MXPA06001913A - Impact-modified polyamide film - Google Patents

Abstract

Films made from impact-modified polyamide.

Description

MODIFIED IMPACT POLYAMIDE FILM FIELD OF THE INVENTION The invention concerns films made of modified impact polyamide. The films according to the invention comprise, as a single layer, (1) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and, optionally, (2) at least one layer L2 comprising an aliphatic polyamide. Additional advantages and other aspects of the present invention will be set forth partially in the description that follows and will be partially obvious to those having experience in the art of examining what follows or can be learned from the practice of the present invention. The advantages of the present invention can be realized and obtained as indicated in the appended claims. As will be realized the present invention is capable of other and different modalities, and its various details are capable of modifications in several obvious aspects, all without departing from the present invention. The description is to be considered as illustrative in nature, and not restrictive.

BACKGROUND OF THE INVENTION Polyamide films, such as PA 6, 66, 11, 12 and others are known and used in a variety of applications. For example, polyamide films are used to provide protective properties against chemicals, water and fuel or as insulating components in electrical applications. However, there remains a need to improve the performance of polyamide films with respect to, for example, their mechanical properties, resistance to water, other solvents and chemicals, electrical insulation properties, etc.

SUMMARY OF THE INVENTION The present invention provides a film comprising as a single layer, (l) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and optionally, (2) at least one layer L2 comprising a polyamide aromatic In a preferred embodiment, Ll is the single layer of the film. In another preferred embodiment, the layers Ll and L2 are in direct contact with each other and are the unique layers included in the film. In a further preferred embodiment the film includes as single layers, three contiguous layers, in the order L1 / L2 / L1. In yet a further preferred embodiment the film includes as single layers, two or more contiguous Ll layers. In a further preferred embodiment the film includes as single layers, any number of contiguous layers of the order [(Ll) n / (L2) m] x, where x is any integer of 1 or greater, n is any integer of 1 or greater and m is any integer (for example 0, 1, 2, etc.). In another preferred embodiment, the film does not contain a fluoropolymer layer, where the film of the invention is a multilayer construction, each of the layers Ll and L2 may be the same or different from each other. The films of the invention can be made in any desired way from the materials identified to produce the layers Ll and L2, such as by extrusion, such techniques are well known to those skilled in the art. The size, shape, thickness, texture of the surface, etc. of the films of the invention are not limited in any way.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an illustration of an extrusion fit for extruding films according to the invention.

DETAILED DESCRIPTION OF THE INVENTION For the multilayer construction of three or more layers, the term "inner layer" means the most intimate layer of the film. The term "outer layer" means the outermost layer of the film; that is, there are no other layers of the film immediately adjacent to and external to the outer layers. The multilayer film constructions have two outer layers. Where the film is constituted by an individual layer, it is called "monolayer". Polyamides Polyamides are, generally speaking, polymers containing a repeating amide functionality (CONH). Typically, the polyamides are formed by reacting the diacid and diamine monomer units (eg, nylon 6,6), or by polymerization of an amino carboxylic acid or caprolactam (eg, nylon 6). Polyamides are well-known materials. Polyamides which are useful herein include those described in U.S. Pat. 6,531,529, 6,359,055, ,665,815, 5,436,294, 5,447,980, RE34,447, 6,524,671 (DuPont), 6,306,951 (BP Corp.) and 5,416,189 as well as those marketed by Solvay Advanced Polymers under the trade names Amodel® and IXEF®. The invention concerns both aromatic and aliphatic polyamides. The aromaticity of the aromatic recurring units may be due to the diacid and / or the diamine for the polyamides resulting from the polycondensation. Ll Composition of Polyamide L-polyamide compositions for films useful herein comprise an aromatic polyamide and an impact modifier. Aromatic Polyamide Aromatic polyamides are polymers comprising more than 50 mole% of "Type 1" repeating units, based on 100 mole% repeat units in the polymer. Type 1 repetition units have at least one CONH group in the polymer chain. In addition, Type 1 repeat units are characterized in that at least 30 mole% thereof comprises an aromatic group. Accordingly, the minimum content of repeating units containing aromatic group in an aromatic polyamide herein is more than 15 mol% based on 100 mol% repeat units in the polymer. Preferably the aromatic polyamide of the invention comprises at least 20 mol% based on 100 mol% of monomers forming the polyamide, of monomers comprising an aromatic group. Although not required, such aromatic groups typically originate from a diacid monomer, and include terephthalic acid, isophthalic acid, phthalic acid (1,2-benzenecarboxylic acid), etc. In preferred embodiments, the aromatic polyamide comprises at least 30 mol%, based on 100 mol% of monomers forming the polyamide, of monomers comprising an aromatic group, including 35, 40, 45, 50, 55, 60, 65, 70 , 75, 80, 85, etc% molar. One class of preferred aromatic polyamides are PMXDAs, ie aromatic polyamides comprising more than 50 mol% of recurring units formed by the polycondensation reaction between at least one aliphatic diacid and metaxylylylene ina. The aliphatic diacid may be particularly adipic acid. Suitable PMXDAs are particularly available as IXEF® PMXDAs from Solvay Advanced Polymers. Another class of preferred aromatic polyamides are polyphthalamides, ie aromatic polyamides comprising more than 50 mol% of recurring units formed by the polycondensation reaction between at least one of phthalic acid and at least one aliphatic diamine.

The aliphatic diamine can be, in particular, hexamethylenediamine, nonanodiamine, 2-methyl-1, 5-pentadia ina, and 1,4-diaminobutane. Suitable polyphthalamides are particularly available as AMODEL® polyphthalamides from Solvay Advanced Polymers, LLC. Among the polyphthalamides, polyterephthalates are preferred. Polyterephthalates are defined as aromatic polyamides comprising more than 50 mol% of recurring units formed by the polycondensation reaction between terephthalic acid and at least one diamine. A group of preferred polyterephthalamides are polyterephthalamides consisting essentially of recurring units formed by the polycondensation reaction between terephthalic acid and at least one aliphatic diamine. In the polyterephthalamides of this group, the aliphatic diamine preferably comprises from 3 to 9 carbon atoms, and most preferably, comprises 6 carbon atoms. An example of aliphatic diamine comprising 6 carbon atoms is hexamethylenediamine. A second group of preferred polyterephthalamides are polyterephthalamides consisting essentially of recurring units formed by the polycondensation reaction between terephthalic acid, isophthalic acid and at least one aliphatic diamine. In this embodiment, the molar ratio of terephthalic acid and isophthalic acid can be from 50 to 80 (including 55, 60, 65, 70, and 75) for terephthalic acid and from 10 to 40 (including 15, 20, 25, and 35) for isophthalic acid. In another embodiment, the molar ratio can be from 35 to 65 for terephthalic acid and no more than 20 for isophthalic acid. A third group of preferred polyterephthalamides are polyterephthalamides consisting essentially of recurring units formed by the polycondensation reaction between terephthalic acid, at least one aliphatic diacid and at least one aliphatic diamine. In this embodiment, the molar ratio of the terephthalic acid and the aliphatic diacid can be from 50 to 80 (including 55, 60, 65, 70, and 75) for the terephthalic acid and not more than 25 (including 5, 10, 15, and 20) for the aliphatic diacid. In another embodiment, the molar ratio can be from 35 to 65 for terephthalic acid and from 30 to 60 for the aliphatic diacid. A fourth group of preferred polyterephthalamides are polyterephthalamides consisting essentially of recurring units formed by the polycondensation reaction between terephthalic acid, isophthalic acid, at least one aliphatic diacid and at least one aliphatic diamine. In this embodiment, the molar ratio of terephthalic acid and terephthalic diacid can be from 50 to 80 (including 55, 60, 65, 70 and 75) for terephthalic acid; from 10 to 40 (including 15, 20, 25, and 35) for isophthalic acid; and no more than 25 (including 5, 10, 15, and 20) for the aliphatic diacid. In another embodiment, the molar ratio can be from 35 to 65 for terephthalic acid; not more than 20 for isophthalic acid; and from 30 to 60 for the aliphatic diacid. Another preferred aromatic polyamide useful herein is one made from terephthalic acid, adipic acid, optionally isophthalic acid, and hexamethylene diamine. In another preferred embodiment the aromatic polyamide is a polyamide with at least 50 mol%, including up to 100 mol% of recurring units obtained by means of the polycondensation reaction between terephthalic, isophthalic, adipic acid; and at least one diamine, preferably an aliphatic. In this group, the molar ratio of terephthalic / isophthalic / adipic acid can be from 50 to 80 / from 10 to 40 / not more than 25. In another embodiment the molar ratio of terephthalic / isophthalic / adipic acid can be from 35 to 65 / not more than 20 / from 30 to 60. In preferred embodiments the diamine component for these acid mixtures is HMDA. In certain embodiments of the present invention, the dicarboxylic acid component used in the formation of the polyphthalamide comprises a molar ratio of aromatic dicarboxylic groups in the range from at least about 50 mol% aromatic groups to about 100% aromatic groups. In a preferred embodiment of the present invention, the polyphthalamide polymer comprises from about 50 mol% to about 95 mol% of hexamethylene terephthalamide units, from about 25 mol% to about 0 mol% of hexamethylene isophthalamide units, and from about 50 mol% to about 5 mol% hexamethylene adipamide units. Another useful aromatic polyamide is one made from terephthalic acid, isophthalic acid and an aliphatic amine such as HMDA, for example, using a ratio of 70/30 TA / IA. Particularly suitable polyphthalamides for use in the present invention are available as AMODEL® A-1000, A-4000, A-5000, and A-6000 polyphthalamides from Solvay Advanced Polymers, LLC. Suitable polyphthalamides for use in the present invention are described in the aforementioned U.S. Patents. Nos. 5,436,294; 5,447,980; and RE34,447 of Poppe et al. Of course, more than one aromatic polyamide can be used in the polyamide Ll composition. Impact Modifier The impact modifiers useful herein are not particularly limited in imparting useful properties to the aromatic polyamide component of the Ll layer of the invention, such as sufficient tensile elongation to deformation and rupture. For example, any low modulus of elasticity functionalized polyolefin impact modifier with a vitreous transition temperature of less than 0 ° C is suitable for this invention, including the functionalized impact modifiers described in U.S. 5,436,294 and 5,447,980. Useful impact modifiers include polyolefins, preferably functionalized polyolefins, and especially elastomers such as SEBS and EPDM.

Useful functionalized polyolefin impact modifiers are available from commercial sources, including alloyed polypropylenes and ethylene-propylene copolymers available as EXXELOR ™ PO and ethylene-propylene copolymer elastomer functionalized with maleic anhydride comprising about 0.6 weight percent of suspended succinic anhydride groups, such as EXXELOR® RTM. VA 1801 from the Exxon Mobil Chemical Company; acrylate modified polyethylenes available as SURLYN®, such as SÜRLYN® 9920, methacrylic acid modified polyethylene from the DuPont Company; and PRIMACOR®, such as PRIMACOR® 1410 XT, polyethylene modified with acrylic acid, from the Dow Chemical Company; styrene-ethylene-butylene-styrene block copolymer (SEBS) modified with maleic anhydride, such as KRATON® FG 1901X, an SEBS that has been grafted with about 2% by weight of maleic anhydride, available from Kraton Polymers; terpolymer elastomer of ethylene-propylene-diene monomers (EPDM) functionalized with maleic anhydride, such as ROYALTUF® 498, an EPDM functionalized with 1% maleic anhydride, available from Crompton Corporation. The films of the present invention are not limited to only those formed with these impact modifiers. Suitable functional groups in impact modifiers include any chemical portion that can react with end groups of the polyamide to provide improved adhesion to the die at high temperatures.

Other functionalized impact modifiers that can also be used in the practice of the present invention include higher ethylene-alpha-olefin polymers and higher ethylene-alpha olefin-diene polymers that have been provided with reactive functionality by grafting or copolymerized with carboxylic acids suitable reagents or their derivatives such as, for example, acrylic acid, methacrylic acid, maleic anhydride or their esters, and will have a tensile modulus up to about 50,000 psi determined in accordance with ASTM D-638. Suitable higher alpha-olefins include alpha olefins from C3 to Cs such as, for example, propylene, butene-1, hexene-1 and styrene. Alternatively, copolymers having structures comprising said units can also be obtained by hydrogenation of suitable homopolymers and copolymers of polymerized 1-3-diene monomers. For example, polybutadienes having varying levels of suspended vinyl units are readily obtained, and these can be hydrogenated to provide ethylene-butene copolymer structures. Similarly, the hydrogenation of polyisoprenes can be employed to provide equivalent ethylene-isobutylene copolymers. The functionalized polyolefins that can be used in the present invention include those having a melt index in the range of about 0.5 to about 200 g / 10 min. Suitable dienes for use in the preparation of ethylene-alpha-olefin-diene terpolymers are non-conjugated dienes having 4 to about 24 carbon atoms, examples of which include 1,4-hexadiene, dicyclopentadiene and alkylidene norbornenes such as -ethylidene 2- norbornene. Molar fractions of ethylene units and higher alpha-olefin units in the ethylene-alpha-olefin-olefin copolymer elastomers generally range from about 40:60 to about 95: 5. Ethylene-propylene copolymers having about 50 to about 85 mole percent of ethylene units and about 5 to about 50 mole percent of propylene units are included among these. In terpolymers comprising polymerized diene monomers, the content of diene units may vary up to about 10 mol%, and about 1 to about 5 mol% in certain embodiments. Also suitable are corresponding block copolymers comprising two or more polymeric blocks, each formed of one or more monomers selected from ethylene and the higher alpha-olefin. The functionalized polyolefins will generally further comprise about 0.1 to 10% by weight of functional groups. Other impact modifiers useful herein include those described in U.S. 6,765,062 (Ciba Specialty Chemicals Corporation) and EP 901 507 Bl (DuPont). Still other impact modifiers useful herein include acrylic impact modifiers marketed as Impact Modifiers Paraloid® by Rohm & Haas. The amount of impact modifier present in the composition Ll is not limited to and preferably will be an amount sufficient to impart sufficient tensile elongation to the deformation and rupture. Generally, the polyamide composition Ll will comprise from about 2% by weight to about 40% by weight of impact modifier, based on the total weight of the composition Ll, including for example 5, 10, 15, 20, 25, 30 and 35% by weight. However, the impact modifier may be present in such small amounts as, for example, 0.1% by weight.

The impact modifier and the aromatic polyamide can be mixed together in any manner, and the mixing can take place before, for example, extrusion, or the material can be mixed in the extruder. Of course, more than one impact modifier can be used in the polyamide composition Ll. Composition of Polyamide L2 The composition of polyamide L2 useful in the present optical layers of the film of the invention and comprises an aliphatic polyamide. Aliphatic polyamides are polymers comprising more than 50 mol% of "Type 2" repeating units, based on 100 mole% repeat units in the polymer. Type 2 repeat units have at least one CONH group in the polymer chain. In addition, Type 2 repeat units are characterized in that less than 30 mole% thereof comprise an aromatic group. Accordingly, the maximum content of repeating units containing aromatic group in an aliphatic polyamide herein is less than 15 mol%, based on 100 mol% of repeating units in the polymer. Preferably, the aliphatic polyamide comprises more than 85 mol%, for example 90%, etc., based on 100 mol% of monomers that make up the polyamide, of monomers comprising an aliphatic group and having no aromatic group. Although not required, such aliphatic groups can originate from a diamine monomer, and include aliphatic diamines comprising 4 to 12 carbon atoms, such as hexamethylene diamine (HMDA), nonane diamine, 2-methyl-1, 5-pentadia. ina, and 1, 4-diaminobutane, etc. A useful diacid source of aliphatic units is adipic acid. Useful examples of aliphatic polyamides L2 of the invention include aliphatic nylon (eg, PA6, PA6.6, PA4.6, PA6.12, PA4.6, PAll, and PA6.12, etc.). Of course, more than one aliphatic polyamide can be used in the polyamide L2 composition. In addition, the impact modifiers described above can be used in the polyamide composition L2, if desired. Additives The polyamide compositions Ll and L2 can each, individually, optionally, further contain one or more additives. Useful additives include, for example, an external lubricant, such as PTFE or low density polyethylene (LDPE) to facilitate extrusion. Suitable pulverized PTFE include POLYMIST® F5A available from Solvay Solexis.

Another useful additive is a thermal stabilizer. Suitable thermal stabilizers include copper-containing stabilizers comprising a copper compound soluble in the polyamide and an alkali metal halide. More particularly, in certain embodiments the stabilizer comprises a copper (I) salt, for example cuprous acetate, cuprous stearate, a cuprous organic complex compound such as copper acetylacetonate, a cuprous halide or the like, and an alkali metal halide. In certain embodiments of the present invention, the stabilizer comprises a copper halide selected from copper iodide and copper bromide and an alkali metal halide selected from the iodides and bromides of lithium, sodium, and potassium. The formulations comprising copper (I) halide, an alkali metal halide and a phosphorus compound can also be used to improve the stability of films formed from polyphthalamide compositions during prolonged exposure at temperatures up to about 140 ° C. . The amount of stabilizer used is preferably sufficient to provide a level from about 50 ppm to about 1000 ppm copper. Preferred compositions of the invention comprise an alkali metal halide and a copper (I) halide in a weight ratio in the range of from about 2.5 to about 10, more preferably from about 8 to about 10. Generally, the combined weight of compound of copper halide and alkali metal in a stabilized polyamide composition ranges from about 0.01% by weight to about 2.5% by weight. In certain different stabilized polyamide compositions used to form films according to the present invention, the stabilizer is present in the range of from about 0.1 wt% to about 1.5 wt%. A stabilizer particularly suitable for polyamide compositions according to the present invention comprises tablets of a mixture by weight of : 1 potassium iodide and cuprous iodide with a magnesium stearate binder. The potassium iodide / cuprous iodide thermal stabilizer provides protection against long-term thermal aging, such as exposure to car temperatures under the hood. Another useful additive is a filler such as reinforcing filler, or structural fibers. Structural fibers useful in the formation of filled articles and composite products include fiberglass, carbon or graphite fibers and fibers formed from silicon carbide, alumina, titania, boron and the like, as well as resin fibers designed for high temperatures such as such as, for example, poly (benzothiazole), poly (benzimidazole), polyarylates, poly (benzoxazole), aromatic polyamides, polyaryl ethers and the like, and may include mixtures comprising two or more of said fibers. Suitable fibers useful herein include glass fibers, carbon fibers and aromatic polyamide fibers such as fibers marketed by the DuPont Company under the trademark KEVLAR®. Another useful additive is an antioxidant. Useful antioxidants include Nauguard 445, phenols (eg Irganox 1010, Irganox 1098 from Ciba), phosphites, phosphonites (for example, Irgafos 168 from Ciba, P-EPQ from Clariant or Ciba), thiosynergists (for example Lowinox DSTDP from Great Lakes), interrupted amine stabilizers (eg Chimasorb 944 from Ciba), hydroxyl amines, benzofuranone derivatives, phenols modified with acryloyl, etc. Other fillers that can also be used in polyamide compositions according to the invention include antistatic additives such as carbon powders, multi-walled carbon nanotubes and single walled nanotubes as well as flakes, filler in the form of fibrous and spherical particles, agents of reinforcement and nucleation such as talcum, mica, titanium dioxide, potassium titanate, silica, kaolin, limestone, alumina, mineral fillers, and the like. Fills and structural fibers can be used alone or in any combination. Additional useful additives include, without limitation, pigments, colorants, flame retardants, and the like including those additives commonly used in the arts of resins. The additives can be used alone or in any combination, as necessary. For particular application it may also be useful to include plasticizers, lubricants, and mold releasing agents, as well as thermal, oxidizing and light stabilizers, and the like. The levels of said additives can be determined for the particular use contemplated by an expert in the art in view of this description. Methods The films of the invention can be made by any technique known in the art or further developed, including in particular, extrusion. In this regard, one skilled in the art is capable of forming the films of the invention as described herein using the polyamide compositions Ll and L2 in view of this description. The physical dimensions of the film of the invention are not limited. The preferred thicknesses of single layer films vary from 5 microns to 1000 microns (0.05 to 1 mm), more preferably 15 microns (0.15 to 0.9 mm), including all values and vary from, particularly 50, 100, 200, 400, 600 and 800 microns. Films of the invention of modified impact polyamide can be extruded in the normal manner, for example of existing film lines, and can provide very thin films (e.g., 5 to 50 microns) if desired. As discussed above, the films can be mono- or multi-layer. The properties of the fibers can be varied by varying the proportions of the materials that make up the film, and by varying the film-forming process. Films of two layers of different Lis or L1 / L2 can be produced without the need for layers. Films of three or more than three layers can also be prepared. Excellent results were obtained particularly with: films comprising, as single layers, at least one layer; films that comprise, as a single layer, a layer Ll (monolayer films); - films comprising, as single layers, at least two layers Ll; - films comprising as single layers, at least one layer Ll and at least one layer L2; films comprising, as single layers, two layers, the first being a layer Ll and the other being a layer L2 (bilayer films); In such films, Ll can be either the inner or outer layer; - films comprising, as a single layer, three layers of L1 / L2 / L1, where Ll is either an inner or outer layer and L2 is the intermediate layer. The films of the invention have high high tensile properties and high impact strength; and showed good resistance to abrasion. The mechanical strength, rigidity and resistance to rupture are improved by biaxial orientation. Accordingly, the films of the invention can be used in a variety of situations where polyamide films are usually employed but provide better results. The films of the invention capture water more slowly than and have a low transmission speed in relation to conventional polyamide films (PA 6 or PA 66). Accordingly, films of the invention, in one embodiment, can be used in hot water applications where low permeation and higher temperature is required. The films of the invention also have significantly lower permeation rates for fuel, and gases than conventional polyamide films such as polyamide films 12, 11, 6 or 66. Accordingly, in another embodiment, films of the invention may be used at higher temperatures and can be used in high temperature fuel system applications, and particularly at higher temperatures than conventional polyamide films. In another embodiment, the films of the invention can be used as insulating devices in electric motors and in other electronic devices. The use of the films of the invention in electronic applications is improved by means of superior thermal performances and stable electrical properties in conventional polyamide films of high relative humidity such as PA 12, PA 11, PA 66 or PA 6. In other In this embodiment, the films of the invention can be used as a substrate for flexible printed circuits and automated ribbon laminates. A laminate can be bonded on both sides of the film and use known acrylics and epoxies to achieve bonding. Films can also be used in industrial transformers for insulators and insulators of compressor motor windings, etc. The films of the invention have excellent chemical resistance to a wide variety of materials such as esters, ketones, weak acids, aliphatic and aromatic hydrocarbons, etc. Unlike conventional aliphatic polyamides, such as PA 6 or 66, the films of the present invention have good resistance to alcohols. Accordingly, in another embodiment, the films of the invention can be used as corrosion-resistant protectors in the manufacture or preparation of chemicals. EXAMPLES Illustrative examples of the present invention, but not limiting thereof, are provided below. Table 1 describes two compositions. In addition, a control composition of AMODEL® A-1006 PPA was prepared without modification.

Table 1 The films of Examples 1, 2 and Cl were produced by extrusion. For these examples, the films were produced by co-extrusion / encapsulation. The fit for this process is shown in Figure 1. Two 30 mm El and E2 extruders were used. Standard polyamide and polyethylene screws were used. The extruders were connected to a die-T via a feed block. The PPA tablets were fed in the El extruder and a degree of polyethylene of the grade for high viscosity tube (Eltex® B4922) was in E2. The PPA film was encapsulated between the polyethylene. There was no adhesion of the PPA film to the polyethylene film. The detachment of the central PPA layer from the HDPE layers was easy. The adjustment conditions are shown in Table 2. Table 2 Depending on the speed of the screw and the separation of the matrices, the films of Example 1 and 2 and the Cl control of 50 to 300 microns in thickness could be obtained. ISO IBA tensile specimens were drilled from the films. They were elongated at a head speed of 0.5 mm / min tested under the conditions of IS0527. As shown later in Table 3, impact modifications provided polymeric compositions having higher average tensile elongation to deformation and rupture on the unmodified Cl control. In fact, PPA compositions of the invention comprising impact modifiers had elongation to strain and rupture more than twice as high as the control. The highest tensile elongation at deformation and rupture provided greater latitude in the processing parameters for protection applications and thermoforming applications of the present invention. Table 3 Film extrusion without encapsulation Formulation Example 2 was run on a 18 mm single screw Brabender machine. The adjustment is similar to Figure 1 except that the T-die was replaced with a 100 mm wide slot die. A standard polyamide screw was used. The settings of the rear and front barrel were from 250 to 330 ° C. With a screw RPM of 25 mm and a torque of 4 kN, films of 50-150 microns thick were obtained, depending on the roll speed. Extrusion of large-scale films Formulation Example 2 was run on a commercially sized single screw equipment (76 mm in diameter). The screw was a 20: 1 / L / D with a compression ratio of 3: 1. The rollers were heated to 125 ° C. Barrel adjustments from back to front were adjusted from 310 to 325 ° C. The adapter and the die were adjusted to 330 ° C. With a screw speed of 70 rpm, the 0.4 mm thick film was produced at speeds of 2 to 7 meters / minute depending on the discharge pressure. The tensile properties of the previous film were measured by means of ASTM D638: Tensile strength to deformation = 54.6 MPa Elongation to deformation = 5.2% Tensile strength to rupture = 67.8 MPa Elongation to rupture = 110% This clearly demonstrates the commercial utility in the manufacturer of a modified impact polyphthalamide film and that the properties are acceptable for the intended end use. Protective properties The fuel permeation tests were conducted on the example compositions, control, and comparative compositions. The results of the fuel permeation tests are shown in Table 4 below. The fuel permeation tests on the films of the same specimens as those listed in Table 3. In addition to the modified impact compositions of Examples 1 and 2, permeability measurements were carried out on PA 12, PA 6, Solef® 1010 PVDF and Cl (Amodel A-1006). The fuel tested is CTF1, 45/45/10 by volume of the isooctane / toluene / ethanol mixture. See SAEJl681 standard rev. Jan. 2000. The measured fuel permeability was expressed as the number of grams of permeant that would permeate through a sheet of thickness of 1 mm and a sheet surface area of 1 2 in a period of 1 day. The permeability of the modified impact PPA, Examples 1 and 2, is far from being higher than that of the aliphatic polyamides (PA 6 and PA 12) and similar to that of PVDF. • In spite of the fact that the incorporation of elastomers in the PPA compositions of the invention is generally thought to be detrimental to the protective properties of PPA, very good protective properties were retained. Table 4 Thermoforming The films of Example 2 of 0.4 mm thickness were successfully thermoformed. A square piece of film is held in a structure, similar to the canevá of a painting. The structure It is indicated in an oven at 290 to 300 ° C for 15-45 seconds. The indicated structure of the furnace directly on the instrument. Once the instrument is started and the film is thermoformed in the desired article. Temperatures below 280 ° C cause the film to be rigid when formed. A temperature higher than 305 ° C causes the film to form blisters or sheath. Die-Cutting 0.4 mm thick Example 2 films were successfully die-cut in a variety of ways using commercial equipment. This technique is useful for the formation of flexible circuit boards for the electronics industry. Comparisons of thermal aging with PA12 Table 5 describes two thermally stabilized compositions (Example 3 and Example 4).

Table 5 A comparison of the compositions according to Examples 3 and 4 with thermally stabilized PA12 is given in Table 6.

Table 6 As can be seen, PA12 suffers a catastrophic loss in Izod impact resistance after thermal aging. Consequently, partially modified aromatic polyamides are a safer selection for retaining impact properties after long-term exposure at elevated temperatures in the presence of air. As described herein, in certain embodiments of the present invention, the film comprises a monolayer structure of composition Ll. As used herein, a "monolayer" is formed of a single layer of a polymer composition wherein the polymer composition is substantially the same throughout the entire layer. In certain embodiments of the present invention, the thickness of the monolayer may vary from about 0.05 mm to about 1.0 mm. In certain embodiments of the present invention, the thickness of the monolayer varies from about 0.15 mm to 0.9 mm. Films may have surfaces that are rough, smooth, corrugated, etc. that they are of a constant thickness throughout the film or of variable thickness, etc. In addition, the films of the invention may be used to enclose or encapsulate a content, and the content may vary widely. For example, the film of the invention is also described as actively containing or retaining its intended content. The description of the invention written above provides a way and a process of developing and using it so that any expert in the field will be facilitated to elaborate and use it, this facility being provided in particular for the subject matter of the appended claims. ', which are part of the original description and include a film comprising, as single layers, (l) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and, optionally, (2) at least one layer L2 comprising an aliphatic polyamide. Similarly preferred embodiments of the invention provided include films wherein the aromatic polyamide is a polyphthalamide; the aliphatic polyamide is an aliphatic nylon; the impact modifier is selected from the group consisting of EPDM, SEBS, and mixtures thereof; the aromatic polyamide is a polyamide having at least 50 mol% of recurring units obtained by means of a polycondensation reaction between at least one dicarboxylic acid selected from the group consisting of phthalic, terephthalic, and isophthalic acids and mixtures thereof and minus an aliphatic diamine; the polyphthalamide comprises from about 50 mol% to about 95 mol% of hexamethylene terephthalamide units, from about 25 mol% to about 0 mol% of hexamethylene isophthalamide units, and from 50 mol% to about 5 mol% of hexamethylene adipamide units; the impact modifier is an elastomer, the elastomer is an elastomer based on functionalized polyolefins; the elastomer based on functionalized polyolefins is a styrene-ethylene-butylene-styrene block copolymer functionalized with maleic anhydride; the elastomer based on functionalized polyolefins is a monomeric ethylene-propylene-diene elastomer functionalized with maleic anhydride; the layers are contiguous layers of the order of [(Ll) n / (L2) m] x where x is any integer of 1 or greater, n is any integer of 1 or greater, and m is any integer; the layer Ll additionally comprises an external lubricant; the external lubricant is selected from the group consisting of polytetrafluoroethylene, low density polyethylene, and mixtures thereof; The layer Ll further comprises a thermal stabilizer comprising at least one copper salt (I) and at least one alkali metal halide, the thermal stabilizer comprises at least one copper halide selected from the group consisting of copper iodide and bromide copper and at least one alkali metal halide selected from the group consisting of the iodides and bromides of lithium, sodium, and potassium; the film consists of, as a single layer, a monolayer comprising an aromatic polyamide and an impact modifier; and a method for making a film comprising as single layers, (1) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and, optionally, (2) at least one layer L2 comprising an aliphatic polyamide, which comprises extruding an aromatic polyamide and an impact modifier, and optionally extruding an aliphatic polyamide. As used herein, where a certain polymer is mentioned as being "obtained from" or "comprising", etc. one or more monomers (or monomer units) this description is of the finished polymer material by itself and the repeating units therein which constitute, wholly or partially, this finished product. A person skilled in the art will understand that, specifically speaking, a polymer does not include individual, unreacted "monomers," but is preferably made up of repeat units derived from the monomers that reacted. All references, patents, applications, tests, standards, documents, publications, brochures, texts, articles, etc. which are mentioned in the present, are incorporated therein as a reference. Similarly, all brochures, technical information sheets, etc., for all commercially available materials are incorporated herein by reference. When a numerical limit or interval is declared, endpoints are included. Also, all values and subintervals in a numerical limit or range are specifically included as if they were explicitly transcribed. The above description is presented to enable an expert in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Accordingly, this invention is not intended to be limited to the modes shown, but is to be in accordance with the broadest scope consistent with the principles and aspects described herein.

Claims (27)

NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty, and therefore the content of the following is claimed as property: CLAIMS

1. A film characterized in that it comprises as a single layer, (1) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and, optionally, (2) at least one layer L2 comprising an aliphatic polyamide.

2. The film according to claim 1, characterized in that the aromatic polyamide is a polyphthalamide.

3. The film according to claim 2, characterized in that the film comprises at least one layer L2, and in that the aliphatic polyamide is an aliphatic nylon.

The film according to claim 1, characterized in that the impact modifier is selected from the group consisting of EPDM, SEBS, and mixtures thereof.

5. The film according to claim 1, characterized in that the aromatic polyamide is a polyamide having at least 50 mol% of recurring units obtained by means of a polycondensation reaction between at least one dicarboxylic acid selected from the group consisting of phthalic acids, terephthalic, and isophthalic, and at least one aliphatic diamine.

The film according to claim 2, characterized in that the polyphthalamide comprises from about 50 mol% to about 95 mol% of hexamethylene terephthalamide units, from about 25 mol% to about 0 mol% of hexamethylene isophthalamide units, and from about 50 Molar% to approximately 5 mol% of hexamethylene adipamide units.

7. The film according to claim 1, characterized in that the impact modifier is an elastomer.

8. The film in accordance with the claim 7, characterized in that the elastomer is an elastomer based on functionalized polyolefin.

9. The film in accordance with the claim 8, characterized in that the elastomer based on the functionalized polyolefin is a styrene-ethylene-butylene-styrene block copolymer functionalized with maleic anhydride.

The film according to claim 8, characterized in that the elastomer based on the functionalized polyolefin is a monomeric ethylene-propylene-diene elastomer functionalized with maleic anhydride.

The film according to claim 6, characterized in that the impact modifier is selected from the group consisting of a monomeric ethylene-propylene-diene elastomer functionalized with maleic anhydride, a styrene-ethylene-butylene-styrene block copolymer. functionalized with maleic anhydride, and mixtures thereof.

The film according to claim 1, characterized in that said layers are contiguous layers of the order of [(Ll) n / (L2) m] x where X is any integer of 1 or greater, n is any integer of 1 or greater, and m is any integer.

The film according to claim 1, characterized in that the layer Ll additionally comprises an external lubricant.

The film according to claim 13, characterized in that the external lubricant is selected from the group consisting of polytetrafluoroethylene, low density polyethylene, and mixtures thereof.

15. The film according to claim 1, characterized in that the layer Ll additionally comprises a thermal stabilizer comprising at least one copper salt (I) and at least one alkali metal halide.

The film according to claim 15, characterized in that the thermal stabilizer comprises at least one copper halide selected from the group consisting of copper iodide and copper bromide and at least one alkali metal halide selected from the group consisting of the iodides and bromides of lithium, sodium, and potassium.

17. The film according to claim 1, characterized in that it consists of, as a single layer, a monolayer comprising an aromatic polyamide and an impact modifier.

18. The film according to claim 17, characterized in that the layer Ll additionally comprises an antioxidant.

19. The film according to claim 22, characterized in that the anti-oxidant is selected from the group consisting of hindered phenols, amines, and mixtures thereof.

20. A method for making a film characterized in that it comprises, as single layers, (1) at least one layer Ll comprising an aromatic polyamide and an impact modifier, and, optionally, (2) at least one layer L2 comprising an aliphatic polyamide , which comprises extruding an aromatic polyamide and an impact modifier, and optionally extruding an aliphatic polyamide, into a film.

21. The film according to claim 1, characterized in that it comprises, as a single layer, at least one layer Ll.

22. The film according to claim 21, characterized in that it comprises, as a single layer, a layer Ll.

23. The film according to claim 21, characterized in that it comprises, as single layers, at least two layers Ll.

The film according to claim 1, characterized in that it comprises, as single layers, at least one layer Ll and at least one layer L2.

25. The film according to claim 24, characterized in that it comprises, as single layers, two layers, the first one being a layer Ll and the other being a layer L2.

26. The film according to claim 25, characterized in that Ll is the inner layer.

27. The film according to claim 25, characterized in that Ll is the outer layer. The film according to claim 24, characterized in that it comprises, three layers of L1 / L2 / L1, where Ll is both an inner layer and an outer layer and L2 is the intermediate layer.