POLYAMIDE MOULDING COMPOSITION AND MOULDED ARTICLE MADE THEREFROM

Abstract

The present invention refers to a polyamide moulding composition consisting of the following components: (A) 30 to 79.7% by weight of at least one partially crystalline polyamide consisting of at least one diamine and at least one aromatic dicarboxylic acid, whereupon the at least one diamine has 4 to 20 carbon atoms and is selected from a group of diamines consisting of linear aliphatic diamines, branched aliphatic diamines, cycloaliphatic diamines and araliphatic diamines, (B) 0 to 10% by weight of at least one polyamide different from component (A) (C) 20 to 55% by weight of at least one fibrous reinforcing agent, (D) 0.2 to 2.0% by weight of nigrosine, (E) 0.1 to 3.0% by weight of at least one heat stabilizer, (F) 0 to 10% by weight of a at least one additive, whereby the entirety of components (A) to (F) add up to 100% by weight.

Claims

1-19. (canceled)

20. A polyamide moulding composition consisting of the following components: (A) 30 to 77.6% by weight of at least one partially crystalline polyamide consisting of at least one diamine and at least one aromatic dicarboxylic acid, wherein the at least one diamine has 4 to 20 carbon atoms and is selected from a group of diamines consisting of linear aliphatic diamines, branched aliphatic diamines, cycloaliphatic diamines, and araliphatic diamines, (B) 2.0 to 10% by weight of at least one polyamide different from component (A), (C) 20 to 55% by weight of at least one fibrous reinforcing agent, (D) 0.3 to 2.0% by weight of at least one azine dye, (E) 0.1 to 3.0% by weight of at least one heat stabilizer, and (F) 0 to 10% by weight of a at least one additive, different from components (A)-(E), components (A) to (F) adding up to 100% by weight.

21. The polyamide moulding composition according to claim 20, wherein components (A) to (F) are present in the following amounts: (A) 32.5 to 72.5% by weight of the at least one partially crystalline polyamide, (B) 2.0 to 7.0% by weight of at least one polyamide different from component (A), (C) 25.0 to 50.0% by weight of at least one fibrous reinforcing agent, (D) 0.3 to 1.5% by weight of at least one azine dye, (E) 0.2 to 2.0% by weight of at least one heat stabilizer, and (F) 0 to 7.0% by weight of at least one additive, components (A) to (F) adding up to 100% by weight.

22. The polyamide moulding composition according to claim 20, wherein the partially crystalline polyamide (A) has a melting point of at least 280 C. as measured according to DIN EN ISO 11357-3:2013-04 and/or a solution viscosity .sub.rel as measured according to DIN EN ISO 307:2013-08 on solutions of 0.5 g polymer in 100 mL m-cresol at a temperature of 20 C., of a maximum of 2.60.

23. The polyamide moulding composition according to claim 20, wherein the at least one partially crystalline polyamide (A) is produced by polycondensation of a) 30-100 mol % terephthalic acid and/or naphthalene dicarboxylic acid, 0-70 mol % of at least one aliphatic dicarboxylic acid having 6-12 carbon atoms, 0-70 mol % of at least one cycloaliphatic dicarboxylic acid having 8-20 carbon atoms, and/or 0-50 mol % isophthalic acid, with respect to the total amount of the dicarboxylic acids, b) 80-100 mol % of at least one linear or branched aliphatic diamine having 4-18 carbon atoms and 0-20 mol % of at least one cycloaliphatic diamine, and/or 0-20 mol % of at least one araliphatic diamine, with respect to the total amount of the diamines, and optionally c) aminocarboxylic acids and/or lactams, each having 6-12 carbon atoms.

24. The polyamide moulding composition according to claim 20, wherein the at least one semiaromatic polyamide (A) is formed from: a) at least 30 mol % terephthalic acid, b) at least 80 mol % aliphatic diamines having 4-20 carbon atoms, and optionally c) lactams and/or aminocarboxylic acids each having 6-12 carbon atoms.

25. The polyamide moulding composition according to claim 20, wherein the at least one semiaromatic polyamide (A) is selected from the group consisting of PA 4T/4I, PA 4T/6I, PA 5T/5I, PA 6T/6, PA 6T/6I, PA 6T/6I/6, PA 6T/6I/66, PA 6T/6I/610, PA 6T/6I/612, PA 6T/66, PA 6T/610, PA 6T/612, PA 6T/10T, PA 6T/10I, PA 9T, PA 9MT wherein M=Methyloctanediamine, PA 10T, PA 12T, PA 10T/10I, PA 10T/106, PA 10T/12, PA 10T/11, PA 6T/9T, PA 6T/12T, PA 6T/10T/6I, PA 6T/6I/6, and PA 6T/6I/12.

26. The polyamide moulding composition according to claim 20, wherein the at least one semiaromatic polyamide (A) is selected from the group consisting of PA 6T/6I having 50-80 mol % hexamethyleneterephthalamide units and 20-50 mol % hexamethyleneisophthalamide units, PA 6T/66 having 50-65 mol % hexamethyleneterephthalamide units and 35-50 mol % hexamethyleneadipamide units, a semicrystalline polyamide 6T/6I/612/X having 60-75 wt.-% hexamethyleneterephthalamide units (6T), 20-35 wt.-% hexamethyleneisophthalamide units (61), 3-15 wt.-% hexamethylenedodecanamide units (612) and 0-5 wt.-% units of X selected from the following units 66, 68, 69, 610, 6 or a mixture thereof, wherein the sum of the components is 100 wt.-% of the polyamide 6T/6I/612/X, a semicrystalline polyamide 6T/6FX having 60-75 wt.-% hexamethyleneterephthalamide units (6T), 20-35 wt.-% hexamethyleneisophthalamide units (6I), 5-20 wt.-% units X selected from the following units 66, 68, 69, 610, 612, 6 or a mixture thereof, wherein the sum of the components is 100 wt.-% of the polyamide 6T/6I/X, a semicrystalline polyamide prepared from at least 50 mol % terephthalic acid and a maximum of 50 mol % isophthalic acid and a mixture of at least two diamines chosen from the group consisting of hexamethylenediamine, nonanediamine, methyloctanediamine, and decanediamine; a semicrystalline polyamide prepared from at least 50 mol % terephthalic acid and a maximum of 50 mol % dodecanedioic acid and a mixture of at least two diamines chosen from the group hexamethylenediamine, nonanediamine, methyloctanediamine and decanediamine, PA 6T/10T having 10-60 mol % hexamethyleneterephthalamide (6T) and 40-90 mol % decamethyleneterephthalamide (10T) units, PA 6T/10T/6I having 50-90 mol % hexamethyleneterephthalamide units (6T), and 5-45 mol % hexamethyleneterephthalamide units (6I), and 5-45 mol % decamethyleneterephthalamide (10T) units, and PA 6T/6I/6 having 60-85 mol % hexamethyleneterephthalamide units (6T) and 15-40 mol % hexamethyleneisophthalamide units (6I), which additionally contains 5-15 wt % caprolactam.

27. The polyamide moulding composition according to claim 20, wherein the at least one polyamide of component (B) is selected from the group consisting of partially crystalline polyamides (B1) based on aliphatic or araliphatic diamines and aliphatic dicarboxylic acids and amorphous polyamides (B2) based on cycloaliphatic or aromatic dicarboxylic aids or diamines.

28. The polyamide moulding composition according to claim 20, wherein the at least one fibrous reinforcing agent is selected from the group consisting of glass fibers and carbon fibers.

29. The polyamide moulding composition according to claim 20, wherein the fibres are selected from the group consisting of short fibres with a length of 0.1-50 mm or endless fibres, fibers with a diameter of 5-40 m, fibers with a circular or noncircular cross section, and a combination of the aforementioned fibers.

30. The polyamide moulding composition according to claim 20, wherein the at least one azine dye is selected from the group consisting of nigrosines and indulines.

31. The polyamide moulding composition according to claim 20, wherein the at least one azine dye is a powder with a volume average particle size 50 (Dv50) according to ISO 13320:2009 of 5 to 20 m.

32. The polyamide moulding composition according to claim 20, wherein the at least one heat stabilizer is selected from the group consisting of a) compounds of mono- or divalent copper, b) stabilizers based on secondary aromatic amines, c) stabilizers based on sterically hindered phenols, d) phosphites and phosphonites, e) metal salts or metal oxides, and f) mixtures of the above-mentioned stabilizers.

33. The polyamide moulding composition according to claim 20, wherein the at least one additive is selected from the group consisting of UV- and light-stabilisers, lubricants, colouring- and marking materials, inorganic pigments, organic pigments, IR absorbers, antistatic agents, antiblocking agents, crystal-growth inhibitors, condensation catalysts, chain extenders, defoamers, chain-lengthening additives, conductivity additives, carbon black, graphite, carbon nanotubes, mould-release agents, separating agents, flame retardants, non-halogen-containing flame retardants, anti-dripping-agents, impact modifiers, optical brighteners, photochromic additives, and metallic pigments.

34. The polyamide moulding composition according to claim 20, whose deflection temperature under load (HDT (A), 1.80 MPa) according to DIN EN ISO 75-1:2013 and DIN EN ISO 75-2:2013 is at least 250 C.

35. The polyamide moulding composition according to claim 20, which is free from nucleating agents, particulate fillers or non-fibrous inorganic fillers, and/or carbon black.

36. A method for producing a moulded article in which a polyamide moulding composition according to claim 20 is transformed into the moulded article by assisted injection moulding.

37. A moulded article comprising a polyamide moulding composition according to claim 20.

38. The moulded article according to claim 37, wherein at least a part of a surface has a roughness measured according to DIN EN ISO 4287 (2010 July) with Ra value less than 4.2 m and/or Rz value less than 25 m.

Description

[0203] The effect of the invention further is demonstrated in the following figures.

[0204] FIG. 1 represents the microscope photograph of a surface of a moulded article, formed from a composition of example 8 (tab. 2).

[0205] As can be seen from the figure, virtually no glas fibers at all are present at the surface. The surface is fully covered by the polyamide matrix material. Therefore, a high surface smoothness can be realized.

[0206] In contrast, FIG. 2 shows a microscope photograph of the surface of a reference sample, made from comparative example 4 (tab. 3).

[0207] As can be seen, a numerous isolated glass fibers, which are not fully integrated into the polyamide matrix are present at the surface. These more or less exposed glass fibers contribute to the reduced surface smoothness, furthermore, these exposed glass fibers are subject to abrasion or extraction (glass fiber debonding).

[0208] In comparison to the inventive examples CEx.9 and 10 are cearly inferior with respect to heat deflection temperature, hydrolytic resistance and quality of the inner surface.