POLYAMIDE MOLDING COMPOSITION FOR HIGH-GLOSS APPLICATIONS

Abstract

Described herein is a thermoplastic molding material including a) a mixture of 100 parts by weight of polyamide including aliphatic unbranched C.sub.10-12-foundational units and 5 to 100 parts by weight of polyamide 6 and/or polyamide 6/6,6 as component A), and b) 0% to 30% by weight, based on component A), of further additives as component

B), including 0% to 20% by weight, based on component A), of inorganic fillers and reinforcing materials.

Claims

1. A thermoplastic molding material composed of a) a mixture of 100 parts by weight of polyamide comprising aliphatic unbranched C.sub.10-12-foundational units and 5 to 100 parts by weight of polyamide 6 and/or polyamide 6/6,6 as component A), and b) 0% to 10% by weight, based on component A), of further additives as component B), including 0% by weight, based on component A), of glass fibers, wherein the polyamide of component A) comprising aliphatic unbranched C.sub.10-12-foundational units is polyamide 6,10.

2. The thermoplastic molding material according to claim 1, wherein component A) comprises 10 to 80 parts by weight of polyamide 6 and/or polyamide 6/6,6.

3. The thermoplastic molding material according to claim 1, wherein component B) comprises 0.1% to 3% by weight, based on component A), of carbon black.

4. The thermoplastic molding material according to claim 1, wherein component B) comprises 0.01% to 1% by weight, based on component A), of lubricants.

5. The thermoplastic molding material according to claim 1, wherein it comprises 0% by weight, based on component A), of inorganic fillers and reinforcing materials.

6. The thermoplastic molding material according to claim 1, wherein it has a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of 4 or more.

7. A process for producing molding materials according to claim 1, wherein the components A) and B) are mixed with one another.

8. A method of using the molding materials according to claim 1, the method comprising using the molding materials for producing films or shaped articles.

9. A film or shaped article made of a molding material according to claim 1.

10. A method of using mixtures of 100 parts by weight of polyamide comprising aliphatic unbranched C.sub.10-12-foundational units and 5 to 100 parts by weight of polyamide 6 and/or polyamide 6/6,6 in shaped articles, the method comprising using the mixtures for improving gloss properties upon exposure of the shaped articles to road salt and/or automatic carwashes.

11. The method of use according to claim 10, wherein the polyamide of component A) comprising aliphatic unbranched C.sub.10-12-foundational units is selected from the group consisting of polyamide 6,10, polyamide 6,12, polyamide 12,12, polyamide 11, polyamide 12 and mixtures thereof.

12. The method of use according to claim 10, wherein the shaped articles have a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of at least 4.

13. The thermoplastic molding material according to claim 1, wherein it has a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of 4 to 5.

14. The thermoplastic molding material according to claim 1, wherein it has a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of 5.

15. The method of use according to claim 10, wherein the shaped articles have a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of 4 to 5.

16. The method of use according to claim 10, wherein the shaped articles have a gray scale, determined according to ISO 105 A02 after testing according to DBL 5416, 7.3, of 5.

Description

EXAMPLES

[0103] Materials:

TABLE-US-00004 PA 6,10: Zytel ® RS LC3060 NC010 from DuPont PA 6: Ultramid ® B27 from BASF, VN = 150 mL/g PA 66/6: copolymer comprising 85% by weight of PA66, 15% by weight of PA6, VN = 145 mL/g, PA 66: Ultramid ® A27 from BASF, VN = 150 mL/g SAN: Luran ® HH 120 SPF50 from Styrolution Carbon black: Black Pearls ® 880 from Cabot Calcium stearate: Ceasit ® from Baerlocher

[0104] Characterization Methods:

[0105] Notched impact strength according to ISO 179/1eU (2018 version);

[0106] Gloss determination according to DIN EN ISO 2813 (2015);

[0107] Road salt resistance according to Daimler standard DBL 5416, 7.3 (2011-02);

[0108] Automatic carwash resistance according to DIN EN ISO 20566 (2013-06): [0109] Washing brush: diameter 1000 mm, width 400 mm, material polyethylene, x-shaped and spliced, bristle thickness 0.8 mm, bristle length 440 mm, immersion depth 100 mm, brush speed 120 rpm [0110] Spray nozzles: made of stainless steel, opening angle 60°, water flow rate 2.2 L/min at 300 kPas [0111] Advancement rate of sample table: (5±0.2) m/min [0112] Washing solution: suspension of 1.5 g quartz flour (average particle size 24 μm) per liter of drinking water [0113] Room climate: air-conditioned room at (23±2)° C. and atmospheric humidity (50±5)% [0114] Performing the test: The samples were conditioned for 16 hours under standard conditions of temperature and humidity. The zero values for gloss were then determined. The sample plates were then placed on the sample table and subjected to ten double strokes. The sample plates were subsequently cleaned with cold water, then cleaned with a suitable solvent (for example ethanol) and a cloth and flashed off for 10 minutes. The gloss values for the treated samples were then measured

[0115] Gray scale determination according to ISO 105 A02 (1993-09).

[0116] Production of the Compounds:

[0117] Ref. 2 to 8, Examples 1 to 6

[0118] The plastic molding materials described in the comparative examples and the inventive examples were produced by melt mixing of the individual components in a ZSK 26 MC twin-screw extruder from Coperion at a throughput of 25 kg/h and a housing temperature of 260° C. The melt was discharged as a strand through a 4 mm die, cooled in a water bath until pelletizable and pelletized.

[0119] Production of the Test Specimens:

[0120] Ref. 1:

[0121] Test specimens for testing notched impact strength were produced according to ISO 179-2/1 eA on an Arburg 420C injection molding machine at a melt temperature of about 240° C. and a mold temperature of about 80° C. Plates having dimensions of 60×60×2 mm.sup.3 for gloss assessment and for testing resistance to road salt and automatic carwashes were produced on the same injection molding machine at the same temperatures using a highly polished counter plate.

[0122] Ref. 2 to 8, Examples 1 to 6:

[0123] Test specimens for testing notched impact strength were produced according to ISO 179-2/1 eA on an Arburg 420C injection molding machine at a melt temperature of about 280° C. and a mold temperature of about 100° C. Plates having dimensions of 60×60×2 mm.sup.3 for gloss assessment and for testing resistance to road salt and automatic carwashes were produced on the same injection molding machine at a melt temperature of about 270° C. and a mold temperature of about 30° C. using a highly polished counter plate.

[0124] The results are shown summarized in table 1.

[0125] Evaluation of the Results:

[0126] Ref. 1: SAN (Luran® HH 120 SPF50) is a commercially available product for exterior automotive parts having a high gloss appearance with a piano lacquer look. The material has a very high gloss value; however, it is very brittle and therefore not well suited for components with integrated functionality, such as for example snap hooks, or for crash-relevant parts. It also has a very low gloss retention in the carwash test.

[0127] Ref. 2 to 4: Standard polyamides such as PA6, PA6,6 and PA6,6/6 have markedly higher toughnesses at acceptable gloss values and also a significantly improved resistance to automatic carwashes but road salt resistance is low for these materials.

[0128] Ref. 5: PA6,10 (Zytel® RX LC3060) ensures very good resistance to road salt. However, the use of pure PA6,10 results in lower initial gloss and reduced gloss retention compared to standard polyamides (Ref. 2 to 4).

[0129] Ref. 6: A mixture of 100 parts of PA6,10 with 25 parts of PA6,6 is resistant to road salt and has better resistance to automatic carwashes compared to pure PA6,10 but the initial gloss value is further reduced.

[0130] Surfaces with at least 88 gloss units according to DIN EN ISO 2813 (2015) are considered high-gloss.

[0131] Ref. 7 and 8: Mixtures of 100 parts of PA6,10 with 120 or more parts of PA6 and/or PA6,6/6 show a markedly reduced resistance to road salt.

[0132] Examples 1 to 6: Mixtures of 100 parts of PA6,10 with 5 to 90 parts of PA6 and/or PA6,6/6 show improved gloss and gloss retention in the automatic carwash test compared to pure PA6,10 at similar toughness and high road salt resistance (gray scale at least 4 according to test).

TABLE-US-00005 TABLE 1 Ref. 1 Ref. 2 Ref. 3 Ref. 4 Ref. 5 Ref. 6 Ref. 7 Ref. 8 Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 SAN 100 PA 66 99.2 25 PA 6 99.2 25 PA 6,6/6 99.2 120 160 5 10 25 45 90 PA 6,10 99.2 100 100 100 100 100 100 100 100 100 Carbon black 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Calcium stearate 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Notched impact 1.3 3.1 6.0 5.2 4.7 3.6 3.5 3.9 4.7 4.7 4.6 4.0 3.7 3.8 strength 23° C. (kJ/m.sup.2) Road salt re- no severe severe severe no no slight marked no no no no no minimal sistance test ac- dam- crack- crack- crack- dam- dam- graying gray- dam- dam- dam- dam- dam- graying cording to DBL age ing, ing, ing, age age ing age age age age age 5416, 7.3 graying gray- graying ing gray scale as- 5 1 1 1 5 5 3-4 3 5 5 5 5 4-5 4 sessment accord- ing to ISO 105 A02 after testing according to DBL 5416, 7.3 Gloss (%) at 20° 99.9 91.5 90.8 91.3 86.8 83.7 88.9 88.5 89.0 88.4 88.9 88.9 88.7 88.8 angle Gloss retention 14 37 42 42 25 36 36 38 35 27 32 33 33 34 (20°) after auto- matic carwash test (%)