MXPA99002105A - Compositions comprising a substantially random interpolymer of at least one alpha-olefin and at least one vinylidene aromatic monomer or hindered aliphatic vinylidene monomer - Google Patents

Abstract

Disclosed are compositions comprising at least one substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer and optionally at least one C3-C20&agr;-olefin monomer, and at least one tackifier. The claimed compositions are useful in adhesives, such as are employed in various applications, such as in packaging and carton sealing, bookbinding, masking tape, clear office tape, labels, decals, bandages, decorative and protective sheets (such as shelf and drawer liners), floor tiles, sanitary napkin/incontinence device placement strips, sun control films, and the joining of gaskets to automobile windows. The claimed compositions further find use in a variety of applications, such as sealants, coatings, molded articles, and multilayered structures.

Description

COMPOSITIONS THAT COMPRISE 1 JN INTERPOLIMERO SUBSTANTIALLY RANDOM OF AT LEAST ONE ALPHA-OLEFINE AND WHEN LESS AN AROMATIC MONOMER OF VINYLIDENE OR A MONOMER OF IMPAIRED ALIPHATIC VINYLIDENE The present invention relates to compositions based on olefin. In particular, the present invention relates to compositions comprising at least one substantially random interpolymer of at least one α-olefin and an aromatic vinylidene monomer or a monomer, of hindered aliphatic vinylidene, preferably at least one substantially random interpolymer of ethylene, optionally at least one α-olefin and one aromatic vinylidene monomer, in conjunction with at least one adhesive, wax, or processing aid. Substantially random interpolymers of at least one α-olefin and an aromatic vinylidene monomer or a hindered aliphatic vinylidene monomer are known in the art, including materials such as α-olefin / vinyl aromatic monomer interpolymers, and offer a range of structures and material properties that make them useful for different applications, such as compatibilizers for blends of polyethylene and polystyrene as described in U.S. Patent Number 5,460,818.

A particular aspect described by D'Anniello et al. (Journal of Applied Polymer Science, volume 58, pages 1701-1706 [19951]) is that such interpolymers can show good elastic properties and energy dissipation characteristics. In another aspect, the selected interpolymers may find utility in adhesive systems, as illustrated in U.S. Patent Number 5,244,996, issued to Mitsui Petrochemical Industries Ltd. Although they are useful in their own right, the industry seeks to improve applicability of these substantially random interpolymers. For example, it may be desirable in certain cases to manipulate the glass transition temperature of the substantially random interpolymer, and thereby allow materials based on substantially random interpolymers to find application in, for example, molded articles and as sealants and adhesives. The glass transition temperature of a polymer is one of the main physical parameters that determines its mechanical properties. Below the transition temperature, polymers are commonly rigid plastics that carry a stiff load. Above the transition temperature to the glass, the materials exhibit a more rubbery behavior. When the transition temperature to the glass is in the range of the ambient temperature, the properties observed for the polymer can change depending on the environmental conditions. It is therefore advantageous to be able to control the glass transition temperature of a polymer to achieve the desired property profile. For example, in the case of substantially random interpolymers which have a glass transition temperature of about -25 to about 25 ° C, it would be desirable in certain cases to raise the glass transition temperature. For example, substantially random interpolymers having a glass transition temperature of about room temperature are susceptible to deleterious blocking. Furthermore, when the glass transition temperature is about room temperature, the product properties will vary, depending on the actual temperature, which leads to an undesired product variation. In addition, when the glass transition temperature is at room temperature, it optimizes the use in certain applications, such as in pressure sensitive adhesives, if desired. One way to control the glass transition temperature of a copolymer is to change the type of comonomer and the amount thereof in the copolymer. For example, this approach is used to control the glass transition temperature of acrylic copolymers. An alternative for varying the content of the comonomer is to add another material having a different glass transition temperature to a base material. However, it is known that the addition of a brittle low molecular weight diluent, although it may increase the glass transition temperature, will typically lead to a degradation in mechanical properties, such as tensile strength. It was expected that the addition of the class of materials commonly described as adhesion enhancers to substantially random interpolymers, particularly those inerpolymers that are elastomeric, would dilute the network of the polymer and lead to tensile properties, that is, tensile strength in the breaking and stretching at break, which are less than the substantially random interpolymer alone. There is a need to provide compositions comprising substantially random interpolymers of at least one α-olefin and at least one aromatic or hindered vinylidene aliphatic monomer, which have a glass transition temperature over substantially random unmodified interpolymers, particularly those that have a glass transition temperature higher than the ambient temperature. There is a need for such a composition which is obtained without a corresponding loss in tensile properties. There is a need to provide improved hot melt adhesive formulations comprising substantially random interpolymers of at least one α-olefin and at least one aromatic or hindered aliphatic monomer which harmonizes the superior performance characteristics with the unmodified polymers, which It will further expand the usefulness of this interesting class of materials. Hot melt adhesives generally comprise three components: a polymer, an adhesive improver, and a wax. Each component may comprise a mixture of two or more components, that is, the polymer component may comprise a mixture of two different polymers. The polymer provides cohesive strength to the adhesive bond. The adhesiveness improver provides adhesiveness to the adhesive which serves to secure the articles to be joined while the adhesive is seated, and reduces the viscosity of the system making it easier to apply the adhesive to the substrate. The adhesiveness improver can be further used to control the glass transition temperature of the formulation. The wax shortens the opening / closing times and reduces the viscosity of the system. Hot melt adhesives can typically additionally comprise oil as a filler and / or to reduce the viscosity of the system. Hot melt adhesives based on polymers previously used include copolymers of ethylene vinyl acetate (EVA), atactic polypropylene (APP), amorphous polyolefins, low density polyethylene (LDPE), and homogeneous linear ethylene / α-olefin copolymers. Hot melt adhesives of the prior art typically employed high levels of adhesiveness improver to reduce the viscosity of the system to levels that enabled its easy application to the substrate, for example, at viscosities less than about 5000 centipoise. Pressure sensitive adhesives are materials that are aggressively and permanently adhesive at room temperature at the time of application, and which adhere firmly to a variety of uneven surfaces with the application of light pressure, such as pressure with a finger. Despite their aggressive adhesiveness, pressure sensitive adhesives can be removed from smooth surfaces without leaving a significant residue. Pressure sensitive adhesives are widely used in everyday applications, such as adhesive tape, transparent office tape, labels, decals, bandages, decorative and protective sheets (such as shelf and drawer coverings), floor tiles, strips for the placement of incontinence device / sanitary pad, control films solar, and the union of packaging to automobile windows. Historically, pressure sensitive adhesives were based on natural rubber and wood rosins, which were carried by a solvent. The articles bearing said adhesives were manufactured by applying the adhesive on a suitable support, and the solvent was removed by a devolatilization process. However, in response to increases in solvent costs and regulatory restrictions with reference to emissions, water-based adhesives and hot melt adhesives (HMAs) have been developed solidly.

Historically, adhesives have been based on one of four types of polymers: elastomers (such as natural rubber, striene-isoprene-styrene block copolymers, styrene-butadiene-styrene block copolymers, and styrene-butadiene random copolymers); acrylics (such as interpolymers or butyl acrylate, 2-ethylhexyl acrylate, and methyl methacrylate); hydrocarbons (such as atactic polypropylene, amorphous polypropylene, poly i-1-butene, and low density polyethylene) and ethylene vinyl acetate. More recently, hot melt adhesives based on homogeneous linear and substantially linear ethylene polymers have been described and claimed. Diene-based elastomers can be used in solvent-based, water-based, and hot-melt adhesives. However, adhesive systems based on such elastomers are disadvantageous because the unsaturation sites in the block copolymer support render the hot melt adhesives susceptible to degradation, by the action of oxygen and ultraviolet light. Acrylic systems, although stable to oxygen and ultraviolet light, are inferior to diene-based elastomer systems in terms of the balance of adhesiveness, peel strength, and slip which is preferred for adhesive applications sensitive to Pressure. In addition, such systems are typically available only in solvent-based and water-based systems, making them more disadvantageous for the reasons stated above. The hydrocarbon-based systems were developed at least in part to provide improved stability to oxygen and ultraviolet light, as compared with the diene-based elastomer systems, as well as the ability to be used in the adhesive systems. Hot melt. The systems based on hydrocarbons which comprise, atactic polypropylene, interpolymers of propylene with higher α-olefins, or poly-α-olefins, said systems exhibit a poor balance of properties. In particular, poly-1-butene has a tendency to crystallize slowly after application to the substrate, leading to a profound loss of adhesiveness. When oil is added to increase the adhesiveness, the oil tends to migrate outward from the adhesive into the backing layer or substrate. The atactic polypropylene and the poly-α-olefins suffer from a low tensile force, which leads to a low cohesive force in the detachment and to leave a residue on the surface of the substrate after detachment. Hydrocarbon based systems are typically not preferred due to the limited capacity of low density polyethylene to accept the formulation ingredients required to produce a hot melt adhesive with adequate mechanical properties. Systems based on ethylene vinyl acetate are limited because as higher vinyl acetate levels are selected, elastic performance increases, but compatibility with the ingredients of the formulation decreases. US Patent No. 5,530,054 discloses hot melt adhesives based on homogeneous linear ethylene / α-olefin copolymers. The present invention relates to a composition comprising at least one substantially random ethylene interpolymer and an aromatic vinylidene comonomer or a hindered aliphatic vinylidene comonomer and optionally at least one third comonomer selected from the group consisting of 3-α-olefins. 20 carbon atoms, and at least one adhesive enhancer. The present invention further relates to a composition comprising at least one substantially random ethylene interpolymer and an aromatic vinylidene comonomer or a hindered aliphatic vinylidene comonomer and optionally at least one third comonomer selected from the group consisting of 3-α-olefins. at 20 carbon atoms, and at least one adhesiveness improver, and at least one extensor composition or modifier or processing aid. The present invention further relates to such a composition, which additionally comprises an extender or modifier composition selected from the group consisting of the following: paraffin waxes, crystalline polyethylene waxes, styrene block copolymers, ethylene vinyl acetate, polymers or interpolymers of styrene and / or styrene substituted by alkyl, such as a-methyl styrene, and homogeneous linear or substantially linear ethylene interpolymers and one or more α-olefins of 3 to 20 carbon atoms. The present invention further relates to said composition in the form of an adhesive, a layer of a multilayer food packaging structure, a coating, a sealant, a molded article, or a sound attenuating device. Unless otherwise indicated, the following test procedures shall be employed: Density is measured in accordance with ASTM D-792. The samples harden at room temperature for 24 hours before taking the measurement. The melt index (I2) is measured in accordance with the ASTM D-1238, condition of 190 ° C / 2.16 kilograms (formally known as "Condition (E)"). The molecular weight is determined using gel permeation chromatography (GPC) on a high temperature chromatographic unit at 150 ° C of Waters equipped with three columns of mixed porosity (Polymer Laboratories 103, 104, 105 and 106), operating at a temperature of 140 ° C system. The solvent is 1,2,4-trichlorobenzene, of which 0.3 percent by weight solutions of the samples are prepared by injection. The flow rate is 1.0 milliliters / minute and the injection size is 100 microliters. Molecular weight determination is deduced by the use of reduced molecular weight distribution polystyrene standards (from Polymer Laboratories) in conjunction with their leach volumes. The equivalent molecular weights of polystyrene are determined by using the appropriate Mark-Houwink coefficients for polyethylene and polystyrene (as described by Williams and Word in the Journal of Polymer Science, Polymer Letters, volume 6, (621) 1968, incorporated in the present one as a reference) to derive the following equation: "polyethylene = a * (Mpolystyrene) b In this equation, a = 0.4316 and b = 1.0. The weight average molecular weight, Mw9, is calculated in the usual manner according to the following formula: Mw =? w¡ * M¡, where w¡ Y M i are the fraction by weight and the molecular weight, respectively, of the fraction and leaching from the column of gel permeation chromatography. The melt viscosity is determined according to the following procedure using a DVII + Brookfield Viscometer Laboratories in disposable aluminum sample chambers. The spindle used is a SC-31 hot melt spindle, suitable for measuring viscosities in the range of 10 to 100,000 centipoise. A cutting blade is used to cut samples into pieces small enough to fit within the sample chamber of 2.54 centimeters in width, and 12.7 centimeters in length. The sample is placed in the chamber, which in turn is inserted into a Brookfield Thermosel and closed in place with bent ear pincers. The sample chamber has a notch in the bottom that adjusts the bottom of the Brookfield Thermosel to ensure that the camera will not flip when the spindle is inserted and when it is spinning. The sample is heated to 190.88 ° C, with the additional sample being added until the fused sample is approximately 2.54 centimeters below the top of the sample chamber. The viscometer apparatus is lowered and the spindle is immersed inside the sample chamber. Continue lowering until the brackets on the viscometer are aligned on the Thermosel. The viscometer is turned over, and placed at a shear rate index which leads to a torsional moment reading in the range of 30 to 60 percent. The readings are taken every minute for approximately 15 minutes, or until the values stabilize, the final reading of which is recorded. The G ', G "and tan delta peak are determined as follows, the samples are examined using fusion rheology techniques on a Rheomterics RDA-II Dynamic Analyzer, using the Temperature-Step mode using the parallel plate geometry of 7.9. millimeters in diameter.The stork is run from approximately -70 ° C to 250 ° C at 5 ° C per step with 30 seconds of equilibrium delay in each step.The oscillatory frequency is 1 radian / second with a self-traction function of 0.1 percent of traction initially, increasing in positive 100 percent settings as long as the torsional moment decreases to 10 grams-centimeters Plates with an initial space of 1.5 millimeters at 160 ° C are used. nitrogen through all analyzes to minimize oxidative degradation A G 'diagram is drawn (the dynamic storage module of the sample), G "(the dynamic sample loss module), the delta tanning (G7G") and the delta peak tanning (a representation of the glass transition temperature.) The glass transition temperature (DSC) is determined using calorimetry. of differential scanning, with a scanning index of 10 ° C / minute from -75 to 150 ° C. The adhesiveness of the probe is determined using a Viscosity Probe of Poliken Digital Probe TMI-80-02-01 (available with Testing Machines, Inc., (New York) in accordance with ASTM-D2979-71 The term "interpolymer" is used herein to mean a copolymer, or a terpolymer, or the like, that is, polymerize at least one other comonomer with ethylene to make the interpolymer The term "hydrocarbyl" means any aromatic groups substituted aliphatic, cycloaliphatic, aromatic, aliphatic substituted by aryl, cycloaliphatic substituted by aryl, aliphatic substituted aromatic, or The aliphatic or cycloaliphatic groups are preferably saturated. Similarly, the term "hydrocarbyloxy" means a hydrocarbyl group having an oxygen bond between it and the carbon atom to which it is attached. The term "randomly randomized" in the substantially random interpolymer comprising an α-olefin and an aromatic vinylidene monomer or a hindered aliphatic vinylidene monomer as used herein means that the distribution of the monomers of said interpolymer can be described by the statistical model of Bernoulli or by means of a statistical model of Markovian of first or second order, as described by JC Randall in Polvmer Sequence Determination, Carbon-13 NMR Method, Academic Press New York, 1977, pages 71-78. Preferably, the substantially random interpolymer comprising an α-olefin and a vinylidene aromatic monomer does not contain more than 15 percent of the total amount of aromatic vinylidene monomer in aromatic vinylidene monomer blocks of more than 3 units. More preferably, the interpolymer is not characterized by a high degree of either isotacticity or syndiotacticity. This means that in the 13C-NMR spectrum of the substantially random interpolymer the peak areas corresponding to the methylene and methine master chain carbons representing either meso-dyadic sequences or racemic dyadic sequences should not exceed 75 percent of the total area peak of the methylene and methine carbons of the main chain. Any numeric values named herein include all values from the lowest value to the highest value in increments of one unit as long as there is a separation of at least 2 units between any lower value and any higher value. As an example, if it is stated that the amount of a component or a value of a process variable such as, for example, temperature, pressure, time and the like is, for example, from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, it is intended that values such as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc., be expressly listed in this specification. For values that are less than one, a unit is considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate. These are just some examples of what is specifically intended and it should be considered that all possible combinations of numerical values between the lowest value and the highest value should be expressly set forth in this application in a similar manner. Interpolymers suitable for use as, or as components in, the compositions of the invention, include, but are not limited to, interpolymers prepared by the polymerization of ethylene, one or more vinylidene aromatic monomers and / or one or more vinylidene monomers. hindered aliphatics, and optionally at least a third conmonomer selected from the group consisting of α-olefins of 3 to 20 carbon atoms. Suitable α-olefins include for example, those containing up to about 20, up to about 12, most preferably up to about 8 carbon atoms. Propylene, butene-1,4-methyl-1-pentene, hexene-1 and octene-1 are particularly suitable. Other suitable α-olefin monomers include norbornenes. Suitable vinylidene aromatic monomers include, for example, those represented by the following formula: wherein R1 is selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to about 4 carbon atoms, preferably hydrogen or methyl; each R2 is independently selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to about 4 carbon atoms, preferably hydrogen or methyl; Ar is a phenyl group or a phenyl group substituted with from 1 to 5 substituents selected from the group consisting of halogen, alkyl of 1 to 4 carbon atoms, and haloalkyl of 1 to 4 carbon atoms; and n is a value from zero to about 6, preferably from zero to about 2, more preferably zero. Exemplary monovinylidene aromatic monomers include styrene, vinyltoluene, α-methylstyrene, t-butylstyrene, chlorostyrene, including all isomers of these compounds. Such particularly suitable monomers include styrene and lower alkyl or halogen-substituted derivatives thereof. Preferred monomers include styrene, α-methylstyrene, lower alkyl or substituted phenyl ring derivatives of styrene, para-vinyltoluene, or mixtures thereof, and the like. A most preferred monovinylidene aromatic monomer is styrene. The term "hindered aliphatic or cycloaliphatic vinylidene monomers" means addition polymerizable vinylidene monomers corresponding to the following formula: C = C (R2) 2 wherein A1 is an aliphatic, sterically heavy substituent of up to 20 carbons, R1 is selected from the group of radicals consisting of hydrogen and alkyl radicals containing from 1 to about 4 carbon atoms, preferably hydrogen or methyl; each R2 is independently selected from the group of radicals consisting of hydrogen and alkyl containing from 1 to about 4 carbon atoms, preferably hydrogen or methyl; or alternatively R1 and A1 together form a ring system. By the term "sterically heavy" is meant that the monomer bearing this substituent is normally incapable of addition polymerization by standard Ziegler-Natta polymerization catalysts at an index comparable with ethylene polymerizations. Preferred aliphatic or vinylidene cycloaliphatic monomers are those in which one of the carbon atoms bearing ethylenic unsaturation is tertiary or substituted quaternary. Examples of such substituents include cyclic aliphatic groups such as cyclohexyl, cyclohexenyl, cyclooctenyl, or substituted alkyl or aryl ring derivatives of the mimes, tert-butyl, norbornyl. The most preferred hindered aliphatic vinylidene compounds are the various isomeric vinyl ring substituted derivatives of cyclohexene and substituted cyclohexenes, and 5-ethylidene-2-norbornene. Particularly suitable are 1-, 3-, and 4-vinylcyclohexene. The interpolymers of one or more α-olefins and one or more monovinylidene aromatic monomers and / or one or more hindered aliphatic or cycloaliphatic vinylidene monomers employed in the present invention are substantially random polymers. These interpolymers contain from about 1 to about 65 mole percent of at least one aromatic vinylidene monomer and / or hindered or aliphatic vinylidene monomer or cycloaliphatic monomer and from about 35 to about 99 mole percent ethylene. When the substantially random interpolymer has from 1 to less than 5 mole percent of the at least one aromatic vinylidene monomer and / or the hindered or aliphatic vinylidene monomer or cycloaliphatic monomer, the substantially random interpolymer will impart a crystalline character to the adhesive system. When the substantially random interpolymer has from 5 to less than 25 mole percent of the at least one aromatic vinylidene monomer and / or the hindered or aliphatic vinylidene monomer or cycloaliphatic, the substantially random interpolymer will impart an elastomeric character to the adhesive system. When the substantially random interpolymer has from 25 to 50 mole percent of the at least one vinylidene aromatic monomer and / or the hindered aliphatic or cycloaliphatic vinylidene monomer, the substantially random interpolymer will impart an amorphous character to the adhesive system. When the substantially random interpolymer is used as the strength imparting component of an adhesive, the number average molecular weight (Mn) of these interpolymers is usually greater than about 1,000, preferably from about 5,000 to about 1,000,000, more preferably about 10,000 to about 500,000, and most preferably from about 50,000 to about 300,000. As described below, the ultra low molecular weight ethylene polymers, a class of which include ultra low molecular weight ethylene interpolymers and at least one aromatic vinylidene monomer and / or a hindered or cycloaliphatic vinylidene monomer, they can be suitably employed in the practice of this invention, if not as the component that imparts strength to the formulation, then as tackifiers or modifiers. While the substantially random interpolymers are being prepared, as will be described hereinafter, an aromatic vinylidene homopolymer amount can be formed due to the homopolymerization of the vinylidene aromatic monomer at elevated temperatures. In general, the higher the polymerization temperature, the higher the amount of homopolymer formed. The presence of the aromatic vinylidene homopolymer is not generally detrimental to the purposes of the present invention and can be tolerated. The aromatic vinylidene homopolymer can be separated from the interpolymer, if desired, by extraction techniques such as selective precipitation from the solution with a non-solvent for and either the interpolymer or the aromatic vinylidene homopolymer. For the purpose of the present invention, it is preferred that no more than 20 weight percent, preferably less than 15 weight percent, most preferably less than 10 weight percent, based on the total weight of the interpolymers be present. of the aromatic vinylidene homopolymer.

Substantially random interpolymers can be modified by insertion, hydrogenation, functionalization, or other typical reactions well known to those skilled in the art. The polymers can be easily sulfonated or chlorinated to provide functionalized derivatives in accordance with established techniques. The substantially random interpolymers are prepared by polymerizing a mixture of polymerizable monomers in the presence of metallocene or catalysts of restricted geometry. Substantially random interpolymers can be prepared as described in U.S. Patent Application Serial Number 545,403 filed July 3, 1990 (corresponding to EP-AO, 416, 815) by James C. Stevens and collaborators. The preferred operating conditions for such polymerization reactions are pressures from atmospheric to 3000 atmospheres (300 MPa) and temperatures from -30 ° C to 200 ° C. In EP-A-416,815; EP-A-514,828; EP-A-520,732; Application of the United States of America Serial Number 241,523, filed May 12, 1994; as well as in the Patents of the United States of North America Nos. 5,055,438; 5,057,475; 5,096,867; 5,064,802; 5,132,380; 5,189,192; 5,321,106; 5,347,024; 5,350,723; 5,374,696; and 5,399,635, examples of suitable catalysts and methods for preparing substantially random interpolymers are described. The substantially random aromatic interpolymers of α-olefin / vinylidene can also be prepared by the methods described by John G. Bradfute et al. (W.R. Grace &Co.) in WO 95/32095; by R.B. Pannel (Exxon Chemical Patents, Inc.) in WO 94/00500; and in Plastics Technology, page 25 (September 1992). The substantially random aromatic interpolymers of α-olefin / vinylidene can also be prepared by the methods described in JP 07/278230 using the compounds shown by the general formula Cp1 R \ Z i M \ Cpz R¿ wherein (Cp1 and Cp2 are cyclopentadienyl groups, indenyl groups, fluorenyl groups, or substituents thereof, independently of one another; R1 and R2 are hydrogen atoms, halogen atoms, hydrocarbon groups with carbon numbers of 1-12, groups alkoxy, or aryloxy groups, independently of one another, M is a group of IV, preferably Zr or Hf, more preferably Zr, and R3 is an alkylene group or a group, sila nediilo used to crosslink Cp1 and Cp2) . Also suitable are substantially random interpolymers possessing at least one tetradiádica of α-olefin / aromatic vinyl / aromatic vinyl / α-olefin. These interpolymers contain additional signals with intensities greater than three times the peak-to-peak noise. These signals appear in the chemical substitution range of 43.75-44.25 ppm and 38.0-38.5 ppm. Specifically, peaks greater than 44.1, 43.9 and 38.2 ppm are observed. An NMR proton test experiment indicates that the signals in the chemical substitution region 43.75-44.25 ppm are methine carbons and the signals in the 38.0-38.5 ppm region are methylene carbons. In order to determine the carbon-13NMR chemical substitutions of these interpolymers, the following procedures and conditions are employed. A polymer solution of five to ten percent by weight in a mixture consisting of 50 volume percent of 1,1,1,2-tetrachloroethane-d 2 and 50 volume percent chromium tris (acetylacetonate) is prepared. of 0.10 molar in 1, 2,4-trichlorobenzene. The NMR spectra are obtained at 130 ° C using a reverse sequence of valve-regulated decoupling, a pulse amplitude of 90 ° and a pulse delay of five seconds or more. The spectra are referenced to the methylene signal isolated from the polymer assigned at 30,000 ppm. It is believed that these new signals are due to sequences involving two aromatic vinyl monomers from head to tail preceded and followed by at least one α-olefin insert., that is to say an a-olefin / aromatic vinyl / aromatic vinyl / α-olefin tetradiádica in which the insertions of styrene monomer of said tetradiádicas occur exclusively in a 1, 2 (head to tail) manner. One skilled in the art understands that for such tetradiáds involving a non-styrene vinyl aromatic monomer and an α-olefin non-styrene monomer ethylene, the a-olefin / aromatic vinyl / aromatic tetradiádica of vinyl / α-olefin will give rise to similar carbon-13 NMR peaks but with slightly different chemical substitutions. These interpolymers are prepared by conducting the polymerization at temperatures of from about -30 ° C to about 250 ° C in the presence of such catalysts as those represented by the formula: Cp / \ (ER2) n¡ MR'2 \ / CP wherein: each Cp is independently, each occurrence, a group of substituted cyclopentadienyl linked at p with M; E is C or So; M is a group of metal IV, preferably Zr or Hf, more preferably Zr; each R is independently, each occurrence, H, hydrocarbyl, silahydrocarbyl, oh id rock R i is i, which contains up to about 30, preferably from 1 to about 20, most preferably from 1 to about 10 carbon atoms or silicone, each R2 'is independently, each occurrence, H, halogen, hydrocarbyl, hydrocarbyloxy, silahydrocarbyl, hydrocarbylsilyl containing up to about 30, preferably from 1 to about 20, most preferably from 1 to about 10 carbon atoms. carbon or silicone or two groups of R 'together may be 1, 3-butadiene substituted by hydrocarbyl of 1 to 10 carbon atoms; m is 1 or 2; and optionally, but preferably in the presence of an activating cocatalyst. Particularly, substituted cyclopentadienyl groups include those that are illustrated by the formula: wherein each R is independently, each occurrence, H, hydrocarbyl, silahydrocarbyl, or -hydrocarbylsilyl, containing up to about 30, preferably from 1 to about 20, more preferably from 1 to about 10 carbon or silicone atoms or two R groups together form a divalent derivative of said group. Preferably, R independently, each occurrence, is (including where all isomers are appropriate) hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl, phenyl, or silyl or (where appropriate) two R groups they are joined together to form a ring system such as indenyl, fluorenyl, tetrahydroindenyl, tetrahydrofluorenyl, or octahydrofluorenyl. Particularly preferred catalysts include, for example, the racemic dichloride of (dimethylsilanediyl (2-methyl-4'-phenylindene) zirconium, 1,4-dif in racemic il-1,3-butadiene of (dimethylsilanediyl (2-methyl-4) -phenylindenyl)) zirconium, racemic di-alkyl of (dimethylsilanediyl (2-methyl-4-phenylindenyl) zirconium of 1 to 4 carbon atoms, racemic di-alkoxide of (dimethylsilanediyl (2-methyl-4-phenylindenyl)) zirconium 1 to 4 carbon atoms, or any combination thereof and the like Additional methods of preparation for the substantially random interpolymer have been described in the literature, Longo and Grassi (Makromol, Chem., Volume 191, pages 2387 to 2396 [1990]. ] and D'Anniello et al. (Journal of Applied Polymer Science, volume 58, pages 1701-1706 [1995]) reported the use of a catalytic system based on methylalumoxane (MAO) and cyclopentadienyltitanium trichloride (CpTiCI3) to prepare a copolymer of ethylene-styrene, Xu and Lin (Pol vmer Preprints, Am. Chem. Soc, Div. Polvm. Chem.) Volume 35, pages 686, 687 [1994] have reported copolymerization using a TiCl4 / NdCI3 / AI (iBu) 3 catalyst to yield random copolymers of styrene and propylene. Lu et al. (Journal of Applied Polvmer Science, volume 53, pages 1453 to 1460 [1994] have described the copolymerization of ethylene and styrene using a TiCl4 / NdCI3 / MgCl2 / AI (Et) 3 catalyst. U.S. Patent No. 5,244,996, issued to Mitsui Petrochemical Industries, Ltd., describes the manufacture of olefin / vinyl aromatic monomer interpolymers such as propylene / styrene and butene / styrene.

Polymerization can be carried out in solution polymerization reactions, grout, or gas phase. In addition, polymerization can be carried out as a batch process or a continuous polymerization process. In a continuous process, the ethylene, the vinylidene aromatic monomer or the hindered aliphatic vinylidene monomer, and optionally a solvent and propylene or a third alternative monomer are continuously supplied to the reaction zone and the polymer product is continuously removed. of the same. In general, the substantially random interpolymer can be polymerized under conditions for polymerization reactions of the Ziegler-Natta or Kaminsky-Sinn type, that is, reactor pressures ranging from atmospheric to 3500 atmospheres (350 MPa). The reactor temperature will typically be from -30 ° C - 200 ° C. Preferably, the temperature of the reactor will be greater than 80 ° C, typically from 100 ° C to 200 ° C, and preferably from 100 ° C to 150 ° C, with temperatures at the highest end of the range, that is, temperatures greater than 100 ° C favoring the formation of lower molecular weight polymers. Polymerizations at temperatures above the autopolymerization temperature of the respective monomers may result in the formation of some amounts of homopolymer polymerization products resulting from the polymerization of the free radical. In the case of a slurry polymerization process, the substantially random interpolymer can use the catalysts as described above, such as supported on an inert support, such as silica. As a practical limitation, the slurry polymerization is carried out in liquid diluents in which the product of the polymer is substantially insoluble. Preferably, the diluent for the slurry polymerization is one or more hydrocarbons with less than 5 carbon atoms. If desired, saturated hydrocarbons such as ethane, propane or butane may be used in whole or in parts as the diluent. Similarly, the α-olefin monomer or a mixture of different α-olefin monomers may be used in whole or parts as the diluent. More preferably, the diluent comprises at least most of the monomer or monomers to be polymerized. The glass transition temperature of the substantially random interpolymers increases as the molar percentage of the aromatic vinylidene comonomer or the hindered aliphatic vinylidene comonomer increases. This suggests that by controlling the content of the aromatic vinylidene comonomer or the hindered aliphatic vinylidene comonomer, one can control the adhesiveness of the adhesive system. In particular, substantially random ethylene / styrene interpolymers, comprising from 1 to less than 5 mole percent styrene will have a Tg of from about -15 to -20 ° C.; substantially random ethylene / styrene interpolymers, comprising from 5 to less than 25 mole percent styrene will have a Tg of from about -15 to 0 ° C; and substantially random ethylene / styrene interpolymers of at least 25 mole percent styrene will have a Tg of about 0 to 30 ° C; with Tg being determined by differential scanning calorimetry. Accordingly, the ultra low molecular weight ethylene interpolymers and at least one aromatic vinylidene comonomer or a hindered aliphatic vinylidene comonomer can be used as an improved adhesiveness enhancing component of the adhesive system. Those skilled in the art will recognize that the incorporation of the thermonomers, such as other α-olefins, will give rise to glass transition temperatures different from those previously established. In addition or as an alternative for adjusting the styrene content of the substantially random interpolymer, when desired a composition having a glass transition temperature of at least -10 ° C, particularly when the composition is desired to maintain the elastomeric properties, it will be preferred that said composition comprises at least one substantially random interpolymer and at least one adhesiveness improver. As used herein, the term "adhesiveness improver" means any of many hydrocarbon-based compositions useful for raising the glass transition temperature of the substantially random interpolymer by at least 5 ° C and / or for imparting adhesiveness to an adhesive. hot melt which comprises the substantially random interpolymer. ASTM D-1878-61T defines adhesiveness as "the property of a material which enables it to form a union of measurable force immediately upon contact with another surface". Adhesion enhancing resins are obtained by the polymerization of petroleum and terpene feed streams and from the derivatization of wood, rubber, and wood pulp oil rosin. Different classes of tackifiers include wood rosin, wood pulp oil and wood pulp oil derivatives, cyclopentadiene derivatives, such as those described in UK Patent Application Number GB 2,032,439A. Other classes of tackifiers include aliphatic resins with 5 carbon atoms, polyterpene resins, hydrogenated resins, mixed aliphatic-aromatic resins, rosin esters, natural and synthetic terpenes, terpenphenols and hydrogenated rosin esters. Rosin is a solid material that occurs naturally in the oleoresin of pine trees and is typically derived from the oleoresin exudate of the living tree, from aged stumps and from wood pulp oils produced as a by-product of the manufacture of kraft paper. . After it is obtained, the rosin can be treated by hydrogenation, dehydrogenation, polymerization, esterification, and other post-treatment processing. Rosin is typically classified as a rubber rosin, a wood rosin, or as a rosin of wood pulp oil which indicates its source. The unmodified materials, in the form of esters or polyhydric alcohols, can be used and can be polymerized through the inherent unsaturation of the molecules. These materials are commercially available and can be mixed in adhesive compositions using standard mixing techniques. Representative examples of said rosin derivatives include pentaerythritol esters of wood pulp oil, rubber rosin, wood rosin, or mixtures thereof. Exemplary aliphatic resins include those available under the registered trademark designations Escorez MR Piccotac MR Mercures MR Wingtack MR HiRez MR QuintoneMR, TackirolMR, etcetera. Exemplary polyterpene resins include those available under the registered trademark designations Nirez ™, Piccolyte ™, Wingtack ™, ZonarezMR, etcetera. Exemplary hydrogenated resins include those available under the registered trademark designations Escorez ™, Arkon ™, Clearon ™, and the like. Exemplary mixed aromatic aliphatic resins include those available under the registered trademark designations Escorez R, Regalite ™, Hercures ™, AR R, Lmprez ™, Norsolene ™, Marukarez ™, Arkon ™, M, Quintone ™, Wingtack ™, and so on. A particularly preferred class of adhesivity improvers includes the styrene / α-methylene styrene tackifier builders available with Hercules. Other adhesion enhancers may be employed as long as they are compatible with the substantially linear ethylene / α-olefin interpolymer and the optional plasticizer. A suitable adhesiveness improver can be selected on the basis of the criteria outlined by Hercules in J. Simons, Adhesive Age, "The HMDA Concept: a new Method for Selection of Resins", November 1996. This reference explains the importance of polarity and the molecular weight of the resin when determining compatibility with the polymer. For substantially random interpolymers useful in the practice of the claimed invention, it is indicated that resins of low molecular polar weight are preferred. The adhesiveness enhancer (s) will typically be present in the composition of the invention in an amount of at least 10, typically at less than 20 weight percent. The adhesiveness enhancer (s) will be present in an amount of not more than 90, preferably not more than 75, and most preferably not more than 70 weight percent. In the case of substantially random interpolymers of at least one α-olefin and monovilidene aromatic monomer, preferred tackifiers will have the same degree of aromatic character to promote compatibility, particularly in the case of substantially random interpolymers having a high content of the monovilidene aromatic monomer. As an initial indicator, compatible adhesion enhancers are those that are also known to be compatible with ethylene vinyl acetate having 28 weight percent vinyl acetate. Particularly suitable classes of tackifiers include the Wingtack ™ 86 and the Hercotac ™ 1149 Eastman H-130, and the styrene / α-methylstyrene tackifiers. Another preferred tackifier is Piccotex 75, a pure monomer hydrocarbon resin having a glass transition temperature of 33 ° C, available with Hercules. It is noted that there is an unexpected benefit associated with the elevation of the glass transition temperature of a substantially random interpolymer by the addition of a compatible adhesiveness improver, in that when a compatible adhesive improver is used, it not only increases the temperature of the adhesive. transition to glass, but the tensile strength increases without a corresponding decrease in elongation at break, relative to the substantially random unmodified interpolymer. Although this effect is true for substantially random interpolymers having a higher or lower comonomer content, the effect is more pronounced for substantially random interpolymers having 45-65 weight percent of the monovinylidene or aliphatic aromatic comonomer prevented, which are the most elastomeric of the substantially random interpolymers. This is contrary to what was expected, since typically, when a brittle solid of low molecular weight is added to an elastomeric solid, the low molecular weight material dilutes the polymer network which leads to the tensile strength and elongation in the breakage which are lower than those of the polymer alone. Improved tensile strength has value in a number of applications, such as adhesives, elastomeric film applications, automotive parts, wire and cable caulking, durable goods (such as home appliances), packaging, and shoe soles. For example, in the case of adhesive formulations, it has been found that when the glass transition temperature of the substantially random interpolymer is less than -20 ° C, the composition exhibits poor peel strength and adhesiveness. However, by raising the glass transition temperature to 0 ° C by the addition of an adhesive enhancer, the release resistance of the formulation increases. In the case of improved blocking resistance, it is desirable to avoid binding or blocking of polymer pellets during transportation and storage. In this way, using the compositions of the invention which comprise a substantially random interpolymer and an adhesive improver, so that the glass transition temperature is above the temperature during transportation and storage, will increase the rigidity of the pellets of polymer, and will lead to a resistance to deformation during transportation and storage. In another embodiment, the pellets of a substantially random interpolymer can be coated with an adhesive improver to create a surface composition, which comprises the substantially random interpolymer and an adhesive enhancer that minimizes blocking. Compositions of the invention which comprise an adhesive improver will find additional utility in sound attenuation applications. For example, to attenuate a sound, a material must be capable of dissipating high levels of energy over the wide frequency range of normal sound under ambient conditions. This occurs when the glass transition temperature is from about -20 to about 10 ° C. The compositions of the invention, which exhibit a glass transition temperature on this scale, will attenuate sound in a variety of structures, such as automobiles. Processing aids, also referred to herein as plasticizers, are optionally provided to reduce the viscosity of a composition, such as an adhesive, and include phthalates, such as dioctyl phthalate and diisobutyl phthalate. , natural oils such as lanolin, and paraffin, naphthenic and aromatic oils obtained from the refining of petroleum, and liquid resins from raw materials of rosin or petroleum. The classes of exemplary oils useful as processing aids include white mineral oil (such as Kaydol ™ (available with Witco)), and naphthenic oil Shellflex ™ 371 (available from the Shell Oil Company). Another suitable oil is Tuflo ™ oil (available with Lyondell). When a processing aid is employed, it will be present in the composition of the invention in an amount of at least 5 percent. The processing aid will typically be present in an amount of not more than 60, preferably not more than 30, and most preferably not more than 20 weight percent. The composition comprising the substantially random ethylene interpolymer and at least one aromatic vinylidene monomer or hindered aliphatic vinylidene monomer, and an α-olefin of 3 to 20 carbon atoms, can optionally be modified by the inclusion of an extender or modifiers. Illustrative extender or modifier compositions include paraffin wax, a wax, of crystalline polyethylene, and / or a linear or substantially linear homogeneous ethylene / α-olefin interpolymer. Similarly, the composition of the invention may further comprise a linear or substantially linear homogeneous ethylene / α-olefin interpolymer as an extender or modifier composition. Modification of the composition with a linear or substantially linear homogeneous ethylene / α-olefin interpolymer, particularly when said interpolymer is an elastomer, will tend to extend the composition when the composition comprises a substantially random interpolymer having a high styrene content, and to improve the adhesiveness and modulus of the adhesive when the adhesive comprises a substantially random interpolymer having a low styrene content. The linear or substantially linear homogeneous ethylene / α-olefin interpolymer is an ethylene polymer prepared using a single-site metallocene, or a single-site constrained geometry catalyst. By the term homogeneous, it is meant that any comonomer is randomly distributed within a given interpolymer molecule, substantially all interpolymer molecules have the same ethylene / comonomer ratio within that interpolymer. The DSC melting peak of linear or substantially linear homogeneous ethylene polymers will widen as the density decreases and / or as the average molecular weight number decreases. However, unlike heterogeneous polymers, when a homogeneous polymer has a melting peak greater than 115 ° C (such as in the case of polymers having a density greater than 0.940 grams / cm), such polymers typically do not have a different low temperature melting peak. The homogeneous linear or substantially linear interpolymers useful in the invention further differ from the low density polyethylene prepared in a high pressure process. In one aspect, whether the low density polyethylene is an ethylene homopolymer having a density of 0.900 to 0.935 grams / cm3, the homogeneous linear or substantially linear interpolymer useful in the invention requires the presence of a comonomer to reduce the density up to the range of from 0.900 to 0.935 grams / cm3. Linear or substantially linear homogeneous interpolymers useful in the invention are typically characterized in that they have a narrow molecular weight distribution (Mw / Mn). For linear substantially linear interpolymers, the Mw / Mn is typically 1.5 to 2.5, preferably 1.8. to 2.2. In addition or alternatively, the homogeneity of the polymer can be described by SCBDI (abbreviations in English for Short Chain Branching Distribution Index) or CDBI (abbreviations in English for Composition Distribution Width Index), which they define as the weight percent of the polymer molecules having a comonomer content within 50 percent of the average total molar comonomer content. The Short Chain Branch Distribution Index is easily calculated from the data obtained from the techniques known in the art, such as, for example, fractionation of leaching from temperature rise (abbreviated herein as "TREF"). ), which is described, for example, in Wild et al., Journal of Polymer Science, Poly. Phys. Ed., Volume 20, page 441 (1982), in U.S. Patent No. 4,798,081 (Hazlitt et al.), Or U.S. Patent No. 5,089,321 (Chum et al.). The Short Chain Branching Distribution Index and the Composition Distribution Width Index for the homogeneous linear or substantially linear interpolymers useful in the invention is preferably greater than 50 percent, more preferably greater than 70 percent, with the Short Chain Branching Distribution Indexes and the Composition Distribution Width Index of more than 90 percent being easily obtained.

The substantially linear ethylene interpolymers are homogeneous interpolymers having long chain branches due to the presence of such long chain branches, the substantially linear ethylene interpolymers are further characterized because they have a melt flow rate (I? / I2) ) which can be varied independently of the polydispersity index, also called molecular weight distribution Mw / Mn. This feature harmonizes the substantially linear ethylene polymers with a high degree of processability despite a low molecular weight distribution. When a substantially linear ethylene interpolymer is employed in the practice of the invention, said interpolymer will be characterized in that it has a base structure substituted with 0.1 to 3 long chain branches per 1000 carbons. Methods for determining the amount of long chain branches present, both qualitatively and quantitatively, are known in the art. For qualitative methods for determining the presence of long chain branches, see, for example, US Patents Numbers 5,272,236 and 5,278,272. As stated therein, a gas extrusion rheometer (GER) can be used to determine the rheological processing index (PI), the critical shear rate at the beginning of the surface melt fracture, and the resistance to the critical shear stress at the beginning of the total fusion fracture, which in turn indicates the presence or absence of long chain branching as established above. For quantitative methods for determining the presence of long chain branching, see, for example, U.S. Patent Nos. 5,272,236 and 5,278,272; Randall (Rev. Macromol. Chem. Phys., C29 (2 and 3), pages 285-297), which explains the measurement of long chain branching using 13C nuclear magnetic resonance spectroscopy, Zimm, G.H. and Stockmayer, W.H., J. Chem. Phys., 17, 1301 (1949); and Rudin, A., Modern Methods of Polymer Characterization, John Wiley of Sons, New York (1991) pages 103-112, which explains the use of gel permeation chromatography together with an angle laser light scattering detector. low (GPC-LALLS) and gel permeation chromatography together with a differential viscometer detector (GPC-DV). In addition, A. Willem deGroot and P. Steve Chum, both of the Dow Chemical Company, at the conference of the Federation of Analytical Chemistry and Spectroscopy Society (FACSS) on October 4, 1994 at St. , Louis, Missouri, presented data demonstrating that gel permeation chromatography in conjunction with a differential viscometer detector is a useful technique for quantifying the presence of long chain branches in substantially linear ethylene polymers. In particular, deGroot and Chum found that the presence of long chain branches in substantially linear ethylene polymers correlated well, with the level of long chain branches measured using 13C NMR. The homogeneous linear or substantially linear extender polymer will be an interpolymer of ethylene with at least one α-olefin of 3 to 20 carbon atoms. Exemplary 3 to 20 carbon a-olefins include propylene, isobutylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, and 1-octene. Preferred 3 to 20 carbon atom a-olefins include 1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, and 1-octene, most preferably 1-hexene and 1-octene. The homogeneous linear or substantially linear extender polymer can also be an interpolymer of ethylene with at least one α-olefin of 3 to 20 carbon atoms, and a non-conjugated diene having 6 to 15 carbon atoms. Representative examples of suitable non-conjugated dienes include: (a) Straight chain acyclic dienes such as 1,4-hexadiene; 1,5-heptadiene; and 1, 6-octadiene; (b) Branched chain acyclic dienes such as 5-methyl-1,4-hexadiene; 3,7-dimethyl-1,6-octadiene; and 3,7-dimethyl-1, 7-octadiene; (c) Single ring alicyclic dienes such as 4-vinylcyclohexene; 1-Allyl-4-isopropylidenecyclohexane; 3- allylcyclopentene; 4-allylcyclohexene; and 1-isopropenyl-4-butenylcyclohexene; (d) Alicyclic fused multiple ring and branched ring dienes such as dicyclopentadiene; alkenyl, alkylidene, cycloalkenyl, and cycloalkylidene norbornenes, such as 5-methylene-2-norbornene; 5- (3-cyclopentenyl) -2- norbornene; 5-ethylidene-2-norbornene; 5-cyclohexylidene-2-norbornene; etc. The preferred non-conjugated dienes are selected from the group consisting of 1,4-hexadiene; dicyclo-pentadiene; 5-ethyl iden-2-norbornene; 5-methylene-2-norbornene; 7-methyl-1, 6-octadiene; piperylene; and 4-vinyl-cyclohexene. A suitable conjugated diene is piperylene. The ethylene / α-olefin interpolymer will have a density of 0.850 0.965 g / cm3, preferably 0.850 to 0.900 g / cm3 and most preferably 0.870 to 0.890 g / cm3. The ethylene / α-olefin interpolymer may be of high or low molecular weight. The numbers of suitable average molecular weights range from 3,000 to more than 100,000, preferably from 3,000 to 60,000. In certain applications, the use of ethylene / α-olefin interpolymers having a number average molecular weight of less than 20,000, preferably less than 12,000, will be preferred. Homogeneously branched linear ethylene / α-olefin interpolymers can be prepared using polymerization processes (such as the one described by Elston in U.S. Patent No. 3,645,992) which provide a homogeneous short chain branching distribution. In its polymerization process, Elston uses soluble vanadium catalytic systems to make such polymers. However, others such as the Mitsui Petrochemical Company and the Exxon Chemical Company have used so-called single site catalytic systems to make polymers that have a homogeneous linear structure. Homogeneous linear ethylene / α-olefin interpolymers are currently available with the Mitsui Petrochemical Company under the registered trademark "Tafmer" and with the Exxon Chemical Company under the registered trademark "Exact". The substantially linear ethylene / α-olefin interpolymers are available from The Dow Chemical Company as Affinity ™ polyolefin plastomers. In another diment, ultra low molecular weight ethylene polymers can be employed as an extender or modifier composition. The ultra low molecular weight ethylene polymers are described and claimed in the PCT patent application WO 97/26287. The ultra low molecular weight polymers employed will be either ethylene homopolymers or ethylene interpolymers and a comonomer selected from the group consisting of α-olefins of 3 to 20 carbon atoms, styrene, styrene substituted by alkyl, tetrafluoro methylene, vinylbenzocyclobutane, non-conjugated dienes, and cycloalkenes. The ultra low molecular weight polymer will have a number average molecular weight of less than 8200, preferably less than 6000, and most preferably less than 5000. Said ultra low molecular weight polymer will typically have a number average molecular weight of at least 800, preferably at least 1300. Ultra-low molecular weight polymers, in contrast to paraffin waxes and crystalline ethylene homopolymers or interpolymer waxes, will have an Mw / Mn, or from 1.5 to 2.5, preferably from 1.8 to 2.2.

The ultra low molecular weight polymers lead to low polymer viscosity and formulation, but are characterized by peak crystallization temperatures that are greater than the peak crystallization temperatures of corresponding higher molecular weight materials of the same density. In adhesive applications, the increase in peak crystallization temperature results in increased heat resistance, for example, improved slip resistance in pressure sensitive adhesives, and improved shear adhesion failure (SAFT) temperature in hot melt adhesives. When the ultra low molecular weight ethylene polymer is an ethylene interpolymer and at least one aromatic vinylidene comonomer or a hindered aliphatic vinylidene comonomer, it can be employed as an adhesiveness improver (as described above). In addition, as the molar percentage of ethylene is increased, the crystallinity of the interpolymer will also increase. Accordingly, the ultra low molecular weight ethylene interpolymers and less than 10 molar percent of the at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer can be useful as waxes to control the opening time and of closure of the adhesive system. In another form of a traditional wax, it remains to be used as an extender or modifier composition. Modification of the adhesive with a paraffin wax or a crystalline polyethylene wax will tend to improve the high temperature operation, such as resistance to deformation and SAFT, and reduce the opening and closing times of the adhesives comprising substantially random interpolymers, which have a high styrene content. Exemplary traditional waxes include ethylene homopolymers available from Petrolite, Inc. (Tulsa, OK) as PolywaxMR, 500, PolywaxM 1500, PolywaxMR 1000, and PolywaxMR 2000; and paraffin waxes available with CP Hall under the product designations 1230, 1236, 1240, 1245, 1246, 1255, 1260, and 1262. The PolywaxMR 2000 has a molecular weight of approximately 2000, an Mw / Mn of approximately 1.0, a density at 16 ° C of about 0.97 grams / cubic centimeter, and a melting point of about 126 ° C. Paraffin wax CP Hall 1246 is available with CP Hall (Stow, OH). Paraffin wax CP Hall 1246 has a melting point of 62 ° C, an adhesiveness at 99 ° C of 4.2 centipoise, and a specific gravity at 23 ° C of 0.915. Traditional waxes useful in the adhesives of the invention will typically have a density of at least 0.910 grams / cubic centimeter. Such waxes will have a density of not more than 0.970 grams / cubic centimeter, preferably not more than 0.965 grams / cubic centimeter.

Additives such as antioxidants (such as hindered phenols, for example, Irganox® 1010, Irganox® B900, and Irganox® 1076), phosphites (such as Irgafos® 168), ultraviolet stabilizers, may also be included in the compositions of the present invention. adhesion additives (such as polyisobutylene), antiblock additives, colorants, pigments, and fillers, to the extent that they do not interfere with the improved properties discovered by the applicants. The additives are employed in functionally equivalent amounts known to those skilled in the art. For example, the amount of antioxidant employed is that amount which prevents the polymer or composition from undergoing oxidation at the temperatures and in the environment employed during the manufacture, storage and final use of the polymers. Such amounts of antioxidants are usually in the range of from 0.05 to 10, preferably from 0.1 to 5, more preferably from 0.1 to 2 weight percent, based on the weight of the composition. When employed, the antioxidant is present more typically in an amount less than 0.5 percent by weight, based on the total weight of the composition. Similarly, the amounts of any of the other additives listed are functionally equivalent amounts, such as the amount to produce the polymer or mixture of anti-blocking polymer, to produce the desired amount of filler loading to produce the desired result, provide the desired color from the dye or pigment. These additives may typically be employed in the range of from about 0.05 to about 50, preferably from about 0.1 to about 35, most preferably from about 0.2 to about 20 weight percent, based on the weight of the substantially random interpolymer, although the filler may be employed in an amount of up to 90 percent by weight, based on the weight of the substantially random interpolymer. The compositions of the invention can be prepared by standard melt blending procedures. In particular, the substantially random interpolymer (s), adhesiveness improver (s), and optional processing aid (s) can be melt mixed at a suitable temperature to achieve the formation of a homogeneous melt mixture, typically at temperatures of from 100 to 200 ° C, and under a blanket of inert gas, until a homogeneous mixture is obtained. Any mixing method which produces a homogeneous mixture without degrading the hot melt components, such as by the use of a heated vessel equipped with a stirrer, is satisfactory. In addition, the substantially random interpolymer (s), adhesiveness improver (s), and the optional modifier (s) optional extender (s) (s) can be provided to an extrusion coater for application to the substrate. The compositions can also be prepared in a multi-reactor process, for example, by producing the substantially random interpolymer in a reactor, and more polymer component (such as a low extra-molecular weight polymer or wax) in a second reactor, optionally introducing other components within the second reactor, or at a point downstream of the second reactor, such as by a side arm extruder. In a preferred embodiment, the composition of the invention will be provided in the form of an adhesive comprising at least one substantially random interpolymer. Typically, the adhesive will comprise from 5 to 75 weight percent of at least one tackifier, more preferably from 10 to 70 weight percent of at least one tackifier. As stated above, the adhesiveness enhancer will preferably have an aromatic character. In some cases, the tackifier will be an ultra low molecular weight ethylene interpolymer, and at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer, interpolymer comprising at least 25 mole percent of at least one aromatic comonomer of vinylidene or aliphatic vinylidene comonomer hindered. The adhesive of the invention may also comprise at least one modifier composition, as described above. When this modifier composition is employed, it will typically be present in the adhesive system in an amount of from 5 to 75 weight percent. A modifier composition is a traditional wax or an ultra low molecular weight ethylene polymer. In some cases, the ultra low molecular weight ethylene polymer will be an ethylene interpolymer, and at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer, interpolymer comprising less than 10 mole percent is at least one aromatic comonomer of vinylidene or aliphatic vinylidene comonomer hindered. On the other hand, the adhesive of the invention may comprise a plurality of substantially random interpolymer components that differ in the amount of aromatic monomer content of vinylidene or hindered aliphatic vinylidene monomer, which differ in molecular weight, or which differ both in the amount of aromatic monomer of vinylidene or hindered aliphatic vinylidene monomer, and in molecular weight. It will be apparent that an adhesive containing a very high content of the substantially random interpolymer can be designed. For example, an adhesive may comprise as the adhesive imparting component, from 5 to 75 weight percent of a substantially random ethylene interpolymer, and at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of more than about 10,000, and comprises from 10 to less than 25 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer; as a wax, from 5 to 75 weight percent of a substantially random ethylene interpolymer, and at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of less than about 8,200, and comprising from 1 to less than 10 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer; and as an adhesive improver, from 5 to 75 weight percent of a substantially random ethylene interpolymer, and when we receive an aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of less than about 8,200, and comprises at least 25 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer. As stated in J. Class and S. Chu, Handbook of Pressure Sensitive Adhesive Technology, Second Edition, D. Satas, e., 1989, pages 158-204, the requirements for a pressure-sensitive adhesive behavior can be defined by the elastic adhesive properties dependent on the temperature and speed of the materials and the formulations. Broadly speaking, to be suitable pressure sensitive formulations, the formulations should have a glass transition temperature of from -20 to 25 ° C, preferably from -10 to 10 ° C, as reflected by the peak tanning temperature gives 1 radian per second, as determined by dynamic mechanical spectroscopy. Wide transition peaks to the glass are preferred, because when the peak is large, the adhesive will operate over a wider temperature range, thereby increasing its usefulness. In addition, adhesives having a broader glass transition peak will typically be characterized by increased adhesiveness and peel strength. In accordance with what has become known as the Dahiquist criteria, broadly speaking, to be a suitable pressure sensitive formulation, the formulation must have a shear stress modulus at 25 ° C to 1 radian per second, which is between 1 x 105 and 6 x 106 dynes / square centimeter, preferably between 1 x 105 and 3 x 105 dynes / square centimeter, as determined by dynamic mechanical spectroscopy. A stiffer material than this, that is, a material having a shear stress modulus at 25 ° C of 1 X 107 dynes / square centimeter, will not exhibit surface tack at room temperature. A material less stiff than this, that is, a material having a flat shear stress modulus at 25 ° C of 1 x 104 dynes / square centimeter, will lack sufficient cohesive force to be useful. In particular, the preferred pressure sensitive adhesives for use in low release labels will have a G 'of from 3 x 105 to 1 x 106 dynes / square centimeter (0.3 to 1 MPa), and a glass transition temperature of from -50 to -30 ° C. Preferred pressure sensitive adhesives for use in freezer labels will have a G 'of from 8 x 104 to 2 x 105 dynes / square centimeter (0.08 to 0.2 MPa), and a glass transition temperature of from -45 to - 30 ° C. Preferred pressure sensitive adhesives for use in labels at cold temperatures will have a G 'of from 2 x 105 to 1 x 106 dynes / square centimeter (0.2 to 1 MPa) and a glass transition temperature of from -25 up to - 10 ° C. Preferred pressure sensitive adhesives for use in pressure sensitive adhesive tapes will have a G 'of from 7 x 105 to 5 x 106 dynes / square centimeter (0.7 to 5 MPa), and a glass transition temperature of from - 10 to 10 ° C. Preferred pressure sensitive adhesives for use in high release labels will have a G 'of from 2 x 105 to 6 x 105 dynes / square centimeter (0.2 to 0.6 MPa), and a glass transition temperature of from 0 to 10 ° C. Preferred pressure sensitive adhesives for use in disposables will have a G 'of from 4 x 105 to 2 x 106 dynes / square centimeter (0.4 to 2 MPa), and a glass transition temperature of from 10 to 30 ° C. The glass transition temperature is a function of the adhesiveness-improving content, the presence and amount of processing aid, and the styrene content and the molecular weight of the substantially random interpolymer. In accordance with the foregoing, to raise the glass transition temperature of the composition of the invention, one can increase the amount of, or the glass transition temperature of the tackifier, decrease the amount of the processing aid, or increase the amount of the aromatic vinylidene monomer or hindered aliphatic vinylidene monomer in the substantially random interpolymer. The shear stress modulus is a function of the presence and amount of processing aid and styrene content and the molecular weight of the substantially random interpolymer. To decrease the G ', one can increase the amount of the processing aid in the composition or increase the amount of the aromatic vinylidene monomer or hindered aliphatic vinylidene monomer in the substantially random interpolymer. The compositions of the invention will be useful in applications where adhesives are typically employed, particularly hot melt adhesives. Some representative examples include packaging, box and cardboard sealing, binding, lamination of coatings to a substrate, tapes, and labels. The compositions can also be used in multilayer food packaging structures, wherein at least one layer of the structure is aluminum. The compositions can be easily extruded onto a variety of substrates, including, but not limited to, under-carpets, tile and floor sheets, and woven and non-woven fabric. Similarly, the compositions can be molded in a variety of ways, including, but not limited to, shoe soles, seals, toys, durable articles, wire and cable, and packaging. The following Examples are provided to illustrate the particular embodiments of the claimed invention, rather than to limit the scope of the invention thereto.

Example 1: Preparation of Adhesives Based on Substantially Random Ethylene Interpolymers and a Monovinylidene Aromatic Comonomer Polymerization of Substantially Random Ethylene Interpolymers and a Monovinylidene Aromatic Comonomer Polymer A was prepared in a one gallon (3.8 liter) batch reactor, with semicontinuous agitation. The reaction mixture consisted of about 1100 grams of cyclohexane and 818 grams of styrene. Prior to the addition to the reactor, the solvent, styrene and ethylene were purified to remove water and oxygen. The inhibitor in styrene was also removed. The temperature in the vessel was controlled to a set point of 60 ° C by varying the flow of refrigerant in the reactor cooling coils. The pressure in the vessel was then monitored at a set point of 100 psig (4.8 kPa) with ethylene. Hydrogen was added in a controlled manner to control molecular weight. The flow of the catalyst components was controlled, comprising a catalyst containing monocyclopentadienyl titanium, such as titanium: (N-1,1-dimethylethyl) dimethyl (1- (1,2,3,4,5-eta) - 2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl) silanaminate)) (2-) N) -dimethyl, CAS # 135072-62-7, Tris (pentafluorophenyl) boron, CAS # 001109-15-5, methylaluminoxane, modified Type 3A, CAS # 146905-79-5, on a molar ratio basis of 1 / 1.5 / 20 respectively, and combined and added to the vessel. After the start, the polymerization was allowed to proceed with ethylene supplied to the reactor as required to maintain the container pressure. In this case, approximately 50 grams of ethylene was charged into the reactor, ethylene flowed into the reactor at a maximum rate of 5.6 grams / minute, and the total amount of ethylene added was 87 grams. The bullfight continued for 30 minutes. At the end of the run, the catalyst flow was stopped, the ethylene was removed from the reactor, then approximately 1000 ppm of antioxidant lrganox ™ 1010 was added on a polymer base, to the solution and the polymer was isolated from the solution. The resulting polymers can be isolated from the solution by stripping through the use of a devolatilizing extruder.

Preparation of Adhesive Formulations The substantially random interpolymer, the adhesive improver, the plasticizer, the styrene block copolymer, and the indicated antioxidant were added simultaneously, in the indicated quantities to a Haake Rheocord 40 mixer, using a mixing bowl of 200 grams, maintained at 100 ° C. approximately 130 ° C at 95 revolutions per minute. The ingredients were mixed for about 5 minutes, until they were fused. Petroleum hydrocarbon resin Escorez ™ 5300 is an adhesive improver available from the Exxon Chemical Company (Houston, TX). The hindered phenolic antioxidant lrganoxMR B900 is available with Ciba-Geigy. Primoil 355 is a mineral oil. Example 1 was tested to see its initial viscosity, and its viscosity after three days, using a Brookfield viscometer at 177 ° C, the probe adhesiveness, the modulus (G '), and the tan delta peak. Table 1 shows the formulations and the properties measured. Note that in the case of the tan delta module and tan, the reported values were extracted from a computer generated graph of the results.

TABLE ONE As illustrated in Table One, the adhesive of Example 1 meets the Dahiquist criteria, indicating its convenience as a traditional pressure sensitive adhesive. The adhesive of Example 1 is also preferred because it has a glass transition temperature in the range of -45 to 30 ° C. The data with respect to Example 1, taken in conjunction with the Dahiquist criteria, suggest that the adhesive of Example 1 can be suitably employed as a high release label and / or as a pressure sensitive adhesive tape.

Examples 2-8 v Comparative Examples A and B; Hot Melt Adhesives for Bonding Aluminum Preparation of Ethylene and Styrene Interpolymers B and C The polymer was prepared in a batch reactor of 400 gallons (1500 liters), of semicontinuous agitation, using the process conditions stated in the following Table Two. The reaction mixture consisted of approximately 250 gallons (950 liters) of a solvent comprising a mixture of cyclohexane (85 weight percent) and isopentane (15 weight percent), and styrene. Before the addition, the solvent, styrene and ethylene were purified to remove water and oxygen. The inhibitor in styrene was also removed. The inerts were removed by means of purging the container with ethylene. The pressure of the container was then monitored at a set point with ethylene. Hydrogen was added to control the molecular weight. The temperature in the container was controlled to a set point by varying the water temperature of the cover in the container. Before polymerization, the vessel was heated to the desired run temperature and the flow of the catalyst components was controlled: titanium: (N-1, 1-dimethylethyl) dimethyl (1 - (1, 2,3,4, 5 -eta) -2,3,4, 5-tetramethyl-2,4-cyclopentadien-1-yl) silanaminate)) (2) N) -dimethyl, CAS # 135072-62-7, Tris (pentafluorophenyl) boron, CAS # 001109-15-5, Modified methylaluminoxane Type 3A, CAS # 146905-79-5, on a molar ratio basis of 1/3/5 respectively, were combined and added to the vessel. After the start, the polymerization was allowed to proceed with ethylene supplied to the reactor as required to maintain the container pressure. In some cases, hydrogen was added to the headspace of the reactor to maintain a molar ratio with respect to the ethylene concentration. At the end of the run, the catalyst flow was stopped, the ethylene was removed from the reactor, then approximately 1000 ppm of antioxidant lrganoxMR 1010 was added to the solution and the polymer was isolated from the solution. The resulting polymers were isolated from the solution by stripping through the use of a devolatilizing extruder.

TABLE TWO * Total percentage by weight of styrene measured by the Infrared Fourier Transform (FTIR) technique. Table 3 gives the characteristics of the interpolymer and the vinyl aromatic polymer. The non-combined polymers provide the comparative examples of this invention. The test parts and characterization data for the interpolymers were generated according to the following procedures: The plates are pressure molded as follows. The samples are melted at 190 ° C for 3-minutes and molded by pressure at 1900C under 9,072 kilograms of pressure for another 2 minutes. Subsequently, the molten materials were cooled in a balanced press at room temperature. The determinations by differential scanning calorimetry (DSC) were made as follows. A DuPont DSC-2920 was used to measure the thermal transition temperature and transition heat for the interpolymers. In order to eliminate the previous thermal history, the samples were first heated to 200 ° C. Heating and cooling curves were recorded at 10 ° C / minute. The melting (second heating) and crystallization temperatures were recorded from the peak temperatures of the endotherm and the exotherm, respectively. The determinations of rheology of shear stress by fusion were made as follows. Measurements of oscillatory shear rheology were performed with a rheometer Rheometrics RMS-800 rheological properties were monitored at an isothermal set temperature of 190 ° C in a frequency sweep mode. In the tabulated data,? Is the viscosity y? (1 OO / 0.1) is the ratio of the speed of the recorded values to frequencies of 100 / 0.1 rad / second. The Shore A hardness was measured at 23 ° C following ASTM-D240. The flexure module was evaluated in accordance with ASTM-D790. The tensile properties of compression molded samples, were measured using an Instron 1145 traction machine, equipped with an extensometer. Samples of ASTM-D638 were tested with a tensile index of 5 min. "The average of four tensile measurements is given.The deformation tension and the tensile strain at the point of inflection in the tension / traction The energy in the break is the area under the tensile / tensile curve The relaxation of the tension by traction was determined as follows The stress relaxation by uniaxial traction was evaluated using an Instron 1145 tension machine. compression molded (approximately 20 thousand, 0.0508 centimeters thick) with a gauge length of 2.54 centimeters, was deformed to a tensile level of 50 percent at a tensile index of 20 min "1. The force required to maintain the 50 percent elongation was monitored for 10 minutes. The magnitude of tensile stress relaxation is defined as (f, -ff / f?), Where f, is the initial force and ff is the final force. Thermomechanical analysis data (TMA) were generated using a Perkin Elmer series TMA 7 instrument. The penetration of a 1 millimeter probe was measured in compression molded parts of 2 millimeters thickness, using a heating index of 5 ° C / minute and a load of 1 Newton.

Table Three Components of the mixture of interpolymer and vinylidene aromatic polymer Measured by the NMR technique. 2 Proportion of? (1.6) /? (0.1). The formulations described in Table Four were prepared in a 60 milliliter Brabender mixer, using roller blades. The bowl was heated to 130 ° C before the introduction of the polymer. The speed of the blade was 30 revolutions / minute. After the polymer was melted (approximately 5 minutes) the other ingredients were added in small portions, for a period of 10 to 30 minutes. The speed of the addition depended on the speed at which mixing incorporated the material into the mixture. Where there was a large mismatch in the melt viscosity of the materials being mixed, higher temperatures and longer mixing times were used. After the addition was completed, mixing was continued for 10 minutes, or until the sample was visually homogeneous. Adhesion samples were prepared from aluminum foil tapes 3.17 x 15 centimeters 0.002 centimeters thick. It was cleaned by rubbing the surface with methylethyl ketone before gluing, to remove any surface contamination. Samples were prepared in a tetrahedral press with the plates set at 177 ° C. The samples were compression molded between layers of silicone release paper, using the following cycle: (1) equilibrate 30 seconds at 177 ° C under contact pressure, (2) jump the pressure of the ram to 11.2 kilograms / square centimeter, (3) keep the pressure for 2 minutes and release. The pressure corresponds to approximately 1.4 kilograms / square centimeter in the samples. Samples were tested on the T-detach geometry (ASTM-1876), using an Instron tensile tester. The crosshead speed was 2.5 centimeters / minute. Table 4 shows the composition and operation of the sample.

Table Four Wingtack is a registered trademark of Goodyear. Hercotac is a registered trademark of Hercules. Eastotac is a registered trademark of Eastman Chemical. Polywax is a registered trademark of Petrolite. A comparison of Examples 3 to 6 of Table Four illustrates the fact that formulations that include an appropriate adhesive improver exhibit peel strengths that are better than those of the non-ethylene / styrene interpolymer. Formulation 7 illustrates the negative effect of an incompatible or only partly compatible adhesive improver. As illustrated in Example 8, the addition of wax to the high peel strength adhesive of Example 3 decreases the peel strength compared to that of the adhesive of Example 3, but results in a peel strength that is greater than that of the formulations based on the ethylene / octene comparative interpolymer of Comparative Examples A and B.

Examples 9-21 and Comparative Examples C. D. v E: The formulations used in the following examples were prepared in the manner stated above. In the case of Examples 9-12, the polymer used was Polymer D, a substantially random ethylene / styrene interpolymer having 42 weight percent styrene and a melt index (I2) of 1 gram / 10 minutes. In the case of Examples 13-16, the polymer used was polymer E, a substantially random ethylene / styrene interpolymer having 57 weight percent styrene. In the case of Examples 17-21, the polymer used was polymer F, a substantially random ethylene / styrene interpolymer having 65 weight percent styrene. The adhesiveness improver used was Piccotex 75, which is a pure monomer resin that has a glass transition temperature, as determined by differential scanning calorimetry., of 31 ° C, and that is available with Hercules. The extensor or modifier composition used was Tuflo 6056, which is a mineral oil available with Lyondell Petrochemical. The resulting formulations were evaluated to see their glass transition temperature, breakthrough tensile, elongation at break, bond strength, G ', 100 percent modulus, 200 percent modulus, and tenacity. In the case of tensile determinations, the samples were molded at 115 ° C for 5 minutes at a 10-ton rammer pressure. Samples that were 2.54 centimeters by 0.318 centimeters were used. The Instron tensometer was adjusted to a crosshead speed of 50 centimeters / minute. The module was taken as the slope of the tension-traction curve to an extent of 100 and 200 percent (as measured by crosshead displacement). Tenacity was the area under the tension-traction curve. In the case of the G 'determinations, a Rheometrics RDSII Solids Analyzer was used, with parallel plates of 8 millimeters in diameter, operated in the shear stress mode. The speed of the test was 1 radian / second. The temperature was modified in stages from 5 to 10 ° C, and allowed to equilibrate for 2 minutes before data collection. In the following Table Five the formulations and the resulting properties are exposed.

TABLE FIVE A TABLE FIVE B or Table Five shows that the addition of the tackifier to a substantially random ethylene / styrene interpolymer increases the tensile strength of the interpolymer. This increase in toughness (the result of increased tensile hardening of the formulation) contributes to an increase in the peel strength of a sample for bonded aluminum tests. The aluminum-aluminum joints are made at 177 ° C for 120 seconds, under a pressure of 8 pounds / square inch (0. 055 MPa). As illustrated in Table Six, the addition of the adhesion enhancer to a substantially random ethylene / styrene interpolymer has the ability to increase the toughness of a substantially random ethylene / styrene interpolymer having less than 5 percent crystallinity by calorimetry. of differential exploration, that is, that is predominantly amorphous in character.

Examples 21-23 and Comparative Examples F and G; PSA tapes Samples of pressure-sensitive adhesive tapes were prepared, by coating from the melt on a 0. 051 millimeter thick polyester liner, and covered with silicone release paper for storage and transport. The coater was a commercial unit available with Chemsultants International. The adhesive layers were in the range of 0.09 to 0.115 millimeters in thickness. Tests were performed in accordance with the standards of the Pressure Sensitive Tape Council (PSTC). A peel test was performed at 180 ° C on stainless steel, at 30 centimeters / minute, at intervals of both 5 minutes and 24 hours. The shear stress tests (Retention Energy) were performed at room temperature, with a load of 1000 grams and a cover of 12.7 x 25.4 millimeters in polished stainless steel as a mirror. In the case of Comparative Example F, the polymer was the styrene / isoprene / styrene block copolymer Vector 4113, available from the Dexco Company. In the case of Comparative Example G, the polymer was the styrene / isoprene / styrene block copolymer Vector 4114, available from the Dexco Company. In the case of Examples 21-23, the polymer was the substantially random interpolymer of Polymer E. In the following Tables Six and Seven the formulations employed and the resulting adhesive properties are set forth: Table Six Table Seven Tables Six and Seven show that substantially random ethylene / styrene interpolymers having from 39 to 65, preferably from 45 to 55, weight percent styrene, can be formulated to give adhesive formulations sensitive to low adhesive pressure, with slip resistance, compared to styrene block copolymer formulations.

Classification Study of the Adhesive Meiorador In the following Table Eight the adhesivity improvers evaluated in the study are exposed, as well as properties obtained from commercial literature: Table Eight * The DACP nebulosity point reflects the polarity of the resin, with the lowest values indicating a greater degree of polarity. The point of nebulosity MMAP is a value that reflects the aromatic compatibility of the resin, with the lowest values indicating a greater degree of aromaticity. The formulations were prepared and evaluated, the formulations employed and the resulting properties being exposed in the following Table Nine.

Table Nine shows that a wide variety of adhesive enhancer structures can improve the tensile properties of substantially random interpolymers. The adhesion enhancers of the families of rosin ester, wood rosin, pure monomer, C5-C9, modified aromatic C5, partially hydrogenated C5-C9, and cycloaliphatic families have been shown to be effective. Of particular and unexpected nature in Table Nine is that the combination of, for example, 100 parts of adhesive improver with 100 parts of the substantially random interpolymer components results in materials having much higher tensile strengths than the substantially random interpolymer alone, preferably a maximum tensile strength of less twice, and most preferably at least three times as large as that of the interpolymer substantially randomly alone.

Transition Temperature Adjustment to Glass for Polymers with High Styrene Content A substantially random interpolymer of ethylene and styrene having from 73.7 to 74.9 percent by weight of styrene and a melt index (12) of 1 g / 10 minutes, was mixed under fusion with the indicated amount of the pure monomer resin Endex ™ , available with Hercules. The formulations tested, and the glass transition temperature of the resulting formulations are set forth in the following Table Ten.

Table Ten The data set forth in Table Ten illustrates the use of an adhesive improver to raise the glass transition temperature of an interpolymer with a high styrene content to levels above room temperature. These and other modalities will be readily understood by one skilled in the art. In accordance with the foregoing, the present invention will be limited only by the following claims.

Claims (18)

1. A composition comprising: (a) from 5 to 95 weight percent of at least one substantially random interpolymer, from 35 to 99 molar percent of ethylene and from 1 to 65 molar percent of the vinylidene aromatic monomer, or of the monomer of hindered aliphatic vinylidene; and (b) from 5 to 95 weight percent of at least one tackifier improver. The composition of claim 1, wherein the substantially random interpolymer further includes at least a third conmonomer selected from the group consisting of α-olefins of 3 to 20 carbon atoms. The composition of claim 1, wherein the at least one substantially random interpolymer is an interpolymer of ethylene and an aromatic vinylidene monomer represented by the following formula: wherein R1 is selected from the group of radicals consisting of hydrogen and alkyl radicals containing three carbon atoms or less, and Ar is a phenyl group or a phenyl group substituted with from 1 to 5 substituents selected from the group consisting of halogen , alkyl of 1 to 4 carbon atoms, and haloalkyl of 1 to 4 carbon atoms. The composition of claim 1, wherein the substantially random interpolymer is an interpolymer of ethylene, an aromatic vinylidene monomer or a hindered aliphatic vinylidene monomer, and at least one third monomer selected from the group consisting of α-olefins of 3 to 20 carbon atoms and norbornene. The composition of claim 1, wherein the composition comprises from 25 to 95 percent by weight of substantially random interpolymer, and from 5 to 75 percent by weight of at least one adhesive improver. The composition of any of the preceding claims, wherein at least one adhesiveness improver is selected from the group consisting of wood rosin, wood pulp oil derivatives, cyclopentadiene derivatives, natural and synthetic terpenes, terpenphenolics, resins of styrene / α-methylstyrene, and mixed aliphatic-aromatic adhesion resins. The composition of claim 1, wherein the composition further comprises from 5 to 75 weight percent of at least one modifier or paver composition selected from the group consisting of paraffin waxes, crystalline polyethylene waxes, weight ethylene polymers ultra-low molecular weight, linear or substantially linear homogeneous ethylene / α-olefin interpolymers, polystyrene, styrene block copolymers and ethylene vinyl acetate and amorphous polyolefins. The composition of claim 1, wherein the composition comprises from 1 to 60 weight percent of one or more processing aids, selected from the group consisting of phthalate esters, natural oils, paraffinic oils, naphthenic oils, and aromatic oils The composition of any of the preceding claims, characterized in that it is in the form of an adhesive, a layer of a multilayer food packaging structure, a coating, a sealant, or a molded article, calendered article or extruded article. 10. An adhesive comprising the composition of any of the preceding claims, and which further comprises a component selected from the group consisting of linearly homogeneous ethylene / α-olefin linear, ethylene / α-olefin interpolymers, ultra-low molecular weight ethylene polymers. , processing aids and mixtures thereof. The adhesive of claim 10, wherein the substantially random interpolymer comprises from 25 to 65 weight percent of the aromatic vinylidene monomer or hindered aliphatic vinylidene monomer. The adhesive of claim 10 or 11, wherein the adhesive comprises a plurality of substantially random interpolymer components, which differ in the amount of vinylidene aromatic monomer or aliphatic vinylidene monomer content., which differ in molecular weight, or which differ both in the amount of aromatic monomer content of vinylidene or hindered aliphatic vinylidene monomer and in molecular weight. The adhesive of claim 12, characterized in that it comprises: (a) 5 to 75 weight percent of a substantially random ethylene interpolymer, and at least one aromatic vinylidene comonomer, or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of more than about 10,000, and comprises from 10 to less than 25 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer; (b) 5 to 75 weight percent of a substantially random ethylene interpolymer, and at least one aromatic vinylidene comonomer, or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of less than about 8,200, and ranging from 1 to less than 10 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer; and (c) 5 to 75 weight percent of a substantially random ethylene interpolymer, and at least one aromatic vinylidene comonomer, or hindered aliphatic vinylidene comonomer, interpolymer having an Mn of less than about 8,200, and comprising at least 25 mole percent of the at least one aromatic vinylidene comonomer or hindered aliphatic vinylidene comonomer. The adhesive of any of claims 10-13, wherein the substantially random interpolymer is an interpolymer of ethylene, at least one aromatic vinylidene monomer, and optionally at least one α-olefin monomer. 15. The adhesive of any of claims 10-14, as applied to a substrate selected from the group consisting of packs, cardboard, binding, tape, label, decal, bandage, decorative sheet, protective sheet, ceramic tile, tile vinyl, vinyl floor, under-carpet, non-woven fabric, woven fabric, placement tape for personal hygiene device, sun control film, packing, filler, wood, or coating. 16. A coextruded or laminated multilayer film, wherein at least one layer comprises an adhesive comprising at least one substantially random ethylene interpolymer, and an aromatic vinylidene monomer, or a hindered aliphatic vinylidene monomer, and optionally when minus one α-olefin monomer of 3 to 20 carbon atoms. 17. The coextruded or laminated multilayer film of claim 16, wherein the adhesive is adhered to a sheet of metal. A tape comprising a substrate to which an adhesive has been applied comprising: a) from 40 to 60 weight percent of a substantially random ethylene interpolymer, and an aromatic vinylidene monomer, or a hindered aliphatic vinylidene monomer , and optionally at least one α-olefin monomer of 3 to 20 carbon atoms, the substantially random interpolymer comprising from 25 to 65 weight percent of vinylidene aromatic monomer, or hindered aliphatic vinylidene monomer, b) from 40 to 60 weight percent of an adhesive improver, and c) from 0 to 10 weight percent of a processing aid, wherein the adhesive is characterized in that it has a storage module (C) at 25 ° C from 2 x 105 to 5 x 106 dynes / square centimeter (0.2 to 5 MPa).