having a high comonomer incorporation index,

(B) a second olefin polymerization catalyst having a comonomer incorporation index of less than 90%, preferably less than 50%, most preferably less than 5% of the comonomer incorporation index of catalyst (A), and

(C) mixtures or reaction products formed by combining chain transfer agents

It comprises contacting with a catalyst composition comprising a.

Representative catalysts and chain transfer agents are as follows.

Catalyst (A1) : [N- (2,6-di (1-methyl), prepared according to the teachings of WO 03/40195, 2003US0204017, USSN 10 / 429,024, and WO 04/24740, filed May 2, 2003. Ethyl) phenyl) amido) (2-isopropylphenyl) (α-naphthalene-2-diyl (6-pyridin-2-diyl) methane)] hafnium dimethyl.

Catalyst (A2) : [N- (2,6-di (1-methyl), prepared according to the teachings of WO 03/40195, 2003US0204017, USSN 10 / 429,024, and WO 04/24740, filed May 2, 2003. Ethyl) phenyl) amido) (2-methylphenyl) (1,2-phenylene- (6-pyridin-2-diyl) methane)] hafnium dimethyl.

Catalyst (A3) : Bis [N, N '"-(2,4,6-tri (methylphenyl) amido) ethylenediamine] hafnium dibenzyl.

Catalyst (A4) : Bis ((2-oxoyl-3- (dibenzo-1H-pyrrol-1-yl) -5- (methyl) phenyl) -2, prepared according to the teachings of US-A-2004 / 0010103 -Phenoxymethyl) cyclohexane-1,2-diyl zirconium (IV) dibenzyl.

Catalyst (B1) : 1,2-bis- (3,5-di-t-butylphenylene) (1- (N- (1-methylethyl) imino) methyl) (2-oxoyl) zirconium dibenzyl .

Catalyst (B2): 1,2-bis- (3,5-di-t-butylphenylene) (1- (N- (2-methylcyclohexyl) -imino) methyl) (2-oxoyl) zirconium Dibenzyl.

Catalyst ( C1 ) : (t-butylamido) dimethyl (3-N-pyrrolyl-1,2,3,3a, 7a-η-inden-1-yl) silanitanium prepared according to the teachings of USP6,268,444 dimethyl.

Catalyst ( C2 ) : (t-butylamido) di (4-methylphenyl) (2-methyl-1,2,3,3a, 7a-η-indene- prepared according to the teachings of US-A-2003 / 004286 1-yl) silanetitanium dimethyl.

Catalyst ( C3 ) : (t-butylamido) di (4-methylphenyl) (2-methyl-1,2,3,3a, 8a-η-s- prepared according to the teachings of US-A-2003 / 004286 Indansen-1-yl) silanetitanium dimethyl.

Catalyst ( D1 ) : Bis (dimethyldisiloxane) (inden-1-yl) zirconium dichloride available from Sigma-Aldrich.

Transfer agent : The transfer agent used was diethylzinc, di (i-butyl) zinc, di (n-hexyl) zinc, triethylaluminum, trioctylaluminum, triethylgallium, i-butylaluminum bis (dimethyl (t-butyl) Siloxane), i-butylaluminum bis (di (trimethylsilyl) amide), n-octylaluminum di (pyridine-2-methoxide), bis (n-octadecyl) i-butylaluminum, i-butylaluminum bis (di (n-pentyl) amide), n-octyl aluminum bis (2,6-di-t-butylphenoxide, n-octyl aluminum di (ethyl (1-naphthyl) amide), ethyl aluminum bis (t-butyldimethyl Siloxide), ethylaluminum di (bis (trimethylsilyl) amide), ethylaluminum bis (2,3,6,7-dibenzo-1-azacycloheptanamide), n-octylaluminum bis (2,3,6 , 7-dibenzo-1-azacycloheptanamide), n-octylaluminum bis (dimethyl (t-butyl) siloxide, ethylzinc (2,6-diphenylphenoxide) and ethylzinc (t-butoxide) It includes.

Preferably, the method includes using a plurality of catalysts that can not be interconversion of block copolymers, especially multi-block copolymer, preferably two or more monomers, more especially ethylene and a C _{3 -20} olefin or cycloolefin, and most specially it takes the form of a continuous solution process for the production of ethylene and C _{4 -20} linear multi-block of the α- olefin copolymer. That is, the catalyst is chemically different. Under continuous solution polymerization conditions, the process is ideally suited for the polymerization of monomer mixtures of high monomer conversion. Under these polymerization conditions, the transfer from the chain transfer agent to the catalyst is favored over the chain growth, so that multiblock copolymers, especially linear multiblock copolymers, are formed with high efficiency.

The interpolymers of the present invention can be differentiated from conventional random copolymers, physical blends of polymers and block copolymers prepared by sequential monomer addition, flow catalysts, anionic or cationic living polymerization techniques. In particular, compared to random copolymers having the same monomer and monomer content at equivalent crystallinity or modulus, the inventive interpolymers have better (higher) heat resistance (measured by melting point), higher TMA penetration temperature, higher hot tension Strength and / or high hot torsional storage modulus (measured by dynamic mechanical analysis). Compared to random copolymers having the same monomers and monomer content, the interpolymers of the invention have lower compression set, lower stress relaxation, higher creep resistance, higher tear strength, higher blocking resistance, especially at elevated temperatures, Faster set-up due to higher crystallization (solidification) temperature, higher recovery rate (especially at elevated temperatures), better wear resistance, higher shrinkage, and better oil and filler tolerance.

The interpolymers of the present invention also exhibit specific crystallization and branching distribution relationships. That is, the interpolymers of the present invention are CRYSTAF as a function of heat of fusion, in particular compared to random copolymers or physical blends of polymers containing the same monomers and monomer concentrations, such as blends of high density polymers and low density copolymers at equivalent overall density and There is a relatively large difference between the highest peak temperatures measured using DSC. This particular feature of the inventive interpolymers is due to the unique comonomer distribution in the blocks in the polymer backbone. In particular, the interpolymers of the present invention may include alternating blocks (including homopolymer blocks) having different comonomer contents. The interpolymers of the present invention may comprise a distribution that is a Schultz-Florie distribution in the number and / or block size of polymer blocks having different densities or comonomer contents. In addition, the inventive interpolymers also have specific peak melting points and crystallization temperatures that are substantially independent of polymer density, modulus, and shape. In a preferred embodiment, the order of the microcrystals of the polymer exhibits characteristic spherulite and lamella, even distinguishable from random or block copolymers, even at PDI values of less than 1.7, or less than 1.5 and also less than 1.3.

In addition, the interpolymers of the present invention can be prepared using techniques that affect the degree or level of blocking. That is, the length and amount of comonomers of each polymer block and segment can be varied by controlling the ratio and type of catalyst and transfer agent as well as the polymerization temperature, and other polymerization parameters. A surprising advantage of this phenomenon is the discovery that as the degree of blocking increases, the optical properties, tear strength and high temperature recovery properties of the resulting polymers improve. In particular, as the average number of blocks in the polymer increases, the haze decreases with increasing transparency, tear strength and high temperature recovery properties. By selecting a combination of a catalyst and a transfer agent having the desired chain transfer capacity (high transfer rate at low chain termination), other forms of polymer termination are effectively suppressed. Thus, the polymerization of ethylene / α-olefin comonomer mixtures according to embodiments of the present invention results in very little β-hydride removal, even when present, and the resulting crystalline blocks have little or no long chain branching and are very or substantially Completely linear.

Polymers with highly crystalline chain ends can optionally be prepared in accordance with embodiments of the present invention. In elastomer applications, reducing the relative amount of polymer terminated by amorphous blocks reduces the effect of intermolecular dilution on crystalline regions. These results can be obtained by selecting chain transfer agents and catalysts having an appropriate reaction with hydrogen or other chain terminators. Specifically, catalysts that produce highly crystalline polymers (such as by the use of hydrogen, for example) in comparison to catalysts that produce polymer segments that are less crystalline (e.g., by large comonomer incorporation, site-error or atactic polymer formation). If more susceptible to chain termination, the highly crystalline polymer segment occupies the terminal portion of the polymer. Not only are the resulting end groups crystalline, but upon termination, a highly crystalline polymer forming catalyst site is available for resumption of polymer formation once again. Thus, the initially formed polymer is another highly crystalline polymer segment. Thus, both ends of the resulting multiblock copolymer are predominantly highly crystalline.

The ethylene / α-olefin interpolymers used in the embodiments of the present invention are preferably interpolymers of ethylene and at least one C ₃ -C ₂₀ α-olefin. Particular preference is given to copolymers of ethylene and C ₃ -C ₂₀ α-olefins. The interpolymers may further comprise C ₄ -C ₁₈ diolefins and / or alkenylbenzenes. Suitable unsaturated comonomers useful for polymerizing with ethylene include, for example, ethylenically unsaturated monomers, conjugated or nonconjugated dienes, polyenes, alkenylbenzenes and the like. Examples of such comonomers are C ₃ -C ₂₀ α-olefins such as propylene, isobutylene, 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene , 1-nonene, 1-decene and the like. Particular preference is given to 1-butene and 1-octene. Other suitable monomers include styrene, halo- or alkyl-substituted styrenes, vinylbenzocyclobutane, 1,4-hexadiene, 1,7-octadiene and naphthenic components (eg cyclopentene, cyclohexene and Cyclooctene).

Although ethylene / α-olefin interpolymers are preferred polymers, other ethylene / olefin polymers may be used. Olefin as used herein refers to a group of unsaturated hydrocarbon-based compounds having at least one carbon-carbon double bond. Depending on the choice of catalyst, any olefin can be used in embodiments of the present invention. Preferably, suitable olefins are C ₃ -C ₂₀ aliphatic and aromatic compounds containing vinylic unsaturated groups, and cyclic compounds such as cyclobutene, cyclopentene, dicyclopentadiene and norbornene (positions 5 and 6) To norbornene substituted with a C ₁ -C ₂₀ hydrocarbyl or cyclohydrocarbyl group). Mixtures of the olefins as well as mixtures of C ₄ -C ₄₀ diolefin compounds with the olefins are included.

Examples of olefin monomers include propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 4,6-dimethyl-1-heptene, 4 Vinylcyclohexene, vinylcyclohexane, norbornadiene, ethylidene norbornene, cyclopentene, cyclohexene, dicyclopentadiene, cyclooctene, C ₄ -C ₄₀ diene (1,3-butadiene, 1,3 -Pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene), other C ₄ -C ₄₀ α- Olefins and the like, but are not limited thereto. In certain embodiments, the α-olefin is propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, or a combination thereof. Any hydrocarbon containing a vinyl group may be used in embodiments of the present invention, but as the molecular weight of the monomers becomes too high, practical problems such as monomer availability, cost, and the ability to conveniently remove unreacted monomers from the resulting polymers are further increased. It can be a problem.

The polymerization process described herein is well suited for the preparation of olefin polymers comprising monovinylidene aromatic monomers including styrene, o-methyl styrene, p-methyl styrene, t-butyl styrene and the like. In particular, interpolymers comprising ethylene and styrene can be prepared according to the teachings herein. Optionally, copolymers comprising optionally C ₄ -C ₂₀ dienes, including ethylene, styrene and C ₃ -C ₂₀ alpha olefins with improved properties can be prepared.

Suitable nonconjugated diene monomers may be straight, branched or cyclic hydrocarbon dienes having 6 to 15 carbon atoms. Examples of suitable nonconjugated dienes include straight chain acyclic dienes such as 1,4-hexadiene, 1,6-octadiene, 1,7-octadiene, 1,9-decadiene, branched chain acyclic dienes such as 5 -Methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene; 3,7-dimethyl-1,7-octadiene and mixed isomers of dihydromyriene and dihydrooxyene, monocyclic alicyclic dienes such as 1,3-cyclopentadiene; 1,4-cyclohexadiene; 1,5-cyclooctadiene and 1,5-cyclododecadiene, and multicyclic alicyclic conjugated and bridged ring dienes such as tetrahydroindene, methyl tetrahydroindene, dicyclopentadiene, bicyclo- ( 2,2,1) -hepta-2,5-diene; Alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornene, such as 5-methylene-2-norbornene (MNB); 5-propenyl-2-norbornene, 5-isopropylidene-2-norbornene, 5- (4-cyclopentenyl) -2-norbornene, 5-cyclohexylidene-2-norbornene Butene, 5-vinyl-2-norbornene and norbornadiene. Among the dienes typically used for EPDM preparation, particularly preferred dienes are 1,4-hexadiene (HD), 5-ethylidene-2-norbornene (ENB), 5-vinylidene-2-norbornene (VNB ), 5-methylene-2-norbornene (MNB) and dicyclopentadiene (DCPD). Particularly preferred dienes are 5-ethylidene-2-norbornene (ENB) and 1,4-hexadiene (HD).

One class of preferred polymers that can be prepared according to the invention are elastomeric interpolymers of ethylene, C ₃ -C ₂₀ α-olefins, in particular propylene, and optionally one or more diene monomers. Preferred α-olefins for use in this embodiment of the invention are represented by the formula CH ₂ = CHR ^{* wherein} R ^* is a linear or branched alkyl group having from 1 to 12 carbon atoms. Examples of suitable α-olefins include, but are not limited to, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene. Particularly preferred α-olefins are propylene. Propylene based polymers are generally referred to in the art as EP or EPDM polymers. Suitable dienes for use in preparing such polymers, especially multiblock EPDM type polymers, include conjugated or nonconjugated, straight or branched chain, cyclic or polycyclic dienes comprising 4 to 20 carbons. Preferred dienes include 1,4-pentadiene, 1,4-hexadiene, 5-ethylidene-2-norbornene, dicyclopentadiene, cyclohexadiene and 5-butylidene-2-norbornene Include. Particularly preferred dienes are 5-ethylidene-2-norbornene.

Diene-containing polymers contain alternating segments or blocks containing more or less amounts of dienes (including if not present) and α-olefins (including if not present), thereby reducing diene without subsequent loss of polymer properties. And the total amount of α-olefins can be reduced. That is, since dienes and α-olefin monomers are predominantly incorporated into one type of polymer block rather than uniformly or randomly incorporated throughout the polymer, they are used more effectively, and the crosslinking density of the polymer can then be better controlled. . Such crosslinkable elastomers and cured products have advantageous properties, including higher tensile strength and better elastic recovery.

In some embodiments, interpolymers of the invention prepared by two catalysts incorporating different amounts of comonomer have a weight ratio of the blocks formed thereby from 95: 5 to 5:95. The elastomeric polymer preferably has 20 to 90% ethylene content, 0.1 to 10% diene content and 10 to 80% α-olefin content, based on the total weight of the polymer. More preferably, the multiblock elastomeric polymer has an ethylene content of 60 to 90%, a diene content of 0.1 to 10% and an α-olefin content of 10 to 40% based on the total weight of the polymer. Preferred polymers have a weight average molecular weight (M _w ) of 10,000 to about 2,500,000, preferably 20,000 to 500,000, more preferably 20,000 to 350,000, a polydispersity of less than 3.5, more preferably less than 3.0, Mooney) high molecular weight polymer having a viscosity (ML (1 + 4) 125 ° C.) of 1 to 250. More preferably, such polymers have an ethylene content of 65 to 75%, a diene content of 0 to 6% and an α-olefin content of 20 to 35%.

Ethylene / α-olefin interpolymers can be functionalized by incorporating one or more functional groups into their polymer structure. Examples of functional groups may include, for example, ethylenically unsaturated monofunctional and difunctional carboxylic acids, ethylenically unsaturated monofunctional and difunctional carboxylic anhydrides, salts thereof and esters thereof. Such functional groups may be grafted onto ethylene / α-olefin interpolymers or copolymerized with ethylene and any additional comonomers to form interpolymers of ethylene, functional comonomers and optionally other comonomer (s). Can be. Means for grafting functional groups onto polyethylene are described, for example, in US Pat. Nos. 4,762,890, 4,927,888 and 4,950,541, the disclosures of which are incorporated herein by reference in their entirety. One particularly useful group is maleic anhydride.

The amount of functional groups present in the functional interpolymer can vary. The functional group may typically be present in the copolymerized functionalized interpolymer in an amount of at least about 1.0 wt%, preferably at least about 5 wt%, more preferably at least about 7 wt%. The functional group is typically present in the copolymerized functionalized interpolymer in an amount of less than about 40 weight percent, preferably less than about 30 weight percent, more preferably less than about 25 weight percent.

Test method

In the following examples, the following analytical techniques were used.

For samples 1-4 and A-C GPC  Way

Using an automated liquid-handling robot equipped with a heated needle set at 160 ° C., sufficient 1,2,4-trichlorobenzene stabilized by 300 ppm Ionol was added to each dried polymer sample by 30 A final concentration of mg / mL was obtained. A small glass stir bar was placed in each tube and the sample was heated to 160 ° C. for 3 hours in a heated rotary shaker rotating at 250 rpm. The polymer concentrate was then diluted to 1 mg / ml using an automated liquid-handling robot and a heated needle set at 160 ° C.

Molecular weight data for each sample was measured using the Symyx Rapid GPC system. Helium purged 1,2-dichlorobenzene stabilized with 300 ppm ionol, using a Gilson 350 pump set at a flow rate of 2.0 ml / min, was placed in series with three Plgel 10 micrometers (μm) Pumped as a mobile phase through a Mixed-B 300 mm × 7.5 mm column and heated to 160 ° C. The Polymer Labs ELS 1000 Detector was placed at an evaporator set at 250 ° C., a nebulizer set at 165 ° C., and at a pressure of 60 to 80 psi (400 to 600 kPa) N ₂ . Used with nitrogen flow rate set to 1.8 SLM. The polymer samples were heated to 160 ° C. and each sample was injected into a 250 μl loop using a liquid-handling robot and heated needle. A series of polymer sample analyzes and duplicate injections using two switched loops were used. Sample data was collected and analyzed using Symyx Epoch (tradename) software. Peaks were manually integrated and molecular weight information was recorded uncorrected against the polystyrene standard calibration curve.

Standard CRYSTAF  Way

Branching distribution was measured by crystallization analysis fractionation (CRYSTAF) using a CRYSTAF 200 unit commercially available from Polymer Char (Valencia, Spain). The sample was dissolved in 1,2,4-trichlorobenzene at 160 ° C. for 1 hour (0.66 mg / mL) and stabilized at 95 ° C. for 45 minutes. Sampling temperatures ranged from 95 to 30 ° C. at a cooling rate of 0.2 ° C./min. The polymer solution concentration was measured using an infrared detector. The cumulative soluble concentration was measured when the polymer crystallized with decreasing temperature. Analytical derivatives of the cumulative profile reflect the short chain branching distribution of the polymer.

CRYSTAF peak temperature and area were confirmed by the peak analysis module included in the CRYSTAF software (version 2001.b, Polymer Char, Valencia, Spain). The CRYSTAF peak identification routine confirmed the area between the peak temperature as the maximum in the dW / dT curve, and the maximum amount of bend on each side of the peak identified in the derivative curve. To calculate the CRYSTAF curve, a preferred processing parameter is to perform parameter planarization above the temperature limit of 0.1 and below the temperature limit of 0.3 with a temperature limit of 70 ° C.

DSC  Standard method (except samples 1-4 and A-C)

The results of the differential scanning calorimetry were measured using a TAI model Q10OO DSC equipped with an RCS cooling accessory and an autosampler. A nitrogen purge gas flow of 50 ml / min was used. The sample was pressed into a thin film and melted in a press at about 175 ° C. and then air cooled to room temperature (25 ° C.). Subsequently, 3-10 mg of material was cut into 6 mm diameter disks, accurately weighed, placed in a lightweight aluminum pan (about 50 mg) and then crimped off. The thermal behavior of the samples was investigated with the following temperature profiles. The sample was rapidly heated to 180 ° C. and kept isothermal for 3 minutes to remove any previous thermal history. The sample was then cooled to −40 ° C. at a cooling rate of 10 ° C./min and held at −40 ° C. for 3 minutes. The sample was then heated to 150 ° C. at a heating rate of 10 ° C./min. Cooling and second heating curves were recorded.

The DSC melt peak was measured as the maximum of heat flow rate (W / g) with respect to the linear baseline shown between −30 ° C. and the melting end point. The heat of fusion was measured as the area under the melting curve between −30 ° C. and the melting end point using a linear baseline.

GPC  Method (except Samples 1-4 and A-C)

The gel permeation chromatography system consisted of a Polymer Laboratories Model PL-210 or a Polymer Laboratories Model PL-220 instrument. The column and carousel compartments were operated at 140 ° C. Three polymer Laboratories 10-micrometer Mixed-B columns were used. The solvent was 1,2,4-trichlorobenzene. Samples were prepared at a concentration of 0.1 grams of polymer in 50 milliliters of solvent containing 200 ppm of butylated hydroxytoluene (BHT). Samples were prepared by gently stirring at 160 ° C. for 2 hours. The injection volume used was 100 microliters and the flow rate was 1.0 ml / min.

Calibration of the set of GPC columns is carried out by 21 narrow molecular weight distribution polystyrene standards with molecular weights ranging from 580 to 8,400,000, arranged in six “cocktail” mixtures separated from each other by at least 10 individual molecular weights. It was. Standards were purchased from Polymer Laboratories, Shropshire, UK. Polystyrene standards were prepared in 0.025 grams in 50 milliliters of solvent for molecular weights greater than 1,000,000 and 0.05 grams in 50 milliliters of solvent for molecular weights less than 1,000,000. The polystyrene standard was dissolved at 80 ° C. with gentle stirring for 30 minutes. The narrow standard mixture was run first and then in decreasing order from the highest molecular weight component to minimize degradation. Equation: _Polyethylene standard peak molecular weight was converted to polyethylene molecular weight using M _polyethylene = 0.431 (M _polystyrene ) (Williams and Ward, J. Poym. Sci., Polym. Let., 6, 621 (1968)). Listed).

Polyethylene equivalent molecular weight was calculated using Viscotek TriSEC software version 3.0.

Compression set

Compression set was measured according to ASTM D 395. Samples were prepared by laminating circular discs of diameter 25.4 mm with a thickness of 3.2 mm, 2.0 mm and 0.25 mm until the total thickness reached 12.7 mm. The discs were cut from 12.7 cm x 12.7 cm compression molded plaques formed by hot press under the following conditions. A pressure of 0 at 190 ° C. for 3 minutes followed by 86 MPa at 190 ° C. for 2 minutes followed by cooling water at 86 MPa was cooled in the press.

density

Samples for density measurement were prepared according to ASTM D 1928. Measurements were made within 1 hour of sample compression using ASTM D792, Method B.

curve/ secant Modulus /Save Modulus

Samples were compression molded using ASTM D 1928. Flexural and 2% secant modulus were measured according to ASTM D-790. Storage modulus was measured according to ASTM D 5026-01 or equivalent technique.

Optical properties

A 0.4 mm thick film was compression molded using a hot press (Carver model # 4095-4PR1001R). The pellet was placed between polytetrafluoroethylene sheets and heated at 190 ° C. for 3 minutes at 55 psi (380 kPa) then 3 minutes at 1.3 MPa and then 3 minutes at 2.6 MPa. The film was then cooled in a press through which cooling water flowed at 1.3 MPa for 1 minute. Compression molded films were used for optical measurements, tensile behavior, recovery and stress relaxation rates.

Transparency was measured using BYK Gardner Haze-gard as specified in ASTM D 1746.

45 ° gloss was measured using BYK Gardner Glossmeter Microgloss 45 ° as specified in ASTM D-2457.

Internal haze was measured using a BYK Gardner Haze-Guard based on ASTM D 1003 Procedure A. Mineral oil was applied to the film surface to remove surface scratches.

Mechanical properties-tensile, Hysteresis ( Hysteresis ) And Tear

The stress-strain behavior at uniaxial tension was measured using ASTM D 1708 microtensile test specimens. Samples were stretched by Instron at 500C / min at 21 ° C. Tensile strength and elongation at break were recorded from the average of five test pieces.

100% and 300% hysteresis was measured from cyclic loading for 100% and 300% strain using an ASTM D 1708 microtensile test specimen by an Instron ™ instrument. Samples were loaded and unloaded at 21 ° C. at 267% / min for 3 cycles. Circulation experiments were performed at 300% and 80 ° C using an environmental chamber. In the 80 ° C. experiment, the samples were equilibrated for 45 minutes at the test temperature before testing. In a 21 ° C., 300% strain cycling experiment, shrinkage stress at 150% strain from the first unloading cycle was recorded. The percent recovery in all experiments was calculated from the first unloading cycle using the strain at which loading returned to baseline. Recovery rate (%) is defined as follows.

Where ε _f is the strain obtained for cyclic loading and ε _s is the strain at which the loading returns to the baseline during the first unloading cycle.

Stress relief was measured at 50% strain and 12 hours at 37 ° C. using an Instron ™ instrument equipped with an environmental chamber. The gauge geometry was 76 mm x 25 mm x 0.4 mm. After equilibrating at 37 ° C. for 45 minutes in an environmental chamber, the sample was stretched to 50% strain at 333% / min. The stress was recorded as a function of time for 12 hours. The stress relaxation rate (%) was calculated after 12 hours using the following equation.

In the formula, L ₀ is loading at 50% strain at 0 hours and L ₁₂ is loading at 50% strain after 12 hours.

Tensile notched tear experiments were performed with samples having a density of 0.88 g / cc or less using an Instron ™ instrument. The geometry consisted of a 76 mm x 13 mm x 0.4 mm gauge region with a 2 mm notch cut into the sample at half the test piece length. The sample was stretched to 508 mm / min at 21 ° C. until it broke. Tear energy was calculated as the area under the stress-elongation curve up to strain at maximum loading. The average of three or more test pieces was recorded.

TMA

Thermomechanical analysis (penetration temperature) was performed on compression molded discs of 30 mm diameter x 3.3 mm thickness, which were formed at 180 ° C. and 10 MPa molding pressure for 5 minutes and then air quenched. The instrument used was TMA 7 (trademark available from Perkin-Elmer). In the test, a probe with a radius of 1.5 mm (P / N N519-0416) was applied to the surface of the sample disc with a force of 1 N. The temperature was raised from 25 ° C. to 5 ° C./min. Probe penetration distance was measured as a function of temperature. The experiment was terminated when the probe had penetrated 1 mm into the sample.

DMA

Dynamic mechanical analysis (DMA) was performed on a compression molded disc that was formed in a hot press for 5 minutes at 180 ° C. and 10 MPa pressure and then water cooled to 90 ° C./min in the press. The test was performed using an ARES controlled strain rheometer (TA instrument) equipped with a double cantilever fixture for torsion testing.

1.5 mm plaques were pressed and cut into bars measuring 32 × 12 mm. Samples were clamped both ends between fixtures at 10 mm intervals (grip spacing (ΔL)) and a subsequent temperature step (5 ° C. per step) from −100 ° C. to 200 ° C. was performed. At each temperature, the torsional modulus (G ′) was measured at each frequency of 10 rad / s, and the strain amplitude was maintained between 0.1% and 4% to ensure that the torque was sufficient and the measurement was maintained in a linear manner.

An initial static force of 10 g was maintained (automatic tension mode) to prevent sagging in the sample when thermal expansion occurred. As a result, the grip spacing (ΔL) increased with temperature, especially at temperatures above the melting or softening point of the polymer sample. The test was stopped at the maximum temperature or when the gap between the fixtures reached 65 mm.

Melt index

Melt index or I ₂ was measured according to ASTM D 1238, Condition 190 ° C./2.16 kg. In addition, the melt index or I ₁₀ was measured according to ASTM D 1238, condition 190 ° C./10 kg.

ATREF

US Pat. No. 4,798,081 and Wilde, L .; Ryle, T. R .; Knobeloch, D. C .; Peat, I. R .; Determination of Branching Distributions in Polyethylene and Ethylene Copolymers, J. Polym. Sci., 20, 441-455 (1982), performed analytical temperature rising elution fractionation (ATREF) analysis. The composition to be analyzed was dissolved in trichlorobenzene and crystallized in a column containing an inert support (stainless steel shot) by slowly decreasing the temperature to 20 ° C. at a cooling rate of 0.1 ° C./min. The column was equipped with an infrared detector. The crystallized polymer sample was then eluted from the column by slowly increasing the temperature of the eluting solvent (trichlorobenzene) from 20 ° C. to 120 ° C. at a rate of 1.5 ° C./min to obtain an ATREF chromatogram curve.

¹³ C NMR  analysis

Samples were prepared by adding approximately 3 g of 50/50 mixture of tetrachloroethane-d ² / orthodichlorobenzene to 0.4 g of sample in a 10 mm NMR tube. The sample was dissolved and homogenized by heating the tube and its contents to 150 ° C. Data was collected using a JEOL Eclipse 400 MHz spectrometer or a Varian Unity Plus 400 MHz spectrometer, corresponding to a ¹³ C resonance frequency of 100.5 MHz. Data was acquired using 4000 transients per data file with a 6 second pulse repetition delay. To obtain the minimum signal-to-noise for quantitative analysis, multiple data files were added together. At a minimum file size of 32K data points, the spectral width was 25,000 Hz. Samples were analyzed at 130 ° C. in a 10 mm wide band probe. Randall's Randall's triad method (Randall, JC; JMS-Rev. Macromol. Chem. Phys., C29, 201-317 (1989)), which is hereby incorporated by reference in its entirety. Comonomer incorporation was measured.

TREF Polymer fractionation by

Large scale TREF fractionation was performed by dissolving 15-20 g of polymer at 160 ° C. for 4 hours and dissolving in 2 liters of 1,2,4-trichlorobenzene (TCB). The polymer solution is 30-40 mesh (600-425 μm) spherical industrial glass beads (available from Potters Industries, Brownwood HC 30 Box 20, 76801, USA) and diameter 0.028 "(0.7) mm) packed in a 60:40 (v: v) mixture of cut steel shorted stainless steel (available from Pellets, Inc., Industrial Drive 63, North Towanda, NY, USA 14120). Was added with 15 psig (100 kPa) of nitrogen on a 3 inch by 4 foot (7.6 cm x 12 cm) steel column, which was deposited into a thermally controlled oil jacket and initially set at 160 ° C. The column was first cooled rapidly to 125 ° C. and then slowly cooled to 0.04 ° C./min to 20 ° C. and held for 1 h.The temperature was increased to 0.167 ° C./min and fresh TCB was introduced at about 65 ml / min.

Approximately 2000 ml portions of the eluate from the preparative TREF column were collected in 16 zones of heated fraction collector. The polymer was concentrated in each fraction using a rotary evaporator until about 50-100 ml of polymer solution remained. After leaving the concentrate overnight, excess methanol was added, filtered and rinsed (approximately 300-500 ml of methanol, including the final rinse). The filtration step was performed in a three position vacuum assisted filtration zone using a 5.0 μm polytetrafluoroethylene coated filter paper (available from Osmonics Inc., Cat # Z50WP04750). The filtered fractions were dried overnight in a vacuum oven at 60 ° C., weighed on an analytical balance and then further tested.

Melt strength

Melt strength (MS) was measured using a capillary rheometer with a diameter of 2.1 mm and a 20: 1 die with an inlet angle of approximately 45 degrees. After equilibrating the sample at 190 ° C. for 10 minutes, the piston was run at a speed of 1 inch / minute (2.54 cm / minute). Standard test temperature was 190 ° C. Samples were uniaxially stretched with a set of acceleration nips located 100 mm below the die with an acceleration of 2.4 mm / sec ² . The required tensile force was recorded as a function of the winding speed of the nip rolls. The maximum tensile force achieved during the test is defined as the melt strength. When the polymer melt exhibits stretching resonance, the tensile force before the start of the stretching resonance is taken as the melt strength. Melt strength was reported in centinewtons (“cN”).

catalyst

When the term “overnight” is used, it refers to a time of approximately 16 to 18 hours, the term “room temperature” refers to a temperature of 20 to 25 ° C., and the term “mixed alkanes” is the trade name Iso from ExxonMobil Chemical Company. refers to a Parr (Isopar) E (R), available C _{6 -9} commercially available mixture of aliphatic hydrocarbons. If a compound name does not match its structural representation herein, the structural representation is governed. Synthesis of all metal complexes and preparation of all screening experiments were carried out in a dry nitrogen atmosphere using dry box technology. All solvents used were HPLC grade and they were used after drying.

MMAO refers to modified methylalumoxane, triisobutylaluminum modified methylalumoxane, commercially available from Akzo-Noble Corporation.

Preparation of the catalyst (B1) was carried out as follows.

a) (1- Methylethyl ) (2-hydroxy-3,5- Di (t-butyl) phenyl ) Methylimine  Produce

3,5-di-t-butylsalicylaldehyde (3.00 g) was added to 10 mL of isopropylamine. The solution rapidly turned bright yellow. After stirring for 3 hours at ambient temperature, the volatiles were removed under vacuum to yield a light yellow crystalline solid (yield 97%).

b) 1,2- Vis -(3,5-di-t- Butylphenylene ) (1- (N- (1- Methylethyl ) Imino ) methyl )(2- Oxoyl Zirconium Dibenzyl  Produce

A solution of (1-methylethyl) (2-hydroxy-3,5-di (t-butyl) phenyl) imine (605 mg, 2.2 mmol) in 5 mL toluene was added Zr (CH ₂ Ph) ₄ in 50 mL toluene. (500 mg, 1.1 mmol) was added slowly to the solution. The resulting dark yellow solution was stirred for 30 minutes. Removal of solvent under reduced pressure gave the desired product as a reddish brown solid.

Preparation of the catalyst (B2) was carried out as follows.

a) (1- (2- Methylcyclohexyl ) Ethyl) (2- Oxoyl -3,5- Di (t-butyl) phenyl Production of immigration

2-methylcyclohexylamine (8.44 mL, 64.0 mmol) was dissolved in methanol (90 mL) and di-t-butylsalicylaldehyde (10.00 g, 42.67 mmol) was added. The reaction mixture was stirred for 3 hours and then cooled to -25 ° C for 12 hours. The resulting yellow solid precipitate was collected by filtration, washed with cold methanol (2 × 15 mL) and then dried under reduced pressure. 11.17 g of a yellow solid were obtained. ¹ H NMR was consistent with the desired product as an isomer mixture.

b) Vis -(1- (2- Methylcyclohexyl ) Ethyl) (2- Oxoyl -3,5- Di (t-butyl) phenyl ) Imino )zirconium Dibenzyl  Produce

Zr in 600 mL toluene with a solution of (1- (2-methylcyclohexyl) ethyl) (2-oxoyl-3,5-di (t-butyl) phenyl) imine (7.63 g, 23.2 mmol) in 200 mL toluene To the solution of (CH ₂ Ph) ₄ (5.28 g, 11.6 mmol) was added slowly. The resulting dark yellow solution was stirred at 25 ° C. for 1 hour. The solution was further diluted with 680 mL toluene to give a solution with a concentration of 0.00783 M.

Cocatalyst 1: Substantially long-chain trialkylamines (Armeen® M2HT, Liquid-Nobel, Inc.), as disclosed in US Pat. No. 5,919,983, Example 2. Available from)), methyldi (C _14-18 alkyl) ammonium salt of tetrakis (pentafluorophenyl) borate (hereafter aluminum borate), prepared by reacting HCl and Li [B (C ₆ F ₅ ) ₄ ] ) Mixture.

Co-catalyst 2: U.S. Patent No. 6,395,671, Example 16 prepared according to, bis (tris (pentafluorophenyl) - aluminate only) -2-undecyl-mixing of the microporous Jolly DE C _{14 -18-alkyl} dimethyl ammonium salts.

Transfer agent : The transfer agent used was diethylzinc (DEZ, SA1), di (i-butyl) zinc (SA2), di (n-hexyl) zinc (SA3), triethylaluminum (TEA, SA4), trioctylaluminum ( SA5), triethylgallium (SA6), i-butylaluminum bis (dimethyl (t-butyl) siloxane) (SA7), i-butylaluminum bis (di (trimethylsilyl) amide) (SA8), n-octylaluminum di (Pyridine-2-methoxide) (SA9), bis (n-octadecyl) i-butylaluminum (SA10), i-butylaluminum bis (di (n-pentyl) amide) (SA11), n-octylaluminum bis (2,6-di-t-butylphenoxide) (SA12), n-octylaluminum di (ethyl (1-naphthyl) amide) (SA13), ethylaluminum bis (t-butyldimethylsiloxide) (SA14) , Ethylaluminum di (bis (trimethylsilyl) amide) (SA15), ethylaluminum bis (2,3,6,7-dibenzo-1-azacycloheptanamide) (SA16), n-octylaluminum bis (2, 3,6,7-dibenzo-1-azacycloheptanamide) (SA17), n-octylaluminum bis (dimethyl (t-butyl) Include hydroxide (SA18), ethyl zinc (2,6-diphenyl-phenoxide) (SA19), and zinc acetate (t- butoxide) (SA20).

Example  1 to 4, Comparative example  A to C

In general High throughput  Parallel polymerization condition

The polymerization is carried out using a high throughput parallel polymerization reactor (PPR) available from Simyx Technologies, Inc., and is substantially US Pat. No. 6,248,540, 6,030,917, 6,362,309. Work was performed in accordance with US Pat. No. 6,306,658 and 6,316,663. Ethylene copolymerization was carried out at 130 ° C. and 200 psi (1.4 MPa) with the required ethylene using 1.2 equivalents of cocatalyst 1 (1.1 equivalents when MMAO was present) based on the total catalyst used. A series of polymerizations was carried out in a parallel pressure reactor (PPR) containing 48 individual reactor cells in a 6 × 8 array with pre-weighed glass tubes fixed. The working volume in each reactor cell was 6000 μl. Each cell was stirred by a separate stirring paddle and temperature and pressure controlled. The monomer gas and the quench gas were plumbed directly into the PPR unit and controlled by an automatic valve. Liquid reagent was robotically added to each reactor cell by syringe, and the reservoir solvent was mixed alkanes. The order of addition was mixed alkane solvent (4 ml), ethylene, 1-octene comonomer (1 ml), cocatalyst 1 or cocatalyst 1 / MMAO mixture, transfer agent, and catalyst or catalyst mixture. When using a mixture of cocatalyst 1 and MMAO or a mixture of two catalysts, the premix was premixed in small vials just prior to adding the reagents to the reactor. If reagents were omitted from the experiment, the order of addition was maintained in a different way. The polymerization was carried out for approximately 1 to 2 minutes until the desired ethylene consumption was reached. After quenching with CO, the reactor was cooled and the glass tube was unloaded. The tube was transferred to a centrifuge / vacuum drying unit and dried at 60 ° C. for 12 hours. The tube containing the dried polymer was weighed and the net yield of the polymer was obtained from the difference between this weight and the container weight. The results are shown in Table 1. In Table 1 and elsewhere herein, the comparative compound is indicated by an asterisk (*).

Examples 1 to 4 show the products of a very narrow MWD, in particular monomodal copolymers, and also a broad molecular weight distribution of bimodal in the absence of DEZ (mixture of separately prepared polymers) in the presence of DEZ The synthesis of the linear block copolymers according to the invention, as evidenced by the formation of, is indicated. Due to the fact that catalyst (A1) is known to introduce more octenes compared to catalyst (B1), different blocks or segments of the resulting copolymers of the invention are distinguishable on the basis of branching or density.

¹ per 1000 carbon C _6, or higher chain content

² Bimodal Molecular Weight Distribution

The polymers prepared according to the invention have a relatively narrow polydispersity (M _w / M _n ) and higher block-copolymer content (trimers, tetramers or more) compared to polymers prepared in the absence of transfer agents. It can be seen.

Further characterization data for the polymers in Table 1 were determined with reference to the figures. More specifically, the DSC and ATREF results are shown below.

The DSC curve for the polymer of Example 1 showed a heat of fusion of 158.1 J / g and a melting point (Tm) of 115.7 ° C. The corresponding CRYSTAF curve shows the tallest peak at 34.5 ° C. and a peak area of 52.9%. The difference between the DSC Tm and the Tcrystaf was 81.2 ° C.

The DSC curve for the polymer of Example 2 showed a peak with a heat of fusion of 214.0 J / g and a melting point (Tm) of 109.7 ° C. The corresponding CRYSTAF curve shows the tallest peak at 46.2 ° C. and a peak area of 57.0%. The difference between the DSC Tm and the Tcrystaf was 63.5 ° C.

The DSC curve for the polymer of Example 3 showed a peak with a heat of fusion of 160.1 J / g and a melting point (Tm) of 120.7 ° C. The corresponding CRYSTAF curve shows the tallest peak at 66.1 ° C. and a peak area of 71.8%. The difference between the DSC Tm and the Tcrystaf was 54.6 ° C.

The DSC curve for the polymer of Example 4 showed a peak with a heat of fusion of 170.7 J / g and a melting point (Tm) of 104.5 ° C. The corresponding CRYSTAF curve shows the tallest peak at 30 ° C. and a peak area of 18.2%. The difference between the DSC Tm and the Tcrystaf was 74.5 ° C.

The DSC curve for Comparative Example A showed a heat of fusion of 86.7 J / g and a melting point (Tm) of 90.0 ° C. The corresponding CRYSTAF curve shows the tallest peak at 48.5 ° C. and the peak area of 29.4%. Both of these values were consistent with low density resins. The difference between the DSC Tm and the Tcrystaf was 41.8 ° C.

The DSC curve for Comparative Example B showed a heat of fusion of 237.0 J / g and a melting point (Tm) of 129.8 ° C. The corresponding CRYSTAF curve shows the tallest peak at 82.4 ° C. and the peak area of 83.7%. Both of these values were consistent with high density resins. The difference between the DSC Tm and the Tcrystaf was 47.4 ° C.

The DSC curve for Comparative Example C showed a heat of fusion of 143.0 J / g and a melting point (Tm) of 125.3 ° C. The corresponding CRYSTAF curve shows the highest peak at 81.8 ° C. and the peak area of 34.7% as well as the lower crystal peak at 52.4 ° C. The spacing between the two peaks was consistent with the presence of high and low crystalline polymers. The difference between DSC Tm and Tcrystaf was 43.5 ° C.

Example  5 to 19, Comparative example  D to F, continuous solution polymerization, catalyst A1 / B2 + DEZ

Continuous solution polymerization was carried out in a computer controlled autoclave reactor equipped with an internal stirrer. Purified mixed alkane solvent (Isopar ™ E) available from ExxonMobil Chemical Company, 2.70 lbs / hr (1.22 kg / hr) of ethylene, 1-octene and hydrogen (if used) were internal thermocouple and temperature It was fed to a 3.8 L reactor equipped with a control jacket. Solvent feed to the reactor was measured by a mass flow controller. A variable speed diaphragm pump was used to control the solvent flow rate and pressure into the reactor. On pump discharge, side flow was taken to provide flush flow for the catalyst and cocatalyst 1 injection line and reactor stirrer. These flows were measured by a Micro-Motion mass flow meter and adjusted by a control valve or by manual adjustment of the needle valve. The remaining solvent was combined with 1-octene, ethylene and hydrogen (if used) and fed to the reactor. If necessary, a mass flow controller was used to deliver hydrogen to the reactor. The temperature of the solvent / monomer solution was adjusted using a heat exchanger and then introduced into the reactor. The stream was introduced at the bottom of the reactor. The catalyst component solution was metered, combined with the catalyst flush solvent and introduced into the bottom of the reactor using a pump and a mass flow meter. The reactor was run in full liquid at 500 psig (3.45 MPa) with vigorous stirring. Product was removed through the outlet line at the top of the reactor. All outlet lines from the reactor were vapor traced and insulated. A small amount of water was added to the outlet line with any stabilizer or other additives and the polymerization was stopped by passing the mixture through a static mixer. The product stream was then heated through a heat exchanger and then devolatilized. The polymer product was recovered by extrusion using a devolatilization extruder and a water cooled pelletizer. Process details and results are listed in Table 2. Selected polymer properties are listed in Table 3.

^* Comparative Example (not an embodiment of the present invention)

¹ standard cm ³ / min

² [N- (2,6-di (1-methylethyl) phenyl) amido) (2-isopropylphenyl) (α-naphthalene-2-diyl (6-pyridine-2-diyl) methane)] hafnium dimethyl

³ bis- (1- (2-methylcyclohexyl) ethyl) (2-oxoyl-3,5-di (t-butyl) phenyl) imino) zirconium dibenzyl

⁴ molar ratio in reactor

⁵ Polymer Producing Rate

⁶ % conversion of ethylene in the reactor

⁷ Efficiency, kg polymer / g M (where g M = g Hf + g Zr)

The resulting polymer was tested by DSC and ATREF as in the above examples. The results are as follows.

The DSC curve for the polymer of Example 5 showed a peak with a heat of fusion of 60.0 J / g and a melting point (Tm) of 119.6 ° C. The corresponding CRYSTAF curve shows the tallest peak at 47.6 ° C. and a peak area of 59.5%. The delta between the DSC Tm and the Tcrystaf was 72.0 ° C.

The DSC curve for the polymer of Example 6 showed a peak with a heat of fusion of 60.4 J / g and a melting point (Tm) of 115.2 ° C. The corresponding CRYSTAF curve shows the tallest peak at 44.2 ° C. and the peak area of 62.7%. The delta between the DSC Tm and the Tcrystaf was 71.0 ° C.

The DSC curve for the polymer of Example 7 showed a peak with a heat of fusion of 69.1 J / g and a melting point of 121.3 ° C. The corresponding CRYSTAF curve shows the tallest peak at 49.2 ° C. and the peak area of 29.4%. The delta between the DSC Tm and the Tcrystaf was 72.1 ° C.

The DSC curve for the polymer of Example 8 showed a peak with a heat of fusion of 67.9 J / g and a melting point (Tm) of 123.5 ° C. The corresponding CRYSTAF curve shows the tallest peak at 80.1 ° C. and the peak area of 12.7%. The delta between the DSC Tm and the Tcrystaf was 43.4 ° C.

The DSC curve for the polymer of Example 9 showed a peak with a heat of fusion of 73.5 J / g and a melting point (Tm) of 124.6 ° C. The corresponding CRYSTAF curve shows the tallest peak at 80.8 ° C. and the peak area of 16.0%. The delta between the DSC Tm and the Tcrystaf was 43.8 ° C.

The DSC curve for the polymer of Example 10 showed a peak with a heat of fusion of 60.7 J / g and a melting point (Tm) of 115.6 ° C. The corresponding CRYSTAF curve shows the tallest peak at 40.9 ° C. and a peak area of 52.4%. The delta between the DSC Tm and the Tcrystaf was 74.7 ° C.

The DSC curve for the polymer of Example 11 showed a peak with a heat of fusion of 70.4 J / g and a melting point (Tm) of 113.6 ° C. The corresponding CRYSTAF curve shows the tallest peak at 39.6 ° C. and the peak area of 25.2%. The delta between the DSC Tm and the Tcrystaf was 74.1 ° C.

The DSC curve for the polymer of Example 12 showed a peak with a heat of fusion of 48.9 J / g and a melting point (Tm) of 113.2 ° C. The corresponding CRYSTAF curve did not show a peak above 30 ° C. (Thus, Tcrystaf was set to 30 ° C. for further calculation.) The delta between the DSC Tm and Tcrystaf was 83.2 ° C.

The DSC curve for the polymer of Example 13 showed a peak with a heat of fusion of 49.4 J / g and a melting point (Tm) of 114.4 ° C. The corresponding CRYSTAF curve shows the tallest peak at 33.8 ° C. and the peak area of 7.7%. The delta between the DSC Tm and the Tcrystaf was 84.4 ° C.

The DSC curve for the polymer of Example 14 showed a peak with a heat of fusion of 127.9 J / g and a melting point (Tm) of 120.8 ° C. The corresponding CRYSTAF curve shows the tallest peak at 72.9 ° C. and a peak area of 92.2%. The delta between the DSC Tm and the Tcrystaf was 47.9 ° C.

The DSC curve for the polymer of Example 15 showed a peak with a heat of fusion of 36.2 J / g and a melting point (Tm) of 114.3 ° C. The corresponding CRYSTAF curve shows the tallest peak at 32.3 ° C. and the peak area of 9.8%. The delta between the DSC Tm and the Tcrystaf was 82.0 ° C.

The DSC curve for the polymer of Example 16 showed a peak with a heat of fusion of 44.9 J / g and a melting point (Tm) of 116.6 ° C. The corresponding CRYSTAF curve shows the tallest peak at 48.0 ° C. and a peak area of 65.0%. The delta between the DSC Tm and the Tcrystaf was 68.6 ° C.

The DSC curve for the polymer of Example 17 showed a peak with a heat of fusion of 47.0 J / g and a melting point (Tm) of 116.0 ° C. The corresponding CRYSTAF curve shows the tallest peak at 43.1 ° C. and a peak area of 56.8%. The delta between the DSC Tm and the Tcrystaf was 72.9 ° C.

The DSC curve for the polymer of Example 18 showed a peak with a heat of fusion of 141.8 J / g and a melting point (Tm) of 120.5 ° C. The corresponding CRYSTAF curve shows the tallest peak at 70.0 ° C. and the peak area of 94.0%. The delta between the DSC Tm and the Tcrystaf was 50.5 ° C.

The DSC curve for the polymer of Example 19 showed a peak with a heat of fusion of 174.8 J / g and a melting point (Tm) of 124.8 ° C. The corresponding CRYSTAF curve shows the tallest peak at 79.9 ° C. and a peak area of 87.9%. The delta between the DSC Tm and the Tcrystaf was 45.0 ° C.

The DSC curve for the polymer of Comparative Example D showed a peak with a heat of fusion of 31.6 J / g and a melting point (Tm) of 37.3 ° C. The corresponding CRYSTAF curve did not show a peak above 30 ° C. Both of these values were consistent with low density resins. The delta between the DSC Tm and the Tcrystaf was 7.3 ° C.

The DSC curve for the polymer of Comparative Example E showed a peak with a heat of fusion of 179.3 J / g and a melting point (Tm) of 124.0 ° C. The corresponding CRYSTAF curve shows the tallest peak at 79.3 ° C. and a peak area of 94.6%. Both of these values were consistent with high density resins. The delta between the DSC Tm and the Tcrystaf was 44.6 ° C.

The DSC curve for Comparative Example F showed a peak with a heat of fusion of 90.4 J / g and a melting point (Tm) of 124.8 ° C. The corresponding CRYSTAF curve shows the tallest peak at 77.6 ° C. and the peak area of 19.5%. The spacing between the two peaks was consistent with the presence of both high and low crystalline polymers. The delta between the DSC Tm and the Tcrystaf was 47.2 ° C.

Property test

The polymer samples were evaluated for physical properties such as TMA temperature test, pellet block strength, hot recovery rate, hot compressive strain and storage modulus ratio (G '(25 ° C.) / G' (100 ° C.)). . Several commercial polymers were included in the test. Comparative Example G ^* was a substantially linear ethylene / 1-octene copolymer (Affinity® available from The Dow Chemical Company), and Comparative Example H ^* was a substantially linear ethylene / 1-octene elastomer air Coalescence (Affinity® EG8100 available from The Dow Chemical Company) and Comparative Example I was a substantially linear ethylene / 1-octene copolymer (Affinity® available from The Dow Chemical Company). PL1840), Comparative Example J was hydrogenated styrene / butadiene / styrene triblock copolymer (KRATON® G1652 available from KRATON Polymers), and Comparative Example K was a thermoplastic vulcanizate ( TPV, polyolefin blend with crosslinked elastomer dispersed therein). The results are shown in Table 4.

In Table 4, Comparative Example F (which is a physical blend of two polymers resulting from co-polymerization with Catalysts A1 and B1) has a 1 mm penetration temperature of about 70 ° C., while Examples 5-9 are 100 ° C. Had a penetration temperature of at least 1 mm. In addition, Examples 10-19 all had a 1 mm penetration temperature above 85 ° C., mostly with 1 mm TMA temperatures above 90 ° C. or even above 100 ° C. This shows that the new polymers have better dimensional stability at higher temperatures compared to the physical blends. Comparative Example J (commercial SEBS) had a good 1 mm TMA temperature of about 107 ° C., but had a very poor (high temperature 70 ° C.) compression set of about 100%, which also recovers 300% strain at high temperature (80 ° C.). Recovery failed (sample failure). Thus, the polymers exemplified had a unique combination of properties that could not be obtained even with some commercially available high performance thermoplastic elastomers.

Similarly, Table 4 shows a low (good) storage modulus ratio (G ′ (25 ° C.) / G ′ (100 ° C.)) of 6 or less for the polymers of the present invention, while the physical blend (Comparative Example F) The storage modulus ratio is 9 and similar density random ethylene / octene copolymers (Comparative Example G) show that the storage modulus ratio 89 is as large as the single-digit range. The storage modulus ratio of the polymer is preferably as close to 1 as possible. Such polymers are relatively unaffected by temperature, and articles made from such polymers can be usefully used over a wide temperature range. This low storage modulus ratio and temperature independence feature is particularly useful in elastomer applications such as pressure sensitive adhesive formulations.

The data in Table 4 also demonstrates that the polymers according to the invention have improved pellet blocking strength. In particular, Example 5 has a pelletized block strength of 0 MPa, which means free flow under test conditions compared to Comparative Examples F and G, which show significant blocking. Blocking strength is important because bulk transport of polymers with large blocking strength can result in cohesion or adhesion of the product with storage or dropping, resulting in poor handling.

The high temperature (70 ° C.) compression set of the polymers of the present invention is generally good, meaning that it is generally less than about 80%, preferably less than about 70%, in particular less than about 60%. In contrast, Comparative Examples F, G, H and J all had a 70 ° C. compression set of 100% (maximum possible, indicating no recovery). Good high temperature compression set (low values) is particularly necessary for applications such as gaskets, window profiles, o-rings, and the like.

^1. Tested at 51 cm / min.

^2. Measured at 38 ° C. for 12 hours.

Table 5 shows the results for the mechanical properties at ambient temperatures of the various polymers as well as the new polymers. It can be seen that the polymers of the invention have very good wear resistance when tested according to ISO 4649, which generally exhibits a volume loss of less than about 90 mm ³ , preferably less than about 80 mm ³ , in particular less than about 50 mm ^3. have. In this test, high values indicate high volume loss, and consequently low wear resistance.

As shown in Table 5, the tear strength measured by the tensile notch tear strength of the polymer of the present invention was generally 1000 mJ or more. The tear strength of the polymers of the invention can be as high as 3000 mJ, even as high as 5000 mJ. Comparative polymers generally had a tear strength of 750 mJ or less.

Table 5 also shows that the polymers according to the invention have better shrinkage stress at 150% strain (represented by higher shrinkage stress values) compared to some comparative samples. Comparative Examples F, G and H have a shrinkage stress value of 400 kPa or less at 150% strain, whereas the polymer of the present invention has a shrinkage stress value of 500 kPa (Example 11) to about 1100 kPa at 150% strain (Example 17). Polymers with higher 150% shrinkage stress values are very useful for elastic applications such as elastic fibers and fabrics, especially nonwovens. Other uses include diapers, hygiene and medical garment waistband articles such as tabs and elastic bands.

Table 5 also shows that the polymers of the present invention have an improved (lower) stress relaxation rate (at 50% strain) compared to Comparative Example G, for example. Low stress relaxation rate means that the polymer has a better effect in applications such as diapers and other garments where long term retention of elasticity at body temperature is desired.

Optical testing

The optical properties reported in Table 6 are based on compression molded films that are not substantially oriented. The optical properties of the polymer can vary over a wide range due to microcrystalline size changes resulting from changes in the amount of chain transfer agent used in the polymerization.

Extraction of Multiblock Copolymers

Extraction studies for the polymers of Examples 5, 7 and Comparative Example E were performed. In this experiment, polymer samples were weighed into a glass frit extraction thimble and placed in a Kumagawa type extractor. The extractor with sample was purged with nitrogen and a 50 mL round bottom flask was charged with 350 mL of diethyl ether. The flask was then fixed to the extractor. The ether was heated with stirring. The time at which the ether began to condense into the thimble was recorded and the extraction was run under nitrogen for 24 hours. At this time, heating was stopped and the solution was cooled. Any ether remaining in the extractor was returned to the flask. The ether in the flask was evaporated in vacuo at ambient temperature and the resulting solids were nitrogen purged dried. Any residue was transferred to a weighed bottle using hexane continuous wash. The combined hexane washes were then evaporated by further nitrogen purge and the residue was dried at 40 ° C. under vacuum overnight. Any ether remaining in the extractor was nitrogen purged dried.

Then, a second transparent round bottom flask filled with 35 mL of hexane was connected to the extractor. Hexane was stirred and heated to reflux and held at reflux for 24 hours after hexane was first observed to condense into the thimble. The heating was then stopped and the flask was cooled. Any hexane remaining in the extractor was transferred back to the flask. Hexane was removed by evaporation under vacuum at ambient temperature and any residue remaining in the flask was transferred to a weighed bottle using hexane continuous wash. Hexane in the flask was evaporated by nitrogen purge and the residue was vacuum dried at 40 ° C. overnight.

The polymer sample remaining in the thimble after extraction was transferred from the thimble to a weighed bottle and vacuum dried overnight at 40 ° C. The results are shown in Table 7.

Additional polymers Example  19A-J, continuous solution polymerization, catalyst A1 / B2 + DEZ

Example  19A to I

Continuous solution polymerization was carried out in a computer controlled well mixed reactor. Purified mixed alkane solvent (Isopar ™ E) available from ExxonMobil Inc., ethylene, 1-octene and hydrogen (if used) were combined and fed to a 27 gallon reactor. The feed to the reactor was measured by a mass flow controller. The temperature of the feed stream was controlled using a glycol cooled heat exchanger and then introduced to the reactor. The catalyst component solution was metered using a pump and a mass flow meter. The reactor was run in full liquid at approximately 550 psig. Drained from the reactor, water and additives were injected into the polymer solution. The polymerization was terminated by hydrolysis of the catalyst with water. The post reactor solution was then heated to prepare for two stage devolatilization. The solvent and unreacted monomers were removed during the devolatilization process. The polymer melt was pumped into a die for cutting pellets underwater.

Example  19J

Continuous solution polymerization was carried out in a computer controlled autoclave reactor equipped with an internal stirrer. Purified mixed alkanes solvent (Isopar® E) available from ExxonMobil Chemical Company, 2.70 lb / hr (1.22 kg / hr) of ethylene, 1-octene and hydrogen (if used) were subjected to a temperature control jacket and It was fed to a 3.8 L reactor equipped with an internal thermocouple. Solvent feed to the reactor was measured by a mass flow controller. A variable speed diaphragm pump was used to control the solvent flow rate and pressure into the reactor. On pump discharge, side flow was taken to provide flush flow for catalyst and cocatalyst injection lines and reactor stirrers. These flows were measured by a micro-motion mass flow meter and controlled by a control valve or by manual adjustment of the needle valve. The remaining solvent was combined with 1-octene, ethylene and hydrogen (if used) and fed to the reactor. If necessary, a mass flow controller was used to deliver hydrogen to the reactor. The temperature of the solvent / monomer solution was adjusted using a heat exchanger and then introduced into the reactor. The stream was introduced at the bottom of the reactor. The catalyst component solution was metered, combined with the catalyst flush solvent and introduced into the bottom of the reactor using a pump and a mass flow meter. The reactor was run in full liquid at 500 psig (3.45 MPa) with vigorous stirring. Product was removed through the outlet line at the top of the reactor. All outlet lines from the reactor were vapor traced and insulated. A small amount of water was added to the outlet line with any stabilizer or other additives and the polymerization was stopped by passing the mixture through a static mixer. The product stream was then heated through a heat exchanger and then devolatilized. The polymer product was recovered by extrusion using a devolatilization extruder and a water cooled pelletizer.

Process details and results are listed in Table 8. Selected polymer properties are listed in Tables 9A-9C.

In Table 9B, Examples 19F and 19G of the present invention show a low instantaneous strain of approximately 65-70% after 500% elongation.

¹ standard cm ³ / min

² [N- (2,6-di (1-methylethyl) phenyl) amido) (2-isopropylphenyl) (α-naphthalene-2-diyl (6-pyridine-2-diyl) methane)] hafnium dimethyl

³ bis- (1- (2-methylcyclohexyl) ethyl) (2-oxoyl-3,5-di (t-butyl) phenyl) imino) zirconium dimethyl

⁴ ppm in the final product calculated by mass balance

⁵ Polymer Producing Rate

⁶ % conversion of ethylene in the reactor

⁷ Efficiency, kg polymer / g M (where g M = g Hf + g Z)

Ethylene / α-olefin Multiblock Interpolymer Component (s) Particularly Useful in Compositions with Improved High Temperature Tackiness

Some ethylene / α-olefin multiblock interpolymers have been found to be particularly advantageous for compositions suitable for films. For example, particularly useful ethylene / α-olefin multiblock interpolymers (when measured according to ASTM D-792) have a density generally greater than about 0.860 g / cc, preferably between about 0.89 g / cc and about 0.94 g. / cc, more preferably about 0.887 g / cc to about 0.928 g / cc, even more preferably about 0.900 g / cc to about 0.925 g / cc. Interpolymers of this density can be used alone or in combination with other polymers to produce compositions having improved high temperature tack properties.

Similarly, the molecular weight of the aforementioned ethylene / α-olefin multiblock interpolymers should generally be considered when selecting such interpolymers for the given film applications. The molecular weight of the interpolymers is conveniently presented using melt index measurements according to ASTM D-1238, Condition 190 ° C./2.16 kg (formerly known as “Condition E” and also known as I ₂ ). Melt index is inversely proportional to the molecular weight of the polymer. Thus, although these relationships are not linear, the higher the molecular weight, the smaller the melt index. Melt indices for such interpolymers that may be particularly useful in film compositions generally range from about 0.1 g / 10 minutes to about 10 g / 10 minutes, preferably from about 0.2 g / 10 minutes to about 5 g / 10 minutes, in particular From about 0.5 g / 10 minutes to about 3 g / 10 minutes. These melt index interpolymers may be used alone or in combination with other polymers to produce compositions suitable for films with advantageous properties.

Compositions Comprising Ethylene / α-Olefin Multiblock Interpolymer Component (s) With High Hot Tackiness

The particular composition chosen for a given film will often depend on the type of film, the number of layers, its intended use and desired properties. In addition to high temperature tack, such properties may include, for example, processing, strength or adhesion characteristics. By using a suitable composition comprising one or more of the ethylene / α-olefin multiblock interpolymers described above, an improved performance or improved combination of the desired properties of the film can be obtained.

In a preferred embodiment, a composition comprising one of the above described ethylene / α-olefin multiblock interpolymers can be used. Alternatively, compositions comprising two or more of the ethylene / α-olefin multiblock interpolymers described above, each having one or more different properties, may be used. Other alternatives include one or more of the ethylene / α-olefin multiblock interpolymers described above, incorporating one or more other polymers, such as substantially linear ethylene interpolymers or homopolymers (SLEP), high pressure low density polyethylene (LDPE), ethylene / vinyl acetate Copolymers (EVA), ethylene / carboxylic acid copolymers and ionomers thereof, polybutylene (PB), and α-olefin polymers such as high density polyethylene, medium density polyethylene, polypropylene, ethylene / propylene interpolymers, linear low density polyethylene (LLDPE) and ultra low density polyethylene as well as graft-modified polymers, and combinations thereof (eg, density, MWD and / or comonomers as disclosed by Smith in US Pat. No. 5,032,463, incorporated herein by reference). And combinations). In multilayer films, in some cases, the outer film layer (otherwise referred to as "surface layer" or "surface layer") and / or sealant layer is an ethylene / α-olefin multiblock interpolymer, a substantially linear ethylene interpolymer And / or homopolymers, or mixtures thereof.

Preferred compositions for films often vary depending on the desired properties, but often ethylene / α-olefin multiblock interpolymers are at least about 20%, more preferably at least about 30%, more preferably based on the total weight of the composition Preferably at least about 50% by weight. Often, it is desirable to include additional polymers or polymer blends made by Ziegler catalysts, constrained geometry catalysts, or combinations thereof. Particularly useful further polymers are described, for example, in US Pat. No. 5,844,045; 5,847,053; US Pat. 6,111,023; 6,111,023; And SLEP, LLDPE, LDPE, polypropylene and blends thereof, as described in US Pat. No. 6,262,174. Such polymers are marketed, for example, by Dow Chemical Company and Exxon under the trade names Affinity®, Elite®, Dowlex® and Igjax®. The compositions of the present invention are also compatible and are particularly suitable for blends with HDPE which are often used as film barrier layers. In addition, blends comprising polypropylene and LDPE can achieve even better high temperature tack properties in some cases as described in US Pat. No. 6,262,174. For cases where an easily openable bag is desired, a heat sealable film layer comprising an ethylene / α-olefin multiblock interpolymer and a polybutylene or other butylene polymer compatible with the ethylene / α-olefin multiblock interpolymer It may be desirable to use.

The composition may be formed by any conventional method, including those described in US Pat. No. 6,262,174, which is incorporated herein by reference in its entirety. For example, the blend can be prepared by mixing or kneading each of the components at or near the melting point temperature of one or more of the components. For most ethylene / α-olefin multiblock interpolymer compositions, such temperatures may be above 130 ° C., most generally above 145 ° C., and most preferably above 150 ° C. Conventional polymer mixing or kneading apparatus can be used which can reach the desired temperature and melt plasticize the mixture. This includes mills, kneaders, extruders (both single and twin screw), Banbury mixers, calenders and the like. Mixing order and method may vary depending on the final composition. Combinations of Banbury batch mixers and continuous mixers may be used, such as Banbury mixers, then wheat mixers, and then extruders.

Another method of forming the composition is Brian W., which is incorporated herein by reference in its entirety. s. Brian WS Kolthammer and Robert S. In situ polymerization as disclosed in US Pat. No. 5,844,045 under the name Robert S. Cardwell. U. S. Patent No. 5,844, 045 describes interpolymerization of ethylene and C ₃ -C ₂₀ α-olefins using one or more homogeneous catalysts in one or more reactors and one or more heterogeneous catalysts in one or more other reactors. Multiple reactors may be operated continuously or in parallel, or in any combination thereof, and one or more reactors are used to prepare the ethylene / α-olefin multiblock interpolymers described above. In this manner, the blend can be prepared by a solution process comprising constrained geometry catalysts, Ziegler catalysts, and combinations thereof. Such blends include, for example, one or more ethylene / α-olefin multiblock interpolymers (as described above and in PCT / US2005 / 008917, filed March 17, 2004), one or more broad molecular weight distribution polymers ( For example, heterogeneously branched ethylene polymers described in US Pat. No. 5,847,053), and / or polymers of one or more narrow molecular weight distributions (e.g., homogeneous polymers described in US Pat. No. 3,645,992 (Elston) or US Pat. No. 5,272,236). ).

In situ polymerization using a continuous solution polymerization reactor may be particularly desirable when producing blends comprising at least one high molecular weight polymer having a wide molecular weight distribution and at least one polymer having a narrow molecular weight distribution made with a Ziegler catalyst. This is because the use of Ziegler catalysts often requires higher temperatures than homogeneous catalysts, while substantial solvents are often needed to produce high molecular weight polymers. Thus, the use of higher temperatures with Ziegler catalysts in subsequent reactors will promote excess solvent evaporation. In addition, another advantage of using a continuous solution reactor to produce the product of the present invention is that a highly reactive reactor attachment, even if very high molecular weight products (eg, I ₂ of 0.05 g / 10 min or less) is often not physically isolated. Ultra-high molecular weight products can be prepared and incorporated into the final product without. Thus, in the "blend" in which the ultrahigh molecular weight component is incorporated, separate or physical blends are often not even possible because the first component cannot be isolated.

Other general guidelines can be used by those skilled in the art to select compositions for films with the desired properties. For example, it has been found that ethylene / a-olefin multiblock interpolymers prepared with higher amounts of chain transfer agents tend to exhibit lower onset temperatures and wider hot adhesion windows.

Depending on the amount and type of chain transfer agent used to prepare the ethylene / α-olefin multiblock interpolymers, the compositions of the present invention may further comprise residues of the chain transfer agent (s) used. Residue means an analytically detectable amount of the original chain transfer agent or derivative thereof, such as a zinc or aluminum compound.

Useful additives

Antioxidants (e.g., hindered phenols (e.g., Ciba Geigy under the trade name Irganox.RTM. 1010 or Irganox. RTM. 1076), phosphites (e.g. under the trade name Ciba Geigy) Irgafos.RTM. 168)], processing aids, adhesive additives (e.g. PIB), PEPQ (trade name) (trade name of Sandoz Chemical, its main component being considered biphenylphosphonite) ), Clay fluids, pigments, colorants, fillers and the like can also be included in the composition to the extent that it does not interfere with the desired properties. The films produced include, but are not limited to, non-treated and treated silicon dioxide, talc, calcium carbonate and clay, as well as primary and secondary fatty acid amides, silicone coatings, etc. It may also contain additives. Other additives may also be added to enhance the antistatic properties of the film, eg, as described in US Pat. No. 4,486,552 (Niemann), the disclosure of which is incorporated herein by reference. Other additives, such as quaternary ammonium compounds, may also be added alone or in combination with EAA or other functional polymers in order to enhance the antistatic properties of the film and make it available for packaging of electronic sensing products.

Heat sealable film made from the composition of the present invention

Films made from the compositions of the present invention advantageously have desirable properties such as good sealing strength, low onset temperature, high extreme high temperature tack and wide processing windows. For example, 2 mil single layer blown films made from the compositions of the present invention are often tested in ASTM F 1921, a high temperature seal strength (hot tack) of blends and thermoplastic polymers that include the sealing surface of a flexible web. More than about 1 N / in, preferably greater than about 2 N / in, more preferably greater than about 3 N / in, even more preferred based on the method, Method B having a residence time of 0.5 seconds and a cooling time of 0.1 seconds. Has a high high temperature tack greater than about 4 N / in, such as extreme high temperature tack. Ultimate (or peak) hot tack strength is typically obtained at a sealing temperature of at least about 15, preferably at least about 20 ° C. below the polymer's peak melting temperature as measured by DSC. 2 mil monolayer films made from the compositions of the invention are also often at least about 20 ° C., more preferably at least about 30 ° C., based on ASTM F 1921, Method B having a residence time of 0.5 seconds and a cooling time of 0.1 seconds. It preferably has a high temperature tack of greater than 1 N / in over a temperature range of at least about 40 ° C., even more preferably at least about 45 ° C. Seal strength is typically greater than about 3.75 lb / in, preferably greater than about 3.9 lb / in, more preferably greater than about 4 lb / in when using ASTM F88, standard test method for sealing strength of flexible barrier materials Even more preferably greater than about 4.1 lb / in.

The hot tack temperature window is defined herein as a temperature window in which the hot tack strength of the joint exceeds a certain value, such as 0.5 N / linear inch.

The wide hot tack temperature window of the composition of the present invention often begins substantially lower than the peak melting temperature through DSC of the composition, such as about _25 ° C. or higher, preferably about _35 ° C. or lower. As a comparison, the comparative example shows a hot tack initiation temperature of more than 0.5 N / linear inch at a temperature about 10-15 ° C. below the peak melting temperature via DSC. This allows the inventor to easily adjust the desired seal strength by varying the seal temperature such that the seal strength and hot tack strength are balanced. This property also makes this possible in applications requiring higher temperature resistance, such as vacuum sterilization of packaged food.

Heat sealable films made from the compositions of the present invention can be used in single layer or multilayer film structures, or as laminates. Multilayer film structures are preferred. Regardless of how the film is used, it can be produced by a variety of methods well known to those skilled in the art.

Film structures can be produced by conventional manufacturing techniques such as simple bubble extrusion, biaxial orientation methods (such as tenter frames or double bubble methods), single cast / sheet extrusion, coextrusion, lamination, and the like. Conventional simple bubble extrusion methods (also known as hot blown film processes) are described, for example, in Encyclopedia of Chemical Technology, Kirk-Othmer, Third Edition, John Wiley & Sons, New York, 1981, Vol. 16, pp. 416-417 and Vol. 18, pp. 191-192.

"Elongated" and "oriented" are used interchangeably in the art and herein, but in practice the orientation is the result of elongation of the film, for example by forcing internal air into the tube or pulling the tenter frame on the edge of the film. to be.

Methods of making biaxially oriented films, such as the “double bubble” method of US Pat. No. 3,456,044 (Falke), and US Pat. No. 4,352,849 (Mueller), US Pat. No. 4,820,557 and each incorporated herein by reference. 4,837,084 (both Warren), U.S. Patent 4,865,902 (Golike et al.), U.S. Patent 4,927,708 (Herran et al.), U.S. Patent 4,952,451 (Muller) and U.S. Patents The methods described in US Pat. Nos. 4,963,419 and 5,059,481 (both Lustig et al.) Can also be used to prepare the novel film structures of the present invention. Biaxially oriented film structures can also be made with tenter frame techniques such as those used for oriented polypropylene.

Compared to the simple bubble method, the "double bubble" or "trapped bubble" film process disclosed by Falque in US Pat. No. 3,456,044 can significantly increase the orientation of the film in both the longitudinal and transverse directions. Increased orientation results in higher free shrinkage when the film is subsequently heated. Also, Falke is in US Pat. No. 3,456,044, and Rosig et al. In US Pat. No. 5,059,481 (incorporated herein by reference). Poor longitudinal when low density polyethylene and ultra low density polyethylene materials are produced by the simple bubble method, respectively. And transverse shrinkage properties such as about 3% free shrinkage in both directions. However, in contrast to known film materials, in particular US Pat. No. 5,059,481 to Lustig et al .; 4,976,898; 4,976,898; And in contrast to those disclosed in US Pat. No. 4,863,769, and in US Pat. No. 5,032,463 (all incorporated herein by reference), the special interpolymer compositions of the present invention are substantially both in longitudinal and transverse directions. It can show improved simple bubble shrinkage properties. In addition, special interpolymers are disclosed in US Pat. No. 3,456,044 by high blow-up ratios, such as simple bubble methods of 2.5: 1 or more, or more preferably by Falke, and in US Pat. No. 4,976,898 by Rustig et al. When produced by the “double bubble” process, good longitudinal and transverse shrinkage properties can be achieved so that the resulting film can be suitable for shrink wrap packaging purposes. The blow-up ratio, abbreviated herein as “BUR”, is calculated by the following formula.

BUR = Bubble Diameter / Die Diameter

The olefin packaging and wrapping film made from the composition of the present invention may be a single layer or multilayer film. Films made from the novel compositions can also be coextruded with other layer (s), or the films can be found in Packaging Foods With Plastics, by Wilmer A. Jenkins and James P. Harrington (1991). Or ["Coextrusion For Barrier Packaging" by WJ Schrenk and CR Finch, Society of Plastics Engineers RETEC Proceedings, Jun. 15-17 (1981), pp. 211-229 or ["Coextrusion Basics" by Thomas I. Butler, Film Extrusion Manual: Process, Materials, Properties. Laminated on another layer (s) in a secondary operation such as described in pp.31-80 (published by TAPPI Press (1992)). Monolayer films are incorporated herein by reference. R. Osborn and WA Jenkins in "Plastic Films, Technology and Packaging Applications" (Technomic Publishing Co., Inc. (1992)), tubular films (ie, blown film techniques), or flat dies (ie, When produced through a cast film), the film can only form a multi-layered structure through a further post extrusion step of adhesion to another layer of packaging material or extrusion lamination. If the film is a coextrusion of two or more layers (also described by Osborn and Jenkins), the film can still be laminated to an additional layer of packaging material according to the other physical requirements of the final film. have. Lamination vs. coextrusion is also discussed in "Laminations Vs. Coextrusion" by D. Dumbleton (Converting Magazine (September 1992), which is incorporated herein by reference. For example, the biaxial orientation method can be performed.

In certain embodiments of the invention, the at least one heat sealable innermost or outermost layer (ie, surface layer) of the film structure comprises at least one ethylene / α-olefin multiblock interpolymer. Such a heat sealable layer may be coextruded with other layer (s), or the heat sealable layer may be described in Packaging Foods With Plastics, supra or "Coextrusion For Barrier Packaging" by WJ. Schrenk and CR Finch, Society of Plastics Engineers RETEC Proceedings, June 15-17 (1981), pp. 211-229 may be laminated on another layer (s) or substrate in a secondary operation such as described. Preferred substrates include paper, foil, industrial grade or oriented polypropylene, polyamide, polyester, polyethylene, polyethylene terephthalate, and metallized substrates such as BICOR LBW.RTM.

If a multilayer film is desired, it is described in K. K. R. Osborn and WA Jenkins in "Plastic Films, Technology and Packaging Applications" (Technomic Publishing Co., Inc. (1992)), tubular films (ie, blown film techniques), or flat dies (ie, Cast film) from the previously produced monolayer film, the sealant film must undergo a further post-extrusion step of adhesion or extrusion lamination to another layer of packaging material. If the sealant film is a coextrusion of two or more layers (also described by Osborn and Jenkins), the film is still in an additional layer of packaging material according to the other physical requirements of the final packaging film. It can be laminated. Lamination vs. coextrusion is also discussed in "Laminations Vs. Coextrusion" by D. Dumbleton (Converting Magazine (September 1992), which is incorporated herein by reference. For example, a biaxial orientation method and irradiation can be carried out, in the case of irradiation, the technique can be preceded by extrusion by feeding the pellets to be made into the film prior to feeding the extruder, which increases the melt tension of the extruded polymer film and Improve processability

Extrusion coating is another technique for making packaging materials. Similar to cast films, extrusion coating is a flat die technique. Heat-sealable films made of the compositions of the present invention may be extrusion coated onto a substrate in the form of a monolayer or coextruded extrudate, for example, according to the method described in US Pat. No. 4,339,507, which is incorporated herein by reference. have. By multiple passes through various substrates through multiple extruders or through an extrusion coating system, multiple polymer layers are created that each provide some sort of performance property of barrier, toughness, or improved hot tack or heat sealability. can do. Some typical end uses for multilayered / multi-based systems are for cheese packaging. Other end uses include, but are not limited to, wet pet food, snacks, chips, frozen foods, meat, hot dogs, and many other uses.

Generally for multilayer film structures, the novel compositions described herein constitute one or more layers of the total multilayer film structure. Other layers of the multilayer structure can be included to provide various performance attributes. Other layers of the multilayer structure include, but are not limited to, barrier layers and / or junction layers and / or structural layers. Various materials may be used for these layers, some of which may be used as one or more layers in the film structure. Some of these materials are foil, nylon, ethylene / vinyl alcohol (EVOH) copolymers, poly (ethylene terephthalate) (PET), polyvinylidene chloride (PVDC), polyethylene terephthalate (PET), oriented polypropylene (OPP) Ethylene / vinyl acetate (EVA) copolymers, ethylene / acrylic acid (EAA) copolymers, ethylene / methacrylic acid (EMAA) copolymers, LLDPE, HDPE, LDPE, nylon, graft adhesive polymers (eg, maleic anhydride grafted Polyethylene), styrene-butadiene polymers (eg, K-resins available from Phillips Petroleum) and paper. In general, the multilayer film structure includes from 2 to about 7 layers.

The thickness of the multilayer structure is typically from about 0.5 mils to about 4 mils (total thickness). The heat sealable film layer varies in thickness depending on whether it is produced through coextrusion or lamination of a single layer or coextruded film to other packaging materials. In coextrusion, the heat sealable film layer is typically from about 0.1 to about 3 mils, preferably from about 0.4 to about 2 mils. In the laminated structure, the monolayer or coextruded heat sealable film layer is typically about 0.5 to about 2 mils, preferably about 1 to 2 mils. For monolayer films, the thickness is typically from about 0.4 mils to about 4 mils, preferably from about 0.8 to about 2.5 mils.

The heat sealable film of the present invention can be made into a packaging structure such as a mold-fill-sealing structure or a bag-in-box structure. For example, one such molding-filling-sealing operation is described in Packaging Foods With Plastics, ibid, pp. 78-83. Packaging materials are also described in "Packaging Machinery Operations: No. 8, Form-Fill-Sealing, A Self-Instructional Course" by C. G. Davis, Packaging Machinery Manufacturers Institute (April 1982); The Wiley Encyclopedia of Packaging Technology by M. Bakker (Editor), John Wiley & Sons (1986), pp. 334, 364-369; And Packaging: An Introduction by S. Sacharow and A. L. Brody, Harcourt Brace Javanovich Publications, Inc. (1987), pp. 322-326, which may be formed from a multilayer packaging roll stock by vertical or horizontal mold-fill-sealed packaging and thermoform-fill-sealed packaging. The disclosures of all of these documents are incorporated herein by reference. A particularly useful device for the mold-fill-sealing operation is the Hayssen Ultima Super CMB Vertical mold-fill-sealing machine. Other manufacturers of pouch thermoforming and vacuum devices are Cryovac and Koch. Methods of making pouches using vertical mold-fill-sealing machines are generally described in US Pat. Nos. 4,503,102 and 4,521,437, both of which are incorporated herein by reference. Film structures containing one or more layers comprising the heat sealable film of the present invention are well suited for packaging portable water, wine, cheese, potatoes, seasonings and similar food products in such mold-fill-sealed structures.

Film structures made from both the interpolymers described herein can also be preformed by any known method, such as, for example, extrusion thermoforming, on the shape and contour of the product to be packaged. The advantage of using preformed film structures will make it possible to supplement or avoid certain provided packaging operations such as increased drawability, reduced film thickness for a given draw condition, reduced heat up time and cycle time and the like.

Film structures made from both the ethylene / a-olefin multiblock interpolymers described herein show surprisingly more efficient irradiation crosslinking compared to conventional conventional Ziegler polymerized linear ethylene / a-olefin polymers. In accordance with one aspect of the present invention, the use of efficient irradiation of the unique polymer enables the production of film structures with differentially or selectively crosslinked film layers. To further exploit this finding, certain film layer materials comprising the ethylene / α-olefin multiblock interpolymers of the present invention may be prepared by Warren, such as proallyl cyanurate, described in US Pat. No. 4,957,790. (pro-rad agent), and / or Evert et al. can be combined with antioxidant crosslinking inhibitors such as butylated hydroxytoluene described in US Pat. No. 5,055,328.

Irradiation crosslinking is also useful for increasing the shrinkage temperature range and heat seal range for the film structure. For example, US Pat. No. 5,089,321, incorporated herein by reference, discloses a multilayer film structure comprising one or more heat sealable outer layers and one or more core layers having good irradiation crosslinking performance. Among the irradiation crosslinking techniques, beta ray irradiation with an electron beam source and gamma ray irradiation with radioactive elements such as cobalt 60 are the most common methods of crosslinking film materials.

In the irradiation crosslinking method, a thermoplastic film is prepared by a blown film process and then crosslinked with a polymeric film by exposure to a radiation source (beta or gamma) of 20 Mrad or less of irradiation dose. However, irradiation crosslinking can be induced before and after the final film orientation at any time if the oriented film is required, for example, for shrinkage and surface packaging, preferably irradiation crosslinking is induced before the final orientation. If a heat-shrinkable and surface wrapping film is produced by a process in which pellet or film irradiation occurs before final film orientation, the film will always exhibit higher shrinkage tension and will be likely to cause higher packaging warpage and board curl, and vice versa. If the orientation occurs before irradiation, the resulting film will exhibit lower shrinkage tension. Unlike shrinkage tensile, the free shrinkage properties of the ethylene / α-olefin multiblock interpolymers of the present invention are believed to be essentially unaffected whether the irradiation occurs before or after the final film orientation.

Irradiation techniques useful for treating the film structures described herein include techniques known to those skilled in the art. Preferably, irradiation is achieved by using an electron beam (beta) irradiation apparatus in a dose of about 0.5 Megarad (Mrad) to about 20 Mrad. Shrink film structures made from the ethylene / α-olefin multiblock interpolymers described herein are also expected to exhibit improved physical properties because of the lower degree of chain breakage that occurs as a result of irradiation treatment.

The interpolymers, blends and films of the present invention, and methods of making them are more fully described in the Examples below.

Of the present invention Example  1-2- Monolayer Blown  film

The ethylene-octene and ethylene-butene multiblock interpolymers used in Examples 1 and 2 below give priority to US Provisional Application No. 60 / 553,906, filed March 17, 2004, each of which is incorporated herein by reference. Prepared as described in PCT Application No. PCT / US2005 / 008917, filed March 17, 2005, claimed. A comparative example is a random ethylene-octene copolymer made using a restrained geometry catalyst such as sold under the tradename Affinity® by Dow Chemical Company. The polymer has a melt index of about 1 g / 10 minutes.

Single layer blown films of the olefin block copolymers and the comparative examples provide three Davis-Standard (Lavi-D) ratios with an L / D ratio of 24: 1, giving a 2-inch diameter blown die with a nominal 0.033 die gap. Standard) was prepared using a Davis-Standard blown film extrusion line equipped with a model DS075HM 3/4 "inch extruder. The discharge rate was about 2.8 pounds / hour or 0.05 lb / hour / rpm. The extruder zone temperature was zone 1 330/350/390 and 400 F for 1/2/3 and die bands. Film thickness is 2 mil at blow-up ratio (BUR) of 2.1: 1 and nip line speed of about 7 feet / minute (fpm) It was.

The high temperature adhesive strength and seal strength of the blown film were measured. High temperature tack or hot seal strength was measured based on ASTM F 1921, Method B. The term "high temperature tack" is used as an expression for heat seal strength immediately after sealing operation before sealing cooling to ambient temperature. The residence time was 0.5 seconds at the preset temperature and the cooling time was 0.1 seconds.

The term "sealing strength" is the strength of the heat seal after cooling to ambient temperature. Heat seal strength was measured based on ASTM Standard Test Method E88, STM for Seal Strength of Flexible Barrier Materials. The test result is a measure of the force required to separate the heat seal, or the force required to break the film when the film is broken before the heat seal portion.

The result provides heat seal strength in terms of sealing temperature. Data is aggregated in Table A.

Hot adhesive strength versus hot adhesive sealing temperature is shown in Table B.

Of the present invention Example  3-multilayer Coextruded  film

The ethylene-octene multiblock interpolymers used in Example 3 below, March 2005, each claiming priority to US Provisional Application No. 60 / 553,906, filed March 17, 2004, incorporated herein by reference. Prepared as described in PCT Application No. PCT / US2005 / 008917, filed on May 17. A comparative example is a random ethylene-octene copolymer made using a restrained geometry catalyst such as sold under the tradename Affinity® by Dow Chemical Company. The polymer has a melt index of about 1 g / 10 minutes.

Three layer coextruded films of olefin block copolymers (OBC) and those of comparative examples were prepared using conventional coextrusion techniques. The coextruded film has three layers, a backing layer, a bonding layer and a sealant layer. An embodiment of the present invention is compared with a reference film having the backing layer and the bonding layer but different from the sealant layer composition. Specifically, the backing layer consisting of 100% Capron CA95QP (available from BASF Corporation) is 1 mil thick. Dowrex 2045G (LLDPE) (sold by Dow Chemical Company) 85% and AMPLIFY GR205 (maleic anhydride modified polyethylene, HDPE-g-MAH) (sold by Dow Chemical Company) The bonding layer consisting of 15% has a thickness of 1 mil. The sealant layer contains 5% Ampacet 100329 and 2.5% Ampacet 100432, with the remainder being OBC or Affinity®. The film includes a 1.5 mil sealant layer / 1.0 mil bond layer / 1.0 mil backing layer.

High temperature adhesive strength and heat seal strength were measured in a similar manner as described in Examples 1 and 2 above. The results are shown below.

Comparison of High Temperature Adhesion Properties of 3-Layer Coextruded Films:

Comparison of heat seal data of a three-layer coextruded film with a sealant layer / bonding layer / backing layer of 1.5 / 1.0 / 1.0 mil layer thickness:

Examples of the present invention showed lower hot tack initiation temperatures, and similar or higher hot tack strengths compared to the baseline. Similarly, the examples of the present invention exhibited lower heat seal initiation temperatures and higher heat seal strengths compared to the baseline.

Although the present invention has been described with respect to a limited number of embodiments, certain features of one embodiment should not be applied to other embodiments of the invention as well. There is no single embodiment that is representative of all aspects of the invention. In some embodiments, a composition or method may comprise many compounds or steps not mentioned herein. In other embodiments, the compositions or methods do not comprise or substantially comprise any compound or step not listed herein. There are variations and modifications from the described embodiments. Finally, any numerical value disclosed herein should be intended to mean an approximation, regardless of whether the term “about” or “approximately” is used in describing the numerical value. It is intended that the appended claims cover all such modifications and variations as fall within the scope of the present invention.

Claims (21)

At least one ethylene / α-olefin interpolymer, wherein the ethylene / α-olefin interpolymer is (a) M _w / M _n is from about 1.7 to about 3.5 and has at least one melting point (T _m ) (degrees C) and density (d) (g / cm ³ ), where the values of T _m and d are Corresponds to a relation such as: T _m > -2002.9 + 4538.5 (d)-2422.2 (d) ² ; or (b) the delta amount ΔT (degrees C) defined as the heat of fusion ΔH (J / g) and the temperature difference between the maximum DSC peak and the highest CRYSTAF peak, with M _w / M _n of about 1.7 to about 3.5; Wherein the numerical values of ΔT and ΔH have the following relationship: ΔT> -0.1299 (ΔH) + 62.81 (When ΔH is greater than 0 and less than 130 J / g) ΔT is ≥ 48 ° C (when ΔH is greater than 130 J / g) Where the CRYSTAF peak is measured using at least 5% of the cumulative polymer and the CRYSTAF temperature is 30 ° C. if less than 5% of the polymer has an identifiable CRYSTAF peak; or (c) is characterized by a 300% strain and an elastic recovery rate (Re) (%) measured in a compression molded film of an ethylene / α-olefin interpolymer and have a density (d) (g / cm ³ ) Wherein the values of Re and d satisfy the following relationship when the ethylene / α-olefin interpolymers are substantially free of crosslinked phases: Re> 1481-1629 (d); or (d) having a molecular fraction eluting at 40 ° C. to 130 ° C. when fractionated using TREF, the fraction being at least 5% higher than the mole comonomer content of the comparative random ethylene interpolymer fraction eluting at the same temperature range Having a molar content, wherein the comparative random ethylene interpolymer has the same comonomer (s) as the ethylene / α-olefin interpolymer and has a melt index, density and co-polymerization within 10% of the ethylene / α-olefin interpolymer Monomer molar content (based on total polymer)); or (e) having a storage modulus at 25 ° C. G ′ (25 ° C.) and a storage modulus at 100 ° C. G ′ (100 ° C.), wherein the ratio of G ′ (25 ° C.) to G ′ (100 ° C.) A composition exhibiting high high temperature tack, ranging from about 1: 1 to about 9: 1. At least one ethylene / α-olefin interpolymer, wherein the ethylene / α-olefin interpolymer has a density from about 0.89 g / cc to about 0.94 g / cc, (a) M _w / M _n is from about 1.7 to about 3.5 and has at least one melting point (T _m ) (degrees C) and density (d) (g / cm ³ ), where the values of T _m and d are Corresponds to a relation such as: T _m > -2002.9 + 4538.5 (d)-2422.2 (d) ² ; or (b) the delta amount ΔT (degrees C) defined as the heat of fusion ΔH (J / g) and the temperature difference between the maximum DSC peak and the highest CRYSTAF peak, with M _w / M _n of about 1.7 to about 3.5; Wherein the numerical values of ΔT and ΔH have the following relationship: ΔT> -0.1299 (ΔH) + 62.81 (When ΔH is greater than 0 and less than 130 J / g) ΔT is ≥ 48 ° C (when ΔH is greater than 130 J / g) Where the CRYSTAF peak is measured using at least 5% of the cumulative polymer and the CRYSTAF temperature is 30 ° C. if less than 5% of the polymer has an identifiable CRYSTAF peak; or (c) characterized by a 300% strain and an elastic recovery rate (Re) (%) measured in a compression molded film of an ethylene / α-olefin interpolymer and have a density (d) (g / cm ³ ) Wherein the values of Re and d satisfy the following relationship when the ethylene / α-olefin interpolymers are substantially free of crosslinked phases: Re> 1481-1629 (d); or (d) having a molecular fraction eluting at 40 ° C. to 130 ° C. when fractionated using TREF, the fraction being at least 5% higher than the mole comonomer content of the comparative random ethylene interpolymer fraction eluting at the same temperature range Having a molar content, wherein the comparative random ethylene interpolymer has the same comonomer (s) as the ethylene / α-olefin interpolymer and has a melt index, density and within 10% of the ethylene / α-olefin interpolymer Having a comonomer molar content (based on the entire polymer); or (e) having a storage modulus at 25 ° C. G ′ (25 ° C.) and a storage modulus at 100 ° C. G ′ (100 ° C.), wherein the ratio of G ′ (25 ° C.) to G ′ (100 ° C.) Wherein the heat-sealable film layer composition ranges from about 1: 1 to about 9: 1. The heat-sealable film layer composition of claim 2, wherein the density is from about 0.900 g / cc to about 0.925 g / cc. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the melt index (I ₂ ) is from about 0.5 g / 10 minutes to about 3 g / 10 minutes. 4. The heat-sealable film layer composition of claim 2 or 3, which is suitable for a blown film layer. 4. The heat-sealable film layer composition of claim 2 or 3, suitable for a blown film layer having a thickness of about 1 to about 3 mils. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the ethylene / α-olefin interpolymer is an ethylene-octene copolymer. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the ethylene / α-olefin interpolymer is an ethylene-butene copolymer. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the ethylene / α-olefin interpolymer is an ethylene-hexene copolymer. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the extreme high temperature tack is greater than about 2 N / in based on ASTM F 1921, Method B. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the 2 mil monolayer film of the composition has a high temperature tack greater than about 1 N / in over a temperature range of at least about 20 ° C. 4. The heat-sealable film layer composition of claim 2 or 3, wherein the 2 mil monolayer film of the composition has a high temperature tack greater than 1 N / in over a temperature range of about 40 ° C. or greater. A multilayer film structure made from the heat-sealable film layer composition of claim 2. The process of claim 1 wherein polyethylene, polypropylene, polyvinyl chloride, ethylene-propylene copolymers, ethylene-co-vinyl acetate, terpolymers of ethylene and propylene and nonconjugated dienes, mixed polymers of ethylene and vinyl acetate, styrene -Butadiene mixed polymers, and combinations thereof, wherein the composition further comprises one or more other different polymers selected from the group consisting of. The composition of claim 1 which is a coextruded film comprising a sealant layer, a backing layer and a bonding layer. At least one ethylene / α-olefin interpolymer, wherein the ethylene / α-olefin interpolymer has a density of about 0.89 g / cc to about 0.94 g / cc and a molecular weight distribution (M _w / M _n ) of about Greater than 1.3, (a) a molecular fraction eluting at 40 ° C. to 130 ° C. when fractionated using TREF, characterized in that the block index is from 0.5 to about 1; or (b) an average block index greater than 0 and up to about 1.0 A heat-sealable film layer composition, characterized in that. The heat-sealable film layer composition of claim 16, wherein the density is from about 0.900 g / cc to about 0.925 g / cc. 18. The heat-sealable film layer composition of claim 16 or 17, wherein the melt index (I ₂ ) is from about 0.5 g / 10 minutes to about 3 g / 10 minutes. 18. The heat-sealable film layer composition of claim 16 or 17, wherein the extreme high temperature tack is greater than about 2 N / in based on ASTM F 1921, Method B. 18. The heat-sealable film layer composition of claim 16 or 17, wherein the 2 mil monolayer film of the composition has a high temperature tack greater than about 1 N / in over a temperature range of at least about 20 ° C. 18. The heat-sealable film layer composition of claim 16 or 17, wherein the 2 mil monolayer film of the composition has a high temperature tack greater than 1 N / in over a temperature range of at least about 40 ° C.

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