Halogen-free, flame-retardant, compatibilized polyamide and polyphenylene ether blends

Abstract

A composition comprising a compatibilized blend of a polyamide, a polyphenylene ether, and a flame retardant, which interact synergistically such that a plaque made from the composition passes the Glow Wire Ignition Temperature Test (GWIT) without producing a flame. Advantageously, the flame retardant is non-halogenated, and the composition is also free of other halogen-containing components. Moreover, surprisingly, the composition is capable of passing the test without the inclusion of a filler.

Description

[Technical field]

[0001] The present invention relates to a composition comprising a compatibilized blend of a polyamide, a polyphenylene ether and a flame retardant, which interact synergistically such that a plaque made from the composition passes the Glow Wire Ignition Temperature Test (GWIT) without producing a flame. Advantageously, the flame retardant is non-halogenated, and the composition is also substantially free of other halogen-containing components. Moreover, in some embodiments, the composition is surprisingly capable of passing the test without the inclusion of a filler. [Background technology]

[0002] Compositions comprising a majority of polyamide and polyphenylene ether polymer content are used to produce molded parts for a wide variety of industrial end uses such as electrical components and connectors and automotive parts (e.g., exterior parts and parts close to the engine such as engine covers) because they exhibit desirable properties including one or more of processability, good flame retardant performance, good stability, and good mechanical properties.

[0003] In the prior art, various approaches have been taken to meet customer demands, such as, for example:

[0004] China Patent Publication No. 109553967 reportedly relates to a low precipitation halogen-free flame retardant polyphenylene ether-polyamide resin alloy and its preparation method, in which the raw materials include 10-50 wt% polyphenylene ether, 15-65 wt% mixed polyamide resin including polyamide MX and polyamide 66 derived from m-xylylenediamine and diacid, 5-25 wt% halogen-free flame retardant, 3-15 wt% compatibilizer which is maleic anhydride grafted polystyrene-polyethylene-polybutene-polystyrene linear triblock copolymer or maleic anhydride grafted polyphenylene ether, 3-15 wt% toughening agent of polystyrene-polyethylene-polybutene-polystyrene linear triblock copolymer, 0.1-0.5 wt% antioxidant, 0.2-0.6 wt% nucleating agent, and 0.5-1 wt% other processing aids. The prepared material is reported to be able to meet high glow-wire ignition temperatures in high temperature and humidity environments, not burn at temperatures of 800°C during the process, and exhibit low migration and precipitation of flame retardants under harsh conditions. The prepared low-precipitation halogen-free flame-retardant polyphenylene ether-polyamide resin alloy material is reported to combine good flame retardant performance, good mechanical properties, and good dimensional stability.

[0005] CN110698852 relates to a flame-retardant reinforced polyamide 6 / polyphenyl ether composition, which is prepared from the following raw materials: low viscosity polyamide 6 resin, high viscosity polyphenyl ether resin, low viscosity polyphenyl ether resin, styrene and glycidyl methacrylate copolymer, toluene diisocyanate, hydrogenated styrene-isoprene copolymer grafted maleic anhydride, N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,3-benzenedicarboxamide, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate, zinc pentaerythritol, silane coupling agent, layered silicate, alkyl phosphinate, melamine polyphosphate and alkali-free glass fiber. It is reported that the composite material prepared from the flame-retardant reinforced polyamide 6 / polyphenyl ether composition has excellent mechanical properties, processability and flame retardancy, and can be used in the manufacture of automobiles, electronic and electrical parts, etc.

[0006] US Patent Publication No. 2018 / 057685 relates to a resin composition that is reported to have excellent flame retardancy, moldability, and flame retardancy after heat aging. The composition includes (A) polyphenylene ether, (B) at least one thermoplastic resin selected from the group consisting of (B-1) polystyrene-based resin, (B-2) polyamide-based resin, (B-3) polypropylene-based resin, and (B-4) polyphenylene sulfide resin, and (C) a flame retardant. The content of component (A) is less than 50% by mass when the amount of the flame retardant resin composition minus the ash content is taken as 100% by mass. The flame retardant level of the flame retardant resin composition is V-0 grade as measured by the UL94 vertical flame test. A molded article formed from this flame-retardant resin composition exhibits a change rate of chloroform-insoluble matter of 15% by mass or less before and after aging treatment in which the molded article is left in an atmospheric environment at 150° C. for 1,000 hours.

[0007] US Patent Application Publication No. 2009 / 027582 relates to a resin composition containing (A) a polyamide having a viscosity number (measured in 96% sulfuric acid according to ISO307 (1997) standard) of 50 ml / g to 250 ml / g, (B) a polyphenylene ether, and (C) a phosphinate represented by a specific chemical formula. This resin composition is reported to have excellent flame retardancy, impact resistance, and thin-wall moldability, and is reported to be able to significantly suppress gas generation during the molding process and substantially suppress the generation of deposits on the mold during injection molding. As a result, it is reported that this resin composition can provide molded articles with excellent appearance.

[0008] Further efforts include flame retarding unfilled polyamides using the non-halogenated flame retardant melamine cyanurate. This technology meets the flame retardancy requirements of UL94 V0 rating very well. However, when subjected to glow wire testing, flames are generated. Nevertheless, molded plaques capable of passing IEC60695-2-13 testing can be produced from such formulations, because the flame is extinguished in less than 5 seconds.

[0009] Additionally, halogenated flame retardant technologies such as brominated polystyrene in combination with antimony trioxide are often flame-free when used in glass-free polyamide formulations. This technology is typically superior in the gas phase, i.e., it acts to prevent ignition of decomposition materials that enter the gas phase as a result of partial combustion, thus helping to prevent flames and pass the GWIT test. However, according to various customer and regulatory requirements, halogenated formulations should not be used.

[0010] In light of the above, the industry still needs improved unfilled compositions because many connectors include parts such as flanges or latches that require good ductility to function properly. This is generally a difficult task to achieve. For example, the addition of glass fibers to polymer-based formulations reduces flammability, but often results in more brittle parts, causing latches and flanges to break very easily. There remains a need in the art for compositions that do not produce a flame when molded into parts and / or plaques and tested according to a standardized glow wire test. Summary of the Invention

[0011] The above and other problems of the prior art are solved by the composition of the present invention, which is a blend of non-halogenated, compatibilized polyamide and polyphenylene ether, including a flame retardant, that passes the GWIT IEC 60695-2-13 plaque test at thicknesses up to and including 2.0 mm at various temperatures, such as at least 700°C, 750°C, 775°C, and 800°C, without producing a flame, the latter being a more restrictive, additional provision not required by the test specification. For clarity, terms such as "without producing a flame," "flameproof," "no flame," and the like require that the specimen tested does not ignite or produce any flame visible to the human eye when contacted with a glow wire according to a particular test method.

[0012] The compositions of various embodiments may also meet UL94 VO requirements at thicknesses between 0.4 mm and 3.0 mm, and UL 5VA requirements at thicknesses between 1.5 mm and 3.0 mm.

[0013] It is highly unexpected that the compositions of the present invention and parts made therefrom meet such stringent flame retardant requirements, considering that the compositions do not contain halogen-containing flame retardants and in some embodiments do not contain reinforcing fillers. Small parts for the applications described herein are preferably manufactured by injection molding and incorporate design features such as flanges, sockets, latches, retention mechanisms and various profiles that should be stable and long-lasting. A very specifically defined range of polyamide (co)polymers is utilized to impart mechanical strength and processability. A defined range of polyphenylene ethers does not impair the properties imparted by the polyamide (co)polymers and helps to form a char layer, essentially preventing decomposed or burned chemical moieties from contributing to the reaction that causes a flame. Furthermore, a synergistic amount of flame retardant enhances the composition to ensure that it does not emit a flame according to the modified test of the present invention.

[0014] Accordingly, in one embodiment, a halogen-free, flame resistant, compatibilized polyamide and polyphenylene ether blend composition is disclosed, the composition comprising: a polyamide (co)polymer present in an amount of about 30 to about 80 parts by weight per 100 parts by weight of the composition, the polyamide (co)polymer being present as a continuous phase in said composition; a polyphenylene ether in an amount of about 15 to about 50 parts by weight per 100 parts by weight of the total amount of said composition; and a block copolymer compatibilizer derived from i) said polyamide (co)polymer, ii) said polyphenylene ether, and iii) a compatibilizer, the block copolymer compatibilizer being derived from said polyamide (co)polymer, ii) said polyphenylene ether, and iii) a compatibilizer, the block copolymer compatibilizer being present in said polyphenylene ether. The compatibilizer has two different types of functional groups including i) a first functional group capable of reacting with a polyamide (co)polymer and ii) a second functional group capable of reacting with a polyphenylene ether, the compatibilizer comprises a block copolymer compatibilizer present in an amount of about 0.1 to about 5 parts by weight based on 100 parts by weight of the composition, and a flame retardant which is a phosphinate present in an amount of about 5 to about 35 parts by weight based on 100 parts by weight of the composition, the composition does not comprise a halogen-containing flame retardant, and a plaque or plate prepared from the composition does not emit a flame at 700°C at a thickness of 2.0 mm and passes a test conforming to the GWIT IEC 60695-2-13 standard.

[0015] In further embodiments, the polyamide (co)polymer is one or more of polyamide 6; polyamide 6,6; polyamide 4,6; polyamide 11; polyamide 12; polyamide 6,10; polyamide 6,12; polyamide 6 / 6,6; polyamide 6 / 6,12; polyamide MXD (m-xylylenediamine),6; polyamide 6,T; polyamide 9,T; polyamide 6,I; polyamide 6 / 6,T; polyamide 6 / 6,I; polyamide 6,6 / 6T; polyamide 6,6 / 6,I; polyamide 6 / 6,T / 6,I; polyamide 6,6 / 6,T / 6,I; polyamide 6 / 12 / 6,T; polyamide 6,6 / 12 / 6,T; polyamide 6 / 12 / 6,I; and polyamide 6,6 / 12 / 6,I.

[0016] In yet another embodiment, the flame retardant is one or more of aluminum diethylphosphinate, zinc diethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum dipropylphosphinate, isopropyl phosphinate, aluminum butylphosphinate, aluminum methylethylphosphinate, and aluminum phenylphosphinate.

[0017] In another embodiment, the composition does not include a filler.

[0018] In a further embodiment, a plaque or plate prepared from the composition is flame-free at 750° C. at a thickness of 2.0 mm and passes testing according to GWIT IEC 60695-2-13 standard.

[0019] In yet another embodiment, a plaque or plate prepared from the composition is flame-free at 800° C. at a thickness of 2.0 mm and passes testing according to GWIT IEC 60695-2-13 standard.

[0020] In another embodiment, the polyamide (co)polymer is present in an amount of about 30 to about 70 parts by weight per 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 15 to about 50 parts by weight per 100 parts by weight of the total composition, the compatibilizer is present in an amount of about 0.2 to about 4 parts by weight per 100 parts by weight of the composition, and the flame retardant is present in an amount of about 7.5 to about 30 parts by weight per 100 parts by weight of the composition.

[0021] In a further embodiment, the polyamide (co)polymer is present in an amount of about 32 to about 65 parts by weight per 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 20 to about 45 parts by weight per 100 parts by weight of the total composition, the compatibilizer is present in an amount of about 0.25 to about 3 parts by weight per 100 parts by weight of the composition, and the flame retardant is present in an amount of about 10 to about 25 parts by weight per 100 parts by weight of the composition.

[0022] In yet another embodiment, the composition further comprises a lubricant.

[0023] In another embodiment, the polyphenylene ether is present as a discontinuous phase in the blend.

[0024] In further embodiments, the polyphenylene ether is one or more of poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), and a copolymer of 2,6-dimethylphenol and another phenol.

[0025] In yet another embodiment, the compatibilizer is one or more of maleic acid, maleic anhydride, fumaric acid, citric acid, and citric acid anhydride.

[0026] In another embodiment, the first functional group is one or more of a carbon-carbon double bond and a carbon-carbon triple bond, and the portion of functional groups is one or more of a carboxyl group, an acid anhydride, an epoxy group, an amide group, an ester group, and an acid chloride.

[0027] In yet another embodiment, the polyamide copolymer has an amine group concentration of 50 milliequivalents / kg or greater.

[0028] In another embodiment, the polyamide copolymer has an amine group concentration of 60 meq / kg or greater.

[0029] In another aspect, a method for forming the blend composition is disclosed, the method comprising reacting the compatibilizer with a portion of the polyphenylene ether and the polyamide copolymer, thereby forming the block copolymer compatibilizer.

[0030] In a further aspect, the method includes reacting a portion of the polyphenylene ether with a compatibilizer prior to mixing with the polyamide.

[0031] In yet another embodiment, the blend is extruded, a compatibilizer and a portion of the polyphenylene ether are combined at an upstream feed location, and the polyamide is added downstream after the compatibilizer and a portion of the polyphenylene ether have reacted. [Brief description of the drawings]

[0032] The invention will be better understood, and other features and advantages will become apparent, from a reading of the detailed description of the invention in conjunction with the drawings, in which:

[0033] [Figure 1] FIG. 1 shows black and white images of several different connectors that can be produced with the composition of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] In this specification, all numbers disclosed herein individually designate set values ​​in one embodiment, regardless of whether words such as "about" or "approximate" are used in conjunction therewith. Furthermore, when terms such as "about" or "approximate" are used in conjunction with a value, the numerical range may also vary, for example, by 1%, 2%, or 5% or more in various other independent embodiments. All ranges described in this specification and claims include not only the endpoints of the range, but also all possible numbers between the endpoints of the range.

[0035] The terms "polymer" and "(co)polymer" as used herein refer to a polymeric compound prepared by polymerizing monomers, whether of the same or different types. As used herein, the terms encompass the terms "homopolymer", "copolymer", "terpolymer" and "interpolymer". The term "interpolymer" as used herein refers to a polymer prepared by polymerization of at least two different types of monomers.

[0036] Compositions and / or parts made with the compositions of the present invention (see figures for non-limiting examples) pass the GWIT IEC60695-2-13 test and the GWFI IEC60695-2-12 test without producing a flame, even though the compositions do not contain any halogen-containing flame retardants or any other halogen-containing components, and in some embodiments, do not contain any fillers.

[0037] polyamide

[0038] Polyamide (co)polymers are present in the compositions of the present invention. Polyamides typically exhibit properties such as good chemical resistance, mechanical strength and processability, and polyamides have excellent injection moldability. However, some polyamides have less than desirable heat resistance and dimensional stability.

[0039] The polyamide of the present invention is used in an amount sufficient for the polyamide to form a continuous phase of the composition. For clarity, the polyamide may be present in an amount less than 50% by weight based on the total weight of the composition, even though it forms a continuous phase. From the standpoint of microstructure, the polyamide and polyphenylene ether are believed to have an islands-in-a-sea structure, with the polyphenylene ether as discrete islands in a sea of ​​polyamide.

[0040] Polyamide (co)polymers suitable for use in the present invention are generally obtained by ring-opening polymerization of lactams, polycondensation of diamines and dicarboxylic acids, polycondensation of ω-aminocarboxylic acids, etc. However, it is not intended that the polyamides of the present invention be limited to resins obtained by these methods.

[0041] Examples of the diamines mentioned above include three major categories of diamines: aliphatic diamines, alicyclic diamines, and aromatic diamines.Specific examples of the diamines include aliphatic diamines, such as tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, tridecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,2-dimethyl-2,4-dimethylphenyldiamine, 1,3-dimethylphenyldiamine, 1,4-dimethylphenyldiamine, 1,5-dimethylphenyldiamine, 1,6-dimethylphenyldiamine, 1,7-dimethylphenyldiamine, 1,8-dimethylphenyldiamine, 1,9-dimethylphenyldiamine, 1,7-dimethylphenyldiamine, 1,8-dimethylphenyldiamine, 1,9-dimethylphenyldiamine, 1,5 ...8-dimethylphenyldiamine, 1,9-dimethylphenyldiamine, ,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, and 5-methyl-1,9-nonanediamine; 1,3-bisaminomethylcyclohexane; 1,4-bisaminomethylcyclohexane; m-phenylenediamine; p-phenylenediamine; m-xylylenediamine; and p-xylylenediamine.

[0042] Examples of the dicarboxylic acids include three major categories of dicarboxylic acids: aliphatic dicarboxylic acids, cycloaliphatic dicarboxylic acids, and aromatic dicarboxylic acids.Specific examples of the dicarboxylic acids include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, 1,1,3-dodecanedioic acid, 1,3-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, and dimer acid.

[0043] Specific examples of the lactam include ε-caprolactam, enantholactam, and ω-laurolactam.

[0044] Specific examples of the aminocarboxylic acid include ε-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 9-aminonoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and 13-aminotridecanoic acid.

[0045] According to the present invention, the lactams, diamines, dicarboxylic acids and ω-aminocarboxylic acids may be polycondensed individually or may be used in the form of a copolyamide obtained by polycondensing a mixture of two or more of them.

[0046] In addition, a product obtained by polymerizing the lactam, diamine, dicarboxylic acid or ω-aminocarboxylic acid in a polymerization reactor to the stage of a low molecular weight oligomer and then converting the oligomer into a high molecular weight polymer using an extruder or the like can also be suitably used.

[0047] Examples of polyamides particularly suitable for use in the present invention include polyamide 6; polyamide 6,6; polyamide 4,6; polyamide 11; polyamide 12; polyamide 6,10; polyamide 6,12; polyamide 6 / 6,6; polyamide 6 / 6,12; polyamide MXD (m-xylylenediamine), 6; polyamide 6,T; polyamide 9,T; polyamide 6,I; polyamide 6 / 6,T; polyamide 6 / 6,I; polyamide 6,6 / 6T; polyamide 6,6 / 6,I; polyamide 6 / 6,T / 6,I; polyamide 6,6 / 6,T / 6,I; polyamide 6 / 12 / 6,T; polyamide 6,6 / 12 / 6,T; polyamide 6 / 12 / 6,I; and polyamide 6,6 / 12 / 6,I. Various polyamides obtained by copolymerizing a plurality of the above polyamides using an extruder or the like may also be used.

[0048] Among these, preferred polyamides are aliphatic polyamides (e.g., polyamide 6; polyamide 6,6; polyamide 4,6; polyamide 11; polyamide 12), and semi-aromatic polyamides (e.g., polyamide 9,T; polyamide 6 / 6,T; polyamide 6,6 / 6,T; polyamide 6,6 / 6,I; polyamide MXD,6), as well as combinations thereof. At least one polyamide selected from the group consisting of polyamide 6,6; polyamide 6; polyamide 66 / 6; and combinations thereof is most preferred. Polyamide 6I / 6T can also be added as a second polyamide to help improve other properties, such as improved moisture resistance, improved surface aesthetics, and improved flame retardancy (FR). Copolymers such as polyamide 66 / 6T with a T ratio of 20-40% are also suitable.

[0049] The melting points of polyamides are generally in the range of about 200°C to about 280°C, but can be higher or lower depending on the customer requirements and the products made from the compositions of the present invention. The melting temperature is about 262°C for polyamide 66. The melting temperature is about 220°C for polyamide 6. The melting point of polyamide 66 is usually above 240°C, but depends on the ratio of polyamide 6 to polyamide 66. The melting temperature is generally higher than 262°C for polyamide 66 / 6T copolymers, making them useful in desired applications requiring higher temperatures.

[0050] In a preferred embodiment, the polyamide has available amine groups (-NH2) at the ends of the polymer chains. The amine groups react with the functional groups of the compatibilizer, such as anhydride groups. For this reason, the concentration of amine groups present in the polyamide (co)polymer is generally greater than 50 meq / kg, desirably greater than 60 meq / kg, and preferably greater than 70 meq / kg.

[0051] Suitable polyamide (co)polymers are available from a variety of manufacturers, including, but not limited to, Ascend, BASF, Bayer, DuPont, Invista, Nilit, Polytechnyl, and Shakespeare.

[0052] The amount of polyamide (co)polymer used in the composition of the present invention is an amount that interacts synergistically with polyphenylene ether and flame retardant to pass the GWIT test without generating flames. The amount of polyamide (co)polymer used is usually within the range of about 30 to about 80 parts by weight, desirably within the range of about 30 to about 70 parts by weight, and preferably within the range of about 32 to about 65 or about 35 to 45 parts by weight, based on 100 parts by weight of the total amount of the composition.

[0053] Polyphenylene Ether

[0054] Polyphenylene ether is an essential component of the composition of the present invention and is a polymer or copolymer having repeating structural units represented by the following formula:

[0055] [ka]

[0056] In the formula, O represents an oxygen atom, and each R independently represents hydrogen, a primary or secondary alkyl group having 1 to 7 carbon atoms, a phenyl group, an aminoalkyl group having 1 to 7 carbon atoms, or a hydrocarbyloxy group having 1 to 7 carbon atoms. Mixtures of polyphenylene ethers can be used.

[0057] Specific examples of polyphenylene ethers according to the present invention include poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), etc. Further examples include polyphenylene ether copolymers, such as copolymers of 2,6-dimethylphenol with another phenol (e.g., copolymers of 2,3,6-trimethylphenol, copolymers of 2-methyl-6-butylphenol).

[0058] Among these, particularly preferred polyphenylene ethers include poly(2,6-dimethyl-1,4-phenylene ether).

[0059] The polyphenylene ether is used in an amount sufficient to assist parts made from the composition in forming a charred layer, but below a level which would affect the flow of the composition during molding (making molding of small connectors very difficult).

[0060] The amount of polyphenylene ether present in the composition of the present invention is usually about 10 to about 55 parts by weight, desirably about 15 to about 50 parts by weight, and preferably about 20 to about 45 parts by weight, per 100 parts by weight of the total amount of the composition.

[0061] Compatibilizer

[0062] The composition of the present invention includes a compatibilizer to enhance the compatibility of polyamide with polyphenylene ether. The compatibilizer includes a first functional group that reacts with the polyphenylene ether and also includes a second functional group that can react with a functional group, such as an acid group, on the polyamide. The compatibilizer reduces the brittleness of the composition. For example, compatibilizers such as citric acid, fumaric acid, maleic anhydride, etc., react with polyphenylene ether. This functionalization effectively places an anhydride group at the end of the polyphenylene ether polymer chain. The anhydride group reacts with an amine group already available at the end of the polyamide polymer chain. As described herein above, the polyamide (co)polymers of the present invention have a desired concentration of amine end groups that help promote the reaction.

[0063] In a preferred embodiment, one of the functional groups is a carbon-carbon double bond or a carbon-carbon triple bond, and the other type is a carboxyl group, an acid anhydride, an epoxy group, an imide group, an amide group, an ester group, or an acid chloride, and equivalent functional groups.

[0064] Examples of the compatibilizer include, but are not limited to, maleic acid, maleic anhydride, maleic hydrazide, unsaturated dicarboxylic acids, fumaric acid, citric acid, citric anhydride, malic acid, and agaric acid, which may be used alone or in mixtures thereof.

[0065] Preferably, the compatibilizer is maleic acid, maleic anhydride, fumaric acid, citric acid, or citric acid anhydride, and most preferably maleic anhydride, citric acid, or citric acid anhydride.

[0066] The compatibilizer or a modifying compound of the compatibilizer reacts with a portion of the polyphenylene ether and a portion of the polyamide to produce a polyphenylene ether / polyamide block copolymer.

[0067] The polyphenylene ether / polyamide block copolymer is distributed at the interface between two (co)polymers in the polyamide / polyphenylene ether-containing composition to stabilize the morphology of the polymer composition. In particular, in the morphology of the polyamide / polyphenylene ether polymer composition in which the polyphenylene ether forms particles (dispersed phase) and the polyamide forms the matrix (continuous phase), the polyphenylene ether / polyamide block copolymer is considered to play an important role in controlling the particle size of the particles.

[0068] In the composition of the present invention, the compatibilizer is present in an amount of about 0.1 parts by weight to about 5 parts by weight, desirably about 0.2 to about 4 parts by weight, and preferably about 0.25 to about 3 parts by weight, based on 100 parts by weight of the total amount of the composition. If the content of the compatibilizer is too low, the impact resistance of the composition may not be significantly improved, and if the content is too high, the compatibilizer may not improve the impact resistance but may deteriorate other physical properties.

[0069] Flame retardant

[0070] The flame retardants utilized in the compositions of the present invention are halogen-free and phosphorus-containing compounds, preferably phosphinates.

[0071] Suitable phosphinates are represented by the following formula (I): These phosphinates are primarily monomeric compounds, but also include polymeric phosphinates, which are condensation products having a degree of condensation of 1 to 3 under some circumstances depending on the reaction conditions.

[0072] [ka]

[0073] In the formula, R1 and R2 are the same or different and each represents a linear or branched alkyl and / or aryl having 1 to 6 carbon atoms, or phenyl; M is calcium, magnesium, aluminum, zinc, bismuth, manganese, sodium, or potassium on the protonated nitrogen base; and m is 1, 2, or 3.

[0074] Specific examples of phosphinic acids used to form the phosphinate include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methanedi(methylphosphinic acid), benzene-1,4-(dimethylphosphinic acid), methylphenylphosphinic acid, diphenylphosphinic acid, and mixtures thereof.

[0075] The metal component is preferably at least one of calcium (ion), magnesium (ion), aluminum (ion), zinc (ion), bismuth (ion), manganese (ion), sodium (ion), potassium (ion), and protonated nitrogen base. At least one of calcium (ion), magnesium (ion), aluminum (ion), and zinc (ion) is more preferred.

[0076] Specific examples of phosphinates include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, and calcium methane di(methylphosphinate). , magnesium methane di(methylphosphinate), aluminum methane di(methylphosphinate), zinc methane di(methylphosphinate), calcium benzene-1,4-(dimethylphosphinate), magnesium benzene-1,4-(dimethylphosphinate), aluminum benzene-1,4-(dimethylphosphinate), zinc benzene-1,4-(dimethylphosphinate), calcium methylphenylphosphinate, magnesium methylphenylphosphinate, aluminum methylphenylphosphinate, zinc methylphenylphosphinate, calcium diphenylphosphinate, magnesium diphenylphosphinate, aluminum diphenylphosphinate, and zinc diphenylphosphinate.

[0077] Particularly preferred are calcium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, aluminum diethylphosphinate, and zinc diethylphosphinate.Of these, aluminum diethylphosphinate is particularly preferred.

[0078] The flame retardant is usually present in an amount of about 5 to about 35 parts by weight, desirably about 7.5 to about 30 parts by weight, and preferably about 10 to about 25 parts by weight, based on 100 parts by weight of the total amount of the composition.

[0079] Processing Aids

[0080] The composition of the present invention may also include various processing aids, each in an amount sufficient to obtain the desired properties, alone or in combination with other components. Such additives are well known to those skilled in the art and are described in various references on polymeric materials, see, for example, "Modern Plastics Handbook" and "Additives for Plastics Handbook". Various additives that may be included in the composition of the present invention include, but are not limited to, colorants, pigments, plasticizers, lubricants, UV stabilizers, light stabilizers, heat stabilizers, antioxidants, antistatic agents, biocides, surfactants, and combinations thereof.

[0081] Additives can be utilized in various amounts to impart desired properties to the composition, and therefore the range of any individual additive within the composition can vary.

[0082] No fillers used - selected embodiments

[0083] In an important aspect of the present invention, the inventors have discovered that compositions comprising the compatibilized blends of the described polyamides, polyphenylene ethers, and flame retardants can pass the Glow Wire Ignition Temperature (GWIT) IEC 60695-2-13 plaque test at temperatures up to 800° C. at a thickness of 2.0 mm without the presence of any fillers, without the formation of a flame. The ability to achieve a passing score for each test is highly surprising, since fillers are often used in blends of polyamides and polyphenylene ethers to reinforce such compositions and / or to impart flame retardant properties.

[0084] Therefore, in a preferred embodiment, the composition of the present invention does not contain any fillers, such as inorganic fillers, organic fillers, and bio-based fillers. Examples of fillers include, but are not limited to, glass (such as glass fiber and glass powder), clay (such as, but not limited to, bentonite, halloysite, montmorillonite, smectite, kaolin, etc.), metal powders, talc, titanium oxide, wollastonite, zinc oxide, carbon fiber, cellulose, graphite, lignin, and carbon nanotubes.

[0085] Halogen Free

[0086] The composition of the present invention does not contain any halogen-containing flame retardants or flame retardants, and preferably does not contain other components containing halogens. Thus, the term "halogen-free" and similar terms mean that the composition or component (e.g., referred to as a part, molded article, etc.) does not contain or is substantially free of halogens, i.e., the halogen content is less than 2,000 mg / kg as measured by ion chromatography. If the halogen content is less than this amount, it is believed that the performance of the composition and parts prepared therefrom will not be affected.

[0087] Composition Restrictions

[0088] Considering the excellent properties imparted by the components of the composition of the present invention, namely, polyamide, polyphenylene ether, flame retardant and compatibilizer, no additional compatibilizer or toughening agent is necessary or included in the composition.Furthermore, the composition does not include, for example, polystyrene-containing copolymers, including but not limited to, maleic anhydride grafted polystyrene-polyethylene-polybutylene-polystyrene linear triblock copolymers, maleic anhydride grafted polyphenylene ethers and polystyrene-polyethylene-polystyrene linear triblock copolymers.

[0089] Composition characteristics

[0090] The compositions of the present invention exhibit many desirable properties that are in high demand from manufacturers of various parts. They are flame retardant and meet stringent flame protection requirements that exceed the pass marks of the specific tests described herein. The compositions are also impact resistant and have desirable load deflection temperatures, tensile strengths, and flexural moduli and strengths.

[0091] Considering the ingredients utilized, the compositions are readily moldable by injection molding to produce molded articles having excellent appearance.

[0092] Product safety is important in every industry, especially in electrical and electronic applications. A number of different methods have been developed to measure the fire resistance and flammability of materials. Test methods include the use of both direct and indirect flames. The UL 94 standard utilizes a direct flame, which is applied directly to a vertically or horizontally mounted specimen under specified conditions. Glow wire tests are some of the most important indirect tests for electrical and electronic applications and are examples of indirect flame test methods.

[0093] Test results applying both direct and indirect flame techniques indicate the composition's tendency to resist flaming combustion or ignition and to self-extinguish if ignited, as well as its ability to stop the spread of fire by dripping.

[0094] The glow wire test is used to simulate a glowing wire in a component assembly that may occur due to an overloaded connection or an overheating component. The glow wire test method is included in the IEC 60695-2 series of standards. Generally, the glow wire test is performed by passing electricity through a heating element, i.e., a glow wire, to a predetermined temperature. The heating element is then inserted into the sample and pressed with the required force for the required period of time. The results are recorded and evaluated according to individual criteria. The glow wire test is performed on both the final product and on plaques or plates prepared from the desired composition.

[0095] GWEPT is an abbreviation for glow wire testing performed on finished products in accordance with the IEC 60695-2-11 standard. GWEPT testing is performed on actual parts molded from the desired composition. The compositions of the present invention, when molded into products or articles, pass the GWEPT test in accordance with the IEC 60695-2-11 standard and do not ignite or otherwise produce flames during the test procedure.

[0096] Additionally, test plaques or plates made from the compositions of the present invention pass the GWIT test, i.e., the Glow Wire Ignition Temperature test according to the IEC 60695-2-13 standard, and do not emit a flame at temperatures of 700°C, 750°C, and / or 800°C at a thickness of 2.0 mm.

[0097] Furthermore, the compositions of the present invention meet VO requirements at thicknesses between 0.4 mm and 3.0 mm when tested according to UL94 standards.

[0098] Additionally, when the compositions of the present invention are tested, they also meet the UL5 VA requirements at thicknesses between 1.5 mm and 3.0 mm.

[0099] Preparation method

[0100] The compositions of the present invention can be prepared utilizing standard processing equipment, such as extruders, such as single screw extruders and twin screw extruders; roller mills; kneaders; Brabenders; and Banbury mixers.

[0101] The processing temperature is selected so that the composition can be melt mixed below the decomposition points of the components, the temperature usually being within the range of about 275 to about 315°C.

[0102] In one embodiment, a multi-stage or multi-step process is utilized, the first stage involving reacting at least a portion of the polyphenylene ether with a compatibilizer. In this stage, the desired amounts of polyphenylene ether and compatibilizer are combined and mixed at a temperature preferably between 275-315°C. If carried out in an extruder, the polyphenylene ether and compatibilizer are combined at an upstream feed point. The polyamide is added downstream, preferably after allowing sufficient time for the polyphenylene ether and compatibilizer to react.

[0103] Other desired ingredients are added to the extrudate at desired feed points and the composition components are melt mixed and processed into the appropriate form before conversion to the final product, such as by injection molding. An injection molding machine was used to mold test specimens for material characterization. Typical melt processing temperatures are 290-320°C. EXAMPLES

[0104] The examples presented below are provided to illustrate the features of the compositions of the present invention and are not intended to limit the scope of the invention.

[0105] The following raw materials were used in the examples:

[0106] [Table 1]

[0107] The following protocol was used for the study.

[0108] [Table 2]

[0109] The following compositions were prepared according to the above procedures and tested as indicated in the table below.

[0110] [Table 3]

[0111] The examples shown in Table 1 demonstrate the novelty and inventive step of the compositions of the present invention. Comparative Example 1 shows that a composition containing polyamide and flame retardant can pass the GWIT test without emitting a flame at 650°C. One skilled in the art would expect that a composition containing more flame retardant would pass the test at a higher temperature. This is not the case as demonstrated by Comparative Examples 2 and 3, which contain 18.5% and 22% flame retardant, respectively.

[0112] The inventive examples demonstrate that a synergistic blend of polyphenylene ether and compatibilizer, along with polyamide and flame retardant, is necessary to pass the GWIT test without flaming at temperatures above 650° C. Each of the inventive formulations passes the described test at temperatures of at least 725° C. Examples 2C and 3C each pass with an excellent temperature of 825° C.

[0113] [Table 4]

[0114] Examples 4, 5 and 6 also demonstrate the inventive steps of the compositions of the present invention, utilizing different polyamides and lubricants with varying levels of polyphenylene ether, compatibilizers and flame retardants.

[0115] For the avoidance of doubt, the compositions, articles and methods of the present invention encompass all possible combinations of the components, including the various ranges of the components disclosed herein. It is further noted that the term "comprising" does not exclude the presence of other elements. However, it is to be understood that a description of a product comprising certain components also discloses a product consisting of these components. Similarly, a description of a process comprising certain steps also discloses a process consisting of these steps.

[0116] While in accordance with the patent statutes, the best mode and preferred embodiment have been set forth, the scope of the invention is not limited thereto, but rather by the appended claims.

Claims

1. A halogen-free, flame-resistant, compatibilized polyamide and polyphenylene ether blend composition, A polyamide (co)polymer that is present in an amount of about 30 to about 80 parts by weight based on 100 parts by weight of the composition, is an aliphatic (co)polymer, and is present as a continuous phase in the composition; About 15 to about 50 parts by weight of polyphenylene ether based on 100 parts by weight of the total amount of the composition; i) the polyamide (co)polymer, ii) the polyphenylene ether, and iii) A compatibilizer having two different types of functional groups including a first functional group capable of reacting with the polyamide (co)polymer of i) and a second functional group capable of reacting with the polyphenylene ether of ii) A block copolymer compatibilizer derived from, The compatibilizer of the block copolymer compatibilizer is present in an amount of about 0.1 to about 5 parts by weight based on 100 parts by weight of the composition, the block copolymer compatibilizer; A flame retardant which is a phosphinate present in an amount of about 5 to about 35 parts by weight based on 100 parts by weight of the composition; comprising, The composition does not contain a halogen-containing flame retardant, Plaques or plates prepared from the composition are 2.0 mm thick, do not emit flames at 700 °C, and pass a test conforming to the GWIT IEC60695-2-13 standard, Blend composition.

2. The blend according to claim 1, wherein the polyamide (co)polymer is one or more of polyamide 6; polyamide 6,6; polyamide 4,6; polyamide 11; polyamide 12; polyamide 6,10; polyamide 6,12; polyamide 6 / 6,6; and polyamide 6 / 6,12.

3. The flame retardant is one or more of aluminum diethylphosphinate, zinc diethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum dipropylphosphinate, isopropylphosphinate, aluminum butylphosphinate, aluminum methylethylphosphinate, and aluminum phenylphosphinate, the blend according to claim 2.

4. The blend according to any one of claims 1 or 3, wherein the composition does not contain a filler.

5. The blend according to claim 1, wherein the plaque or plate prepared from the composition does not emit a flame at 750 °C with a thickness of 2.0 mm and passes the test according to the GWIT IEC60695-2-13 standard.

6. The blend according to claim 5, wherein the plaque or plate prepared from the composition does not emit a flame at 800 °C with a thickness of 2.0 mm and passes the test according to the GWIT IEC60695-2-13 standard.

7. The polyamide (co)polymer is present in an amount of about 30 to about 70 parts by weight based on 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 15 to about 50 parts by weight based on 100 parts by weight of the total amount of the composition, the compatibilizer is present in an amount of about 0.2 to about 4 parts by weight based on 100 parts by weight of the composition, and the flame retardant is present in an amount of about 7.5 to about 30 parts by weight based on 100 parts by weight of the composition, the blend according to claim 1.

8. The polyamide (co)polymer is present in an amount of about 32 to about 65 parts by weight based on 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 20 to about 45 parts by weight based on 100 parts by weight of the total amount of the composition, the compatibilizer is present in an amount of about 0.25 to about 3 parts by weight based on 100 parts by weight of the composition, and the flame retardant is present in an amount of about 10 to about 25 parts by weight based on 100 parts by weight of the composition, the blend according to claim 7.

9. The blend according to claim 1, wherein the composition further comprises a lubricant.

10. The blend according to claim 1, wherein the polyphenylene ether is present as a discontinuous phase in the blend.

11. The blend according to claim 10, wherein the polyphenylene ether is one or more of poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), and a copolymer of 2,6-dimethylphenol and another phenol.

12. The blend according to claim 1, wherein the compatibilizer is one or more of maleic acid, maleic anhydride, fumaric acid, citric acid, and citric anhydride.

13. The blend according to claim 1, wherein the first functional group is one or more of a carbon-carbon double bond and a carbon-carbon triple bond, and the second functional group is one or more of a carboxyl group, an acid anhydride, an epoxy group, an amide group, an ester group, and an acid chloride.

14. The blend according to claim 2, wherein the compatibilizer is one or more of maleic acid, maleic anhydride, fumaric acid, citric acid, or citric anhydride.

15. The blend according to claim 1, wherein the polyamide (co)polymer has an amine group concentration of 50 meq / kg or more.

16. The blend according to claim 15, wherein the polyamide (co)polymer has an amine group concentration of 60 meq / kg or more.

17. The blend according to claim 14, wherein the polyamide (co)polymer has an amine group concentration of 50 meq / kg or more.

18. A method for forming the blend according to claim 1, comprising: Before reacting a portion of the polyamide copolymer, reacting a portion of the polyphenylene ether with the compatibilizer to form the block copolymer compatibilizer.

19. The method according to claim 18, wherein the blend is extruded, the compatibilizer and a portion of the polyphenylene ether are combined at an upstream feed position, and after the compatibilizer and the portion of the polyphenylene ether have reacted, the polyamide (co)polymer is added downstream.

20. The polyphenylene ether is one or more of poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), and a copolymer of 2,6-dimethylphenol and another phenol, The blend according to claim 4, wherein the compatibilizer is one or more of maleic acid, maleic anhydride, fumaric acid, citric acid, and citric anhydride.

21. The polyamide (co)polymer is present in an amount of about 30 to about 70 parts by weight based on 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 15 to about 50 parts by weight based on 100 parts by weight of the total amount of the composition, the compatibilizer is present in an amount of about 0.2 to about 4 parts by weight based on 100 parts by weight of the composition, and the flame retardant is present in an amount of about 7.5 to about 30 parts by weight based on 100 parts by weight of the composition.

22. The polyamide (co)polymer is present in an amount of about 32 to about 65 parts by weight based on 100 parts by weight of the composition, the polyphenylene ether is present in an amount of about 20 to about 45 parts by weight based on 100 parts by weight of the total amount of the composition, the compatibilizer is present in an amount of about 0.25 to about 3 parts by weight based on 100 parts by weight of the composition, and the flame retardant is present in an amount of about 10 to about 25 parts by weight based on 100 parts by weight of the composition.

Images