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JP-2026075617-A - Flame-retardant polyamide molding material

JP2026075617AJP 2026075617 AJP2026075617 AJP 2026075617AJP-2026075617-A

Abstract

[Problem] To provide a flame-retardant polyamide molding material, particularly for railway applications. [Solution] Preferably, a flame-retardant polyamide molding material consisting of the following: A) Semicrystalline aliphatic polyamides containing 34–88% by weight, with a C/N ratio of at least 8; B) A flame retardant consisting of B1 and B2 in an amount of 6 to 21% by weight, B1) 50 to 100% by weight of at least one metal phosphinate; B2) 0 to 50% by weight of at least one flame retardant synergistic agent and/or at least one nitrogen and phosphorus-containing flame retardant; Here, the sum of components B1 and B2 is 100% by weight of component B; C) 1-10% by weight of graphite; D) 0-25% by weight of polyamide elastomer; E) 0-10% by weight of plasticizer; F) 0-10% by weight of polyolefin; G) 0-5% by weight of additives other than A-F; [Selection Diagram] None

Inventors

  • エティエンヌ エプリ

Assignees

  • エムス ヒェミー アーゲー

Dates

Publication Date
20260508
Application Date
20251021
Priority Date
20241022

Claims (15)

  1. A polyamide molding material containing, preferably comprising, the following: A. Semicrystalline aliphatic polyamides containing 34–88% by weight, with a C/N ratio of at least 8; B A flame retardant consisting of B1 and B2 in an amount of 6 to 21% by weight, B1 50 to 100% by weight of at least one metal phosphinate; B2 0 to 50% by weight of at least one flame retardant synergistic agent and/or at least one nitrogen and phosphorus-containing flame retardant; Here, the sum of components B1 and B2 is 100% by weight of component B; C 1-10% by weight of graphite; D 0-25% by weight of polyamide elastomer; E 0-10% by weight of plasticizer; F 0-10% by weight of polyolefin; G: 0-5% by weight of additives different from A-F; Here, the sum of the weight percentages of components D to F is 5 to 30% by weight relative to the sum of the weight percentages of components A to G, and the sum of the weight percentages of components A to G is 100% by weight.
  2. Polyamide A is Selected from semicrystalline aliphatic polyamides having a C/N ratio of at least 10, preferably 10 to 13; or selected from the group consisting of PA610, PA612, PA614, PA616, PA1010, PA1012, PA1014, PA1016, PA11, PA12, or mixtures thereof; Alternatively, a selection will be made from the group consisting of PA1010, PA1012, PA11, PA12 and mixtures thereof; and/or, characterized in that, when measured in a solution prepared by dissolving 0.5 g of polymer in 100 ml of m-cresol at 20°C in accordance with DIN EN ISO 307:2007, the solution viscosity is in the range of η rel = 1.5 to 2.8, preferably in the range of η rel = 1.6 to 2.3. The polyamide molding material according to claim 1.
  3. The proportion of component B is in the range of 7 to 16% by weight, preferably 8 to 14% by weight, relative to components A to G; and/or, the polyamide molding material according to any one of the preceding claims, characterized in that component B consists of 55 to 100% by weight of B1 and 0 to 45% by weight of B2, preferably 60 to 100% by weight of B1 and 0 to 40% by weight of B2, particularly preferably 75 to 98% by weight of B1 and 2 to 25% by weight of B2, and even more preferably 100% by weight of B1 and 0% by weight of B2, wherein the sum of the weight percentages of B1 and B2 is 100% by weight of component B.
  4. At least one metal phosphinate of component B1 is selected as a phosphinate and/or diphosphinate, preferably a phosphinate of general formula (I) and/or general formula (II) and/or a polymer thereof. (In the formula, R1 and R2 are the same or different, preferably C1-C8-alkyl (linear or branched) and/or aryl; R3 is a C1-C10-alkylene (linear or branched), C6-C10-arylene, -alkylarylene, or arylalkylene; M is a metal ion belonging to the second or third main or subgroup of the periodic table; m is either 2 or 3; n is either 1 or 3; x is either 1 or 2; (Preferably Al, Ca, and Zn are used as the metal ion M.) A polyamide molding material according to any one of the preceding claims, characterized in that
  5. The polyamide molding material according to any one of the preceding claims, characterized in that the proportion of component C is in the range of 2 to 8% by weight, preferably 3 to 7% by weight, relative to the sum of the weight percentages of components A to G.
  6. The polyamide elastomer of component D has a hard segment based on polyamide PA610, PA612, PA614, PA616, PA1010, PA1012, PA1014, PA1016, PA11, PA12 and a soft segment based on the following (preferably only the following): Polyetherdiols based on (preferably based on only) at least one constituent unit selected from the group consisting of ethylene oxide, propylene oxide, tetrahydrofuran, or mixtures thereof, and/or polyetherdiamines based on dimerized fatty acids having 20 to 44 carbon atoms, and/or at least one constituent unit selected from the group consisting of ethylene oxide, propylene oxide, tetrahydrofuran, or mixtures thereof (preferably based on only these); Here, preferably, the polyamide hard segment has a number-average molar mass in the range of 500 to 10,000 g/mol, preferably 700 to 5,000 g/mol, and particularly preferably 750 to 3,000 g/mol; and/or, the soft segment has a number-average molar mass in the range of 200 to 4000 g/mol, preferably 200 to 3000 g/mol, and particularly preferably 300 to 2500 g/mol; and/or, therein, the proportion of polyamide hard segments is 45 to 95% by weight, preferably 50 to 80% by weight, and the proportion of soft segments is 5 to 55% by weight, preferably 20 to 50% by weight, relative to 100% by weight of component D; and/or, component D preferably does not contain an ester bond; and/or, the polyamide molding material according to any one of the preceding claims, characterized in that the proportion of component D is in the range of 0 to 20% by weight, preferably 6 to 18% by weight or 8 to 18% by weight, relative to the sum of the weight percentages of components A to G.
  7. The proportion of plasticizer in component E is in the range of 0 to 7% by weight, preferably 1 to 6% by weight or 1 to 5% by weight, relative to the sum of the weight percentages of components A to G; and/or, the polyamide molding material according to any one of the preceding claims, characterized in that the plasticizer of component E is selected from the group consisting of aryl sulfonamide having 2 to 12 carbon atoms, p-hydroxybenzoic acid ester having 2 to 20 carbon atoms in the alcohol component, organic phosphonate or phosphate, and silicone oil.
  8. A polyamide molding material according to any one of the preceding claims, characterized in that component E is silicone oil.
  9. The proportion of component F is in the range of 0 to 7% by weight, preferably 1 to 6% by weight or 1 to 5% by weight, relative to the sum of the weight percentages of components A to G; and/or, at least one polyolefin of component F is composed of at least one or a combination of the following constituent units: ethylene, propylene, butylene, acrylate, methacrylate, acrylic acid, methacrylic acid, maleic anhydride, glycidyl methacrylate, diene, particularly butadiene and/or isoprene, preferably as a copolymer, particularly preferably as a terpolymer; and/or, at least one polyolefin of component F is selected from the group consisting of ethylene-propylene rubber, ethylene-propylene-diene rubber, styrene-containing elastomers, particularly SEBS, SBS, SEPS, acrylate rubber, nitrile rubber, and silicone rubber; and/or, at least one polyolefin of component F is functionalized with maleic anhydride, acrylic acid and/or glycidyl methacrylate, and preferably has a grafting degree in the range of 0.05 to 10% by weight; and/or, the polyamide molding material according to any one of the preceding claims, characterized in that component F is a polyolefin ionomer in which the carboxyl groups present are partially or completely neutralized with a metal base.
  10. A polyamide molding material according to any one of the preceding claims, characterized in that the proportion of component G is in the range of 0 to 2.0% by weight, preferably 0.1 to 2.0% by weight, relative to the sum of the weight percentages of components A to G.
  11. A polyamide molding material according to any one of the preceding claims, characterized by comprising the following: A. Polyamide selected from the group consisting of PA1010, PA1012, PA11, PA12, or mixtures thereof, in an amount of 34 to 88% by weight; B A flame retardant consisting of B1 and B2 in an amount of 6 to 21% by weight, B1 50 to 100% by weight of at least one metal phosphinate; B2 0 to 50% by weight of at least one flame retardant synergistic agent and/or at least one nitrogen and phosphorus-containing flame retardant; Here, the sum of components B1 and B2 is 100% by weight of component B; C 1-10% by weight of graphite; D is a polyamide elastomer in a weight of 0 to 25%. PA1010, PA1012, PA11 or PA12 polyamide hard segments, It consists of a soft segment based on (preferably based solely on) a polyetherdiol composed of at least one constituent unit selected from the group consisting of ethylene oxide, propylene oxide, and tetrahydrofuran; Here, the polyamide elastomer preferably does not contain ester bonds; E 0 to 10% by weight of a plasticizer selected as N-butylbenzenesulfonamide and/or silicone oil; F 0 to 10% by weight of polyolefin, selected as a copolymer composed of at least one or a combination of the following constituent units: ethylene, propylene, butylene, acrylate, methacrylate, acrylic acid, methacrylic acid (preferably functionalized with maleic anhydride) and/or selected as a polyolefin ionomer; G: 0-5% by weight of additives different from A through F; Here, the sum of components D to F is between 5% and 30% by weight of the sum of the weight percentages of components A to G, and the sum of the weight percentages of components A to G is 100% by weight.
  12. A method for producing a polyamide molding material according to any one of the preceding claims, characterized in that component A and components B to G, or preferably components C, D, F, and G, are mixed simultaneously, wherein the mixing is preferably carried out at a temperature range of 240 to 300°C, particularly 250 to 290°C, the plasticizer E is added to the mixture individually as a liquid or pre-mixed with component A as granules, and the flame retardant B is mixed into the remaining mixture, which is already in a molten state, preferably as a separate powder.
  13. A component comprising a polyamide molded material as described in any one of claims 1 to 11, preferably manufactured by the method described in claim 12, and particularly for fire protection applications in the railway sector, preferably a coating, cover, film, profile, tube, corrugated tube, hollow body, seal, panel, bracket, housing, sheath, electrical and electronic component, preferably a plug and fan (preferably approved under DIN EN 45545).
  14. A method for manufacturing the part described in claim 13, preferably characterized by molding the polyamide molding material described in any one of claims 1 to 11 into a part by extrusion molding, extrusion blow molding, injection molding, or overmolding.
  15. A use of the polyamide molding material according to any one of claims 1 to 11, preferably manufactured by the method described in claim 12, for the purpose of manufacturing the part according to claim 13.

Description

This invention relates to a halogen-free, flame-retardant polyamide molding material based on long-chain aliphatic polyamides, which has a high LOI value and good processing characteristics in the extrusion process. The invention further relates to a method for producing the polyamide molding material and its use. Conventional technology Flame-retardant polyamide molding materials are known in themselves from the prior art. A polyamide molding material having a matrix of polyamide 12, further containing a flame retardant and a plasticizer, is known from EP-A-3 127 937. This molding material may also contain additional additives and polyolefins. In addition to polyamide 12, a polyamide elastomer based on polyamide 12 may be included in the matrix. This molding material has been proposed for flexible components, particularly for flame-retardant applications in the railway sector. The examples do not include graphite, nor is it disclosed that the use of graphite with low concentrations of flame retardant in this molding material may increase the LOI (Liquidity of Inclusion). EP-A-3502186 describes a plasticized flame-retardant thermoplastic polyamide molding material having particularly good processing properties, good flame retardancy and good flexibility, and, for example, resistance to fuel washout, as well as the use of such polyamide molding materials. The material is suitable, for example, as a material for fuel lines (fuel piping) in the automotive sector, or for generally flexible molded articles, including lines particularly for the railway sector. This polyamide is based on long-chain aliphatic dicarboxylic acids. Again, there is no mention of graphite. From EP-A-2 410 020, its use in manufacturing unreinforced, halogen-free, flame-retardant polyamide molding materials and electrical and/or electronic components is known, with particular emphasis on its suitability for soldering processes. Only terephthalic acid-based partially aromatic polyamides are considered as the polyamide base. Therefore, the object of the present invention is to provide a novel, preferably unreinforced, polyamide molding material having sufficient flexibility, which is flame-retardant and halogen-free, has a high LOI (limiting oxygen index), has sufficient notched impact strength at low temperatures, and exhibits good processing characteristics, particularly in extrusion or extrusion blow molding processes. The molding material according to the present invention should have an LOI value greater than 32%, preferably at least 34%, and particularly preferably at least 36%, as determined by DIN EN ISO 4589-2:2017. This problem is solved by the molding material defined in the claims, a method for manufacturing the molding material defined in the claims, a component made from such molding material, and the use of the molding material as indicated in the claims. Therefore, the present invention proposes a halogen-free flame-retardant polyamide molding material based on semi-crystalline aliphatic polyamide, which is particularly suitable for railway applications. It has been surprisingly found that a halogen-free flame retardant based on metal phosphinate can be advantageously used in combination with graphite for flexible polyamide molding materials comprising at least one of the following components: a plasticizer, an impact modifier, and a polyamide elastomer. The proposed molding material is characterized in particular by having an LOI greater than 32%, preferably at least 34%, and especially preferably at least 36%, as determined according to DIN EN ISO 4589-2:2017; a tensile modulus in the range of 500 to 1500 MPa as determined according to ISO 527:2012; an elongation at break greater than 100%, as determined according to ISO 527:2012; and a notched impact strength at -45°C, as determined according to ISO 179/1(2023) or ISO 179/2(2020), preferably at least 4 kJ/ m² . Specifically, the present invention relates to a polyamide molding material comprising, preferably, the following: A. Semicrystalline aliphatic polyamides containing 34–88% by weight, with a C/N ratio of at least 8; B A flame retardant comprising 6 to 21% by weight, the following B1 and B2: B1 50 to 100% by weight of at least one metal phosphinate; B2 0 to 50% by weight of at least one flame retardant synergistic agent and/or at least one nitrogen and phosphorus-containing flame retardant; Here, the sum of components B1 and B2 is 100% by weight of component B; C 1-10% by weight of graphite; D 0-25% by weight of polyamide elastomer; E 0-10% by weight of plasticizer; F 0-10% by weight of polyolefin; G: An additive in an amount of 0-5% by weight, which is different from additives A-F; Here, the sum of the weight percentages of components D to F is 5 to 30% by weight relative to the sum of the weight percentages of components A to G, and the sum of the weight percentages of components A to G is 100% by weight. The polyamide molding material according to the present inv