Polymer compositions of improved scratch resistance, improved mechanical stability and improved haze
11401399 · 2022-08-02
Assignee
Inventors
Cpc classification
C08K5/0083
CHEMISTRY; METALLURGY
International classification
C08K3/00
CHEMISTRY; METALLURGY
C08F210/16
CHEMISTRY; METALLURGY
Abstract
The present invention provides a composition comprising (i) a polymer, (ii) an organic compound A carrying at least two amide functionalities, and (iii) 12 to 1'000 parts per million (ppm) of a compound B selected from the group consisting of an organic compound C carrying at least two amide functionalities, sugar alcohol acetals and derivatives thereof, metal salts of organic acids and precursor-systems thereof, metal salts of organic phosphoric acids and precursor-systems thereof and metal salts of polyols and precursor-systems thereof, and mixtures thereof, based on the weight of the polymer, as well as shaped articles obtainable from this composition.
Claims
1. A composition, comprising: (i) at least one polymer selected from the group consisting of polypropylene homopolymers (ii) 150 to 300 parts per million (ppm) of an organic compound A which is 1,3,5-tris-[2,2-dimethylpropionylamino]benzene, based on the weight of the polymer, and (iii) 150 to 300 parts per million (ppm) of at least one compound B selected from the group consisting of 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol, a metal salt of 2,2′-methylene bis(4,6-di-tert-butylphenyl)phosphate, aluminium-hydroxy-bis[2,2′-methylene-bis(4,6-di-tert-butylphenyl)phosphate, and a zinc glycerolate, based on the weight of the polymer.
2. The composition of claim 1, wherein the compound B is 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol.
3. The composition of claim 1, wherein the compound B is lithium 2,2′-methylene bis(4,6-di-tert-butylphenyl)phosphate.
4. The composition of claim 1, wherein the compound B is zinc glycerolate.
5. The composition of claim 1, having a haze of from 42.90% to 40.46%.
6. The composition of claim 1, wherein the compound B is aluminium-hydroxy-bis [2,2′-methylene-bis(4,6-di-tert-butylphenyl) phosphate.
7. A composition, comprising: (i) at least one polymer selected from the group consisting of polypropylene random copolymers containing 90 to 99.9 mol % propylene and 0.01 to 10 mol % ethylene as a comonomer, wherein the total amount of propylene and ethylene in the polymer is 100 wt %, (ii) 150 to 300 parts per million (ppm) of an organic compound A which is 1,3,5-tris-[2,2-dimethylpropionylamino]benzene, based on the weight of the polymer, and (iii) 150 to 300 parts per million (ppm) of at least one compound B selected from the group consisting of 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol, a metal salt of 2,2′-methylene bis(4,6-di-tert-butylphenyl)phosphate, aluminium-hydroxy-bis[2,2′-methylene-bis(4,6-di-tert-butylphenyl)phosphate, and a zinc glycerolate, based on the weight of the polymer.
8. The composition of claim 7, wherein the compound B is 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol.
9. The composition of claim 7, wherein the compound B is lithium 2,2′-methylene bis(4,6-di-tert-butylphenyl)phosphate.
10. The composition of claim 7, wherein the compound B is zinc glycerolate.
11. The composition of claim 7, wherein the compound B is aluminium-hydroxy-bis[2,2′-methylene-bis(4,6-di-tert-butylphenyl)phosphate.
Description
EXAMPLES
Examples 1 to 11, and Comparative Examples 1 to 17
(1) The nucleating agents and mixtures of nucleating agents as indicated in table 1 are mixed with dry powder form polypropylene (PP), random copolymer comprising 4 mole % ethylene (RD 204 CF from Borealis AG, Vienna, Austria) in a high speed mixer (Mixaco Lab CM 12) and are compounded at 230° C. to pellets in a twin-extruder (Berstorff ZE 25×33 D). Polypropylene (PP) random copolymer without nucleating agents is treated analogously (comparative example 1).
(2) TABLE-US-00001 TABLE 1 Example No. Nucleating agent [ppm].sup.a Comp. ex. 1 — — Comp. ex. 2 Millad ® 3988.sup.b 1800 Comp. ex. 3 Millad ® 3988.sup.b 450 Comp. ex. 4 Millad ® 3988.sup.b 300 Comp. ex. 5 Millad ® 3988.sup.b 150 Comp. ex. 6 Ciba ® Irgastab ® NA 11.sup.c 450 Comp. ex. 7 Ciba ® Irgastab ® NA 11.sup.c 300 Comp. ex. 8 Ciba ® Irgastab ® NA 11.sup.c 150 Comp. ex. 9 Hyperform ® HPN-68L.sup.d 230 Comp. ex. 10 Hyperform ® HPN-68L.sup.d 150 Comp. ex. 11 Ciba ® Irgastab ® NA 287.sup.e 230 Comp. ex. 12 Ciba ® Irgastab ® NA 287.sup.e 150 Comp. ex. 13 Ciba ® Irgastab ® NA 04.sup.f 850 Comp. ex. 14 Ciba ® Irgaclear ® XT 386.sup.g 450 Comp. ex. 15 Ciba ® Irgaclear ® XT 386.sup.g 300 Comp. ex. 16 Ciba ® Irgaclear ® XT 386.sup.g 230 Comp. ex. 17 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 1 Millad ® 3988.sup.b 300 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 2 Millad ® 3988.sup.b 150 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 3 Ciba ® Irgastab ® NA 11.sup.c 300 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 4 Ciba ® Irgastab ® NA 11.sup.c 150 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 6 Hyperform ® HPN-68L.sup.d 75 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 7 Hyperform ® HPN-68L.sup.d 75 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 8 Ciba ® Irgastab ® NA 287.sup.e 75 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 9 Ciba ® Irgastab ® NA 287.sup.e 75 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 11 Ciba ® Irgastab ® NA 04.sup.f 850 Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.aby weight based on the weight of the polypropylene (PP) random copolymer. .sup.bMillad ® 3988 (Milliken) is 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol. .sup.cCiba ® Irgastab ® NA 11 is sodium 2,2′-methylene bis(4,6-di-tert-butylphenyl)phosphate of formula
(3) Testing of Flexural Modulus
(4) The pellets of examples 1 to 4, 6 to 9 and 11, and comparative examples 1 to 4, 6, 7 and 9 to 13, 16 and 17 are injection molded at 200° C. to obtain 4 mm thick bars of 10 mm width and 80 mm length.
(5) The bars are subjected to a “3-point bending test” according to ISO 178. The flexural modulus or elastic modulus (E.sub.f) is determined from the linear regime of the stress-strain curves. The flexural or elastic modulus is a measure of the stiffness of the polymer material. The results are outlined in table 2.
(6) TABLE-US-00002 TABLE 2 Calculated flexural flexural Exam- modulus modulus.sup.h ple No. Nucleating agent [ppm].sup.a [MPa] [MPa] Comp. — — 1039 — ex. 1 Comp. Millad ® 3988.sup.b 1800 1239 — ex. 2 Comp. Millad ® 3988.sup.b 450 1060 ex. 3 Comp. Millad ® 3988.sup.b 300 1075 — ex. 4 Comp. Ciba ® Irgastab ® NA 11.sup.c 450 1415 — ex. 6 Comp. Ciba ® Irgastab ® NA 11.sup.c 300 1411 — ex. 7 Comp. Hyperform ® HPN-68L.sup.d 230 1249 — ex. 9 Comp. Hyperform ® HPN-68L.sup.d 150 1250 — ex. 10 Comp. Ciba ® Irgastab ® NA 287.sup.e 230 1170 — ex. 11 Comp. Ciba ® Irgastab ® NA 287.sup.e 150 1166 — ex. 12 Comp. Ciba ® Irgastab ® NA 04.sup.f 850 1275 — ex. 13 Comp. Ciba ® Irgaclear ® XT 386.sup.g 230 1339 — ex. 16 Comp. Ciba ® Irgaclear ® XT 386.sup.g 150 1233 — ex. 17 Ex. 1 Millad ® 3988.sup.b 300 1331 — Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 2 Millad ® 3988.sup.b 150 1275 — Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 3 Ciba ® Irgastab ® NA 11.sup.c 300 1444 — Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 4 Ciba ® Irgastab ® NA 11.sup.c 150 1434 — Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 6 Hyperform ® HPN-68L.sup.d 75 1350 1309.3 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 7 Hyperform ® HPN-68L.sup.d 75 1256 1241.5 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 8 Ciba ® Irgastab ® NA 287.sup.e 75 1240 1199.5 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 9 Ciba ® Irgastab ® NA 287.sup.e 75 1366 1283.2 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 11 Ciba ® Irgastab ® NA 04.sup.f 850 1274 — Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.a-gsee table 1. .sup.hthe calculated flexural (elastic) modulus of n ppm of a mixture of a % A and b % B = a % × “flexural (elastic) modulus of n ppm A” + b % × “flexural (elastic) modulus of n ppm B”. For example the calculated flexural (elastic) modulus of 230 ppm of a mixture of 33% Hyperform ® HPN-68L and 67% Ciba ® Irgaclear ® XT 386 (example 6) = 33% × “flexural (elastic) modulus of 230 ppm Hyperform ® HPN-68L” + 67% × “flexural (elastic) modulus of 230 ppm Ciba ® Irgaclear ® XT 386” = 33% × 1249 + 67% × 1339 = 1309.3.
(7) As can be seen from table 2 polypropylene copolymer compositions comprising 75 ppm Hyperform® HPN-68L and 155 ppm Ciba® Irgaclear® XT 386 (example 6) show an improved (higher) flexural (elastic) modulus, namely 1350 MPa, compared with the polypropylene copolymer compositions comprising 230 ppm Hyperform® HPN-68L (flexural modulus=1249 MPa, comparative example 9) or 230 ppm Ciba® Irgaclear® XT 386 (flexural modulus=1339 MPa, comparative example 16). The effect is not of additive nature, but synergistic as can be seen when comparing the measured flexural (elastic) modulus (1350 MPa) with the calculated flexural (elastic) modulus (1309.3 MPa).
(8) Table 2 shows the same effect regarding the flexural (elastic) modulus of the polypropylene copolymer compositions comprising 75 ppm Hyperform® HPN-68L and 75 ppm Ciba® Irgaclear® XT 386 (example 7), 75 ppm Ciba® Irgastab® NA 287 and 75 ppm Ciba® Irgaclear® XT 386 (example 8), respectively, 75 ppm Ciba® Irgastab® NA 287 and 155 ppm Ciba® Irgaclear® XT 386 (example 9).
(9) Testing of Haze
(10) The pellets of examples 1 to 4, 6 to 9, and 11, and comparative examples 1 to 7 and 9 to 17 are molded at 230° C. to plaques with a thickness of 1 mm using a standard injection molding machine (Engel HL 60).
(11) The hazes the plaques are analysed using a Haze-gard plus instrument (BYK Gardner Gmbh Germany) in accordance with ASTM standard D1003. In this test, haze is commonly defined as that portion of visible light that is scattered at wider angles (2.5°<θ<90°) and is a measure for the turbidity of a sample.
(12) The results are outlined in table 3.
(13) TABLE-US-00003 TABLE 3 Haze Calculated Example No. Nucleating agent [ppm].sup.a [%] Haze.sup.i [%] Comp. ex. 1 — — 40.32 — Comp. ex. 2 Millad ® 3988.sup.b 1800 12.16 — Comp. ex. 3 Millad ® 3988.sup.b 450 38.36 — Comp. ex. 4 Millad ® 3988.sup.b 300 39.50 — Comp. ex. 5 Millad ® 3988.sup.b 150 39.06 — Comp. ex. 6 Ciba ® Irgastab ® NA 11.sup.c 450 23.28 — Comp. ex. 7 Ciba ® Irgastab ® NA 11.sup.c 300 25.74 — Comp. ex. 9 Hyperform ® HPN-68L.sup.d 230 47.90 — Comp. Hyperform ® HPN-68L.sup.d 150 52.90 — ex. 10 Comp. Ciba ® Irgastab ® NA 287.sup.e 230 52.16 — ex. 11 Comp. Ciba ® Irgastab ® NA 287.sup.e 150 53.88 — ex. 12 Comp. Ciba ® Irgastab ® NA 04.sup.f 850 39.38 — ex. 13 Comp. Ciba ® Irgaclear ® XT 386.sup.g 450 12.66 — ex. 14 Comp. Ciba ® Irgaclear ® XT 386.sup.g 300 13.28 — ex. 15 Comp. Ciba ® Irgaclear ® XT 386.sup.g 230 14.90 — ex. 16 Comp. Ciba ® Irgaclear ® XT 386.sup.g 150 14.50 — ex. 17 Ex. 1 Millad ® 3988.sup.b 300 11.06 29.90 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 2 Millad ® 3988.sup.b 150 12.44 26.39 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 3 Ciba ® Irgastab ® NA 11.sup.c 300 18.72 19.78 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 4 Ciba ® Irgastab ® NA 11.sup.c 150 18.64 19.51 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 6 Hyperform ® HPN-68L.sup.d 75 15.30 25.80 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 7 Hyperform ® HPN-68L.sup.d 75 33.00 33.70 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 8 Ciba ® Irgastab ® NA 287.sup.e 75 27.48 34.19 Ciba ® Irgaclear ® XT 386.sup.g 75 Ex. 9 Ciba ® Irgastab ® NA 287.sup.e 75 16.18 27.2 Ciba ® Irgaclear ® XT 386.sup.g 155 Ex. 11 Ciba ® Irgastab ® NA 04.sup.f 850 30.42 — Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.a-gsee table 1. .sup.ithe calculated Haze of n ppm of a mixture of a % A and b % B = a % × “Haze of n ppm A” + b % × “Haze of n ppm B”.
(14) For example the calculated Haze of 230 ppm of a mixture of 33% Hyperform® HPN-68L and 67% Ciba® Irgaclear® XT 386 (example 6)=33%דHaze of 230 ppm Hyperform® HPN-68L”+67%דHaze of 230 ppm Ciba® Irgaclear® XT 386”=33%×47.90+67%×14.90=25.8.
(15) As can be seen from table 3 polypropylene copolymer compositions comprising 300 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 1) show an improved (lower) haze, namely 11.06, compared with the polypropylene copolymer compositions comprising 450 ppm Millad® 3988 (haze=38.36, comparative example 3) or 450 ppm Ciba® Irgaclear® XT 386 (haze=12.66, comparative example 14). The effect is not of additive nature, but synergistic as can be seen when comparing the measured haze (11.06) with the calculated haze (29.90).
(16) Table 3 shows the same effect regarding haze of the polypropylene copolymer compositions comprising 150 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 2), 300 ppm Ciba® Irgastab® NA 11 and 150 ppm Ciba® Irgaclear® XT 386 (example 3), 150 ppm Ciba® Irgastab® NA 11 and 150 ppm Ciba® Irgaclear® XT 386 (example 4), 75 ppm Hyperform® HPN-68L and 155 ppm Ciba® Irgaclear® XT 386 (example 6), 75 ppm Hyperform® HPN-68L and 75 ppm Ciba® Irgaclear® XT 386 (example 7), 75 ppm Ciba® Irgastab® NA 287 and 75 ppm Ciba® Irgaclear® XT 386 (example 8), respectively, 75 ppm Ciba® Irgastab® NA 287 and 155 ppm Ciba® Irgaclear® XT 386 (example 9).
(17) Measurement of Scratch Resistance
(18) The pellets of examples 1, 2, 4, 5, 10 and 11, and comparative examples 1, 2, 4, 5, 8, 10, 12, 13 and 17 are molded at 230° C. to plaques with a thickness of 1 mm using a standard injection molding machine (Engel HL 60). The scratch resistance of the plaques is analysed with an Erichson Sratch Tester by moving a sharp tip of 1 mm radius over the plaques at a velocity of 1000 mm/min and a normal force of 10 N. Evaluation of the scratch resistance is assessed by visual inspection as the transparent or translucent nature of the samples prevented changes in L* to be determined. The results are outlined in table 4. The transparency is also analysed by visual inspection. The results are also outlined in table 4.
(19) TABLE-US-00004 TABLE 4 Example Scratch Trans- No. Nucleating agent [ppm].sup.a resistance parency Comp. — — low low ex. 1 Comp. Millad ® 3988.sup.b 1800 low high ex. 2 Comp. Millad ® 3988.sup.b 300 medium low ex. 4 Comp. Millad ® 3988.sup.b 150 medium low ex. 5 Comp. Ciba ® Irgastab ® NA 11.sup.c 150 medium low ex. 8 Comp. Hyperform ® HPN-68L.sup.d 150 medium low ex. 10 Comp. Ciba ® Irgastab ® NA 287.sup.e 150 medium low ex. 12 Comp. Ciba ® Irgastab ® NA 04.sup.f 850 medium low ex. 13 Comp. Ciba ® Irgaclear ® XT 386.sup.g 150 medium high ex. 17 Ex. 1 Millad ® 3988.sup.b 300 high high Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 2 Millad ® 3988.sup.b 150 high high Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 4 Ciba ® Irgastab ® NA 11.sup.c 150 high medium Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 5 Hyperform ® HPN-68L.sup.d 150 high medium Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 10 Ciba ® Irgastab ® NA 287.sup.e 150 high medium Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 11 Ciba ® Irgastab ® NA 04.sup.f 850 high medium Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.a-gsee table 1.
(20) As can be seen from table 4, polypropylene copolymer compositions comprising 300 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 1),150 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 2), 150 ppm Ciba® Irgastab® NA 11 and 150 ppm Ciba® Irgaclear® XT 386 (example 4), 150 ppm Hyperform® HPN-68L and 150 ppm Ciba® Irgaclear® XT 386 (example 5), 150ppm Ciba® Irgastab® NA 287 and 150 ppm Ciba® Irgaclear® XT 386 (example 10), respectively, 850 ppm Ciba® Irgastab® NA 04and 150 ppm Ciba® Irgaclear® XT 386 (example 11) all show a high scratch resistance. The polypropylene copolymer compositions comprising 300 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 1), respectively, 150 ppm Millad® 3988 and 150 ppm Ciba® Irgaclear® XT 386 (example 2) also show a high transparency.
Examples 12 to 14, and Comparative Examples 18 to 22
(21) The nucleating agents and mixtures of nucleating agents as indicated in table 5 are mixed with dry powder form polypropylene (PP) random copolymer comprising 4 mole % ethylene (RD 204 MFI 8 from Borealis AG, Vienna, Austria) in a high speed mixer (Mixaco Lab CM 12) and are compounded at 230° C. to pellets in a twin-extruder (Berstorff ZE 25×46 D).
(22) TABLE-US-00005 TABLE 5 Example No. Nucleating agent [ppm].sup.a Comp. ex. 18 ADK Stab NA 71.sup.j 450 Comp. ex. 19 ADK Stab NA 71.sup.j 300 Comp. ex. 20 ADK Stab NA 21.sup.k 450 Comp. ex. 21 Ciba ® Irgaclear ® XT 386.sup.g 450 Comp. ex. 22 Ciba ® Irgaclear ® XT 386.sup.g 300 Ex. 12 ADK Stab NA 71.sup.j 150 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 13 ADK Stab NA 71.sup.j 300 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 14 ADK Stab NA 21.sup.k 300 Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.aby weight based on the weight of the polypropylene (PP) random copolymer. .sup.gCiba ® Irgaclear ® XT 386 is 1,3,5-tris[2,2-dimethylpropionylamino]benzene. .sup.jADK Stab NA 71 (Adeka) is lithium 2,2′-methylene-bis (4,6-di-tert-butylphenyl) phosphate of formula
(23) Measurement of Flexural Modulus
(24) The pellets of examples 12 to 13, and comparative examples 18 to 22 are injection molded at 200° C. to obtain 4 mm thick bars of 40 mm width and 80 mm length.
(25) The bars are subjected to a “3-point bending test” according to ISO 178. The flexural modulus or elastic modulus (E.sub.f) is determined from the linear regime of the stress-strain curves. The flexural or elastic modulus is a measure of the stiffness of the polymer material. The results are outlined in table 6.
(26) TABLE-US-00006 TABLE 6 Calculated flexural flexural modulus modulus.sup.h Example No. Nucleating agent [ppm].sup.a [MPa] [MPa] Comp. ex. 18 ADK Stab NA 71.sup.j 450 1113 — Comp. ex. 19 ADK Stab NA 71.sup.j 300 1110 — Comp. ex. 20 ADK Stab NA 21.sup.k 450 1083 Comp. ex. 21 Ciba ® Irgaclear ® 450 1147 — XT 386.sup.g Comp. ex. 22 Ciba ® Irgaclear ® 300 1165 — XT 386.sup.g Ex. 12 ADK Stab NA 71.sup.j 150 1177 1137.5 Ciba ® Irgaclear ® 150 XT 386.sup.g Ex. 13 ADK Stab NA 71.sup.j 300 1144 1124.2 Ciba ® Irgaclear ® 150 XT 386.sup.g Ex. 14 ADK Stab NA 21.sup.k 300 1172 1104.1 Ciba ® Irgaclear ® 150 XT 386.sup.g .sup.a, g, j and ksee table 5. .sup.hthe calculated flexural (elastic) modulus of n ppm of a mixture of a % A and b % B = a % × “flexural (elastic) modulus of n ppm A” + b % × “flexural (elastic) modulus of n ppm B”.
(27) For example the calculated flexural (elastic) modulus of 300 ppm of a mixture of 50% ADK Stab NA 71.sup.j and 50% Ciba® Irgaclear® XT 386 (example 12)=50%דflexural (elastic) modulus of 300 ppm ADK Stab NA 71.sup.j”+50%דflexural (elastic) modulus of 300 ppm Ciba® Irgaclear® XT 386”=50%×1110+50%×1165=1137.5.
(28) As can be seen from table 6 polypropylene copolymer compositions comprising 150 ppm ADK Stab NA 71 and 150 ppm Ciba® Irgaclear® XT 386 (example 12) show an improved (higher) flexural (elastic) modulus, namely 1177 MPa, compared with the polypropylene copolymer compositions comprising 300 ppm ADK Stab NA 71 (flexural modulus=1110 MPa, comparative example 19) or 300 ppm Ciba® Irgaclear® XT 386 (flexural modulus=1165 MPa, comparative example 22). The effect is not of additive nature, but synergistic as can be seen when comparing the measured flexural (elastic) modulus (1177 MPa) with the calculated flexural (elastic) modulus (1137.5 MPa).
(29) Table 6 shows the same effect regarding the flexural (elastic) modulus of the polypropylene copolymer compositions comprising 300 ppm ADK Stab NA 71 and 150 ppm Ciba® Irgaclear® XT 386 (example 13), respectively, 300 ppm ADK Stab NA 21 and 150 ppm Ciba® Irgaclear® XT 386 (example 14).
(30) Measurement of Haze
(31) The pellets of examples 12 to 13, and comparative examples 18 to 22 are molded at 200° C. to plaques with a thickness of 2 mm using a standard injection molding machine (Arburg 320S).
(32) The hazes the plaques are analysed using a Haze-gard plus instrument (BYK Gardner Gmbh Germany) in accordance with ASTM standard D1003. In this test, haze is commonly defined as that portion of visible light that is scattered at wider angles (2.5°<θ<90°) and is a measure for the turbidity of a sample.
(33) The results are outlined in table 7.
(34) TABLE-US-00007 TABLE 7 Haze Calculated Example No. Nucleating agent [ppm].sup.a [%] Haze.sup.i Comp. ADK Stab NA 71.sup.j 450 76.46 ex. 18 Comp. ADK Stab NA 71.sup.j 300 78.60 ex. 19 Comp. ADK Stab NA 21.sup.k 450 70.04 ex. 20 Comp. Ciba ® Irgaclear ® XT 386.sup.g 450 76.84 ex. 21 Comp. Ciba ® Irgaclear ® XT 386.sup.g 300 59.98 ex. 22 Ex. 12 ADK Stab NA 71.sup.j 150 41.00 69.29 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 13 ADK Stab NA 71.sup.j 300 42.90 76.58 Ciba ® Irgaclear ® XT 386.sup.g 150 Ex. 14 ADK Stab NA 21.sup.k 300 40.46 72.28 Ciba ® Irgaclear ® XT 386.sup.g 150 .sup.a,g,j and ksee table 5. .sup.ithe calculated Haze of n ppm of a mixture of a % A and b % B = a % × “Haze of n ppm A” + b % × “Haze of n ppm B”.
(35) For example the calculated Haze of 300 ppm of a mixture of 50% ADK Stab NA 71 and 50% Ciba® Irgaclear® XT 386 (example 12)=50%דHaze of 300 ADK Stab NA 71”+50%דHaze of 300 ppm Ciba® Irgaclear® XT 386”=50%×78.60 +50%×59.98=69.29
(36) As can be seen from table 7 polypropylene copolymer compositions comprising 150 ppm ADK Stab NA 71 and 150 ppm Ciba® Irgaclear® XT 386 (example 12) show an improved (lower) haze, namely 41.00, compared with the polypropylene copolymer compositions comprising 300 ppm ADK Stab NA 71 (haze=78.60, comparative example 19) or 300 ppm Ciba® Irgaclear® XT 386 (haze=59.98, comparative example 22). The effect is not of additive nature, but synergistic as can be seen when comparing the measured haze (41.00) with the calculated haze (69.29).
(37) Table 7 shows the same effect regarding haze of the polypropylene copolymer compositions comprising 300 ppm ADK Stab NA 71 and 150 ppm Ciba® Irgaclear® XT 386 (example 13), respectively, 300 ppm ADK Stab NA 21 and 150 ppm Ciba® Irgaclear® XT 386 (example 14)
Examples 15 to 17, and Comparative Examples 23 to 27
(38) The nucleating agents and mixtures of nucleating agents as indicated in table 8 are mixed with dry powder form polypropylene (PP) homopolymer (Moplen HP 500N, MFI 12) in a high speed mixer (Mixaco Lab CM 12) and are compounded at 230° C. to pellets in a twin-extruder (Berstorff ZE 25×46 D).
(39) TABLE-US-00008 TABLE 8 Example No. Nucleating agent [ppm].sup.a Comp. ex. 23 ADK Stab NA 71.sup.j 480 Comp. ex. 24 ADK Stab NA 71.sup.j 330 Comp. ex. 25 ADK Stab NA 21.sup.k 480 Comp. ex. 26 Ciba ® Irgaclear ® XT 386.sup.g 480 Comp. ex. 27 Ciba ® Irgaclear ® XT 386.sup.g 330 Ex. 15 ADK Stab NA 71.sup.j 150 Ciba ® Irgaclear ® XT 386.sup.g 180 Ex. 16 ADK Stab NA 71.sup.j 300 Ciba ® Irgaclear ® XT 386.sup.g 180 Ex. 17 ADK Stab NA 21.sup.k 300 Ciba ® Irgaclear ® XT 386.sup.g 180 .sup.aby weight based on the weight of the polypropylene (PP) homopolymer. .sup.g,,j and ksee table 5.
(40) Measurement of Flexural Modulus
(41) The pellets of examples 15 to 17, and comparative examples 23 to 27 are injection molded at 200° C. (Arburg 320S) to obtain 4 mm thick bars of 40 mm width and 80 mm length.
(42) The bars are subjected to a “3-point bending test” according to ISO 178. The flexural modulus or elastic modulus (E.sub.f) is determined from the linear regime of the stress-strain curves. The flexural or elastic modulus is a measure of the stiffness of the polymer material. The results are outlined in table 9.
(43) TABLE-US-00009 TABLE 9 Calculated flexural flexural modulus modulus.sup.h Example No. Nucleating agent [ppm].sup.a [MPa] [MPa] Comp. ex. 23 ADK Stab NA 71.sup.j 480 1736 Comp. ex. 24 ADK Stab NA 71.sup.j 330 1727 Comp. ex. 25 ADK Stab NA 21.sup.k 480 1714 Comp. ex. 26 Ciba ® Irgaclear ® 480 1803 XT 386.sup.g Comp. ex. 27 Ciba ® Irgaclear ® 330 1786 XT 386.sup.g Ex. 15 ADK Stab NA 71.sup.j 150 1816 1759.5 Ciba ® Irgaclear ® 180 XT 386.sup.g Ex. 16 ADK Stab NA 71.sup.j 300 1818 1760.8 Ciba ® Irgaclear ® 180 XT 386.sup.g Ex. 17 ADK Stab NA 21.sup.k 300 1831 1746.9 Ciba ® Irgaclear ® 180 XT 386.sup.g .sup.asee table 8. .sup.g,j and ksee table 5. .sup.hthe calculated flexural (elastic) modulus of n ppm of a mixture of a % A and b % B = a % × “flexural (elastic) modulus of n ppm A” + b % × “flexural (elastic) modulus of n ppm B”.
(44) For example the calculated flexural (elastic) modulus of 330 ppm of a mixture of 45% ADK Stab NA 71 and 55% Ciba® Irgaclear® XT 386 (example 15)=45%דflexural (elastic) modulus of 330 ppm ADK Stab NA 71”+55%דflexural (elastic) modulus of 330 ppm Ciba® Irgaclear® XT 386”=45%×1727+55%×1786=1759.5.
(45) As can be seen from table 9 polypropylene homopolymer compositions comprising 150 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 15) show an improved (higher) flexural (elastic) modulus, namely 1816 MPa, compared with the polypropylene homopolymer compositions comprising 330 ppm ADK Stab NA 71 (flexural modulus=1727 MPa, comparative example 24) or 330 ppm Ciba® Irgaclear® XT 386 (flexural modulus=1786 MPa, comparative example 27). The effect is not of additive nature, but synergistic as can be seen when comparing the measured flexural (elastic) modulus (1816 MPa) with the calculated flexural (elastic) modulus (1759.5 MPa).
(46) Table 9 shows the same effect regarding the flexural (elastic) modulus of the polypropylene homopolymer compositions comprising 150 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 15), 300 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 16), respectively, 300 ppm ADK Stab NA 21 and 180 ppm Ciba® Irgaclear® XT 386 (example 17).
(47) Measurement of Haze
(48) The pellets of examples 15 to 17, and comparative examples 23 to 27 are molded at 200° C. to plaques with a thickness of 2 mm using a standard injection molding machine (Arburg 320S).
(49) The hazes the plaques are analysed using a Haze-gard plus instrument (BYK Gardner Gmbh Germany) in accordance with ASTM standard D1003. In this test, haze is commonly defined as that portion of visible light that is scattered at wider angles (2.5°<θ<90°) and is a measure for the turbidity of a sample.
(50) The results are outlined in table 10.
(51) TABLE-US-00010 TABLE 10 Haze Calculated Example No. Nucleating agent [ppm].sup.a [%] Haze.sup.i [%] Comp. ADK Stab NA 71.sup.j 480 83.3 — ex. 23 Comp. ADK Stab NA 71.sup.j 330 86.5 — ex. 24 Comp. ADK Stab NA 21.sup.k 480 79.9 — ex. 25 Comp. Ciba ® Irgaclear ® XT 386.sup.g 480 85.5 — ex. 26 Comp. Ciba ® Irgaclear ® XT 386.sup.g 330 86.0 — ex. 27 Ex. 15 ADK Stab NA 71.sup.j 150 74.1 86.2 Ciba ® Irgaclear ® XT 386.sup.g 180 Ex. 16 ADK Stab NA 71.sup.j 300 69.7 84.1 Ciba ® Irgaclear ® XT 386.sup.g 180 Ex. 17 ADK Stab NA 21.sup.k 300 65.3 82.0 Ciba ® Irgaclear ® XT 386.sup.g 180 .sup.asee table 8. .sup.g,j and ksee table 5. .sup.ithe calculated Haze of n ppm of a mixture of a % A and b % B = a % × “Haze of n ppm A” + b % × “Haze of n ppm B”.
(52) For example the calculated Haze of 330 ppm of a mixture of 45% ADK Stab NA 71 and 55% Ciba® Irgaclear® XT 386 (example 15)=45%דHaze of 300 ADK Stab NA 71”+55%דHaze of 300 ppm Ciba® Irgaclear® XT 386”=45%×86.5+55%×86.0=86.2
(53) As can be seen from table 10 polypropylene homopolymer compositions comprising 150 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 15) show an improved (lower) haze, namely 74.1, compared with the polypropylene homopolymer compositions comprising 330 ppm ADK Stab NA 71 (haze=86.5, comparative example 24) or 330 ppm Ciba® Irgaclear® XT 386 (haze=86.0, comparative example 27). The effect is not of additive nature, but synergistic as can be seen when comparing the measured haze (74.1) with the calculated haze (86.2).
(54) Table 10 shows the same effect regarding haze of the polypropylene homopolymer compositions comprising 150 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 15), 300 ppm ADK Stab NA 71 and 180 ppm Ciba® Irgaclear® XT 386 (example 16), respectively, 300 ppm ADK Stab NA 21 and 180 ppm Ciba® Irgaclear® XT 386 (example 17).
Examples 18 to 21
(55) The mixtures of nucleating agents as indicated in table 11 are mixed with dry powder form polypropylene (PP) random copolymer comprising 4 mole % ethylene (RD 204 CF from Borealis AG, Vienna, Austria) in a high speed mixer (Mixaco Lab CM 12). Under constant nitrogen purge, the mixture is then intensely melt-compounded at 240° C. for 3 minutes at 100 rpm screw speed using a co-rotating laboratory twin-screw extruder (15 cm.sup.3 Micro-Compounder of DSM Xplore). The homogeneous melt is subsequently transferred to a 10 cm.sup.3 Micro-Injector (DSM Xplore), where the melt is injected into a polished mold at a pressure of about 8 bars at 50° C. mold temperature. The resulting circular disks have a diameter of 40 mm and a thickness of 1.0 mm.
(56) Measurement of Haze
(57) The hazes the plaques are analysed using a Haze-gard plus instrument (BYK Gardner Gmbh Germany) at room temperature in accordance with ASTM standard D1003. All haze values are measured at least 24 hours after injection molding.
(58) The results are outlined in table 11.
(59) TABLE-US-00011 TABLE 11 Example No. Nucleating agent [ppm].sup.a Haze [%] Ex. 18 Ciba ® Irgaclear ® XT 386.sup.g 100 20.1 ADK Stab NA 71.sup.j 600 Ex. 19 Ciba ® Irgaclear ® XT 386.sup.g 200 22.9 ADK Stab NA 71.sup.j 1200 Ex. 20 Ciba ® Irgaclear ® XT 386.sup.g 100 19.6 Precursor of ADK Stab NA 71.sup.l 600 lithium stearate 360 Ex. 21 Ciba ® Irgaclear ® XT 386.sup.g 200 16.7 Precursor of ADK Stab NA 71.sup.l 1200 lithium stearate 720 .sup.a, g and jsee table 5. .sup.lPrecursor of ADK Stab NA 71 is