MXPA98004992A - Process to prepare a lamin - Google Patents

Abstract

The present invention relates to a process for preparing a laminate comprising a first substrate (I) and a second substrate (II), which comprises an ethylene or propylene polymer and which is joined to the first substrate by means of a polymeric adhesive, wherein the process comprises the steps of: A) applying to the first substrate (I) a primer comprising an organic solvent and an ethylene or propylene polymer having thereto grafted a carboxylic acid or an anhydride, ester, amide, imide or metal salt of the same, and B) injection molding an ethylene or propylene polymer and optional additives on the primed substrate (

Description

PROCESS FOR PREPARING A LAMINATE The present invention relates to a process for preparing a laminate, which comprises two substrates that are joined together by means of a polymeric adhesive, one of the substrates comprising an ethylene or propylene polymer. It is well known that polyolefins do not adhere to polar materials, such as metals, concrete and polar resins. There are vain methods both for modifying the polyolefins and for applying an adhesive between the polyolefin and the polar substrate in order to improve adhesion. The Patent of E.U.A. No. 4,599,385, discloses graft copolymers wherein maleic acid or maleic anhydride is grafted onto a structure of the crystalline base of poly (propylene-butene). The graft copolymer can be used as a primer layer between the polar substrate and the polar polypropylene or it can be mixed with polypropylene and the mixture can be applied directly. If the graft copolymer is used as a primer layer, it is usually applied to the polar substrate as a powder coating and adhered to the substrate by heating and melting in a continuous film. Alternatively, the graft copolymer can be dissolved in a hot solvent and applied by brushing or spraying. The application of the polypropylene layer to the primed substrate can be achieved by extrusion coating or lamination with a preformed film.

The Patent of E.U.A. 4,599,385, teaches that powder coating is preferred followed by melting. However, special equipment is required for the powder coating and the types of materials are imitated to those to which the powder coating can be applied. Alternatively, when the graft copolymer is mixed with polypropylene and the mixture is applied directly, higher amounts of the graft copolymer are required to obtain sufficient adhesion. Coextrusion techniques are recommended for preparing polypropylene laminates and polar polymer films using the graft copolymer as an adhesive. In these techniques, the molten polypropylene graft copolymer layers are extruded simultaneously to form a layered sheet. Naturally, this technique is limited to thermoplastic polymers that can be co-extruded. The Patent of E.U.A. 4,198,327 describes a composition having improved adhesion to polar solid materials. The composition comprises (A) from 99 to 70 parts by weight of a modified crystalline polyolefin having grafted thereto, a monomer selected from unsaturated carboxylic acids and their anhydrides, esters, amides, imides and saies of metals and (B) from 1 to 30 parts by weight of a hydrocarbon elastomer. The polyolefin composition can be attached to a polar material by heating them in such a way that at least the polyolefin composition melts and then binds to them under pressure. When the polar material is not thermoplastic, the molten composition can be coated or laminated on the polar material. However, the patent of E. U.A. it does not suggest how to achieve adhesion between a polar material and an unmodified polyolefin. The Patent of E. U.A. 5,302, 418, discloses a process for coating a polypropylene or polyethylene surface with a polypropylene or polyethylene grafted with maleic acid, which contains from 0.5 to 10 weight percent, preferably, at least 4 percent maleic acid. In this process, the surface is coated with a lubricant comprising the graft copolymer and a solvent at a coating temperature which is sufficient to keep the graft copolymer dissolved in the solvent, ie from 85 ° C to 100 ° C . The lubricant contains from 2 to 15 weight percent, preferably from 3 to 10 weight percent solids. The solvent is an aromatic solvent, such as toluene. The lubricant must be hot enough to keep the copolymer dissolved in the lubricant solvent until the copolymer binds to the surface. The process is mainly useful for coating polypropylene fibers. European Patent Application EP-0 407 666 A 1 discloses a method for the surface treatment of a molded and cured rubber article made of a polyolefin. To produce the molded article, rubber (EPDM) formed by copolymerization of ethylene, an α-olefin and a diolefin are used and mixed with a softener, a filler and a curing agent. The mixture is molded in the desired configuration by a molding machine extrusion Cured EPDM rubber is used in automotive molded articles Articles are usually painted In order to improve the adhesion of the paint to the molded articles, the articles are treated with a solution of a modified polymer having an intrinsic viscosity of at least 0 3 in an organic solvent The polymer is modified by copolymeation of the graft of a propylene-ethylene copolymer with maleic acid or anhydride thereof The content of propylene is 10 to 90 percent molded, especially 20 at 80 percent molar. The concentration of the modified polymer is 10 to 100 kg / m 3 of solvent, preferably 20 to 60 kg / m 3 of solvent. After this surface treatment, the cured molded rubber article is additionally coated with a paint or other resin coating material by electrostatic coating, spray coating or brush coating. Patent of E U to 4,299,754. suggests a solution of a similar modified graft polymer as an agent for treating surfaces for articles made of polyolefins, such as automobile stops. The propylene content in the modified graft polymer is 50 to 75 mole percent. The U.A. Patent No. 4,058,647 discloses that a polyester, a polymer or a hydrolyzed copolymer of ethylene-vinyl acetate can be laminated with a polymeric composition comprising both a modified and an unmodified poiioiephine and a rubber component. The modified polyolefin is modified with an acid unsaturated or ahnidpdo The laminate is prepared by press sheets made of the same materials mentioned above or by a blow molding process to form sheets.

US Patent 4,588,648 discloses that polypropylene and nylon layers can be laminated with an adhesive layer comprising a mixture of an ungrafted polypropylene and a maleic anhydride graft copolymer in an olefin polymer.

The laminate is produced by co-extrusion. However, the described methods are not suitable for preparing laminates containing a natural or synthetic material, which can not or should not be melted, such as skin, cotton, jute or synthetic leather. An object of the present invention is to provide a novel process for preparing a laminate comprising two substrates which are joined to each other by means of a polymeric adhesive, one of the substrates comprising an ethylene or propylene polymer. For example, in the footwear industry, there is a great need for methods that are useful in the production of laminates containing an ethylene or propylene polymer as a first substrate and containing a second substrate that can not or should not be melted during the production of the laminate, such as rubber, skin, manufactured natural fibers, or a synthetic resin similar to synthetic leather or a polyamide.

Accordingly, another object of the present invention is a new process for preparing a laminate mentioned above that does not make use of a co-extrusion process. One aspect of the present invention is a process for preparing a laminate comprising a first substrate (I) and a second substrate (II) which comprises an ethylene or propylene polymer and which is adhesively bonded to the first substrate by means of a polymeric adhesive, wherein the process comprises the steps of: A) applying to the first substrate (I) a primer comprising an organic solvent and an ethylene or propylene polymer having an inserted carboxylic acid or an anhydride, ester, grafted thereto; amide, measure or metal salt thereof, and B) injection molded an ethylene or propylene polymer and optional additives in the primed substrate (I). Another aspect of the present invention is a laminate that has been produced according to the aforementioned process. A preferred aspect of the present invention is footwear that has been produced according to the process mentioned above. The laminates produced exhibit excellent adhesion between the second substrate, which comprises an ethylene or propylene polymer, and the first substrate, which may be polar. The process of the present invention is very efficient. A particular advantage of the process of the present invention is that the adhesive is not applied to the substrates as a powder, as a melt or as a solution hot. Such methods have been suggested in the prior art but are not convenient. In step A of the process of the present invention, a primer is applied to the first substrate (1). The ethylene or propylene polymer in the primer acts as a polymeric adhesive and has grafted thereto an unsaturated carboxylic acid or anhydride, ester, amide, imide or metal salt thereof, hereinafter referred to as graft". The grafting compound is preferably an unsaturated aliphatic dicarboxylic acid, or a thereadrido, ester, amide, imide or metal salt derived from said acid. The carboxylic acid preferably contains up to 6, more preferably up to 5 carbon atoms. The alkali metal salts are the preferred metal salts. Examples of unsaturated carboxylic acids are maieic acid, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, crotonic acid, and citraconic acid. Examples of unsaturated carboxylic acid derivatives are maleic anhydride, citraconic anhydride, itaconic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl acrylate, glycidyl methacrylate, maleate of monoethyl, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, diethyl itaconate, acrylamide, methacrylamide, mono-maleamide, dimaleamide, N. N-dietimaleamide, N-monobutylmaleamide, N, N-dibutylmaleamide, monofumaramide, difumaramide, N-monoethyl fumarate, N-monoethyl fumarate, N, N- Diethylfumaramide N-monobutylfumaramide, N, Nd? but? lfumaramide, maieimide N-butiimaiimide N-phenylamaiimide, soaioacrylate, sodium metacplate, potassium acutate, and potassium metacuplate Maleic anhydride is the preferred graft compound One or more , preferably a graft compound is grafted to the ethylene or propylene polymer. The content of the grafted compound in the ethylene or propylene polymer is preferably in the range of 005, more preferably 0-5, and even more preferably 08, preferably 15, more preferably at 10, and even more preferably at 2 weight percent, based on the total weight of the grafted ethylene or propylene polymer. The grafted ethylene or propylene polymer, as well as the ethylene or propylene polymer which is used for grafting, preferably has a density of up to 0902 g / cm3. However, it should be understood that the density of the polymer changes slightly when grafted. In the case of ethylene polymers, it has been found that the density of the polymer is important to provide a primer with sufficient strength and flexibility and to achieve a sufficient solubility of the ethylene polymer grafted into the organic solvent. For the term an ethylene polymer or propylene "means an ethylene polymer, a propylene polymer, a mixture of different ethylene polymers, a mixture of different propylene polymers, or a mixture of at least one ethylene polymer and at least one propylene polymer. The preferred polymers of ethylene and propylene polymers are described below. The ethylene or propylene polymer preferably has a density of 5 to 35 percent, more preferably 10 to 20 percent. The ethylene or propylene polymer can be an ethylene or propylene homopolymer or a propylene interpolymer and at least one α-olefin of C, -C2o and / or a C-18 diolefin. Preferably, the ethylene polymer is an interpolymer of ethylene and at least one C3-C20 olefin and / or a C4-C diolefin. Almost preferably, the ethylene polymer is an interpolymer of ethylene and an C3-C20 olefin having a density of up to 0.902 g / cm3. The term "interpolymer" as used herein, refers to polymers prepared by the polymerization of at least two different monomers. The generic term of etherpolymer, therefore, encompasses copolymers, usually used to refer to polymers prepared from two different monomers, and polymers prepared from more than two different monomers. The interpoiimer can be a random or block interpolymer. The preferred α-olefins contain from 4 to 10 carbon atoms, of which 1-butene, 1-hexene, 4-metii-1-pentene, and 1-octene are more preferred. The preferred diolefins are isoprene, butadiene, 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, dicyclopentadiene, methylene-norbornene, and -et? L? Deno-2-norborneno. The interpolymers may contain other comonomers, such as an acetylenically unsaturated monomer The primer more preferably contains a random or block copolymer of ethylene and a C4-C10 α-olefin, more preferably a copolymer of ethylene and 1-butene, 1-hexene, 4-methyl-1-pentene, or -octeno The ethylene content is preferably more than 50 percent, more preferably 60 to 90 percent, even more preferably 70 to 80 percent, based on the total weight of the polymer. The known ethylene polymers can be used for grafts, which preferably have a density within the scale mentioned above. A useful type of ethylene polymers is a linear copolymer of ethylene and an α-olefin having at least four carbon atoms, which have a narrow molecular weight distribution, a random distribution of comonomer units throughout the structure of the polymer base, and a homogeneity index of at least 75. Said polymers are described by Elston in the US Patent 3,645,992. Other useful polymers and a process for producing them are described in the U.S. Patent. 5,324,800. They have a weight average molecular weight, from 500 to 1,400,000, preferably from 1,000 to 500,000 and a molecular weight distribution Mp / Mn from 1.5 to 4.0. They are linear copolymers of ethylene and a C3-C20 α-olefin. Other are described linear polymers in the U.S. Patent. 4,429,079. They are random copolymers of ethylene and an α-olefin having from 3 to 10 carbon atoms which have a melt index of 0.1 to 50 g / 10 minutes, preferably 1 to 30 g / 10 minutes, a density of 0.870 to 0.900 g / cm3, preferably from 0.875 to 0.895 g / cm3, an X-ray crystallinity of 5 to 40 percent, preferably 60 ° C to 90 ° C, and an ethylene content of 85 to 95 mole percent. Ethylene polymers include those polymers available under the trademark TAFMER (Trademark of Mitsui Petrochemical) and EXACT (Trademark of Exxon Chemical), particularly those having a density of up to 0.902 g / cm3. The most preferred interpolymers of ethylene and at least one C3-C20 α-olefin and / or C4-Ci8 diolefin on which a graft compound mentioned above is grafted, are substantially linear ethylene polymers having: i) from 0.01 to 3 long chain branches per 1000 carbon atoms along the structure of the polymer base; ii) a melt flow ratio, I10 I25.63; iii) a molecular weight distribution, Mp / Mp, defined by the equation (Mp / Mn) (l10 / l2) -4.63, and iv) a critical shear stress at the beginning of the total fusion fracture greater than 4 x 106 dynes / cm2 or an effort regime critical to the principle of the surface fusion fracture of at least 50 percent more than the critical stress regime at the beginning of the surface melting fracture of a linear ethylene polymer having approximately the same melt index and Mp / The substantially linear ethylene polymers and methods for preparing them are described in greater detail in U.S. Patents 5,272,236 and 5,278,272. The substantially linear ethylene polymers have from 001, preferably from 005, to 3, and preferably to 1, branches per 1000. carbon atoms along the structure of the base of the polymers. The long chain branching is defined herein as a chain length of at least about 6 carbon atoms, over which the ionality can not be distinguished by carbon NMR spectroscopy. The long chain branch can be about as long as the polymer base structure For ethylene / α-olefin copolymers, it manifests as increased reogenic properties Useful techniques are known for determining the presence of long chain branches in ethylene polymers, including ethylene / 1-octene codend . Two of these methods are gel permeation chromatography with a laser angle scanner at a lower angle (CPG-BLLAI) and gel permeation chromatography coupled with a viscometer detector. differential (CPG-VD). The use of these techniques for detection of long chain branching and fundamental theories, have been documented in the literature. Refer to Zimm, G.H and Stockmayer, W H. j. Chem. Phys., 17 1301 (1949) and Rudin, A., Modern Methods of Polymer Charactepzation, John Wiley & Sons, New York (1991) pages. 103-112. In contrast to the term "substantially linear", the term "iineai" means that the polymer lacks measurable or demonstrable long chain branches, that is, the polymer is substituted with an average of less than 0.01 long branches / 1000 carbons. Melt index "o 'i2" means the melt index measured in accordance with ASTM D-1238, Condition at 190 ° C / 2.16 kg. "I10" is measured in accordance with ASTM D-1238, Condition at 190 ° C / 10 kg. The melt index 12 of the substantially linear ethylene polymer is generally 0.01 g / 10 minutes at 1000 g / 10 minutes, preferably 0.01 g / 10 minutes at 100 g / 10 minutes. The melt flow index ratio, ie, h0 / l2, is at least 5.63, preferably at least 6, more preferably at least 7, and is essentially independent of the poiidispersity index, in contrast to the polyethylenes showing a dependence of the melt flow index on the index of po dispersity. This property is illustrated in Figure 2 of the US Patent. 5,272,236.

The polydispersity index of the substantially linear ethylene polymers (ie, the molecular weight distribution, or the ratio to the weight average molecular weight, to the number average molecular weight (Mp / Mn)), determined by permeation chromatography of gel defined by the equation: (Mp / Mn) (l? 0 / l2) -4.63. The polydispersity index is preferably less than 3.5, more preferably from 1.5 to 2.5. in addition, substantially linear ethylene polymers, specifically substantially linear ethylene polymers, have a critical shear stress at the beginning of the total melt fracture, determined by gas extrusion rheometry, greater than 4x106 dynes / cm3, or an extrusion rheology of gas in such a way that the critical shear rate at the beginning of the surface melt fracture for the substantially linear ethylene polymer is at least 50 percent greater than the critical shear rate at the beginning of the melt fracture of surface for a linear ethylene polymer, wherein the substantially linear ethylene polymer and the linear ethylene polymer comprise the same comonomer or comonomers, the linear ethylene polymer has a 12, Mp / Mn and density within 10 percent of values corresponding to the substantially linear ethylene polymer and where the stress regimes The respective critical cutting edges of the substantially linear ethylene polymer and the linear ethylene polymer are measured at the same melting temperature using a gas extrusion rheometer.

The determination of the critical shear rate regime and the critical shear stress with respect to the melt fracture as well as other rheology properties is carried out using a gas extrusion reomeiro (REG). The gas extrusion meter is described by M. Shida. R.N. Shroff and L.V. Cancio in Polymer Enqineepng Science, Vol. 17, No. 11, p. 770 (1977), and in "Rheometers for Molten Plastics1" by John Dealy, published by Van Nostrand Reinhoid Co. (1982) on pages 97-99.The substantially linear ethylene polymer has a single melting peak by calorimetry. Differential sweep, CBD, between -30 ° C and 150 ° C. The only melting peak, can show, depending on the sensitivity of the equipment, a "shoulder" or a "pump" in the low melting period that constitutes less than 12 percent, usually less than 9 percent, and more usually less than 6 percent, of the total melting heat of the polymer The methods for grafting a graft compound mentioned above onto a non-grafted ethylene or propylene polymer described above, are generally known and described in the art, for example, in the Patents of E.U.A. 4,739,017 and 4,762,890. The primer used in the process of the present invention comprises (A) one or more of the grafted ethylene or propylene polymers described above, and (B) an organic solvent, wherein the total amount of the grafted ethylene polymer and / or polymer (s) of propylene, is at least 1 percent, based on the total weight of (A) and (B). Preferably, the primer comprises 2 per percent, more preferably 3 percent, and preferably up to 30 percent, more preferably up to 20 percent, and even more preferably up to 10 percent of the grafted ethylene polymer and / or propylene polymer (A), based on the total weight of (A) and (B). Examples of organic solvents that are useful in the primer are aromatic hydrocarbons, such as benzene, toluene, or xylene; aromatic hydrocarbons such as hexane, heptane, octane, or decane; cyclic hydrocarbons, such as cyclohexane or methyl cycloheptane, medium hydrogen bonding solvents, such as methyl ethyl ketone, tetrahydrofuran or tertiary butanol; or chlorinated hydrocarbons, such as trichlorethylene, perchlorethylene, dichloroethylene, dichloroethane, or chlorobenzene. Aromatic hydrocarbons, particularly, are alkyl-substituted aromatic hydrocarbons. The primer may contain a mixture of organic solvents. The combined weight of grafted ethylene and / or propylene polymer (s) (A) and the organic solvent (s) (B) is at least 80 percent, more preferably, of at least 90 percent, still more preferably at least 95 percent, based on the total weight of the primer. More preferably, the primer consists substantially of ethylene and / or propylene polymer (s) (A) and the organic solvent (s) (B). The primer used in the process of the present invention may contain one or more other components, such as a additional adhesive a tackifying resin, a stabilizer, for example, a known UV stabilizer or heat stabilizer, and / or one or more of the non-grafted ethylene and / or propylene polymers, such as those described above. A tackifying resin is usually an aliphatic resin, a polyterpene resin, a hydrogenated resin, or a mixed aliphatic aromatic resin. Examples of tackifying resin include those available under the trademark "ESCOR EZ" (Exxon Chemical Co.), "PICCOTAC", "PICCOVAR", "PICCOLYTE" (Hercules, Inc.), "WI NGTACK" (Goodyear) and "ZONAR EZ" (Arizona). If the primer used in the process of the present invention contains an additional adhesive, its amount is preferably up to 15 percent, more preferably from 0.3 to 10 percent, even more preferably from 1 to 5 percent based on the total weight of the primer The adhesive can be, for example, a 1 or 2 part adhesive. Examples of suitable adhesives include epoxy resins, urethanes, latexes, acrylates, elastomer-solvent cements, gums, and polysilicones. A preferred additional adhesive is a di- or tri-isocyanate compound or prepolymer, such as tris (4-isocyanatophenyl) thiophosphate, toluene di-isocyanate, methylene-di-p-phenylene isocyanate, or urethane polymers of the same. Examples of available polyisocyanate compounds or prepolymers include "VKFE" (manufactured by Fratelli Zucchini s rl) "DESMODUR ™ RF-E" (Trademark of Miles Inc.), "MDI" polymeric of "PAPI ™" (Trademark of The Dow Chemical Company) and "UPACO 3570" (Manufactured by Orthen Industries, UPACO Division). The inclusion of a tackifying resin or an additional adhesive in the primer is, for example, advantageous if the first substrate (I) comprises a synthetic resin, such as PVC (synthetic leather) or synthetic fibers, such as pohamide or polyester. If the second substrate (I) comprises piei naturai or natural fibers, such as cotton or jute fibers, the grafted ethylene or propylene polymer described above is preferably the only adhesive comprised in the primer. The primer is prepared by mixing the grafted ethylene or propylene polymer or a mixture thereof and optional additives with the organic solvent (s), preferably at a temperature of 10 ° C to 150 ° C, more preferably from 20 ° C to 100 ° C, in order to dissolve the grafted ethylene or propylene polymer. It may be useful to stir the mixture, for example, stirring the mixture for 30 to 90 minutes. At least, the preferred grafted interpolymers described above for ethylene and at least one C3-C20 α-olefin and / or C4-C? Dio diolefin having a density of up to 0.902 g / cm °, are sufficiently soluble in an organic solvent, so that they can remain dissolved, even when the temperature of the primer is reduced to room temperature or to a slightly elevated temperature. This is very advantageous because It is not necessary to keep the hot primer hot and apply it to the substrate. In step A of the process of the present invention, the primer can be applied to the first substrate (I) in a convenient manner, for example, by means of brushing, immersion techniques. or spray The primer preferably has a temperature of less than 80 ° C, more preferably 10 ° C to 80 ° C, still more preferably 15 ° C to 60 ° C when applied to the first substrate (I) When the concentration of the polymer of ethylene or propylene grafted onto the primer is superior, and consequently, the viscosity of the primer as high, it may be useful to apply the primer to the substrate (I) at a higher temperature. The first substrate (I) may comprise or consist substantially of a broad a variety of materials, particularly polar materials, for example, a metal, such as aluminum, iron, brass, or galvanized iron, an inorganic material, such as glass, cement, or asbestos, or a natural material such as wood However, the preferred materials are synthetic or natural rubbers, synthetic skins, such as PFC, natural skins such as buckskin, hemp, buff, or skin, materials made of fibers natural, such as cotton or other cellulosic material, linen or jute, or materials made of synthetic resins or synthetic fibers, such as polyamides, preferably nylon 6, nylon 10, nylon 11, nylon 12, nylon 66, or nylon 610, such polyethers such as polyethylene terephthalates, or polybutylene terephthalates, polyurethane polycarbonates, saponification products of an ethylene / vinyl acetate copolymer, epoxy resins, vinyl chloride resins, vinylidene chloride resins, poly (methyl methacrylate), or mixtures thereof. The first substrate (I) may consist of one or more layers and each layer may consist of one or more materials. The amount of primer applied to the first substrate is generally 1 to 100 g / m.sup.-1 of the surface of the first substrate, preferably from 10 to 90 g / m2, more preferably from 30 to 80 g / m2. Usually, one of the surfaces is at least partially coated with the primer. After the coating, a portion of the total amount of the solvent that is comprised in the primer may be evaporated, although it is generally not necessary to dry the primed substrate (I). Before the above-described primer (I) is applied to the primer described above, an additional tackifier or tackifier described above can be applied to the first pure substrate or dissolved in a solvent. However, preferably as the primer described above is applied to the first substrate (I) before the second substrate (II) is injection molded into the first substrate. This means that the primer described above is preferably the only adhesive that is applied to the first substrate (i) to join the two substrates. In step B of the process of the present invention, an ethylene or propylene polymer and optional additives are injection molded into the first primed substrate (I). Therefore, the second substrate (II) is formed on the first primed substrate (i) By the term "an ethylene or propylene polymer" is meant an ethylene polymer, a propylene polymer. a mixture of different ethylene polymers, a mixture of different propylene polymers. or a mixture of at least one polymer of ethylene and at least one propiylene polymer. Illustrative of itself, are polypropylenes, low density, branched polyethylene with a density of 0.915 to 0.940 g / cmJ, high density polyethylene of a density of 0940 to 0.960 g / cm0, linear low density polyethylene (LLDPE) or polyethylene. of very low density (PEMBD) of a density of 0.900 to 0.915 g / cm ° or mixtures thereof. These polymers are known in the art. The ungrafted ethylene or propylene polymer density is preferably up to 0 902 g / cm 3, but it can also be superior. The density of the ethylene or propylene in the second substrate (II) is generally from 0.850 to 0.960 g / cm °, more preferably from 0.850 to 0.902 g / cm3, still more preferably from 0.869 to 0.890 g / cm3. The preferred ethylene and propylene polymers are those which have been described above as a starting material for preparing the ethylene and propylene grafted in the primer. The most preferred ethylene polymers are those described in US Patents. 3,645,992; 5,324,800; 4,429,079; and 5,272,236 previous. The most preferred ethylene polymers are the substantially linear ethylene polymers that were described above in greater detail.

Z The ethylene or propylene polymer can be mixed with one or more optional additives, such as heat stabilizers, climate stabilizers, antistatic agents, nucleating agents, fillers, pigments, dyes, fire retardants, blowing agents, antiblocking agents , and / or oils, such as paraffinic oil or naphthenic oil In addition to one or more polymers of ethylene or propylene, the second substrate may contain one or more other polymers, such as styrene biocide copolymers, PFC, chlorinated polyethylene, EVA , chloroprene, ethylene-propylene rubbers, EPDM rubbers. natural rubbers, thermoplastic polyurethanes, or polyolefins grafted with silane. However, the amount of the ethylene or propylene copolymer (s) is preferably at least 40 percent, more preferably at least 50 percent, even more preferably at least 70 percent, based on the total weight of the second substrate. More preferably, the second substrate consists substantially of one or more polymers of ethylene or propylene. In the process of the present invention, step B is preferably carried out as follows. A primed substrate (i) is placed in a mold of an injection molding machine, so that the primed surface faces toward the injection point (s). The ethylene or propylene polymer and optional additives are heated to a temperature sufficient to plasticize the poiimer (s), preferably at a temperature of 80 ° C to 350 ° C, more preferably from 100 ° C to 250 ° C, even more preferably from 120 ° C to 180 ° C. The molding temperature in general is from 0 ° C to 8UUC, more preferably from 5 ° C to 40 ° C. The ethylene polymer or propylene and optional additives are allowed to solidify, whereby the second substrate (II) is formed on the primed substrate (I). This step generally takes from 5 to 300 seconds, preferably from 15 to 120 seconds. Suitable machines are known in the art. injection molding The second substrate (II) preferably has a thickness of 1 mm to 30 cm, more preferably 4 mm to 5 cm The second substrate (II) may be compact or fluffy, depending on the types of additives mixed with the ethylene or propylene polymer before injection molding The laminate produced can then be used as tai or subjected to additional operations, such as cutting into pieces of the desired size, painting, scoring or varnishing. The laminate produced in accordance with The process of the present invention is useful for a variety of applications, including bathroom scales, carpet reinforcement, fabric reinforcement for automotive interior finishes, and preferably, for footwear, such as shoes. In said footwear, the second substrate (II ), which comprises an ethylene or propylene polymer, forms the sole of the shoe, while the first substrate (I) forms the upper part of the shoe. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention. invention Unless to be stated otherwise, all parts and percentages are given weight Example 1 To prepare the primer, a substantially linear ethylene polymer having a density of 0.870 g / cm ° and a melt index of 5.0 g / 10 was used. minutes, which is commercially available from DuPont Dow Elastomers LLC as ethylene-1-octene copolymer ENGAGE ™ EG 8200. "0.95 weight percent of the malt anhydride in the substantially linear ethylene polymer has been grafted in. To prepare the primer, 90 parts of toluene and 10 parts of the substantially grafted linear polymer It was heated for 1 hour under reflux.The primer was allowed to cool to room temperature and then applied to skin strips of 17.5 cm x 2.5 cm x 0.12 cm that were previously treated in accordance with DIN 53273 Treatment in accordance with DIN 53273 involved scalp the skin with moderate fat content (from 0 to 10 percent by weight) to remove the grain layer, scraping it with P40 abrasive paper and removing any debris with a soft brush. 50 g of primer was applied per square meter of pomace strips using a brush. The primed skin was allowed to dry for 23 minutes at 23 ° C. The primed and dried strips were then placed in a 170 mm x 170 mm x 4 mm mold of an "ENGEL ™ 80" injection molding machine. A composition consisting of 30 parts of polyolefin elastomer "Engage ™ EG8150" (available from DuPont Dow Elastomers L.L.C), 14 parts of Affinity polyolefin plastomer "PF1140 (available from The Dow Chemical Company), both being ethylene-octene copolymers, 23 parts calcium carbonate filler, 30 parts Shellflex oil" 371 available from Shell and 3 parts high density polyethylene IP90, available from The Dow Chemical Company, were injection molded into the skin strips. The temperatures in the four cylinders were 160 ° C, 160 ° C, 160 ° C and 150 ° C, respectively. The temperature of the mold was 35 ° C. The injection pressure was 80 bar (8,000 kPa), the screw stroke 68 mm, the cooling time 40 seconds and the injection speed 80-80-80-80-80-80-80-40-30 mm / s . The adhesion between the skin and the substrate made of ethylene / 1-octene copolymer was measured in accordance with DIN 53273 L (3D). The detachment force was 6.0 N / mm. Comparative Example A Example 1 was repeated, except that no primer was applied to the skin strips before the ethylene / 1-octene copolymer was injection molded into the skin strips. The peel force between the skin and the substrate made of ethylene / 1-octene copolymer was only 0.9 N / mm. Comparative Example B The primer of Example 1 was applied to a skin strip and dried as in Example 1. An 8 cm x 2.5 cm x 0.2 cm sheet was prepared from the same composition as used in Example 1 for injection molding. 50 g of the primer of Example 1 was applied per square meter of polymer sheet. The sheet of Or primed polymer, allowed to dry for 30 minutes at 23 ° C. The primed polymer sheet was then heated to 80 ° C and pressed onto the primed skin strip at a pressure of 4 bar. The detachment force between the substrate and the substrate made of ethylene / 1-ketene copolymer. it was only 1.8 N / mm. Comparative Example C 5 parts of a substantially linear ethylene polymer having a density of 0.902 g / cm ° and a melt index of 1.og / 10 minutes which is commercially available from The Dow Chemical Company as AFFINITY PL 1880 ™ "and toluene portions were heated as described in Example 1. The substantially iineai ethylene polymer was not grafted with the maieic anhydride.A nebulous dispersion was produced.When standing still at 19 ° C, the polymer was precipitated from The dispersion Comparative Example D 5 parts of propylene copolymer having a density of 0.902 g / cmJ which is commercially available from Union Carbide as "CEFOR DS4D25L" and 95 parts of toluene, were heated as described in Example 1. Ei Propylene polymer was not grafted with maieic anhydride, no homogeneous solution was observed but a gel structure.The dispersion and gel prepared according to Comparative Examples C and D, did not they were very suitable as a primer in the process of the present invention. Examples 2 to 7 A 7.5 percent solution of the same substantially linear ethylene polymer grafted with maleic anhydride, as used in Example 1, was prepared by heating under reflux for one hour the polymer grafted with maleic anhydride in a mixture of solvents to give a final composition of 20 percent tertiary butanol. 9.5 percent toluene and 63 percent cyclohexane. In Examples 2, 4 and 6, the solution produced was used as such, as a primer. In Examples 3, 5 and 7, 5 percent of an isocyanate compound "VKFE", commercially available from Fratelli Zucchini s.r.l., was added after the solution had cooled to room temperature. As described in Example 1, the primer was then applied, using a cepiyl, onto the synthetic nylon woven teia test strips. PET and synthetic leather P-PVC. Before applying the primer, the strips were roughened with P40 abrasive paper, cleaned with 1, 1, 2,2-tetrachloroethane and methyl ethyl ketone, respectively. The coated strips were then used in an injection molding process and tested as described in Example 1.

Examples 8 and 9 A 5 percent solution of the same maleic anhydride-grafted polymer as in Example 1. was prepared by heating under reflux for one hour the maleic anhydride-grafted polymer in a mixture of solvents to give a final composition of 1 per one hundred methyl ethyl ketone, 10 percent toluene, and 67 percent cyclohexane. In Example 8. the solution produced was used as a primer. In Example 9, 5 percent of the isocyanate compound VKFE, commercially available from Fratelh Zucchini s r.l., was added after the solution had cooled to room temperature. As described in Example 1, the primer was then applied, using a brush, on the high-fat skin test strips (15 to 16 percent). The coated strips were then used in an injection molding process and the tested stripping and stripping tested as described in Example 1. % solution 5.5! Solution 5% + VKFE 58 O The aging properties of the adhesive bond are important for high-fat skins where the adhesive properties can be reduced due to adhesive attack by grease. The results of the drag test according to DIN 53273 after aging, They are the following: Examples 10 and 11 A 2.5 percent solution of the same maleic anhydride-grafted polymer as in Example 1 was prepared by heating under reflux for one hour the polymer grafted with maleic anhydride in toluene. In Example 10, the solution was used as tai as a primer. In Example 11, 5 percent of the commercially available isocyanate compound of VKFE was added from Fratelli Zucchini s r.l., after cooling the solution to room temperature. As described in Example 1, this primer was then applied, using a brush, to skin test strips with moderate fat content, the coated strips were used in a moideo process by injection and tested as described in FIG. Example 1

Claims (5)

1. CLAIMING IS 1. A process for preparing a laminate comprising a first substrate (I) and a second substrate (II), which comprises an ethylene or propylene polymer and which is bonded to the first substrate by means of a polymeric adhesive, wherein the process comprises the steps of: A) applying to the first substrate (I) a primer comprising an organic solvent and an ethylene or propylene polymer by having a carboxylic acid or an anhydride, ester, amide, imide or metal salt thereof grafted thereto; combined weights of the grafted ethylene or propylene polymer and the organic solvent is at least 80% based on the total weight of the primer, and B) injection molding an ethylene or propylene polymer and optional additives on the primed substrate (I) .
2. 2. The process of claim 1, wherein the primer comprises an interpolymer of ethylene and at least one C3-C20 α-olefin and / or a C4-C? Dio diolefin, having a density up to 0.902. g / cm3.
3. 3. The process of claim 1 or 2, wherein the primer is applied to the first substrate (I) at a temperature of less than 80 ° C.
4. 4. The process of any of claims 1 to 3, wherein the amount of grafted unsaturated carboxylic acid, anhydride, ester, amide, imide or metal salt thereof, is from 0.05 to 15 percent, based on the total weight of the grafted ethylene or propylene polymer.
5. 5. The process of any of claims 1 to 4, wherein the second substrate (II) comprises a homogen of ethylene or propylene, an interpoemmer of propylene and at least one α-olefin of C4-C2o and / or a diolefin of C -C? 8, or an ethylene interpolymer and at least one C3-C2o α-oiefin and / or a C4-C? s diolefin, or a combination thereof. 6 The process of any of claims 1 to 5, wherein the second substrate (II) comprises an ethylene polymer of a density of up to 0.902 g / cmJ. 7. The process of claim 2 or claim 5, wherein the interpolymer of ethylene and at least one C3-C20 α-olefin and / or a C -C? Dio diolefin is an ethylene polymer substantially free of charge. iineai having: i) from 0.01 to 3 long chain branches per 1000 carbon atoms along the structure of the polymer base; II) a melting flow ratio, h0 / l2 5.63; iii) a molecular weight distribution, Mp / Mn, defined by the equation: (Mp / M ") (h0 / l2) -4.63, and iv) a critical shear stress at the beginning of the total fusion fracture greater than 4 x 10 ° dynes / cm2 or a critical stress regime at the beginning of the surface fusion fracture of at least 50 percent more than the critical stress regime at the beginning of the surface melt fracture of a polymer linear ethylene having approximately the same melting index and Mp / Mn. The process of any of claims 1 to 7, wherein the primer additionally contains an isocyanate compound or prepolymer. The process of any of claims 1 to 8, wherein the first substrate (1) comprises a synthetic and / or natural resin, rubber, skin and / or fibers. 10. A laminate produced according to the process of any of claims 1 to 9. 11. Footwear produced according to the process of any of claims 1 to 9. RESU EN A process for preparing a laminate comprising a first substrate (l) and a second substrate (II), which comprises an ethylene or propylene polymer and which is bonded to the first substrate by means of a polymecop adhesive, wherein the The process comprises the steps of: A) applying to the first substrate (I) a primer comprising an organic solvent and an ethylene or propylene polymer by having a carboxylic acid or an ahnidpdo, ester, amide, imide or metal salt thereof grafted thereto. , and B) injection molding an ethylene or propylene polymer and optional additives on the primed substrate (I).