LOW DENSITY POLYETHER BLOCK AMIDE AND HOLLOW GLASS REINFORCEMENT COMPOSITIONS AND USE OF SAME

Abstract

The present invention relates to a moulding composition comprising by weight: (A) 65% to 98%, in particular 65% to 95%, of at least one copolyamide with amide units (Ba1) and polyether units (Ba2), (B) 2% to 30%, in particular 5% to 30%, of hollow glass reinforcement, (C) 0 to 5%, preferably 0.1% to 2%, of at least one additive, the sum of the proportions of each constituent (A) + (B) + (C) of the composition being equal to 100%.

Claims

1. A molding composition, comprising by weight: (A) from 65% to 98%of at least one copolyamide with amide units (Ba1) and with polyether units (Ba2), (B) from 2% to 30%,of hollow glass reinforcement, (C) from 0% to 5% of at least one additive, the sum of the proportions of each constituent (A) + (B) + (C) of said composition being equal to 100%.

2. The composition as claimed in claim 1, wherein said amide unit (Ba1) corresponds to a repeating unit chosen from a unit obtained from at least one amino acid or a unit obtained from at least one lactam, or a unit X.Y obtained from the polycondensation of at least one diamine and at least one dicarboxylic acid.

3. The composition as claimed in claim 1, wherein the polyether units (Ba2) are chosen from polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene glycol (PO3G), polytetramethylene glycol (PTMG) and the mixtures or copolymers thereof.

4. The composition as claimed in claim 1, wherein the copolyamide with amide units (Ba1) and with polyether units (Ba2) has a density greater than or equal to 1, as determined in accordance with ISO 1183-3: 1999.

5. The composition as claimed in claim 1, the molding composition has a density of less than 1, as determined in accordance with ISO 1183-3: 1999.

6. The composition as claimed in claim 1, e the hollow glass reinforcement content is comprised from 5 to 25% by weight.

7. The composition as claimed in claim 1, the hollow glass reinforcement is hollow glass beads.

8. The composition as claimed in claim 7,wherein the hollow glass beads have a volume mean diameter d.sub.50 of 10 to 80 .Math.m, as measured using laser diffraction in accordance with ASTM standard B 822-17.

9. The composition as claimed in claim 7, the hollow glass beads have a real density from 0.10 to 0.65 g/cm.sup.3, measured in accordance ASTM D 2840-69 (1976) using a gas pycnometer and helium as the measuring gas.

10. The composition as claimed in claim 7, wherein the hollow glass beads have a compressive strength, as measured in accordance with ASTM D 3102-72 (1982) in glycerol, of at least 50 MPa .

11. The composition as claimed in claim 7, wherein the amide unit (Ba1) is chosen from polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 1010, polyamide 1012.

12. The composition as claimed in claim 1, wherein the amide unit (Ba1) is chosen from polyamide 11 and polyamide 12.

13. The composition as claimed in claim 1, wheŗein said at least one additive is chosen from fillers, dyes, stabilizers, plasticizers, surfactants, nucleating agents, pigments, whitening agents, antioxidants, lubricants, flame retardants, natural waxes, impact modifiers and mixtures thereof.

14. A method comprising the use of a composition as defined in claim 1, for the manufacture of an article.

15. The method as claimed in claim 14, wherein the article is manufactured by injection molding.

16. An article obtained by injection molding with a composition as defined in claim 1.

17. A method comprising the use of 2 to 30% by weight of hollow glass reinforcement with at least one polyether block amide (PEBA) said PEBA being present from 65 to 98% by weight and said additive being comprised from 0 to 5% by weight, to make up a composition as defined in claim 1, the density of which is less than that of said PEBA used alone with optionally at least one additive, and said density of said composition being less than 1.

Description

EXAMPLES

[0128] Preparation of the compositions of the invention and mechanical properties: [0129] The compositions of tables I and II were prepared by melt blending PEBA granules with the hollow glass beads and, optionally the additives. This mixture was made by compounding on a 26 mm diameter twin-screw co-rotating extruder with a flat temperature profile (T°) at 250° C. The screw speed is 250 rpm and the flow rate is 15 kg/h.

[0130] The introduction of the hollow glass beads is carried out with a side feeder.

[0131] The one or more PEBAs and the additives are added during the compounding process in the main hopper.

[0132] The compositions were then molded on an injection molding machine (Engel) at a setpoint temperature of 220° C. and a molding temperature of 50° C. in the shape of dumbbells (see tables 3 and 4) or bars in order to study the properties of the compositions according to the standards below.

[0133] The tensile modulus was measured at 23° C. according to ISO standard 527-1: 2012 on dumbbells of type 1A.

[0134] The machine used is of the I NSTRON 5966 type. The speed of the crosshead is 1 mm/min for the modulus measurement. The test conditions are 23° C. +/- 2° C., on dry samples.

[0135] The impact strength was determined according to ISO 179-1: 2010/1eU (Charpy impact) on non-notched bars of size 80 mm × 10 mm × 4 mm, at a temperature of 23° C. +/- 2° C. at a relative humidity of 50% +/- 10% or at -30° C. +/- 2° C. at a relative humidity of 50% +/- 10% on dry samples.

[0136] The density of the injected compositions was measured in accordance with ISO standard 1183-3:1999 at a temperature of 23° C. on bars of size 80 mm × 10 mm × 4 mm.

TABLE-US-00001 The contents are expressed as a % by weight CE 1 E1 E2 E3 E4 E5 E6 PEBA 11/PTMG 50% PTMG, d = 1.03 100 94.70 89.70 89.70 84.70 79.70 PEBA 12/PTMG 50% PTMG, d = 1.00 89.70 iM16k hollow glass beads from 3 M - 5.00 10.00 10.00 15.00 20.00 L20090 hollow glass beads from 3 M 10.00 additives - 0.3 0.3 0.3 0.3 0.3 0.3 density (g/cm3) 1.03 0.99 0.97 0.97 0.95 0.95 0.92 Tensile modulus (according to ISO527:2012) in MPa 83 100 115 118 117 140 183 Non-notched Charpy impact according to ISO 179-1:2010/1eU strength (kJ/m.sup.2) at 23° C. NB NB NB NB NB NB NB Non-notched Charpy impact according to ISO 179-1:2010/1eU at -30° C. (kJ/m.sup.2) NB NB NB NB NB NB NB Elongation measured according to ISO 527-1:2019 (%) >500 >500 >500 >500 >500 >200 >100 NB: No breakage

TABLE-US-00002 The contents are expressed as a % by weight CE2 E7 E8 E9 E10 PEBA 11/PTMG 4% PTMG, d = 1.03 100 94.7 89.7 84.7 79.7 iM16k hollow glass beads from 3 M - 5.00 10.00 15.00 20.00 additives 0.3 0.3 0.3 0.3 0.3 density (g/cm3) 1.03 0.99 0.98 0.96 0.94 Tensile modulus (according to ISO527:2012) in MPa 827 884 1033 1196 1303 Non-notched Charpy impact according to ISO 179-1:2010/1eU strength (kJ/m.sup.2) at 23° C. NB NB NB NB NB Non-notched Charpy impact according to ISO 179-1:2010/1eU at -30° C. (kJ/m.sup.2) NB NB NB NB NB Elongation measured according to ISO 527-1:2019 (%) >300 >50 >30 >30 >30 NB: No breakage

[0137] The addition of hollow glass beads to the PEBA makes it possible to significantly decrease the density of the compositions relative to PEBA alone and thus to obtain compositions that are lighter in weight than just PEBA alone, without losing rigidity and while having very good impact strength and good processability (see tables 3 and 4).

[0138] The dumbbells of type 1A were obtained by injection on an Engel-type injection molding machine:

TABLE-US-00003 Injection temperature (°C) from the nozzle to the hopper (setpoint value) Injection pressure (bar) measured Mold temperature (°C) (Setpoint value) Cycle time (s) Injectability and surface appearance (visual) CE1 215/220/220/205 1046 50 100 OK E1 1220 130 OK E2 1233 80 OK E3 1231 80 OK E4 1230 80 OK E5 1248 55 OK E6 1165 60 OK

TABLE-US-00004 Injection temperature (°C) from the nozzle to the hopper (setpoint value) Injection pressure (bar) measured Mold temperature (°C) (Setpoint value) Cycle time (s) Injectability and surface appearance (visual) CE2 215/220/220/205 1174 50 56 OK E7 1146 56 OK E8 1251 62 OK E9 1280 56 OK E10 1333 56 OK