Electrostatic dissipative polyamide compositions and articles containing same

Abstract

1. A polyamide composition comprising: (A) (A1) 60-90 weight percent (wt%) of at least one semi-aromatic polyamide polymer; (A2) 10-40 wt% of at least one aliphatic polyamide polymer; (A3) 20-69 wt% of a polyamide blend comprising 0-30 wt% of at least one aliphatic polyamide polymer different from the aliphatic polyamide polymer (A2), wherein the wt% of each of (A1), (A2) and (A3) is based on the total weight of (A1), (A2) and (A3); (B) 1-20 wt% of a conductive material; (C) 30-55 wt% of glass flakes; and (D) 0-10 wt% of an additive, wherein the wt% of each of (A), (B), (C) and (D) is based on the total weight of the polyamide composition. Articles comprising such polyamide compositions have particularly excellent mechanical and surface properties and are suitable for applications requiring tight dimensional tolerances and ESD properties for optimum functionality.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS Not applicable

[0002] Electrostatic dissipative polyamide compositions The present invention relates to electrostatic dissipative polyamide compositions and also to articles, such as molded articles, especially electronic equipment components, comprising such polymer compositions. [Background technology]

[0003] Attempts have been made to use liquid crystal polymers (LCPs) with high heat resistance in electronics applications that require molded parts with tight dimensional tolerances. To improve the mechanical properties of LCPs, fillers such as talc and milled glass can be added to improve tensile strength and modulus. However, problems still arise when attempting to use such materials in molded parts with tight dimensional tolerances. For example, mechanical properties are often insufficient or inconsistent, leading to poor filing and lack of dimensional stability in molded parts. Furthermore, increasing the amount of filler to improve mechanical properties can result in a surface that is too rough, which can lead to errors in the performance of the molded part in its intended application.

[0004] Therefore, there is a need for LCP-free polymer compositions that can be easily used to mold parts with tight dimensional tolerances, and yet achieve better mechanical and surface properties.

[0005] Semicrystalline polyamides have good mechanical properties and processability, making them suitable for various applications requiring good mechanical performance.Polyamide molded articles are widely used in the engineering field, especially for electronic components, and in automotive components.Due to the demand for molded articles with reduced weight but high mechanical strength, these articles are generally reinforced with fillers, especially fibrous fillers.In particular, polyphthalamides are valued for their high temperature performance due to their high glass transition temperature Tg and high melting temperature Tm.

[0006] However, semi-crystalline polyamides exhibit anisotropic mold shrinkage as a result of crystallization, and fibrous reinforcing fillers such as glass fibers exacerbate this effect. Additionally, dimensional stability, such as the coefficient of linear thermal expansion (CLTE), or moisture expansion, is also anisotropic, resulting from the semi-crystalline polymer morphology and the high aspect ratio of the reinforcing fillers.

[0007] Polyamides, like most plastic resins, are insulating materials. Indeed, plastic resins are often considered for use as electrical insulating materials because they typically do not readily conduct electrical current and are generally fairly inexpensive compared to other known insulating materials. While many known plastics are sufficiently durable and heat resistant to provide at least some degree of electrical insulating effectiveness, many such plastics are problematic due to the buildup of static charge on the surface of the material.

[0008] Such surface charge buildup can be undesirable for a variety of reasons. Such materials can discharge very quickly, which can damage electronic components or cause fires or explosions, depending on the environment. Sudden static discharges can also be a nuisance to people using the materials.

[0009] Even if sudden static discharge is not an issue, dust particles are typically attracted to and will accumulate on materials that have a static charge. Additionally, static charges can interfere with sensitive electronic components or devices, etc.

[0010] Resistivity can be defined to include surface resistivity and volume resistivity. When volume resistivity is within the appropriate range, an alternative path is provided through which charge can dissipate (generally along the surface). In fact, surface resistivity is typically the primary focus for electrostatic dissipative ("ESD") polymeric materials.

[0011] Surface resistivity is a measurement of the electrical resistance (typically measured in ohms per square, or "Ω / sq") measured at the surface of a material at room temperature. 5 If the dielectric constant is less than Ω / sq, the surface of the composition has very little insulating ability and is generally considered to be conductive. Such compositions are generally poor static dissipative polymeric materials because the bleed-off rate is too high.

[0012] Surface resistivity is 10 12 If the surface resistivity is greater than Ω / sq, the surface of the composition is generally considered to be an insulator. In certain applications, such compositions are also poor static dissipative materials, as the surface does not have the necessary amount of conductivity required to dissipate static charges. Typically, a surface resistivity of about 10 5 ~10 12 Ω / sq, any charge that comes into contact with the surface will be easily dissipated or "dead." Further information on evaluating surface and volume resistivity can be found in American Standard Test Method D257. Summary of the Invention

[0013] It is therefore an object of the present invention to provide a polyamide composition for use in producing polyamide-based articles, preferably molded articles, having electrostatic dissipation (ESD) properties, suitable dimensional stability, and improved mechanical properties. Particular embodiments further provide polyamide-based molded articles with improved surface properties, such as high gloss.

[0014] This combination of properties makes such articles suitable for electronic applications, particularly as electronic components requiring tight dimensional tolerances, smooth surfaces, and ESD properties for optimum functionality.

[0015] The present invention solves various problems associated with anisotropic mold shrinkage and dimensional change (low warpage) in polyamide-based molded articles (such as components for electronic devices) that have very tight dimensional tolerances. "Warpage" refers to the deformation of a molded part in one or more directions that can be caused by anisotropic shrinkage of the resin during molding.

[0016] The present invention also solves the problem of insufficient static dissipation in polyamide-based articles or devices that accumulate static charges generated during their operation by facilitating the slow dissipation of these charges. Without conductive material, the polyamide-based article or device would be insulating and charge dissipation would not occur. On the other hand, with too much conductive material, the polyamide-based article or device would have too low a resistivity (too high a conductivity), thereby resulting in the article or device being grounded, which can hinder its performance.

[0017] In some embodiments, the present invention also solves problems associated with surface roughness, such as low gloss, in molded articles made from polymer compositions having high filler content.

[0018] A first aspect of the present invention is directed to a polyamide composition comprising a polyamide blend, a conductive material, and glass flakes. The polyamide composition may further comprise one or more optional additives, such as a reinforcement agent different from the glass flakes, a heat stabilizer, a lubricant, an impact modifier, a UV stabilizer, a dye, a pigment, a colorant, etc.

[0019] In some particular embodiments, the polyamide composition comprises: A) A1) 60 to 90% by weight of at least one semi-aromatic polyamide polymer; A2) 10 to 40 wt. % of at least one aliphatic polyamide polymer; A3) 0 to 30% by weight of at least one aliphatic polyamide polymer different from the aliphatic polyamide polymer (A2). 35 to 50 weight percent (wt%) polyamide blend comprising: the respective weight percents of each of the polyamides (A1), (A2) and (A3) being based on the total weight of the combination of polyamides (A1), (A2) and (A3), and the polyamide blend; B) 1 to 20 wt. % of a conductive material; C) 30-55 wt. % glass flakes; D) 0 to 10% by weight of additives Including, Here, the weight percentages of A, B, C and D are based on the total weight of the polyamide composition.

[0020] A second aspect of the present invention relates to a process for producing a polyamide composition according to the present invention, said process comprising melt blending a polyamide mixture (A), a conductive material (B), glass flakes (C) and any optional additives (D).

[0021] A third aspect of the present invention relates to a molded article comprising a polyamide composition according to the present invention.

[0022] A fourth aspect of the present invention relates to an electronic device component comprising the polyamide composition according to the present invention.

[0023] Another aspect of the present invention relates to a method for reducing the volume resistivity of a polyamide-based molded article, comprising melt-blending a polyamide mixture (A), glass flakes (C), and optional additives (D) with an electrically conductive material (B) to form a molding composition, and then subjecting the molding composition to molding, preferably injection molding, to form the molded article.

[0024] The various aspects, advantages, and features of the present invention will be more readily understood and appreciated with reference to the detailed description and examples.

[0025] definition In this descriptive specification, several terms are intended to have the following meanings.

[0026] As used herein, polyamides are generally obtained by polycondensation between at least one aromatic or aliphatic saturated diacid and at least one aliphatic saturated or aromatic primary diamine, lactam, amino acid or a mixture of these different monomers.

[0027] As used herein, an aliphatic polyamide polymer contains at least 50 mole percent repeat units having an amide bond (—NH—CO—) and does not contain any aromatic groups. In other words, both the diacid moiety and the diamine, lactam, or amino acid moiety that form the repeat units of the polyamide by polycondensation do not contain any aromatic groups.

[0028] As used herein, a "semicrystalline" polyamide has a heat of fusion ("ΔH") of at least 5 joules per gram (J / g) as measured using differential scanning calorimetry at a heating rate of 20°C / min. f Similarly, as used herein, an amorphous polyamide has a ΔH of less than 5 J / g as measured using a differential scanning calorimeter at a heating rate of 20° C. / min. f ΔH f can be measured according to ASTM D3418. In some embodiments, ΔH f is at least 20 J / g, or at least 30 J / g, or at least 40 J / g.

[0029] As used herein, polyphthalamide (PPA) is generally obtained by polycondensation between at least one diacid and at least one diamine, in which at least 55 mole % of the diacid moieties of the repeating units in the polymer chain are terephthalic acid and / or isophthalic acid, and the diamine is aliphatic.

[0030] The term "nano" as used herein with reference to a three-dimensional structure, e.g., a tube, sheet, flake, disk, sphere, or any other 3-D structure, refers to a structure having at least one dimension smaller than about 0.1 micrometer (less than 100 nanometers) and an aspect ratio from the largest dimension to the smallest dimension of about 50:1 to about 5000:1. The dimensions of nano 3-D structures can be measured by dynamic light scattering (DSL) and / or direct measurement on micrographs obtained by scanning electron microscopy (SEM).

[0031] As used herein, the selection of one element from a group of elements also refers to - the selection of two elements or the selection of several elements from the group, - Selection of an element from a subgroup of elements consisting of a group of elements from which one or more elements have been removed Explicitly state:

[0032] In the following sections of the specification, any description made in connection with a particular embodiment may be applicable to and interchangeable with other embodiments of the present disclosure. Each embodiment defined in this manner may be combined with other embodiments unless otherwise indicated or clearly incompatible. In addition, it should be understood that elements and / or features of compositions, parts or articles, processes, methods, or uses described herein may be combined, explicitly or implicitly, with other elements and / or features of compositions, parts or articles, processes, methods, or uses in any possible manner, without departing from the scope of the specification.

[0033] The recitation herein of a range of values ​​for a variable defined by a lower limit or an upper limit, or by a lower limit and an upper limit, also includes embodiments in which the variable is selected within that range of values, excluding the lower limit, or excluding the upper limit, or excluding the lower and upper limits, respectively. Any recitation herein of numerical ranges by endpoints includes all numbers subsumed within the recited range, as well as the endpoints of the range, and equivalents thereof.

[0034] The term "comprising" (or "comprises") encompasses "consisting essentially of" (or "consisting essentially of") and also "consisting of" (or "consisting of").

[0035] As used herein, "consisting essentially of" with respect to a polyamide composition or components thereof means that the content of any component not expressly listed is less than 1 wt.%, or less than 0.5 wt.%, or less than 0.1 wt.%, or less than 0.05 wt.%, or less than 0.01 wt.%.

[0036] Use of the singular form "a" or "one" herein includes the plural unless specifically stated otherwise. DETAILED DESCRIPTION OF THE INVENTION

[0037] It has surprisingly been found that when the polyamide composition according to the present invention comprises a polyamide mixture (A), an electrically conductive material (B), glass flakes (C), and optionally an additive (D), the resulting polyamide composition leads to polyamide-based molded articles having static dissipation properties, improved shrinkage and / or warpage properties and / or good dimensional stability (CLTE), while exhibiting excellent mechanical performance.

[0038] The volume resistivity of polyamide-based molded articles is such that molded articles containing such polyamide compositions according to the invention are electrostatic dissipative (ESD) materials. This combination of components (A), (B), and (C) and, optionally, (D), makes the polyamide compositions according to the invention suitable for electronic applications where dimensional tolerances are tight and ESD properties are required for optimal function. Preferably, molded articles containing such polyamide compositions according to the invention are electronic equipment components, particularly portable electronic equipment components.

[0039] In some embodiments, the polyamide-based molded articles or electronic components, particularly portable electronic components, further exhibit good surface properties, such as smooth surfaces as characterized by high gloss.

[0040] In some particular embodiments, the polyamide composition comprises: A) A1) 60 to 90% by weight of at least one semi-aromatic polyamide polymer; A2) 10 to 40 wt. % of at least one aliphatic polyamide polymer; A3) 0 to 30% by weight of at least one aliphatic polyamide polymer different from the aliphatic polyamide polymer (A2). A polyamide mixture comprising 20 to 69% by weight of the respective weight percents of each of the polyamides (A1), (A2) and (A3) being based on the total weight of the combination of polyamides (A1), (A2) and (A3), and the polyamide blend; B) 1 to 20 wt. % of a conductive material; C) 30-55 wt. % glass flakes; D) 0 to 10% by weight of additives Including, Here, the weight percentages of each of components (A), (B), (C) and (D) are based on the total weight of the polyamide composition.

[0041] In some embodiments, the polyamide composition according to the present invention contains no more than 5 wt. %, preferably no more than 2 wt. %, and more preferably no more than 1 wt. % of polymers other than polyamide polymers (A1), (A2) and (A3).

[0042] In some embodiments, the polyamide composition according to the present invention consists essentially of a polyamide blend (A), a conductive material (B), glass flakes (C), and optionally one or more additives (D).

[0043] In some embodiments, the polyamide composition comprises: A) 25-55% by weight of a polyamide mixture; B) 5 to 15 wt. % of a conductive material; C) 40-55 wt. % glass flakes; D) 0 to 10% by weight of additives Including, Here, the weight percentages of each of components (A), (B), (C) and (D) are based on the total weight of the polyamide composition.

[0044] In a more particular embodiment, the polyamide composition comprises: A) 30-50% by weight of a polyamide mixture; B) 5 to 15 wt. % of a conductive material; C) with 45-50 wt.% glass flakes; D) 0 to 10% by weight of additives Including, Here, the weight percentages of each of components (A), (B), (C) and (D) are based on the total weight of the polyamide composition.

[0045] In some embodiments, the polyamide composition has a melting temperature, Tm, of at least 300° C., at least 305° C., or at least 310° C. Additionally or alternatively, in some embodiments, the polyamide composition has a Tm of 360° C. or less, 350° C. or less, or 345° C. or less. In some embodiments, the polyamide polymer has a Tm of 300° C. to 360° C., 305° C. to 350° C., or 310° C. to 345° C. Tm can be measured according to ASTM D3418.

[0046] Polyamide mixture (A) The polyamide composition according to the present invention comprises 20 to 69 wt %, or 25 to 55 wt %, or 30 to 50 wt % of the polyamide mixture (A) based on the total weight of the polyamide composition.

[0047] The polyamide mixture (A) comprises at least two polyamide polymers: at least one is a semi-aromatic polyamide polymer and at least another is an aliphatic polyamide polymer.

[0048] In some embodiments, at least a portion of the polyamide blend (A) in the polyamide composition is bio-based.

[0049] The polyamide mixture (A) is preferably A1) 60 to 90% by weight of at least one semi-aromatic polyamide polymer; A2) 10 to 40 wt. % of at least one aliphatic polyamide polymer; A3) 0 to 30% by weight of at least one aliphatic polyamide polymer different from the aliphatic polyamide polymer (A2). Including, Here, the weight percentage of each of the polyamides (A1), (A2) and (A3) is based on the total weight of the combination of the polyamides (A1), (A2) and (A3).

[0050] In some embodiments, the polyamide mixture (A) is A1) 85 to 90% by weight of at least one semi-aromatic polyamide polymer; A2) 10 to 15% by weight of at least one aliphatic polyamide polymer Including, Here, the weight percentages of each of the polyamides (A1) and (A2) are based on the total weight of the combination of the polyamides (A1) and (A2).

[0051] In some embodiments, the polyamide mixture (A) is A1) 85 to 90% by weight of PA6T / 66; A2) 10 to 15% by weight of PA12 Including, Here, the weight percentages of each of the polyamides (A1) and (A2) are based on the total weight of the combination of the polyamides (A1) and (A2).

[0052] In some embodiments, the polyamide mixture (A) is A1) 60 to 65% by weight of at least one semi-aromatic polyamide polymer; A2) 10 to 15 wt. % of at least one aliphatic polyamide polymer; A3) 20 to 30% by weight of at least one aliphatic polyamide polymer different from the aliphatic polyamide polymer (A2). Including, Here, the weight percentage of each of the polyamides (A1), (A2) and (A3) is based on the total weight of the combination of the polyamides (A1), (A2) and (A3).

[0053] In some embodiments, the polyamide mixture (A) is A1) 60 to 65% by weight of PA6T / 66; A2) 10 to 15 wt% PA12, A3) 20 to 30% by weight of PA610 Including, Here, the weight percentage of each of the polyamides (A1), (A2) and (A3) is based on the total weight of the combination of the polyamides (A1), (A2) and (A3).

[0054] In some embodiments of polyamide blend (A), when an aliphatic polyamide polymer (A3) is present, the weight percent of polyamide (A3) based on the combined weight of the different polyamides (A1), (A2), and (A3) is higher than the weight percent of aliphatic polyamide polymer (A2) based on the combined weight of the different polyamides (A1), (A2), and (A3).

[0055] In some embodiments of the polyamide mixture (A) that does not contain an aliphatic polyamide polymer (A3), the weight ratio of (A1) / (A2) may be 5.66-9.0, preferably 6.5-9.

[0056] In some embodiments of the polyamide mixture (A) containing an aliphatic polyamide polymer (A3), the weight ratio of polyamide (A1) to polyamide (A2)+(A3) may be 1.33 to 2.15, preferably 1.5 to 2, more preferably 1.6 to 1.8.

[0057] Semi-aromatic polyamide (A1) In some embodiments, the polyamide mixture (A) comprises 60 to 90 wt. %, preferably 60 to 65 wt. % or 85 to 90 wt. % of the semi-aromatic polyamide polymer (A1), where the wt. % of polyamide (A1) is based on the total weight of the combination of polyamides (A1), (A2) and (A3).

[0058] In some embodiments, the polyamide blend (A) comprises 60-65 wt. % of the semi-aromatic polyamide polymer (A1), where the wt. % of polyamide (A1) is based on the total weight of the combination of polyamides (A1), (A2), and (A3). Such embodiments are preferred when the polyamide blend comprises an aliphatic polyamide (A3) that is different from the aliphatic polyamide (A2).

[0059] In some embodiments, the polyamide blend (A) comprises 85% to 90% by weight of semi-aromatic polyamide polymer (A1), where the weight % of polyamide (A1) is based on the total weight of the combination of polyamides (A1), (A2) and (A3). Such embodiments are preferred when the polyamide blend does not comprise an aliphatic polyamide (A3).

[0060] In some embodiments, the semi-aromatic polyamide (A1) comprises or consists essentially of a polyamide selected from the group consisting of PA10T / 10I, PA6T / 66, PA6T / 6I, PA6I / 66, PA6T / 6, PA6I / 6, PA6I / 66, PA6T / 6I / 66, PA6T / 6I / 6, PA10T / 66, PA6T, PA6I, PA9T, PA10T, PA12T, PA12I, PAMXD6, PAPXD10, and any combination thereof.

[0061] In a preferred embodiment, the semi-aromatic polyamide (A1) comprises or consists essentially of polyphthalamide.

[0062] In some embodiments, the semi-aromatic polyamide (A1) is a polymer obtained by polycondensation of isophthalic acid and / or terephthalic acid with an aliphatic diamine having 6 to 12 carbon atoms. In standard nomenclature, "T" and "I" are combined with a number indicating the length of the aliphatic monomer. For example, PA6T is derived from hexamethylenediamine and terephthalic acid. Suitable polyphthalamides for the semi-aromatic polyamide (A1) include copolymers selected from PA6T / 66, PA6T / 6I, PA6I / 66, PA6T / 6, PA6I / 6, PA6T / 6I / 66, PA6T / 6I / 6, or any combination thereof. Other suitable polyphthalamides for the semi-aromatic polyamide (A1) include homopolymers selected from PA6T, PA6I, PA9T, PA10T, PA12T, PA12I, or any combination thereof.

[0063] In a more preferred embodiment, the semi-aromatic polyamide (A1) comprises or consists essentially of a polyphthalamide selected from the group consisting of PA6T / 66, PA6T / 6I, PA10T / 66, PA6T, PA9T, PA12T, PA6I, and any combination thereof.

[0064] In an even more preferred embodiment, the semi-aromatic polyamide (A1) comprises or consists essentially of PA6T / 66 and optionally a polyamide selected from the group consisting of PA10T / 10I, PA6T / 6I, PA6I / 66, PA6T / 6, PA6I / 6, PA6I / 66, PA6T / 6I / 66, PA6T / 6I / 6, PA10T / 66, PA6T, PA6I, PA9T, PA10T, PA12T, PA12I, PAMXD6, PAPXD10, and any combination thereof. In such an embodiment, more than half (by weight) of the semi-aromatic polyamide (A1) is PA6T / 66.

[0065] In a most preferred embodiment, the semi-aromatic polyamide (A1) consists essentially of PA6T / 66.

[0066] Aliphatic polyamide (A2) In some embodiments, the polyamide mixture (A) comprises 10 to 40 wt. %, preferably 10 to 15 wt. %, of at least one aliphatic polyamide polymer (A2), where the wt. % of polyamide (A2) is based on the total weight of the combination of polyamides (A1), (A2) and (A3).

[0067] In a preferred embodiment, the aliphatic polyamide polymer (A2) comprises or consists essentially of PA12.

[0068] Aliphatic polyamide (A3) In some embodiments, the polyamide mixture (A) comprises 0 to 30 wt. % of at least one aliphatic polyamide polymer (A3) different from the aliphatic polyamide polymer (A2), where the wt. % of polyamide (A3) is based on the total weight of the combination of polyamides (A1), (A2) and (A3).

[0069] In some embodiments, the aliphatic polyamide polymer (A3), which is different from the aliphatic polyamide (A2), is selected from the group consisting of PA610, PA612, PA1010, PA510, PA6, PA66, PA1012, and any combination thereof.

[0070] In some embodiments, the aliphatic polyamide polymer (A3) excludes PA12.

[0071] In a preferred embodiment, the aliphatic polyamide polymer (A3) different from the aliphatic polyamide polymer (A2) is selected from the group consisting of PA610, PA612, PA510, PA6, PA66, and any combination thereof.

[0072] In a more preferred embodiment, the aliphatic polyamide polymer (A3) different from the aliphatic polyamide polymer (A2) is selected from the group consisting of PA610, PA510, PA6, PA66, and any combination thereof.

[0073] In a most preferred embodiment, the aliphatic polyamide polymer (A3), which is different from the aliphatic polyamide polymer (A2), comprises or consists essentially of PA610.

[0074] Optional Polymer In some embodiments, the polyamide composition may include a polymer carrier used to form a masterbatch into which the additives and / or conductive materials are mixed prior to producing the polyamide composition. In such cases, the weight content (wt%) of such a polymer carrier used as a masterbatch carrier should be less than the weight content (wt%) of polyamide mixture (A), and their respective wt% are based on the total weight of the polyamide composition.

[0075] The polymeric carrier may comprise or consist of any of the polyamides (A1), (A2), and (A3) used in the polyamide composition (A), and / or may comprise or consist of a polyamide different from the polyamides (A1), (A2), and (A3) used in the polyolefin or polyamide blend (A), such as PAMXD6. PAMXD6 polymer is a polymer made from adipic acid and meta-xylylenediamine (commercially available, inter alia, as IXEF® polyarylamide from Solvay Specialty Polymers USA, LLC).

[0076] Conductive material (B) The polyamide composition also comprises 1 to 20 wt %, or 5 to 15 wt %, based on the total weight of the polyamide composition, of at least one conductive material (B), which provides improved ESD properties to an article or device or part thereof in which it is incorporated.

[0077] The conductive materials, alone or in combination, can be of any suitable shape and morphology such as continuous fibers, milled or chopped fibers either in granular form or not, flakes, powders, microspheres, nanotubes, nanoparticles, nanofibers, nanoflakes, nanoropes, nanoribbons, nanofibrils, nanoneedles, nanosheets, nanorods, carbon nanocones, carbon nanoscrolls, nanoplatelets, nanodots, dendrites, discs or any other three-dimensional body selected from the group consisting of:

[0078] In some embodiments, the conductive material (B) is 2·10 -2 Less than Ω.cm or at most 1·10 -2 Ω.cm, or at most 5·10 -3 Ω.cm, or at most 3·10 -3 Ω.cm, or at most 2·10 -3 In some embodiments, the conductive material (B) has a volume resistivity of at least 1·10 Ω·cm. -4 In some embodiments, the conductive material (B) has a volume resistivity of 1·10 Ω·cm. -4 Ω.cm~20·10 -4 It has a volume resistivity of Ω.cm or less.

[0079] In some embodiments, the conductive material (B) comprises an inorganic conductive material.

[0080] In some embodiments, the conductive material (B) comprises at least one material selected from conductive carbon black, metal flakes, metal powder, metallized glass spheres, metallized glass fibers, metal fibers, metallized whiskers, optionally metallized carbon fibers (e.g., continuous carbon fibers, chopped carbon fibers, milled carbon fibers, and / or milled / chopped carbon fibers in or without granular form), carbon nanotubes, intrinsically conductive polymers, or graphite fibrils.

[0081] In some embodiments, the conductive material (B) consists essentially of a carbon-based material.

[0082] In some embodiments, the conductive material (B) may comprise or consist of a carbon-based structure selected from the group consisting of carbon-based fibers (e.g., continuous carbon fibers, chopped carbon fibers, milled carbon fibers, and / or milled / chopped carbon fibers with or without granular form), carbon nanotubes (CNTs), carbon nanofibers, carbon nanoflakes, carbon nanoropes, carbon nanoribbons, carbon nanofibrils, carbon nanoneedles, carbon nanosheets, carbon nanorods, carbon nanocones, carbon nanoscrolls, carbon nanoohms, conductive carbon black powder, graphite fibrils, graphite nanoplatelets, nanodots, graphene, and any combination of two or more thereof.

[0083] In some embodiments, the carbon-based structure used for the conductive material (B) generally comprises at least 90% by weight carbon.

[0084] In some embodiments, the carbon-based structures used for the conductive material (B) may be metallized.

[0085] In a preferred embodiment, the carbon-based structure used for the conductive material (B) is not metallized.

[0086] Suitable carbon-based fibers, which may optionally be metallized, include, but are not limited to, continuous carbon fiber, chopped carbon fiber, milled carbon fiber, and / or milled / chopped carbon fiber, with or without granular form.

[0087] In a preferred embodiment, the conductive material (B) may comprise or consist of carbon nanotubes, continuous carbon fibers, chopped carbon fibers, milled carbon fibers, milled / chopped carbon fibers in or without granular form, conductive carbon black powder, or any combination thereof.

[0088] Carbon fibers can be continuous filaments that can be thousands of micrometers (μm) or millimeters (mm) in length, and are referred to herein as "continuous carbon fibers." Groups of continuous carbon fibers are often categorized as bundles of continuous carbon fiber filaments. Carbon fiber "tows" are typically represented as a multiplicity of thousands of filaments (represented by a K after each tow number). Carbon fiber bundles can be chopped or milled to form short segments of carbon fiber (filaments or bundles).

[0089] In various embodiments, the continuous carbon fibers have a length of about 50 mm or greater, compared to chopped or milled carbon fibers. In certain embodiments, the continuous carbon fibers have a length of about 50 mm or greater, optionally about 75 mm or greater, optionally about 100 mm or greater, optionally about 125 mm or greater, optionally about 150 mm or greater, optionally about 175 mm or greater, optionally about 200 mm or greater, optionally about 225 mm or greater, optionally about 250 mm or greater, and in certain variations, optionally about 300 mm or greater.

[0090] Chopped or milled carbon fibers typically have an average fiber length of 50 μm to 50 mm.

[0091] Suitable chopped carbon fibers compatible with polyamide are commercially available from Procotex as CF.OS.U1-6mm, CF.OS.U2-6mm, CF.OS.A-6mm, and CF.OS.I-6mm, with an average monofilament diameter of 7 microns, an average length of 6 mm, and a 15-10 -4 Ω.cm~20·10 -4 It has a volume resistivity of Ω.cm or less.

[0092] Suitable milled carbon fibers are commercially available from Procotex as CF.LS-MLD80 to CF.LS-MLD250 and have an average monofilament diameter of 7 microns, a mean length of 80 to 250 microns, and a tensile strength of 15-10 microns. -4 Ω.cm~20·10-4 It has a volume resistivity of Ω.cm or less.

[0093] Carbon nanotubes are an example of nanometer- or molecular-sized conductive materials. Carbon nanotubes can be single-walled carbon nanotubes ("SWCNTs"), double-walled carbon nanotubes ("DWCNTs"), multi-walled carbon nanotubes ("MWCNTs") (which consist of nested SWCNTs), or mixtures thereof. Preferably, the carbon nanotubes are MWCNTs. Carbon nanotubes and carbon nanoropes, such as ropes of carbon nanotubes (e.g., SWNTs or MWNTs, and ropes of SWNTs or MWNTs), exhibit high mechanical strength, electrical conductivity, and high thermal conductivity. In some embodiments, carbon nanotubes have an average aspect ratio, defined as length divided by diameter, of 100 or greater. In some embodiments, carbon nanotubes can have an average aspect ratio of 1000 or greater. In some embodiments, carbon nanotubes have an average diameter of 1 nanometer (nm) to 3.5 nm or 4 nm (roping). In some embodiments, carbon nanotubes have an average length of at least 1 μm.

[0094] Commercially available, industrial-grade carbon-based nanostructures with 90-95% C purity can be directly dispersed in polyamide polymers without pretreatment. Suitable multi-walled CNTs (MWCNTs) include the Nanocyl® NC7000 MWCNT brand, with a purity as low as 90% C, or the Nanocyl® NC3100 MWCNT brand, with a C purity greater than 95%, both manufactured by Nanocyl (Belgium). Nanocyl® NC7000 MWCNTs have an average diameter of 9.5 nanometers, an average length of 1.5 microns, and a length of 250-300 m. 2 / g BET surface area and 1·10 -4They have a volume resistivity of Ω·cm. Another suitable source of carbon-based nanostructures is FRIBIL® multi-walled carbon nanotubes manufactured by Hyperion Catalysis International. These MWCNTs can have an outer diameter of about 10 nanometers and lengths of greater than 10 microns.

[0095] In some embodiments, the conductive material (B) has a thickness of at least 0.1 m as measured by standard Brunauer-Emmett-Teller (BET) measurement. 2 / g, preferably 10m 2 / g or more, for example, about 10m 2 / g~about 500m 2 For example, a BET measurement method using a Micro-metrics TriStar II equipped with a standard nitrogen system can be used.

[0096] In some embodiments, the content of the conductive material (B) in the polyamide composition is at least 1 wt %, or at least 1.5 wt %, and / or at most 30 wt %, or at most 25 wt %, or at most 20 wt %, where wt % is based on the total weight of the polyamide composition.

[0097] When the conductive material (B) comprises carbon fiber (which includes continuous carbon fiber, chopped carbon fiber, milled carbon fiber, and / or milled / chopped carbon fiber with or without granular form), the carbon fiber content in the polyamide composition is at least 6 wt%, or at least 7 wt%, or at least 8 wt%, based on the total weight of the polyamide composition. In some of such embodiments, the carbon fiber content is at most 20 wt%, or at most 17 wt%, or at most 15 wt%, or at most 13 wt%, or at most 11 wt%, based on the total weight of the polyamide composition. In some embodiments, the carbon fiber content is from 6% to 30% by weight, or from 8% to 30% by weight, or from 6% to 25% by weight, or from 8% to 25% by weight, or from 6% to 20% by weight, or from 8% to 20% by weight, or from 6% to 15% by weight, or from 7% to 15% by weight, or from 7% to 13% by weight, or from 7% to 11% by weight, or from 8% to 15% by weight, or from 8% to 13% by weight, or from 8% to 10% by weight, based on the total weight of the polyamide composition.

[0098] When the conductive material (B) comprises carbon-based nanostructures such as carbon nanotubes (CNTs), the content of the carbon-based nanostructures in the polyamide composition is at least 1 wt%, or at least 1.5 wt%, based on the total weight of the polyamide composition. In some such embodiments, the content of the carbon-based nanostructures (e.g., CNTs) is at most 10 wt%, or at most 8 wt%, or at most 7 wt%, or at most 6 wt%, or at most 5 wt%, or at most 4 wt%, or at most 3 wt%, based on the total weight of the polyamide composition. In some embodiments, the content of the carbon-based nanostructures is 1 wt% to 5 wt%, or 1 wt% to 4 wt%, or 1 wt% to 3 wt%, or 1.5 wt% to 5 wt%, or 1.5 wt% to 4 wt%, or 1.5 wt% to 3 wt%, or 1 wt% to 8 wt%, or 1.5 wt% to 8 wt%, based on the total weight of the polyamide composition.

[0099] Glass flakes (C) The polyamide composition also contains glass flakes (C).

[0100] In some embodiments, the content of glass flakes (C) is at least 30 wt%, or at least 35 wt%, or at least 40 wt%, or at least 45 wt%, based on the total weight of the polyamide composition.

[0101] In additional or alternative embodiments, the content of glass flakes (C) is at most 55 wt. %, or at most 50 wt. %, based on the total weight of the polyamide composition.

[0102] In some embodiments, the content of the glass flakes (C) is 30% to 55% by weight, or 30% to 50% by weight, or 35% to 55% by weight, or 35% to 50% by weight, or 40% to 55% by weight, or 40% to 50% by weight, or 45% to 55% by weight, or 45% to 50% by weight, based on the total weight of the polyamide composition.

[0103] The glass flakes (C) preferably have a three-dimensional structure characterized by an average length of at most 500 microns, or at most 450 microns, or at most 400 microns, or at most 350 microns, or at most 200 microns, or at most 250 microns. For glass flakes (C) having a three-dimensional structure, their "length" is considered to be their largest dimension.

[0104] The glass flakes (C) are preferably generally 10 +12 Over Ω.cm or 5·10 +12 It is an electrically insulating filler with a volume resistivity of greater than Ω.cm.

[0105] The glass flakes (C) are preferably non-fibrous. A "non-fibrous" filler is herein considered to have a three-dimensional structure with a length, width, and thickness, both of which are significantly greater than the thickness. Generally, such glass flakes (C) with a three-dimensional structure have an aspect ratio, defined as the maximum of the average length divided by the average width and average thickness, of at most 3, or at most 2.5, or at most 2, or at most 1.5.

[0106] In some embodiments, the glass flakes (C) may have an average thickness of 0.4 microns to 10 microns, hi some embodiments, the glass flakes (C) have an average thickness of 0.4 microns to 2 microns or less, or 1 micron or less.

[0107] The dimensions (length, width, thickness) of the three-dimensional structures can be determined by direct measurements on micrographs obtained by scanning electron microscopy (SEM).

[0108] The average dimensions (i.e., length, width and thickness) of the three-dimensional structure of the glass flakes can be considered as the average length of the glass flakes (C) before incorporation into the polyamide composition or as the average dimensions of the glass flakes (C) in the polyamide composition.

[0109] Glass flake (C) is a silica-based glass compound containing several metal oxides that can be tailored to produce different types of glass. The primary oxide is silica in the form of silica sand; other oxides, such as calcium, sodium, and aluminum, are incorporated to lower the melting temperature and prevent crystallization. Any glass type, such as A, C, D, E, M, S, R, or T glass, or a mixture thereof, preferably C or E glass, can be used as the glass filler. C glass contains alkali components and has high acid resistance. E glass contains almost no alkali, so it has high stability in resins and is not electrically conductive.

[0110] In some embodiments, the glass flake (C) preferably comprises or consists of glass flakes using C-glass or E-glass. Suitable glass flakes (C) using E-glass or C-glass are commercially available from NSG as GLASFLAKE®. E-glass flakes are particularly effective in preventing warpage and improving dimensional accuracy in precision parts made from thermoplastic polymers. FINEFLAKE® glass flakes, also available from NSG, with an average thickness of 0.4 to 1 micron are suitable for fine, thin molded parts. In some embodiments, the glass flakes may be granulated. For example, FLEKA® granulated glass flakes using E-glass are commercially available from NSG.

[0111] In some embodiments, at least a portion of the glass flakes (C) may be replaced in the polyamide composition by chopped glass fibers, so long as their average length is at most 500 microns, or at most 450 microns, or at most 400 microns, or at most 350 microns, or at most 200 microns, or at most 250 microns.

[0112] In some embodiments, when glass flakes (C) comprise both glass flakes and chopped glass fibers having an average length of at most 500 microns, the glass flakes represent more than 50% by weight, or more than 60% by weight, or more than 70% by weight, or more than 80% by weight, the weight percentages being based on the combined weight of glass flakes and chopped glass fibers in (C).

[0113] In some embodiments, when the glass flakes (C) further comprise chopped glass fibers, these chopped glass fibers generally comprise: a thickness of 5 to 20 μm, preferably 5 to 15 μm, more preferably 5 to 10 μm; and / or - an average length of 100 to 500 microns, or 150 to 450 microns; and / or - aspect ratio, defined as the maximum of their average length divided by their average width and average thickness, of at most 5, or at most 3, or at most 2.5, or at most 2, or at most 1.5 It has.

[0114] The morphology of chopped glass fiber is not particularly limited. Chopped glass fiber can have a circular cross section ("round glass fiber") or a non-circular cross section ("flat glass fiber"). Examples of suitable chopped flat glass fiber include, but are not limited to, glass fibers with oval, elliptical and rectangular cross sections.

[0115] Optional Additives (D) The polyamide composition may further comprise from 0% to 20% by weight or less (based on the total weight of the polyamide composition) of one or more optional additives (D), such as reinforcing agents other than glass flakes, tougheners, plasticizers, light stabilizers, UV stabilizers, heat stabilizers, pigments, dyes / colorants, flame retardants, impact modifiers, lubricants, nucleating agents, antioxidants, processing aids, or any combination of two or more thereof, as described above.

[0116] In some embodiments, the polyamide composition may further comprise from 1 wt % to 20 wt % or less (based on the total weight of the polyamide composition) of at least one reinforcing agent different from glass flakes (C), as described above.

[0117] A wide selection of reinforcing agents, also called reinforcing fillers, may optionally be added to the polyamide composition according to the invention. They may be chosen from fibrous and particulate reinforcing agents.

[0118] The optional reinforcing agent may be selected from inorganic fillers (e.g., talc, mica, kaolin, calcium carbonate, calcium silicate, magnesium carbonate, etc.), carbon fibers, synthetic polymer fibers, aramid fibers, aluminum fibers, titanium fibers, magnesium fibers, boron carbide fibers, rock wool fibers, steel fibers, wollastonite, glass beads (e.g., hollow glass microspheres), and glass fibers different from the glass flakes (C) used in the polyamide composition according to the invention.

[0119] The particulate reinforcing agent may be selected from inorganic fillers (eg, talc, mica, kaolin, calcium carbonate, calcium silicate, magnesium carbonate, etc.) or glass beads (eg, hollow glass microspheres).

[0120] Fibrous reinforcing fillers are considered herein to be three-dimensional materials having a length, width, and thickness, with the average length being significantly greater than both the width and thickness. Generally, such materials have an aspect ratio, defined as the ratio between the average length and the maximum of the average width and thickness, of at least 5, at least 10, at least 20, or at least 50.

[0121] In some embodiments, the optional reinforcing fibers (e.g., glass fibers) may be chopped glass fibers (as opposed to glass flakes) or continuous glass fibers having an average length of greater than 0.5 mm, preferably at least 1 mm, and no greater than 50 mm. The average length of the optional reinforcing glass fibers can be considered to be the average length of the reinforcing glass fibers prior to incorporation into the polyamide composition, or can be considered to be the average length of the reinforcing fibers in the polyamide composition.

[0122] In some embodiments, the optional glass fibers have an average length of 3 mm to 50 mm. In some such embodiments, the optional glass fibers have an average length of 3 mm to 10 mm, 3 mm to 8 mm, 3 mm to 6 mm, or 3 mm to 5 mm. In alternative embodiments, the optional glass fibers have an average length of 10 mm to 50 mm, 10 mm to 45 mm, 10 mm to 35 mm, 10 mm to 30 mm, 10 mm to 25 mm, or 15 mm to 25 mm. In some embodiments, the optional glass fibers generally have an equivalent diameter of 5 to 20 μm, preferably 5 to 15 μm, and more preferably 5 to 10 μm.

[0123] All glass types, such as A, C, D, E, M, S, R, and T glass, or any mixture thereof, or mixtures thereof, may be used. E, R, S, and T glass fibers are well known in the art. They are described, inter alia, in Fiberglass and Glass Technology, Wallenberger, Frederick T.; Bingham, Paul A. (Eds.), 2010, XIV, chapter 5, pages 197-225. R, S, and T glass fibers are essentially composed of oxides of silicon, aluminum, and magnesium. In particular, they typically contain 62-75 wt. % SiO2, 16-28 wt. % Al2O3, and 5-14 wt. % MgO. On the other hand, R, S, and T glass fibers contain less than 10 wt. % CaO.

[0124] In some embodiments, the optional glass fiber is a high modulus glass fiber. The high modulus glass fiber has a modulus of elasticity of at least 76 GPa, preferably at least 78 GPa, more preferably at least 80 GPa, and most preferably at least 82 GPa, as measured according to ASTM D2343. Examples of high modulus glass fibers include, but are not limited to, S-, R-, and T-glass fibers. Commercially available sources of high modulus glass fibers are S-1 and S-2 glass fibers from Taishan and AGY, respectively.

[0125] The optional glass fibers can be round glass fibers or flat glass fibers. Examples of suitable flat glass fibers include, but are not limited to, glass fibers having oval, elliptical, and rectangular cross sections.

[0126] In some embodiments, where the polyamide composition further comprises flat glass fibers, the flat glass fibers have a cross-sectional maximum diameter of at least 15 μm, preferably at least 20 μm, more preferably at least 22 μm, and even more preferably at least 25 μm. Additionally or alternatively, in some embodiments, the flat glass fibers have a cross-sectional maximum diameter of at most 40 μm, preferably at most 35 μm, more preferably at most 32 μm, and even more preferably at most 30 μm. In some embodiments, the flat glass fibers have a cross-sectional minimum diameter of at least 4 μm, preferably at least 5 μm, more preferably at least 6 μm, and even more preferably at least 7 μm. Additionally or alternatively, in some embodiments, the flat glass fibers have a cross-sectional minimum diameter of at most 25 μm, preferably at most 20 μm, more preferably at most 17 μm, and even more preferably at most 15 μm.

[0127] In some embodiments, the optional flat glass fibers have a ratio of the maximum diameter in a cross section of the glass fiber to the minimum diameter in the same cross section of at least 2, preferably at least 2.2, more preferably at least 2.4, and even more preferably at least 3. Additionally or alternatively, in some embodiments, this ratio for the flat glass fibers is at most 8, preferably at most 6, and more preferably at most 4.

[0128] In some embodiments where the optional fibers are round glass fibers, the glass fibers have a ratio of the largest diameter in a cross section of the glass fiber to the smallest diameter in the same cross section of less than 2, preferably less than 1.5, more preferably less than 1.2, even more preferably less than 1.1, and most preferably less than 1.05. Of course, those skilled in the art will understand that regardless of the morphology of the glass fiber (e.g., round or flat), by definition, the aspect ratio cannot be less than 1.

[0129] In some embodiments, the optional glass fibers are round or flat glass fibers selected from the group consisting of E-glass fibers; high modulus glass fibers having a tensile modulus of at least 76 GPa as measured according to ASTM D2343; and combinations thereof.

[0130] In some embodiments, when the polyamide composition comprises glass flake (C) according to the above description and at least one optional reinforcing agent, the total content of glass flake (C) plus optional reinforcing agent is at least 31 wt%, or at least 32 wt%, or at least 35 wt%, or at least 40 wt%, based on the total weight of the polyamide composition. In additional or alternative embodiments, the total content of glass flake (C) plus optional reinforcing agent is at most 60 wt%, or at most 55 wt%, or at most 50 wt%, based on the total weight of the polyamide composition. In some embodiments, the total content of glass flake (C) plus optional reinforcing agent is 31 wt% to 60 wt%, or 32 wt% to 55 wt%, or 35 wt% to 55 wt%, or 35 wt% to 50 wt%, or 40 wt% to 55 wt%, based on the total weight of the polyamide composition.

[0131] In some embodiments, when the polyamide polymer comprises glass flakes (C) plus an optional reinforcing agent, the weight of the optional reinforcing agent in the polyamide composition is preferably 10 wt. % or less, based on the total weight of the polyamide composition.

[0132] In some embodiments, the polyamide composition excludes reinforcing agents other than glass flakes (C), as described above.

[0133] In some embodiments, the polyamide composition excludes fibrous reinforcing agents having an average length greater than 0.5 mm, or greater than 1 mm.

[0134] In some embodiments, the polyamide composition excludes glass fibers having an average length greater than 0.5 mm, or greater than 1 mm.

[0135] In some embodiments, the polyamide composition excludes glass spheres or beads, and in particular hollow glass beads.

[0136] In some embodiments, the polyamide composition optionally comprises from 0.1 wt % to no more than 10 wt %, or from 0.5 to 5 wt %, of an additive selected from the group consisting of tougheners, plasticizers, light stabilizers, ultraviolet (“UV”) stabilizers, heat stabilizers, dyes, pigments, colorants, flame retardants, impact modifiers, lubricants, nucleating agents, antioxidants, processing aids, and any combination of two or more thereof.

[0137] In some embodiments where the polyamide composition comprises one or more optional additives selected from the group consisting of tougheners, plasticizers, light stabilizers, ultraviolet (“UV”) stabilizers, heat stabilizers, pigments, dyes, pigments, colorants, flame retardants, impact modifiers, lubricants, nucleating agents, antioxidants, processing aids, and any combination of two or more thereof, the total concentration of these additives is 10 wt.% or less, 5 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1 wt.% or less, and / or at least 0.1 wt.%, or at least 0.2 wt.%, or at least 0.3 wt.%, or at least 0.5 wt.%.

[0138] In some preferred embodiments, the polyamide composition comprises at least one impact modifier, heat stabilizer, dye, pigment, colorant, and / or lubricant.

[0139] In a preferred embodiment, an additive including carbon black powder may be included in the polyamide composition, e.g., as a colorant. Such carbon black powder may be added in the form of a masterbatch containing a polymer carrier. Such a masterbatch may be referred to as a "carbon black concentrate." The carbon black concentrate may be added at 1 to 10 pph, where "pph" means parts per hundred by total weight of the polyamide composition (A+B+C+D). Such carbon black powder may be conductive. However, the sole presence of such carbon black powder in a polyamide composition according to the present invention, when used alone—i.e., in the absence of conductive material (B)—will not result in a sufficient reduction in the volume resistivity of such a polyamide composition (or a molded article containing it) to produce ESD materials. However, it should be noted that this additional conductive carbon black powder as an additive (e.g., a colorant) can further reduce the volume resistivity already observed in the presence of conductive material (B).

[0140] In some embodiments, the polyamide composition does not include an antistatic additive.

[0141] In some embodiments, the polyamide composition does not include an impact modifier.

[0142] In some embodiments, the polyamide composition does not include a flame retardant.

[0143] Preparation of polyamide compositions The present invention relates to a process for producing a polyamide composition as detailed above, said process comprising melt-blending polyamide polymer (A1), polyamide polymer (A2), polyamide polymer (A3), if present, conductive material (B), glass flakes (C), one or more optional additives such as a reinforcing agent different from the glass flakes, a lubricant, a UV stabilizer, a heat stabilizer, an impact modifier, a dye, a pigment, a colorant, etc.

[0144] Any melt blending method may be used to combine polymeric and non-polymeric ingredients in connection with the present invention.

[0145] For example, the polymeric and non-polymeric ingredients can be fed into a melt mixer, such as a single-screw or twin-screw extruder, a stirrer, a single-screw or twin-screw kneader, or a Banbury mixer, and the addition step can be simultaneous addition of all ingredients or gradual batch-wise addition. When the polymeric and non-polymeric ingredients are added gradually batch-wise, a portion of the polymeric and / or non-polymeric ingredients is added first and then melt-mixed with the remaining subsequently added polymeric and non-polymeric ingredients until a well-mixed composition is obtained.

[0146] If the optional reinforcing agent exhibits a long physical form (e.g., long or "endless" fibers), stretch extrusion, pultrusion to form long fiber pellets, or pultrusion to form unidirectional composite tapes may be used to prepare the reinforced composition.

[0147] Articles and uses Another aspect of the present invention provides the use of a polyamide composition in an article.

[0148] The polyamide composition may desirably be incorporated into an article, preferably a molded article.

[0149] The articles can be used in, among other things, electrical and electronic equipment, LED packaging, electrical and electronic components (including, but not limited to, power supply unit components for computing, data systems and office equipment, and surface mount technology compatible connectors and contacts), medical device components; and electrical protection devices for mini circuit breakers, contactors, switches and sockets; automotive components, and aerospace components (including, but not limited to, interior cabin components).

[0150] The term "electronic device" is intended to mean a device that includes electronic components. Some electronic devices are not intended to be portable and to be used in various locations, while some are intended to be portable ("mobile"), such as to be easily carried by a person.

[0151] The term "portable electronic device" is intended to mean an electronic device that is designed to be conveniently carried by a person and used in a variety of settings, such as handheld, worn on the wrist or bridge of the nose, carried in a carrier such as a case, briefcase, purse, handbag, or worn or attached in and / or on a piece of clothing, etc. Representative examples of portable electronic devices may be selected from the group consisting of portable electronic phones, personal digital assistants, laptop computers, tablet computers, radios, cameras and camera accessories, wearable computing devices (e.g., smart watches, smart glasses, etc.), calculators, music players, global positioning system receivers, portable game consoles and console accessories, hard drives and other electronic storage devices.

[0152] Preferred portable electronic devices include laptop computers, tablet computers, mobile electronic phones and wearable computing devices such as watches and glasses.

[0153] Components of portable electronic devices of interest herein include, but are not limited to, antenna windows, mounting parts, snap-fit ​​parts, inter-movable parts, functional elements, actuating elements, tracking elements, adjustment elements, carrier elements, frame elements, switches, connectors, cables, housings, and any other structural parts other than housings that may be used in portable electronic devices, such as speaker parts, for example. In some embodiments, a device component can consist of a mounting component with mounting holes or other fastening devices (including, but not limited to, a snap-fit ​​connector between itself and another component of the portable electronic device, including, but not limited to, a circuit board, a microphone, a speaker, a display, a battery, a cover, a housing, an electrical or electronic connector, a hinge, a wireless antenna, a camera module, a switch, or a switch pad).

[0154] In some embodiments, the electronic device can be at least a portion of an input device.

[0155] Certain embodiments of the present invention relate to static dissipative components for electronic devices, particularly portable electronic devices. Such static dissipative components for electronic devices may be molded articles comprising the polyamide composition as described herein.

[0156] In some embodiments, a portable electronic device component may also be a portable electronic device housing. A "portable electronic device housing" refers to one or more of a back cover, a front cover, an antenna housing, a frame, and / or a skeleton of a portable electronic device. The housing may be a single item or may include two or more components. A "skeleton" refers to a structural part onto which other components of a device, such as electronics, a microprocessor, a screen, a keyboard and keypad, an antenna, a battery socket, etc., are mounted. The skeleton may be an internal component that is not visible or only partially visible from the exterior of the portable electronic device. A housing may provide protection for the internal components of the device from impact and contamination and / or damage by environmental agents (e.g., liquids, dust, etc.). A housing component, such as a cover, may also provide substantial or primary structural support for and impact protection for certain components exposed to the exterior of the device, such as a screen and / or antenna.

[0157] In some embodiments, the housing of the portable electronic device is selected from the group consisting of a mobile phone housing, an antenna housing, an antenna window, a tablet housing, a laptop computer housing, a tablet computer housing, or a watch housing.

[0158] In some embodiments, the portable electronic device component may include, for example, a wireless antenna or a camera module. In this case, the wireless antenna may be a WiFi antenna or an RFID antenna. In some such embodiments, at least a portion of the wireless antenna or camera module is disposed on the polyamide composition. Additionally or alternatively, at least a portion of the wireless antenna or camera module may be replaced by the polyamide composition.

[0159] Examples of automotive parts include, but are not limited to, automotive electronics parts, automotive lighting parts (including, but not limited to, motor end caps, sensors, ECU housings, bobbins and solenoids, connectors, circuit protection / relays, actuator housings, Li-ion battery systems, and fuse boxes), traction motors and power electronic parts (including, but not limited to, battery packs), battery housings.

[0160] Articles can be molded from the polyamide compositions by any process suitable for thermoplastics, such as extrusion, injection molding, blow molding, rotational molding, overmolding, or compression molding.

[0161] Preferred formation of molded articles or electronic components involves suitable melt processing methods such as injection molding or extrusion of the polyamide composition, with injection molding being the preferred molding method.

[0162] In some embodiments, a molded article or electronic component according to the present invention has at least one of the following properties:

[0163] In some embodiments, the polyamide-based molded article or electronic component has a viscosity of at least 1·10 +5 Ω.cm, or at least 1.5·10 +5 Ω.cm, and / or at most 5·10 +12 Ω.cm, or at most 3·10 +12 Ω.cm, or at most 1·10 +12 In some embodiments, the polyamide-based molded article or electronic component has a volume resistivity of 1·10 Ω·cm (measured according to ASTM D257). +5 Ω.cm~5·10 +12 They have a volume resistivity of Ω.cm or less, which can therefore be adjusted over at least about seven orders of magnitude by selecting a conductive material with a specific volume resistivity and by varying the conductive material content in the polyamide composition used to produce the molded article.

[0164] In some embodiments, a molded article or electronic component according to the present invention has a transverse mold shrinkage (in %), measured according to ISO 294 (ASTM D955), of at most 0.35%, or at most 0.33%, or at most 0.32%, or at most 0.31%.

[0165] In some embodiments, a molded article or electronic component according to the present invention has a ratio of machine direction mold shrinkage to cross direction mold shrinkage of greater than 55%, or greater than 60%, or greater than 65%, where the machine direction and cross direction mold shrinkage (in %) are measured according to ISO 294 (ASTM D955).

[0166] In some embodiments, a polyamide-based molded article or electronic component according to the present invention resulting from molding of a polyamide composition comprising at least one polyamide blend (A), a conductive material (B), glass flakes (C), and optionally additives (D) (such as heat stabilizers, lubricants, impact modifiers, UV stabilizers, dyes, pigments, colorants, etc.) has a lower ratio of mold shrinkage in the machine direction to the mold shrinkage in the cross direction (in %) compared to a similar composition but without the conductive material (B).

[0167] In some embodiments, a molded article or electronic component according to the present invention has a warpage of at most 0.1, or at most 0.09, where warpage is the absolute percent shrinkage in the cross direction minus the percent shrinkage in the machine direction of a molded article or electronic component comprising the polyamide composition, both % shrinkages preferably measured according to ASTM D955.

[0168] In some embodiments, a polyamide-based molded article or electronic component according to the present invention resulting from molding of a polyamide composition comprising at least one polyamide blend (A), a conductive material (B), glass flakes (C), and optionally additives (D) (such as heat stabilizers, lubricants, impact modifiers, UV stabilizers, dyes, pigments, colorants, etc.) has a lower warpage (in %) compared to a similar composition but without the conductive material (B).

[0169] In some embodiments, a polyamide-based molded article or electronic component according to the present invention resulting from molding of a polyamide composition comprising a polyamide blend (A), a conductive material (B), glass flakes (C), and optionally additives (D) (such as heat stabilizers, lubricants, impact modifiers, UV stabilizers, dyes, pigments, colorants, etc.) has improved tensile modulus, tensile strength, flexural modulus, flexural strength, and / or impact properties (notched and unnotched values) compared to a similar composition but without the conductive material (B).

[0170] In some embodiments, the polyamide-based molded article or electronic component according to the present invention resulting from molding of the polyamide composition has the following properties: - a tensile modulus (measured according to ISO 527) of at least 15 GPa or at least 16 GPa and / or at most 30 GPa, or at most 26 GPa; - a tensile strength (measured according to ISO 527) of at least 150 MPa, or at least 156 MPa and / or at most 210 MPa, or at most 200 MPa, or at most 190 MPa; - a flexural modulus (measured according to ISO 178) of at least 14 GPa and / or at most 30 GPa, or at most 25 GPa; - a flexural strength (measured according to ISO 178) of at least 200 MPa, or at least 225 MPa and / or at most 350 MPa or at most 330 MPa; - At least 3kJ / m2 or at least 3.2 kJ / m 2 and / or at most 6 kJ / m 2 notched impact (measured according to ISO 180); - At least 21.5kJ / m 2 or at least 27 kJ / m 2 and / or at most 40 kJ / m 2 Unnotched impact (measured according to ISO 180) It has one or more of the following.

[0171] Regardless of the molding technique used to produce the article, in some embodiments, a molded article or electronic component according to the present invention can have a relatively smooth surface, which can be expressed by its surface gloss. For example, the surface gloss, as measured using a glossmeter at an angle of about 80° to about 85°, can be at least 35%, or at least about 38%, or at least 40%. The surface gloss measured at an angle of about 80° to about 85° can be at most 99%, or at most 98%, or at most 97%, or at most 96%, or at most 95%, or at most 94%, or at most 93%, or at most 92%, or at most 91%, or at most 90%. A preferred range for gloss measured at an angle of about 80° to about 85° can be about 40% to 95%.

[0172] In some embodiments, when the polyamide composition omits polyamide (A3), the surface gloss measured at an angle of about 85° may range from about 40% to 60%. In other embodiments, when the polyamide composition contains polyamide (A3), the surface gloss measured at an angle of about 85° may range from about 60% to 95%, preferably from about 65% to 90%.

[0173] It is conventionally thought that parts with smooth surfaces would not have sufficiently good mechanical properties; however, to the contrary, the polyamide-based molded articles of the present invention have been found to have excellent mechanical properties, as described above and illustrated in the examples.

[0174] Use of polyamide compositions In some embodiments, the polyamide compositions or articles can be used to manufacture electronic components, preferably portable electronic components, as described above.

[0175] Method for reducing warpage and / or mold shrinkage in polyamide compositions Another aspect of the present invention relates to a method for reducing warpage and / or mold shrinkage in a molded article made from a polyamide composition, comprising blending a polyamide mixture (A), glass flakes (C), and optionally additives (D) with a conductive material (B), which preferably comprises milled carbon fiber, to form a molding composition, and then subjecting the molding composition to molding, preferably injection molding, to form a molded article. The blending is preferably carried out by melt blending as described above.

[0176] Method for reducing the volume resistivity of polyamide compositions Another aspect of the present invention relates to a method for reducing the volume resistivity of a molded article made from a polyamide composition, comprising blending a polyamide mixture (A), glass flakes (C) and optionally at least one additive (D) with an electrically conductive material (B), which preferably comprises carbon fiber or milled carbon fiber, to form a molding composition, and then subjecting the molding composition to molding, preferably injection molding, to form a molded article. The blending is preferably carried out by melt blending as described above. [Example]

[0177] The present invention will now be described with reference to the following examples, the purposes of which are merely illustrative and are not intended to limit the scope of the invention.

[0178] The following examples are Reduced volume resistivity to provide ESD materials, ○ Improved mechanical properties including: - improved impact properties, - improved tensile properties (tensile modulus, tensile strength), - Improved flexural properties (flexural modulus, flexural strength) ○ Improved mold shrinkage properties - Improved shrinkage (in / in% shrinkage in machine direction and cross direction) - Improved shrinkage ratio (% shrinkage in machine direction / % shrinkage in cross direction) - Reduced warpage (absolute value of difference between transverse shrinkage and machine shrinkage) Demonstrate the following.

[0179] Some embodiments further include: Excellent surface properties - High gloss ○ Good CLTE (dimensional stability) Demonstrate the following.

[0180] As used in the examples, "E" refers to an example embodiment of the present invention, and "CE" refers to a comparative example.

[0181] raw materials The raw materials used to form the samples are as follows: polyamide: Polyamide (A1): PA6T / 66 (Tg=100°C, Tm=311°C), such as Amodel® 4002 from Solvay Specialty Polymers (produced from the polycondensation of 65% by mole of terephthalic acid and 35% by mole of adipic acid with hexamethylenediamine). - Polyamide (A2): PA12 (Tg=40-50℃, Tm=178-180℃) such as Vestamid L-1700 manufactured by Evonik - Polyamide (A3): PA610 (Tg=50-60℃, Tm=220℃) such as Radipol DC 40 manufactured by Radici Conductive material (B): Conductive material ("B1"): granular 300 micron milled carbon fiber, commercially available from Procotex as APPLY CARBON CF MLD 300 G U1 recycled carbon fiber granules; average size of about 300±40 microns, carbon content of about 94% by weight, monofilament fiber diameter of about 7±2 microns, and 15-10 -3 It is characterized by its average volume resistivity in ohm.m. - Conductive material ("B2"): APPLY CARBON chopped carbon fiber CF.OS.U1-6MM, manufactured by Procotex Glass flakes (C): MEG160FY-M03 160 micron average length (flat) and 0.7 micron thickness, manufactured by NSG Additive (D) - Additive 1 ("D1"): Lubricant (LLDPE GRSN-9820 manufactured by Dow) Additive 2 ("D2"): heat stabilizer (Irganox® 1010 manufactured by BASF) - Additive 3 ("D3"): Carbon Black Concentrate Plasblak UN2014 manufactured by Cabot (carbon black in a polyolefin carrier) Additive 4 ("D4"): Carbon Black Concentrate CPTA-25759-CA1000 containing 80% by weight of Amodel® 1006 and 20% by weight of carbon black, manufactured by Clariant - Optional additives: pigments / dyes may be added to the polyamide composition.

[0182] Test Method ● Tensile properties - ISO 527 Tensile modulus, tensile strength, and elongation at break were measured on five injection-molded ISO Type 1a tensile specimens (total length = 170 mm, gauge length = 50 mm, test section width = 10 mm, and thickness = 4 mm). ● Flexural properties - ISO 178 Flexural modulus, flexural strength, and flexural elongation at break were measured on five injection-molded ISO Type 1A specimens (80±2 mm length, 10±0.2 mm width, 4±0.2 mm thickness). ● Impact strength - ISO 180 Notched and unnotched Izod impact strength properties were measured using 10 injection-molded ISO Type 1A specimens (80 ± 2 mm length, 10 ± 0.2 mm width, 4 ± 0.2 mm thickness) in kJ / m². 2 Measured in units. ● CLTE-ASTM E831 Dimensional change was measured on injection-molded specimens with dimensions of 3.2 mm thick x 12.7 mm wide x 12.0-13.0 mm long. CLTE was measured from 0 to 50 °C at a heating rate of 5 °C / min in the flow and transverse directions using a TMA. ● Mold shrinkage - ISO 294 (ASTM D955) ○ Mold shrinkage (machine direction mold shrinkage (%) and transverse direction mold shrinkage (%)) was measured on five injection molded plaques measuring 60 mm width x 60 mm length x 2 mm thickness. Warpage is measured as follows: Polyamide compositions were injection molded into plaques having dimensions of 60 mm x 60 mm x 2 mm according to ASTM D955, as detailed above. Warpage was calculated as the absolute value of the percent shrinkage in the transverse direction minus the percent shrinkage in the machine direction. ● Gloss Test Method - ASTM D523 Gloss was measured using shrink plaques (60 mm x 60 mm x 2 mm). Any gloss meter can be used to measure the gloss of the surface of these plaques. Gloss measurements were taken at two different locations on the surface with two repeat measurements at each location and with the light angle of incidence at 20°, 60°, or 85° relative to the surface of the plaque. The measurements were averaged to calculate the gloss. ● Volume resistivity - ASTM D257 Volume resistivity was measured on five injection molded plaques with dimensions 4 inches x 4 inches x 1 / 8 inch (length x width x thickness) or 60 mm x 60 mm x 2 mm (length x width x thickness).

[0183] Example 1 - Polyamide Blend: Polyamide composition using PA6T / 66 (as A1) and PA12 (as A2) In this example, several samples of polyamide compositions were prepared in which polyamide A1 (PA6T / 66) was compounded (melt-blended) with polyamide A2 (PA12), glass flake (C), milled carbon fiber (B1), a lubricant as additive (D1), and a heat stabilizer as additive (D2). Samples E1 and E2 further contained 1 pph of carbon black concentrate (D3). The weight ratios of semi-aromatic polyamide (A1) to aliphatic polyamide (A2) were 7.2 and 6.8 in samples E1 and E2, respectively.

[0184] For comparison, sample CE0 was prepared without milled carbon fiber. The weight ratio of semi-aromatic polyamide (A1) to aliphatic polyamide (A2) was 8.8 in sample CE0.

[0185] Melt blending was carried out using a Coperion® ZSK-26 co-rotating twin screw extruder, and the compounded samples were then molded according to ASTM D3641.

[0186] Table 1 shows the polyamide compositions and also the following properties: mechanical properties including volume resistivity, impact properties, tensile modulus, tensile strength, tensile elongation at break, mold shrinkage properties (in / in %) in machine direction and transverse direction, warpage and shrinkage ratio (% shrinkage in machine direction / % shrinkage in transverse direction) of composition samples CE0 and E1-E2.

[0187] As shown in Table 1, the addition of 8 wt. % and 10 wt. % milled carbon fiber to the polyamide composition in samples E1 and E2 reduced the volume resistivity compared to sample CE0 without milled carbon fiber. Samples E1 and E2 had volume resistivities of 10 +5 ~5·10 +12 The ohm cm range indicates static dissipation. Sample CE0 is not an ESD material.

[0188] Furthermore, the impact properties (notched Izod and unnotched Izod), tensile modulus and tensile strength of samples E1 and E2 with 8 wt% and 10 wt% milled carbon fiber (B1) were improved compared to sample CE0 without milled carbon fiber.

[0189] [Table 1]

[0190] The tensile elongation at break (%) of samples E1, E2 with 8 wt% and 10 wt% carbon fiber was slightly lower compared to sample CE0 without milled carbon fiber.

[0191] Furthermore, the mold shrinkage properties were also improved with the addition of milled carbon fiber.

[0192] With the addition of 8 and 10 wt% milled carbon fiber (B1), the transverse mold shrinkage of the polyamide compositions in Samples E1 and E2 was reduced by 36 and 39% compared to Sample CE0, indicating that the addition of 8 to 10 wt% milled carbon fiber (B1) reduces transverse mold shrinkage. Furthermore, the machine direction mold shrinkage of the polyamide compositions in Samples E1 and E2 was also reduced compared to Sample CE0 without milled carbon fiber (B1), although to a lesser extent than that observed for the transverse mold shrinkage.

[0193] The machine direction to transverse direction shrinkage ratios for samples E1, E2 were 67% and 72%, much closer to isotropic shrinkage compared to 56% for sample CE0 without milled carbon fiber.

[0194] Warpage also decreased with the addition of milled carbon fiber: Samples E1 and E2 had warpage of 0.09% and 0.07%, respectively, which was much lower than the warpage of sample CE0 without milled carbon fiber (0.19%).

[0195] The surface gloss of samples E1 and E2 with 8 and 10 wt% carbon fiber was lower compared to the value of sample CE0 without milled carbon fiber (59% at 85°). However, the gloss measured at 85° for samples E1 and E2 was still at least 40%.

[0196] The results obtained for samples E1, E2 demonstrated that the addition of 8 and 10 wt% milled carbon fiber and 50 wt% glass flake in polyamide compositions including PA6T / 66 and PA12 can result in suitable ESD materials with improved impact resistance, improved tensile modulus and strength, and also improved mold shrinkage properties (lower warpage and closer to isotropic shrinkage).

[0197] The melting temperature (Tm) was measured according to ASTM D3418 and for samples CE0, E1 and E2, with Tm values ​​ranging from 323 to 326° C. There was no adverse effect on Tm caused by the addition of milled carbon fiber in polyamide compositions including PA6T / 66 and PA12.

[0198] Example 2 - Polyamide composition using PA6T / 66 + PA12 + PA610 In this example, several polyamide compositions (Samples E4-E6) were prepared in which polyamide A1 (PA6T / 66) was melt-blended with polyamide A2 (PA12), polyamide A3 (PA610), glass flakes (C), chopped carbon fiber (B2), and a lubricant as an additive (D1). Sample E5 further contained 10 pph of carbon black concentrate (D4), while the other Samples E4 and E6 contained 1 pph of carbon black concentrate (D4). The weight ratios of semi-aromatic polyamide (A1) to aliphatic polyamide (A2) + (A3) were 1.64, 1.67, and 1.67 in Samples E4, E5, and E6, respectively.

[0199] For comparison, sample CE3 was prepared without carbon fiber (B2).

[0200] Melt blending was carried out using a Coperion® ZSK-26 co-rotating twin screw extruder, and the compounded samples were then molded according to ASTM D3641.

[0201] Table 2 shows the polyamide compositions and also the following properties: mechanical properties including volume resistivity, impact properties, tensile properties (modulus, strength, elongation at break), flexural properties (modulus, strength, elongation at break), CLTE (0-50°C) properties in the machine and transverse directions, mold shrinkage properties (in / in%) in the machine and transverse directions, warpage and shrinkage ratio (% shrinkage in machine direction / % shrinkage in transverse direction) for composition samples CE3 and E4-E6, where the sample thickness was about 2 mm.

[0202] As shown in Table 2, the addition of 8 and 10 wt. % chopped carbon fiber to the polyamide composition in samples E4 to E6 reduced the volume resistivity compared to sample CE3 without chopped carbon fiber. Samples E4 to E6 had volume resistivities of 10 +5 ~5·10 +12 The electrical resistance was in the range of ohm.cm, so it was static dissipative. Sample CE3 was not an ESD material.

[0203] The combination of 8 wt% carbon fiber and 10 pph carbon black in polyamide composition sample E5 reduced the volume resistivity by 37% compared to sample E6, which contained 8 wt% chopped carbon fiber and only 1 pph carbon black. It was therefore observed that increasing the amount of carbon black concentrate from 1 pph to 10 pph can reduce the volume resistivity.

[0204] Furthermore, the impact properties (notched Izod and unnotched Izod), tensile modulus, tensile strength, flexural modulus and flexural strength of samples E4 to E6 with 8 wt% or 10 wt% chopped carbon fiber (B2) were improved compared to sample CE3 without chopped carbon fiber.

[0205] The tensile elongation at break of samples E4-E6 with 8 wt% or 10 wt% chopped carbon fiber (B2) was slightly lower compared to sample CE3 without chopped carbon fiber. The flexural elongation at break (%) of samples E4-E6 with 8 wt% or 10 wt% carbon fiber (B2) was either the same or lower compared to sample CE3 without carbon fiber.

[0206] [Table 2]

[0207] For sample E6 (8 wt% B2, 1 pph D4), the machine direction to transverse direction shrinkage ratio was 82%, much closer to isotropic shrinkage compared to 75% for sample CE3 without milled carbon fiber. The warpage of sample E6, 0.05%, was also improved and lower than sample CE3 without chopped carbon fiber (0.08%).

[0208] On the other hand, for Sample E4 (10 wt.% B2, 1 pph D4) and Sample E5 (8 wt.% B2, 10 pph D4), the shrinkage properties were not improved. The addition of 10 wt.% chopped carbon fiber + 1 pph carbon black concentrate or 8 wt.% chopped carbon fiber + 10 pph carbon black concentrate resulted in a reduction in shrinkage in the machine direction, but did not reduce shrinkage in the transverse direction to the same extent. The higher amount of carbon fiber (in E4) and also the 10-fold higher amount of carbon black powder (in E5) likely favored fiber alignment along the machine direction. As a result, for Samples E4 and E5, the shrinkage ratios (58%, 51%) were lower than for Comparative Sample CE3, and the warpage (0.13%, 0.16%) was higher.

[0209] The surface gloss of samples E4-E6 with 8 wt% and 10 wt% carbon fiber was lower compared to the value of sample CE3 without milled carbon fiber (86.8% at 85°). However, the gloss measured at 85° for samples E4-E6 was still at least 75%, indicating retention of a smooth surface appearance.

[0210] The results obtained for samples E4 to E6 demonstrated that the addition of 8 and 10 wt. % chopped carbon fiber and 50 wt. % glass flakes in polyamide compositions including PA6T / 66, PA12 and PA610 can result in suitable ESD materials with improved impact resistance, improved tensile modulus and strength, improved flexural modulus and strength, and excellent surface properties (high gloss).

[0211] Sample E5 also showed improved mold shrinkage properties (lower warpage and closer to isotropic shrinkage).

[0212] When comparing Example 2 with Example 1, it is also observed that the addition of PA610 (as polyamide (A3)) to a mixture of PA6T / 66 and PA12 (as polyamides (A1) and (A2)) resulted in an ESD material with a smooth surface (high gloss).

[0213] Tm was measured according to ASTM D3418. For samples CE3 and E4-E6, the Tm values ​​were 336-340° C. There was no adverse effect on Tm caused by the addition of chopped carbon fiber in polyamide compositions including PA6T / 66, PA12, and PA610.

[0214] While preferred embodiments of the present invention have been shown and described, modifications thereof can be made by those skilled in the art without departing from the spirit or teachings of the present invention. The embodiments described herein are illustrative only and not limiting. Many variations and modifications of the compositions, articles, and methods are possible and within the scope of the present invention. Accordingly, the scope of protection is not limited by the description set forth above, but only by the following claims, which scope includes all equivalents of the subject matter of the claims. Each and every claim is incorporated herein as an embodiment of the present invention. Accordingly, the claims are further explanation and in addition to the preferred embodiments of the present invention. Any incorporation by reference of the above documents is limited so that no subject matter contrary to the express disclosure herein is incorporated.

[0215] The disclosures of all patent applications and publications cited herein, to the extent that they provide exemplary, procedural, or other details supplementary to those set forth herein, are hereby incorporated by reference. In the event that the disclosure of any patent, patent application, and publication incorporated herein by reference contradicts the statement of this application to the extent that it may render a term unclear, the statement shall control.

Claims

1. 1. A polyamide composition comprising: (A) A1) 85 to 90 wt.% PA6T / 66, A2) 10 to 15% by weight of PA12 (Here, the weight percentages of each of the polyamides (A1) and (A2) are based on the total weight of the combination of polyamides (A1) and (A2).) or A1) 60 to 65 wt.% PA6T / 66, A2) 10 to 15 wt.% of PA12, A3) 20 to 30% by weight of PA610 (Here, the weight percentages of each of the polyamides (A1), (A2) and (A3) are based on the total weight of the combination of the polyamides (A1), (A2) and (A3).) 20 to 69 wt. % of a polyamide blend consisting of: (B) 6 to 20 weight percent of a conductive material selected from the group consisting of continuous carbon fiber, chopped carbon fiber, milled carbon fiber, and any combination thereof; (C) 30 to 55 wt. % glass flakes; (D) 0 to 10 wt. % of an additive; Including, The weight percentages of each of A, B, C and D are based on the total weight of said polyamide composition.

2. 2. The polyamide composition of claim 1, wherein the glass flake content is from 35 to 55% by weight, or from 35 to 50% by weight, or from 40 to 50% by weight, or from 45 to 50% by weight, based on the total weight of the polyamide composition.

3. 3. The polyamide composition according to claim 1 or 2, further comprising at least one additive selected from the group consisting of reinforcing agents, toughening agents, plasticizers, light stabilizers, UV stabilizers, heat stabilizers, pigments, colorants, dyes, flame retardants, impact modifiers, lubricants, nucleating agents, antioxidants, processing aids, and any combination of two or more thereof, different from the glass flakes (C).

4. The conductive material (B) is 2.10 －２ Less than Ω.cm or at most 1.10 －２ Ω cm, or at most 5.10 －３ Ω.cm, or at most 3.10 －３ Ω cm, or at most 1.10 －３ 4. The polyamide composition according to any one of claims 1 to 3, having a volume resistivity, measured according to ASTM D257, of Ω.cm.

5. The polyamide composition according to claim 1, wherein the conductive material (B) has a volume resistivity, measured according to ASTM D257, of 1·10 −4 Ω·cm to 20·10 −4 Ω·cm.

6. 25 to 55% by weight of said polyamide mixture (A); - 5 to 15% by weight of said conductive material (B); - 40 to 55% by weight of said glass flakes (C); and - 0 to 10% by weight of one or more additives (D); or - 30 to 50% by weight of said polyamide mixture (A); - 5 to 15% by weight of said conductive material (B); - 45 to 50% by weight of said glass flakes (C); and 0 to 10% by weight of one or more additives (D) The polyamide composition according to any one of claims 1 to 5, comprising:

7. A polyamide composition according to any one of claims 1 to 6, which does not contain more than 5% by weight of polymers other than the polyamide polymers (A1), (A2) and (A3).

8. A polyamide composition according to any one of claims 1 to 7, which does not contain more than 2% by weight of polymers other than polyamide polymers (A1), (A2) and (A3).

9. A polyamide composition according to any one of claims 1 to 8, which does not contain more than 1% by weight of polymers other than the polyamide polymers (A1), (A2) and (A3).

10. The polyamide composition of claim 1, wherein the polyamide composition exhibits a melting temperature (Tm), measured according to ASTM D3418, of from 300°C to 360°C, from 305°C to 350°C, or from 310°C to 345°C.

11. 11. A method for producing the polyamide composition of any one of claims 1 to 10, comprising melt blending the polyamide mixture (A), the conductive material (B), the glass flakes (C), and any optional additives (D).

12. 1.10 ＋５ Ω.cm~5・10 ＋１２ A molded article comprising the polyamide composition of any one of claims 1 to 10, having a volume resistivity, measured according to ASTM D257, of Ω.cm.

13. 1.10 ＋５ Ω.cm~5・10 ＋１２ A portable electronic device part comprising the polyamide composition according to any one of claims 1 to 10, having a volume resistivity, measured according to ASTM D257, of Ω.cm.

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