LIGHTWEIGHT STYRENE POLYMER COMPOSITIONS

Abstract

A thermoplastic molding composition is provided for use in automotive applications comprising: A) 40 to 88% by weight of an ABS and/or ASA resin, B) 5 to 30% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) optionally 1 to 5% by weight of a compatibilizing agent, E) optionally 0 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

Claims

1-18. (canceled)

19. A thermoplastic molding composition comprising, as components A) to F), A) 40 to 88% by weight of ABS and/or ASA resin B) 5 to 30% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of chemical foaming agent, D) optionally 1 to 5% by weight of compatibilizing agent, E) optionally 0 to 20% by weight of impact modifier, and F) optionally 0.1 to 3% by weight of plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

20. Thermoplastic molding composition according to claim 19, comprising the components A) to F) in the following amounts: A) 40 to 88% by weight of an ABS and/or an ASA resin, B) 5 to 30% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) 5 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid component, wherein the sum of components A) to F) totals 100% by weight.

21. Thermoplastic molding composition according to claim 19, comprising the components A) to F) in the following amounts: A) 50 to 88% by weight of an ABS and/or an ASA resin, B) 5 to 30% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) 0.1 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid component, wherein the sum of components A) to F) totals 100% by weight.

22. Thermoplastic molding composition according to claim 19, comprising the components A) to F) in the following amounts: A) 50 to 75% by weight of a ABS and/or ASA resin, preferably ABS resin, B) 10 to 25% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) optionally 0 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

23. Thermoplastic molding composition according to claim 19, comprising the components A) to F) in the following amounts: A) 50 to 75% by weight of an ABS and/or ASA resin, preferably an ABS resin, B) 10 to 25% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) 0.1 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

24. Thermoplastic molding composition according to claim 19, comprising components A) to F), in the following amounts: A) 50 to 70% by weight of an ABS and/or ASA resin, preferably an ABS resin, B) 10 to 25% by weight of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) 5 to 20% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

25. Thermoplastic molding composition according to claim 19, comprising components A) to F), in the following amounts: A) 55 to 70% by weight of an ABS and/or ASA resin, preferably an ABS resin, B) 12 to 22% by weight of hollow glass microspheres, C) 0.5 to 2.0% by weight of a chemical foaming agent, D) 3 to 4% by weight of a compatibilizing agent, E) 5 to 17% by weight of an impact modifier, and F) optionally 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

26. Thermoplastic molding composition according to claim 19, comprising components A) to F), in the following amounts: A) 50 to 70% by weight of an ABS and/or ASA resin, preferably an ABS resin, B) 10 to 25%, preferably 12 to 22% by weight, of hollow glass microspheres, C) 0.1 to 2.5% by weight of a chemical foaming agent, D) 1 to 5% by weight of a compatibilizing agent, E) 5 to 20% by weight of an impact modifier, and F) 0.1 to 3% by weight of a plastic processing aid, wherein the sum of components A) to F) totals 100% by weight.

27. A thermoplastic molding composition as claimed in claim 19, wherein component A) is an ABS resin.

28. A thermoplastic molding composition as claimed in claim 27, wherein component A) is an ABS resin A) comprising an ABS graft copolymer A1) and a styrene-acrylonitrile (SAN) copolymer A2).

29. A thermoplastic molding composition as claimed in claim 19, wherein component A) is an ASA resin.

30. A thermoplastic molding composition as claimed in claim 19, wherein the hollow glass microspheres B) are mono-modal having a particle size in the range from 5 to 50 m, preferably 15 to 25 m.

31. A thermoplastic molding composition as claimed in claim 19 wherein the chemical foaming agent C) is one or more components selected from the group consisting of: Azodicarbonamide (ADC), 4,4-Oxybis(benzenesulfonyl-hydrazide) (OBSH), P-Toluenesulfonylhydrazide (TSH), P-toluenesulfonylsemi-carbazide (TSS), Dinitrosopentamethlenetetramine, Polyphenyl sulfoxide (PPSO) and 5-phenyltetrazole, Sodium carbonate, Sodium bicarbonate, Magnesium carbonate, Stearic acid, Sodium stearate, Potassium stearate, Magnesium stearate, Zinc carbonate, Citric acid derivatives and other organic acids and their salts.

32. A thermoplastic molding composition as claimed in claim 19 wherein the compatibilizing agent D) is selected from styrene-maleic anhydride copolymers, styrene-acrylonitrile-maleic anhydride copolymers and N-Phenyl maleic imide-maleic anhydride copolymers.

33. A thermoplastic molding composition as claimed in claim 19 wherein the impact modifier E) is a block copolymer comprising monomer units of a vinylaromatic monomer and a diene.

34. A process for the preparation of the thermoplastic molding composition according to claim 19 comprising the following steps: i) Mixing and melting of components A) and optional components D), E), F), K) and L), if present, in the feeding section of a twin-screw extruder having high channel depth conveying elements; ii) Addition of component B) by a side-feed in a zone of the extruder after the kneading section; iii) Mixing and injection-molding of the obtained extruded polymer blend with a chemical foaming agent C).

35. A shaped article comprising the thermoplastic molding composition according to claim 19.

36. A method of using the shaped article according to claim 35 for automotive applications.

Description

EXAMPLES

Materials:

[0156] ABS: Terluran HI-10 (high impact, medium flow, injection molding and extrusion grade ABS of Styrolution, Frankfurt).

[0157] Hollow glass microspheres supplied by the U.S. company 3M (soda lime borosilicate glass beads, density 0. 46 g/cc, particles 16 m diameter, Isotactic pressure resistance 113 Mpa).

[0158] Impact modifier: a SBC Styroflex 2G66 (S-TPE for extrusion, Styrolution, Frankfurt).

[0159] Compatibilizing agent: a Styrene-Acrylonitrile grafted maleic anhydride (SAN-g-MAH) copolymer made according to US Patent 8,030,393 B2 (Styrolution VT2421).

[0160] Chemical foaming agent (CFA): an azodicarbonamide supplied as Hydrocerol CF-40-T by Clariant, Frankfurt.

TABLE-US-00001 TABLE 1 Thermoplastic Molding Composition (in % by weight) Designation Examp. 1 Example 2 Example 3 ABS resin 87 69 58 Glassbeads (16 m) 5 14 20 Compatibilizer 2.5 4 4 Impact modifier 5 12 16 CFA 0.5 1 2 Total 100 100 100

Example 1

[0161] Step 1, a mixture of 87% by weight of ABS resin, 2.5% Compatibilizer; 5% impact modifier is prepared and pre-mixed to obtain a uniformly mixed material.

[0162] Step 2, the mixture is added into a twin-screw extruder hopper (in feeding zone 1 of the extruder). The compounding was performed on an twin screw extruder machine (manufacturer: Berstorff ZE25 L/D=33D, OD/ID: 1.75) at a temperature of 240 C. and 250 r.p.m. Hollow glass beads are added at 5% by weight using a side feeder (placed after the kneading zone of the extruder) as to introduce the glass beads to the polymer melt to avoid breakage. The polymer composition containing additionally the glass beads was extruded via a die plate and the water chilled polymer strands were granulated.

[0163] Step 3, the granulated polymer was pre-mixed with 0.5% by weight of a chemical foaming agent and then the pre-mixed composition was injection molded with a common injection molding machine (LG ID 75EN) at 240 C., 75MT clamp force, 60% injection speed, 55 C. mold temperature, to a 3.2 mm thick specimen used for stress/strain test according to the norm ASTM D638 and to 3.2 mm thickness specimen according to the norm ASTM D256.

Example 2

[0164] Step 1, a mixture of 69% by weight of ABS resin, 4% Compatibilizer; 12% impact modifier is prepared and pre-mixed to obtain a uniformly mixed material.

[0165] Step 2, the mixture is added into a twin-screw extruder hopper (in feeding zone 1 of the extruder). The compounding was performed on an twin screw extruder machine (manufacturer: Berstorff ZE25 L/D=33D, OD/ID:1.75) at a temperature of 240 C. and 250 r.p.m. Hollow glass beads are added at 14% by weight using a side feeder (placed after the kneading zone of the extruder) as to introduce the glass beads to the polymer melt to avoid breakage. The polymer composition containing additionally the glass beads was extruded via a die plate and the water chilled polymer strands were granulated.

[0166] Step 3, the granulated polymer was pre-mixed with at 1 wt.-% of a chemical foaming agent and then the pre-mixed composition was injection molded with a common injection molding machine (LG ID 75EN) at 240 C., 75MT clamp force, 60% injection speed, 55 C. mold temperature, to a 3.2 mm thick specimen used for stress/strain test according to the norm ASTM D638 and to 3.2 mm thickness specimen according to the norm ASTM D256.

Example 3

[0167] Step 1, a mixture of 58% by weight of ABS resin, 4% compatibilizer; 16% impact modifier is prepared and pre-mixed to obtain a uniformly mixed material.

[0168] Step 2, the mixture is added into a twin-screw extruder hopper (in feeding zone 1 of the extruder). The compounding was performed on an twin screw extruder machine (manufacturer: Berstorff ZE25 L/D=33D, OD/ID: 1.75) at a temperature of 240 C. and 250 r.p.m. Hollow glass beads are added at 20% by weight using a side feeder (placed after the kneading zone of the extruder) as to introduce the glass beads to the polymer melt to avoid breakage. The polymer composition containing additionally the glass beads was extruded via a die plate and the water chilled polymer strands were granulated.

[0169] Step 3 The granulated polymer was pre-mixed with a chemical foaming agent at 2% and then the pre-mixed composition was injection molded with a common injection molding machine (LG ID 75EN) at 240 C., 75MT clamp force, 60% injection speed, 55 C. mold temperature, to a 3.2 mm thick specimen used for stress/strain test according to the norm ASTM D638 and to 3.2 mm thickness specimen according to the norm ASTM D256 (norm used on date of filing).

Performance Testing and Evaluation:

[0170] Results of testing performed on ABS pellets presented in examples 1 to 3 are listed in the table below:

TABLE-US-00002 Tests Units Example 1 Examp. 2 Example 3 CharpyNotched [23 C.] kJ/m.sup.2 22 14 11 ISO 179/1eA Melt Volume Rate 220 C./ cm.sup.3/10 15 12 10 10 kg ISO 1133* min Tensile Stress at Yield ISO Mpa 43 42 42 527-2/1A/1 Tensile Strain at Yield ISO % 4.2 4 4 527-2/1A/50 Tensile Strain at Break ISO % 11 9 8 527-2/1A/50 Tensile Modulus ISO Mpa 2400 2710 3080 527-2/1A/50 Flexural Modulus ISO178 Mpa 2300 2630 2800 Flexural Strength ISO179 Mpa 68 67 66 Vicat Softening Temperature C. 95 96 98 ISO 306/B50 (50N at 50 C./hr) [40 hr, ASTM] Heat Deflection Temperature C. 79 82 84 at 1.82 Mpa [264 psi] Unannealled ISO 75-2/Af Weight Reduction % 7 16 23 Ash Content ASTM D5630 % 5.1 13.9 20 *Without CFA

[0171] As the results show, by the combination of applying hollow glass beads and a chemical foaming agent, it was possible to achieve a high weight reduction and the best retention of advanced properties, making this concept a very viable option for many industries seeking weight reduction without sacrificing much of mechanical properties.

[0172] In general, Charpy and MVR properties showed some deterioration but remained within acceptable ranges. Tensile properties remained similar while Tensile and Flexural modulus showed a significant improvement. Heat performance properties improved as well. PATENT