TABLETING OF SPECIFIC POLYMER STABILIZERS

Abstract

The present disclosure relates to a method for manufacturing a tablet including (A) filling a starting material, which is in a solid form, in a first open cavity, which is formed by a first punch and a die, to obtain a second open cavity, which is filled at least partly with the starting material, (B) closing the second open cavity by a second punch to obtain a first dosed cavity, (C) compressing the starting material at a compression temperature below 37° C. by moving at least one out of the first punch and the second punch to obtain a second closed cavity, which has a smaller volume than the first closed cavity, which results in formation of a trapped tablet of the starting material in the second closed cavity, (D) removing the trapped tablet to obtain the tablet, which has a tablet temperature below 37° C. directly after removal.

Claims

1. A method for manufacturing a tablet, which comprises the steps of (A) filling a starting material, which is in a solid form, in a first open cavity, which is formed by a first punch and a die, to obtain a second open cavity, which is filled at least partly, with the starting material, (B) closing the second open cavity by a second punch to obtain a first closed cavity, (C) compressing the starting material at a compression temperature below 37° C. by moving at least one out of the first punch and the second punch to obtain a second closed cavity, which has a smaller volume than the first closed cavity, which results in formation of a trapped tablet of the starting material in the second closed cavity, (D) removing the trapped tablet to obtain the tablet, which has a tablet temperature below 37° C. directly after removal, wherein the steps (A), (B), (C) and (D) are conducted in a tablet press, wherein the starting material is solid at 37° C. and 101.32 KPa and comprises (i) 60 to 100 wt. % of a first polymer stabilizer, which is (i-1) tris(2,4-ditert-butylphenyl) phosphite (CAS-No. 31570-04-4), (i-2) bis(2,4-dicumylphenyl) pentaerythritol diphosphite (CAS-No. 154862-43-8), (i-3) diphosphite (CAS-No. 26741-53-7), (i-4) tetrakis-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionyloxymethyl]methane (CAS-No. 6683-19-8), (i-5) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionic acid stearyl ester (CAS-No. 2082-79-3), (i-6) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-N-[6-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)propanoylamino]hexyl]propanamide (CAS-No. 23128-74-7), (i-7) 3-(3,5-ditert-butyl-4-hydroxyphenyl)-N′-[3-(3,5-ditert-buty-4-hydroxyphenyl)propanoyl]propanehydrazide (CAS-No. 3268-78-8), (i-8) 2-[2-[2-[3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoyloxy]-ethoxy]ethoxy]ethyl 3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoate (CAS-No. 36443-68-2), (i-9) 4-[[3,5-bis[(3,5-ditert-butyl-4-hydroxy-phenyl)methyl]-2,4,6-trimethyl-phenyl]methyl]-2,6-ditert-butyl-phenol (CAS-No, 1709-70-2), (i-10) 1,3,5-tris(3,5-ditert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (CAS-No. 27676-62-6), (i-11) bis[3,3-bis(4′-hydroxy-3′-tert-butylphenyl) butanoic acid] glycol ester (CAS-No. 32509-66-3), (i-12) N,N-dioctadecylhydroxylamine (CAS-No. 123250-74-8), (i-13) dodecyl 3-(3-dodecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 123-28-4), (i-14) octadecyl 3-(3-octadecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 693-36-7), (i-15) pentaerythritol tetrakis[3-dodecylthio proprionate] (CAS-No. 29598-76-3), (i-16) bis(2,2,6,6-tetramethyl-4-piperidyl) decanedioate (CAS-No. 52829-07-9), (i-17) (2-hydroxy-4-octoxy-phenyl)-phenyl-methanone (CAS-No. 1843-05-6), (i-18) 2-tert-butyl-6-(5-chlorobenzotriazol-2-yl)-4-triethyl-phenol (CAS-No. 3896-11-5 (i-19) 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexoxy-phenol (CAS-No. 147315-50-2), (i-20) 2-[4,6-bis(4-phenylphenyl)-1,3,5-triazin-2-yl]-5-(2-ethylhexoxy)phenol (CAS-No, 204583-39-1), (i-21) 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-[3-(2-ethylhexoxy)-2-hydroxy-propoxy]phenol (CAS-No. 137658-79-8), (i-22) butanedioic acid, 1,4-dimethyl ester, polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (CAS-No. 65447-77-0), (i-23) N,N′,N″,N′″-tetrakis-(2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin-6-yl)-1,5,8,12-tetrazadodecane (CAS-No. 122587-07-9), (i-24) N,N′,N″,N′″-tetrakis-(2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin-6-yl)-1,5,8,12-tetrazadodecane (CAS-No. 106990-43-6), (i-25) N,N′-bis-(2,4-bis[N-(1-propoxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin)-N,N′-bis[N-(1-propoxy-2,2,6,6-tetramethylpiperidin-4-yl)]-1,8-diazaoctane (CAS-No. 1271737-36-0), (i-26) poly[[6-[butyl(2,2,6,6-tetramethyl-4-piperidinyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]], α-[[6-[[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl](2,2,6,6-tetramethyl-4-piperidinyl)amino]hexyl](2,2,6,6-tetramethyl-4-piperidinyl)amino]-ω-[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl]- (CAS-No. 195300-91-5), (i-27) poly[[6-[butyl(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)imino]], α-[[6-[[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl](2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]hexyl](2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]-ω-[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl]- (CAS-No. 297748-93-7), (i-28) poly[[6[(1,1,3,3-tetramethylbutyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]] (CAS-No. 71878-19-8), (i-29) tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) butane-1,2,3,4-tetracarboxylate (CAS-No. 91788-83-9), or a mixture thereof, (ii) 0 to 40 wt. % of a second polymer stabilizer, which is zinc stearate, calcium stearate, magnesium stearate or a mixture thereof, (iii) 0 to 34 wt. % of a third polymer stabilizer, which is zinc oxide, hydrotalcite, sodium benzoate or a mixture thereof, (iv) 0 to 20 wt. % of a further ingredient, which is different to the first polymer stabilizer, the second polymer stabilizer and the third polymer stabilizer, wherein the sum of components (i), (ii), (iii) and (iv) is 100 wt. %, wherein the tablet has a weight above 20 mg and below 330 mg and a cross-section dimension above 3 mm and below 18 mm.

2. The method for manufacturing a tablet according to claim 1, wherein the tablet has a geometric form, at which in case a corner is present, each corner possesses only angles directed to the inner side of the tablet above 90° or each corner is convexly rounded, and at which in case of an edge is present, each edge possesses only angles directed to the inner side of the tablet above 90° or each edge is convexly rounded, except in case a corner or an edge originates from an embossed groove.

3.-8. (canceled)

9. The method for manufacturing a tablet according to claim 1, wherein the tablet has a weight above 55 mg and below 200 mg and a cross-section dimension above 4 mm and below 15 mm.

10. (canceled)

11. The method for manufacturing a tablet according to claim 1, wherein the starting material has a mean particle size above 15 μm and below 1000 μm as determined by light scattering.

12. The method for manufacturing a tablet according to claim 1, wherein the starting material has a bulk density above 300 g/L and below 950 g/L as determined by DIN EN ISO 17892-3.

13. The method for manufacturing a tablet according to claim 1, wherein the compressing at step (C) takes place with a compression pressure above 90 MPa and below 600 MPa.

14. The method for manufacturing a tablet according to claim 1, wherein the steps (A), (B), (C) and (D) are conducted at a temperature below 37° C.

15. The method for manufacturing a tablet according to claim 1, wherein the compression temperature is below 32° C. and the tablet temperature is below 32° C.

16. The method for manufacturing a tablet according to claim 1, wherein the tablet or a plurality of tablets is not sieved.

17. The method for manufacturing a tablet according to claim 1, wherein the tablet press is an eccentric tablet press or a rotary tablet press.

18. A tablet, which is solid at 37° C. and 101.32 KPa comprises (i) 60 to 100 wt. % of a first polymer stabilizer, which is (i-1) tris(2,4-ditert-butylphenyl) phosphite (CAS-No. 31570-04-4), (i-2) bis(2,4-dicumylphenyl) pentaerythritol diphosphite (CAS-No. 154862-43-8), (i-3) bis(2,4-ditert-butylphenyl)pentaerythritol diphosphite (CAS-No. 2674-53-7), (i-4) tetrakis-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionyloxymethyl]methane (CAS-No. 6683-19-8), (i-5) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionic acid stearyl ester (CA 5-No. 2082-79-3), (i-6) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-N-[6-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)propanoylamino]hexyl]propanamide (CAS-No. 23128-74-7), (i-7) 3-(3,5-ditert-butyl-4-hydroxyphenyl)-N′-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyl]propanehydrazide (CAS-No. 3268-78-8), (i-8) 2-[2-[2-[3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoyloxy]-ethoxy]ethoxy]ethyl 3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoate (CAS-No. 36443-68-2), (i-9) 4-[[3,5-bis[(3,5-ditert-butyl-4-hydroxy-phenyl)methyl]-2,4,6-trimethyl-phenyl]methyl]-2,6-ditert-butyl-phenol (CAS-No, 1709-70-2), (i-10) 1,3,5-tris(3,5-ditert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (CAS-No. 27676-62-6), (i-11) bis[3,3-bis(4′-hydroxy-3′-tert-butylphenyl) butanoic acid] glycol ester (CAS-No. 32509-66-3), (i-12) N,N-dioctadecylhydroxylamine (CAS-No. 123250-74-8), (i-13) dodecyl 3-(3-dodecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 23-28-4), (i-14) octadecyl 3-(3-octadecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 693-36-7), (i-15) pentaerythritol tetrakis[3-dodecylthio proprionate] (CAS-No. 29598-76-3), (i-16) bis(2,2,6,6-tetramethyl-4-piperidyl) decanedioate (CAS-No. 52829-07-9), (i-17) (2-hydroxy-4-octoxy-phenyl)-phenyl-methanone (CAS-No. 1843-05-6), (i-18) 2-tert-butyl-6-(5-chlorobenzotriazol-2-yl)-4-triethyl-phenol (CAS-No. 3896-1 (i-19) 2-(4,6-diphenyl-1,3,5-triazin-2-yl-5-hexoxy-phenol (CAS-No. 147315-50-2), (i-20) 2-[4,6-bis(4-phenylphenyl)-1,3,5-triazin-2-yl]-5-(2-ethylhexoxy)phenol (CAS-No, 204583-39-1), (i-21) 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-[3-(2-ethylhexoxy)-2-hydroxy-propoxy]phenol (CAS-No. 137658-79-8), (i-22) butanedioic acid, 1,4-dimethyl ester, polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol (CAS-No. 65447-77-0), (i-23) N,N′,N″,N′″-tetrakis-(2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin-6-yl)-1,5,8,12-tetrazadodecane (CAS-No. 122587-07-9), (i-24) N,N′,N″,N′″-tetrakis-(2,4-bis[N-(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin-6-yl)-1,5,8,12-tetrazadodecane (CAS-No. 106990-43-6), (i-25) N,N′-bis-(2,4-bis[N-(1-propoxy-2,2,6,6-tetramethylpiperidin-4-yl)-butylamino]-1,3,5-triazin)-N,N′-bis[N-(1-propoxy-2,2,6,6-tetramethylpiperidin-4-yl)]-1,8-diazaoctane (CAS-No. 1271737-36-0), (i-26) poly[[6-[butyl(2,2,6,6-tetramethyl-4-piperidinyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]], α-[[6-[[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl](2,2,6,6-tetramethyl-4-piperidinyl)amino]hexyl](2,2,6,6-tetramethyl-4-piperidinyl)amino]-ω-[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl]- (CAS-No. 195300-91-5), (i-27) poly[[6-[butyl(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)imino]], α-[[6-[[4,6-bis(dibutyl amino)-1,3,5-triazin-2-yl](2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]hexyl](2,2,6,6-tetramethyl-1-propoxy-4-piperidinyl)amino]-ω-[4,6-bis(dibutylamino)-1,3,5-triazin-2-yl]-(CAS-No. 297748-93-7), (i-28) poly[[6-[(1,1,3,3-tetramethylbutyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]] (CAS-No. 71878-19-8), (i-29) tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl) butane-1,2,3,4-tetracarboxylate (CAS-No. 91788-83-9), or a mixture thereof, (ii) 0 to 40 wt. % of a second polymer stabilizer, which is zinc stearate, calcium stearate, magnesium stearate or a mixture thereof, (iii) 0 to 34 wt. % of a third polymer stabilizer, which is zinc oxide, hydrotalcite, sodium benzoate or a mixture thereof, (iv) 0 to 20 wt. % of a further ingredient, which is different to the first polymer stabilizer, the second polymer stabilizer and the third polymer stabilizer, wherein the sum of components (i), (ii), (iii) and (iv) is 100 wt. %, wherein the tablet has a weight above 20 mg and below 330 mg and a cross-section dimension above 3 mm and below 18 mm.

19. The tablet according to claim 18, wherein the tablet has a geometric form, at which in case a corner is present, each corner possesses only angles directed to the inner side of the tablet above 90° or each corner is convexly rounded, and at which in case of an edge is present, each edge possesses only angles directed to the inner side of the tablet above 90° or each edge is convexly rounded, except in case a corner or an edge originates from an embossed groove.

20. The tablet according to claim 18, wherein the first polymer stabilizer is (i-1) tris(2,4-ditert-butylphenyl) phosphite (CAS-No. 31570-04-4), (i-4) tetrakis-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionyloxymethyl]methane (CAS-No. 6683-19-8), (i-5) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionic acid stearyl ester (CAS-No. 2082-79-3), (i-6) 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-N-[6-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)propanoylamino]hexyl]propanamide (CAS-No. 23128-74-7), (i-7) 3-(3,5-ditert-butyl-4-hydroxyphenyl)-N′-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyl]propanehydrazide (CAS-No. 32687-78-8), (i-8) 2-[2-[2-[3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoyloxy]-ethoxy]ethoxy]ethyl 3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propanoate (CAS-No. 36443-68-2), (i-9) 4-[[3,5-bis[(3,5-ditert-butyl-4-hydroxy-phenyl)methyl]-2,4,6-trimethyl-phenyl]methyl]-2,6-ditert-butyl-phenol (CAS-No. 1709-70-2), (i-10) 1,3,5-tris(3,5-ditert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (CAS-No. 27676-62-6), (i-12) N,N-dioctadecylhydroxylamine (CAS-No, 123250-74-8), (i-13) dodecyl 3-(3-dodecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 123-28-4), (i-14) octadecyl 3-(3-octadecoxy-3-oxo-propyl)sulfanylpropanoate (CAS-No. 693-36-7), (i-16) bis(2,2,6,6-tetramethyl-4-piperidyl) decanedioate (CAS-No. 52829-07-9), or a mixture thereof.

21. (canceled)

22. The tablet according to claim 18, wherein the further ingredient (iv) contains less than 3 wt. % of polymeric components, which are different to the first primary polymer stabilizers (i-22), (i-26), (i-27) and (i-28), based on the sum of components (i), (ii), (iii) and (iv), which is 100 wt. %.

23. The tablet according to claim 18, wherein the further ingredient (iv) contains less than 9 wt. % of a binder, which is a molecule comprising an alkyl or alkenyl group with more than 14 carbon atoms and is different to the first primary polymer stabilizers (i-5), (i-12) and (i-14) and the secondary polymer stabilizers zinc stearate, calcium stearate and magnesium stearate, based on the sum of components (i), (ii), (iii) and (iv), which is 100 wt, iii.

24. The tablet according to claim 18, wherein the secondary polymer stabilizer (ii) is contained in an amount of 0 to 29 wt. % based on the sum of components (i), (ii), (iii) and (iv), which is 100 wt. %.

25. The tablet according to claim 18, wherein the further ingredient (iv) is contained in an amount of 0 to 9 wt. % based on the sum of components (i), (ii), (iii) and (iv), which is 100 wt. %.

26. The tablet according to claim 18, wherein the tablet has a weight above 55 mg and below 200 mg and a cross-section dimension above 4 mm and below 15 mm.

27. A method for manufacturing a stabilized polymer, which comprises the steps of (AP) dosing a tablet according to claim 18 into a polymer to obtain a tablet-polymer mixture, (BP) exposing the tablet-polymer mixture to a temperature in the range of 120 to 340° C. under mechanical stirring to obtain a stabilized polymer, wherein the polymer is a polyolefin, a polystyrene or a mixture thereof.

28. (canceled)

29. (canceled)

30. (canceled)

31. A tablet-polymer mixture comprising the components (a) a tablet according to claim 18, and (b) a polymer, which is a polyolefin, a polystyrene or a mixture thereof, wherein the polymer is in the form of pellets and the pellets have an average pellet weight above 20 mg and below 330 mg and an average pellet cross-section dimension above 3 mm and below 18 mm, and wherein component (a) is contained in an amount from 0.01 wt. % to 5 wt. % based on the amount of component (b).

32. (canceled)

Description

[0379] FIG. 1 shows a specific geometric form of a tablet which is round in top view (on the left) and consisting out of two parallel lines of a same length as sides opposing each other and two convex curves as sides opposing each other (=biconvex) in side view (on the right). The two parallel lines in side view capped by the convex curves are only drawn to indicate the location of the circle shown at top view.

[0380] FIG. 2 shows tablets from example TA-1-2 out of starting material SM-2 with a pocket rule including a centi-/millimeter scale in the background. FIG. 2 is an enlarged extract from FIG. 7.

[0381] FIG. 3 shows tablets from example TA-1-3 out of starting material SM-3 with a pocket rule including a centi-/millimeter scale in the background. FIG. 3 is an enlarged extract from FIG. 6.

[0382] FIG. 4 shows flakes as described at E-1) out of starting material SM-3 with a pocket rule including a centi-/millimeter scale in the background. FIG. 4 is an enlarged extract from FIG. 6.

[0383] FIG. 5 shows pastilles as described at E-2) out of starting material SM-2 with a pocket rule including a centi-/millimeter scale in the background. FIG. 5 is an enlarged extract from FIG. 7.

[0384] FIG. 6 shows tablets from example TA-1-3 (on the left) and flakes as described at E-1) (on the right) out of starting material SM-3 with a pocket rule including a centi-/millimeter scale in the background.

[0385] FIG. 7 shows tablets from example TA-1-2 (on the left) and pastilles as described at E-2) (on the right) out of starting material SM-2 with a pocket rule including a centi-/millimeter scale in the background.

[0386] The following examples illustrate further the invention without limiting it. Percentage values are percentage by weight if not stated differently.

A) Methods for Characterization

[0387] Mean particle size is determined, if not otherwise stated, by a Mastersizer 2000 from the company Malvern Panalytical via a light scattering. Analysis is done based on Mie and Fraunhofer scattering model under dry dispersion pressure of 0.2 bar.

[0388] Particle size for materials, which contain particles >0.8 mm, can also be measured with a vibrating sieve shaker (e.g. Fritsch Analysette a-3 vibratory sieve shaker Model «PRO») with sieves in the range of 0.1 mm up to 4.0 mm depending on the coarse fraction of the material. Sieving time is 1 minute and sieving amplitude is 1 mm.

[0389] Bulk density is measured complying to the DIN EN ISO 17892-3.

[0390] Tablet weight (m), tablet diameter (d), tablet height (h) and side crush strength (SCS) of the same tablet are characterized with a commercially 4 in 1 tablet hardness testing equipment, i.e.

[0391] PharmaTest WHT2 from the company Pharma Test Apparatebau AG. Tensile strength (a) by diametral compression of a tablet [in MPa] is calculated according to

σ=2.Math.SCS.Math.10.sup.6/π.Math.d.Math.h.

[0392] The Norner abrasion test is a test using a vibrating sieve shaker and glass beads to mechanically treat the tested form. An initial sieve analysis for is conducted for 1 minute followed by further sieving using glass balls on the sieve decks to mechanically impact the material and measure the change of the sieve fractions after 5, 10 and 20 minutes. Sieves selected are bottom up: 200 μm, 500 μm, 1 mm, 1.6 mm, 2.5 mm and 4 mm. The used glass balls (company Sigmund Lindner GmbH, type P) are of 16 mm±0.02 mm, weight 5.36 g/glass ball and made of soda lime glass with fine matt surface.

[0393] The test procedure is as follow:

1. The sieve shaker without glass beads is charged with 50 g of a sample and the sieving with amplitude 1 mm is conducted for 1 minute. Measuring of mass on each sieve tray and sieve pan
2. Add 8 glass balls on sieve 500 μm; 9 glass balls on sieve 1.0 mm, 10 on sieve 1.6 mm and 11 on sieve 2.5 mm. Proceed sieving for 5 minutes then measure mass on each sieve tray and sieve pan.
3. Proceed sieving for another 5 minutes, repeat weighing procedure.
4. Proceed sieving for another 10 minutes, repeat weighing procedure.

[0394] A Retsch Sieve Shaker AS 200 control from the company Retsch GmbH is used as sieve shaker.

[0395] Total fines are the sum of all material, which is collected from bottom plate, 200 μm mesh sieve and 500 μm mesh sieve. Accordingly, the fragments of a sample, which are generated under attrition stress and fall through a 500 μm mesh sieve (<500 μm), are considered fines. The particle size fraction in wt. % <500 μm after 20 minutes is the key result (Norner value) to deter-mine abrasion and impact resistance of the tested form. The range of results can vary from 0% for extremely stable to 100% for extremely unstable.

[0396] Differential scanning calorimetry (DSC) analysis is done by a constant heating rate of 20 K/min.

[0397] Melt flow index of a polymer is measured according to ISO 1133 on a Goettfert MI-Robo with the specifically stated parameters.

[0398] Yellowness index (YI) is measured according to DIN 6167 and delta E of yellowness index (YI) is measured according to DIN 6174.

B) Starting Material

SM-1: Irganox 1010

[0399] Irganox 1010 (TM, commercially available from BASF SE, melting range of 110-125° C.), which contains tetrakis-[3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionyloxymethyl]methane (CAS-No. 6683-19-8) as depicted below,

##STR00028##

in the form of a powder, i.e. a loose bulk material with a bulk density of 643 g/L and a mean particle size of 260 μm.

SM-2: Irganox 1076

[0400] Irganox 1076 (TM, commercially available from BASF SE, melting range of 50-55° C.), which contains 3-(3,5-ditert-butyl-4-hydroxy-phenyl)-propionic acid stearyl ester (CAS-No. 2082-79-3) as depicted below

##STR00029##

in the form of a powder, i.e. a loose bulk material with a bulk density of 520 g/L and a mean particle size of 748 μm.

SM-3: Irgafos 168

[0401] Irgafos 168 (TM, commercially available from BASF SE, melting range of 180-183° C.), which contains tris(2,4-ditert-butylphenyl) phosphite (CAS-No. 31570-04-4) as depicted below

##STR00030##

in the form of a powder, i.e. a loose bulk material with a bulk density of 467 g/L and a mean particle size of 400 μm.

SM-4: Irganox MD 1024

[0402] Irganox MD 1024 (TM, commercially available from BASF SE, melting range of 221-232° C.), which contains 3-(3,5-ditert-butyl-4-hydroxyphenyl)-N′-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyl]propanehydrazide (CAS-No. 32687-78-8) as depicted below

##STR00031##

in the form of a powder, i.e. a loose bulk material with a bulk density of 384 g/L and a mean particle size of 46 μm.

SM-5: Irganox 3114

[0403] Irganox 3114 (TM, commercially available from BASF SE, melting range of 218-223° C.), which contains 1,3,5-tris(3,5-ditert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (CAS-No. 27676-62-6) as depicted below

##STR00032##

in the form of a powder, i.e. a loose bulk material with a bulk density of 561 g/L and a mean particle size of 82 μm.

SM-6: Tinuvin 770

[0404] Tinuvin 770 (TM, commercially available from BASF SE, melting range of 81-85° C.), which contains bis(2,2,6,6-tetramethyl-4-piperidyl)decandioate (CAS-No. 52829-07-9) as depicted below

##STR00033##

in the form of a powder, i.e. a loose bulk material with bulk density of 586 g/L and a mean particle size of 347 μm.

Sm-7: Zinc Stearate

[0405] Zinc stearate (commercially available, melting range of around 123° C., CAS-No. 557-05-1) in the form of a powder, i.e. a loose bulk material with a bulk density of 470 g/L and a mean particle size of 21 μm.

SM-8: Calcium Stearate

[0406] Calcium stearate (commercially available, melting range of 140-160° C., CAS-No. 1592-23-0) in the form of a powder, i.e. a loose bulk material with a bulk density of 521 g/L and a mean particle size of 325 μm.

SM-9: Zinc Oxide

[0407] Zinc oxide (commercially available, melting range >400° C., CAS-No. 1314-13-2) in the form of a powder, i.e. a loose bulk material with a bulk density of 880 g/L and a mean particle size of 22 μm.

SM-10: Blend of SM-1 (50) and SM-3 (50)

[0408] SM-10 is obtained in the form of a powder by blending 50 wt. % of SM-1 (Irganox 1010) and 50 wt. % of SM-3 (Irgafos 168) in a free fall or drum mixer, i.e. a drum hoop mixer from company J. Engelsmann AG, which is filled to 50% of its drum volume, at 40 rpm for 10 min at 25° C. Sample size is 250 g. The melting range of SM-10 is above 37° C. at 101.32 kPa.

[0409] In the following further starting material blends, i.e. SM-11, SM-12, SM-13, SM-14, SM-15, SM-16, SM-17, SM-18, SM-19 and SM-20 are prepared with the same method as starting material blend SM-10 differing only in compositions unless stated otherwise. The melting ranges are above 37° C. at 101.32 kPa.

SM-11: Blend of SM-3 (80) and SM-2 (20)

[0410] SM-11 is obtained in the form of a powder by blending 80 wt. % of SM-3 (Irgafos 168) and 20 wt. % of SM-2 (Irganox 1076).

SM-12: Blend of SM-1 (33) and SM-3 (67)

[0411] SM-12 is obtained in the form of a powder by blending 33 wt. % of SM-1 (Irganox 1010) and 67 wt. % of SM-3 (Irgafos 168).

SM-13: Blend of SM-1 (18.8), SM-3 (18.8) and SM-6 (62.4)

[0412] SM-13 is obtained in the form of a powder by blending 18.8 wt. % of SM-1 (Irganox 1010), 18.8 wt. % of SM-3 (Irgafos 168) and 62.4 wt. % of SM-6 (Tinuvin 770).

SM-14: Blend of SM-3 (84) and SM-4 (16)

[0413] SM-14 is obtained in the form of a powder by blending 84 wt. % of SM-3 (Irgafos 168) and 16 wt. % of SM-4 (Irganox MD 1024).

SM-15: Blend of SM-1 (50) and SM-2 (50)

[0414] SM-15 is obtained in the form of a powder by blending 50 wt. % of SM-1 (Irganox 1010) and 50 wt. % of SM-4 (Irganox 1076).

SM-16: Blend of SM-3 (78.4) and SM-5 (21.6)

[0415] SM-16 is obtained in the form of a powder by blending 78.4 wt. % of SM-3 (Irgafos 168) and 21.6 wt. % of SM-5 (Irganox 3114).

SM-17: Blend of SM-3 (67) and SM-2 (33)

[0416] SM-17 is obtained in the form of a powder by blending 67 wt. % of SM-3 (Irgafos 168) and 33 wt. % of SM-2 (Irganox 1076).

SM-18: Blend of SM-1 (24), SM-3 (48) and SM-8 (28)

[0417] SM-18 is obtained in the form of a powder by blending 24 wt. % of SM-1 (Irganox 1010), 48 wt. % of SM-3 (Irgafos 168) and 28 wt. % of SM-8 (calcium stearate).

SM-19: Blend of SM-1 (20), SM-3 (60) and SM-7 (20)

[0418] SM-19 is obtained in the form of a powder by blending 20 wt. % of SM-1 (Irganox 1010), 60 wt. % of SM-3 (Irgafos 168) and 20 wt. % of SM-7 (zinc stearate).

SM-20: Blend of SM-2 (66.7) and SM-9 (33.3)

[0419] SM-20 is obtained in the form of a powder by blending 66.7 wt. % of SM-2 (Irganox 1076) and 33.3 wt. % of SM-9 (zinc oxide).

C) Tableting of Starting Material

TA-1: Tableting of SM-1 to SM-3 and SM-10 to SM-20 on an Eccentric Tablet Press

[0420] The applied tablet press is an eccentric tablet press with one cavity for compressing (so-called single punch machine), i.e. a model XP1 from company Korsch AG. Punches of the EU D type (Euro standard) of 6 mm biplane and the respective die are installed at the model XP1. All the tableting examples of table C-1-1 with all their steps take place at room temperature between 20-25° C. No external heat energy is introduced to the starting material during tableting. The starting material as stated in table C-1-1, which has room temperature and is in a solid form, is filled into the feeding shoe of the model XP1. The open cavity formed by the die and the lower punch is filled via the feeding shoe with the starting material. A second punch closes the filled cavity. In the following compression step conducted at room temperature, the punches are moving towards each other and the compression pressure is reached. This results in formation of the tablet by compaction of the starting material in the cavity formed by the die and the two punches. The formed tablet is removed directly afterwards by removal of one punch and ejection via the other punch. The removed tablet possesses room temperature directly after removal. Applied tablet press parameters at the model XP1 for a respective starting material are stated in table C-1. The parameters of the tablets obtained at TA-1 are stated in table C-2.

TABLE-US-00001 TABLE C-1 tablet press parameters at TA-1 maximal maximal compression position position stroke example starting pressure of lower of upper rate No. material [MPa] punch [mm] punch [mm] [min.sup.−1] TA-1-1 .sup.a) SM-1 455 5 4 15 TA-1-2 .sup.a) SM-2 209 7 5 15 TA-1-3 .sup.a) SM-3 440 7 5 15 TA-1-4 .sup.a) SM-10 385 9 5 15 TA-1-5 .sup.a) SM-11 440 9 5 15 TA-1-6 .sup.a) SM-12 331 9 5 15 TA-1-7 .sup.a) SM-13 442 6 4 15 TA-1-8 .sup.a) SM-14 99 9 5 15 TA-1-9 .sup.a) SM-15 391 6 4 15 TA-1-10 .sup.a) SM-16 293 9 6 15 TA-1-11 .sup.a) SM-17 432 9 6 15 TA-1-12 .sup.a) SM-18 425 6 4 15 TA-1-13 .sup.a) SM-19 391 6 4 15 TA-1-14 .sup.a) SM-20 302 7 5 15 Footnotes: .sup.a) according to the invention

[0421] Position of punches are set manually for each SM depending on factors such as product bulk material and flow behavior while filling the die. Target is to yield a tablet with a tablet height of at least 2.5 mm.

[0422] The parameters of the tablets obtained at TA-1 are stated in table C-2. Pictures of tablets from TA-1-2 and TA-1-3 are depicted in FIG. 2/FIG. 7 and FIG. 3/FIG. 6.

TABLE-US-00002 TABLE C-2 parameters of tablets obtained at TA-1 average tensile fines (<500 μm) example starting weight height strength after 20 min No. material [mg] [mm] [MPa] Norner test [%] TA-1-1 .sup.a) SM-1 69 2.5 2.3 9 TA-1-2 .sup.a) SM-2 86 3.3 1.2 1 TA-1-3 .sup.a) SM-3 92 3.5 0.8 21 TA-1-4 .sup.a) SM-10 137 4.9 1.0 4 TA-1-5 .sup.a) SM-11 122 4.6 0.8 53 TA-1-6 .sup.a) SM-12 136 4.9 0.8 9 TA-1-7 .sup.a) SM-13 95 3.5 1.1 11 TA-1-8 .sup.a) SM-14 115 4.7 0.3 61 TA-1-9 .sup.a) SM-15 91 3.3 1.6 1 TA-1-10 .sup.a) SM-16 139 5.1 0.9 20 TA-1-11 .sup.a) SM-17 129 4.8 0.7 26 TA-1-12 .sup.a) SM-18 79 3.1 0.3 97 TA-1-13 .sup.a) SM-19 88 3.3 0.6 30 TA-1-14 .sup.a) SM-20 112 3.5 0.8 19 Footnotes: .sup.a) according to the invention

D) Differential Scanning Calorimetry of a Tablet

[0423] Differential scanning calorimetry (DSC) analysis is done for determining melting behavior. The melting behavior of starting materials and tablets out of the starting materials are compared as shown in table D-1.

TABLE-US-00003 TABLE D-1 melting behavior of a tablet and its starting material example maxima during No. sample DSC [° C.] D-1-1 .sup.b) SM-10 in powder form 118.2; 179.1 D-1-2 .sup.b) SM-10 in powder form initially heated and 39 cooled .sup.c) and then measured D-1-3 .sup.a) tablet TA-1-4 out of SM-10 117.4; 176.8 D-1-4 .sup.b) SM-16 in powder form 183.7 D-1-5 .sup.b) SM-16 in powder form initially heated and 39 cooled .sup.c) and then measured D-1-6 .sup.a) tablet TA-1-10 out of SM-16 180.7 Footnotes: .sup.a) according to the invention .sup.b) comparative .sup.c) initial DSC sample is exposed to a first heating with a constant heating rate of 20 K/min and cooling circle and then DSC measurement of the exposed DSC sample

[0424] Table D-1 shows that there is not a significant change of melt behaviors determined by DSC for the starting materials SM-10 (blend of 50 wt. % SM-1 [Irganox 1010]) and 50 wt. % SM-3 [Irgafos 168]) and SM-16 (blend of 78.4% SM-3 [Irgafos 168] and 21.6 wt. % SM-5 [Irganox 3114]) and the tablets TA-1-4 out of SM-10 and TA-1-10 out of SM-16. If the starting materials SM-10 and SM-16 in powder form are once molten and cooled again, then only a glass transition phase at 39° C. is observed. The absence of a significant change of melt behavior at the tablets TA-1-4 and TA-1-10 indicates that there has not been an exposure to external heat energy.

E) Generation of Forms Different to a Tablet

[0425] E-1): Flakes from a Roll Compaction Process

[0426] Starting materials SM-1, SM-3 and SM-10 are press-agglomerated via a roll compaction process to obtain comparative flakes. The respective starting material in its powder form in a hop-per is force-fed via a feeding screw into a compaction zone. The compaction zone is formed by a remaining gap between two rolls with slightly scratched surfaces, which are rotating towards each other. A suitable laboratory roll compactor is for example model WP 50N/75 (roll diameter: 150 mm, roll length: 75 mm, maximum press capacity: 12.8 t, maximum linear load: 1.71 t/cm) from the company Alexanderwerk GmbH in Germany. The compacted starting material, which leaves the compaction zone as plates, is granulated via a sieve granulator to create free flowing flakes. A suitable sieve granulator is model GLA-ORV-0215 from company Frewitt Ltd from Switzerland. At this step, plates are granulated to fragments with a 4 mm mesh sieve acting as a screen. These fragments of sizes below 4 mm are further sieved into 2 categories by a 1 mm mesh sieve acting as a screen. Two sieving fractions are obtained, i.e. the desired flakes and fines. Accordingly, the fines are those fragments of sizes below 4 mm, which pass also the 1 mm mesh sieve. Depending on the initial hardness of the plates, the sieving fraction of fines amounts from 10 wt. % up to 30 wt. % of the originally fed starting material. This sieving fraction of fines needs to be roll-compacted again. During the roll compaction process, mechanical stress applied from the rolls onto the starting material is the only energy source exerted to the starting material during the compaction. No additional external heat transfer occurs during the roll compaction including the granulation with the sieve granulator. The compaction rolls are cooled to avoid material sticking to the surface. The roll compaction of SM-1, SM-3 and SM-10 takes place at atmospheric pressure with temperature ranging from 20° C. to 30° C. Table E-1 shows the obtained mean particles sizes and bulk densities.

TABLE-US-00004 TABLE E-1 mean particle size and bulk density of flakes bulk mean Starting density particle flake sample material [g/L] size .sup.c) [mm] E-1-1 .sup.b) SM-1 597 1.953 E-1-2 .sup.b) SM-3 514 1.392 E-1-3 .sup.b) SM-10 532 1.548 Footnotes: .sup.b) comparative .sup.c) mean particle size determined by a vibrating sieve shaker as decribed under A)

[0427] A picture of flakes out of SM-3 is depicted at FIG. 4/FIG. 6. The picture at FIG. 6 shows that the flakes produced via roll compaction out of SM-3 have a less defined shape in comparison to tablets out of SM-3.

E-2): Pastilles from a Rotoform Granulation Process

[0428] For comparison, starting material SM-2 is compacted by a rotoform granulation process to obtain comparative pastilles. The starting material SM-2 comes directly from the Synthesis as a melt. The melt is treated in a scraped cooler to generate crystal seeds that are required to initiate crystallization in the rotoform granulation process. A pump delivers the molten product to the rotoform system (e.g. from IPCO former Sandvik) via heated pipes. The rotoform itself consists of a heated cylindrical stator, which is supplied with liquid product, and a perforated rotating shell that turns concentrically around the stator. Drops of the product are deposited by the nozzle bar across the whole operating width of a continuously running stainless steel belt. The rotation speed of the rotofrom is synchronized with the speed of the belt to allow a gentle deposition of the liquid droplets onto the moving belt. The belt is cooled by water sprayed underneath. The product droplets solidify or crystallize on the cooling belt and pastilles are obtained. The obtained pastilles have a diameter of around 5 mm and a height of 0.5 to 1 mm.

TABLE-US-00005 TABLE E-2 mean particle size and bulk density of pastilles bulk starting density pastille sample material [g/L] E-2-1 .sup.b) SM-2 300 Footnotes: .sup.b) comparative

[0429] A picture of pastilles out of SM-2 is depicted at FIG. 5/FIG. 7. The picture at FIG. 7 shows that the pastilles out of SM-2 have a less defined shape in comparison to tablets out of SM-2.

F) Comparison for Attrition Resistance

[0430] For comparison of the attrition resistance, obtained tablets from a starting material are compared for attrition resistance to comparative flakes obtained at E-1) as shown in table F-1.

TABLE-US-00006 TABLE F-1 attrition resistance of a tablet and a flake fines (<500 μm) example after 20 min No. sample Norner test [%] F-1-1 .sup.a) tablets as obtained from TA-1-1 out of SM-1 9 F-1-2 .sup.b) flakes as obtained from E-1-1 out of SM-1 97 F-1-3 .sup.a) tablets as obtained from TA-1-3 out of SM-3 21 F-1-4 .sup.b) flakes as obtained from E-1-2 out of SM-3 98 F-1-5 .sup.a) tablets as obtained from TA-1-4 out of 4 SM-10 F-1-6 .sup.b) flakes as obtained from E-1-3 out of SM-10 96 Footnotes: .sup.a) according to the invention .sup.b) comparative

[0431] Table F-1 shows that the starting materials SM-1, SM-3 and SM-10 in the form of a tablet are more stable towards attrition than in the form of a flake.

[0432] For comparison of the attrition resistance, obtained tablets from a starting material are compared for attrition resistance to comparative pastilles obtained at E-2 as shown in table F-2.

TABLE-US-00007 TABLE F-2 attrition resistance of a tablet and a pastille fines (<500 μm) example after 20 min No. sample Norner test [%] F-2-1 .sup.a) tablets from TA-1-2 out of SM-2 1 F-2-2 .sup.b) pastilles from E-2-1 out of SM-2 14 Footnotes: .sup.a) according to the invention .sup.b) comparative

[0433] Table F-2 shows that the starting material SM-2 in the form of a tablet is more stable towards attrition than in the form of a pastille.

G) Stabilization of a Linear Low-Density Polyethylene

[0434] G-1) Incorporation of Polymer Stabilizer into a Linear Low-Density Polyethylene

[0435] A blend of a linear low-density polyethylene in pellet form and a stabilizer in tablet form is compared to a blend of the linear low-density polyethylene in powder form and the stabilizer in powder form.

[0436] Linear low-density polyethylene in pellet form:

[0437] LLDPE (Dowlex SC 2108G (TM Dow Chemicals), melt flow index (230° C./2.16 kg) 2.6 g/10 min, pellet size: average diameter 3.7 mm, average height 4.0 mm; average pellet weight 33 mg)

[0438] Linear low-density polyethylene in powder form:

[0439] LLDPE (Dowlex SC 2108G (TM Dow Chemicals), pellets ground with a Pallman grinder to a powder with an average particle size as determined by a Camsizier P4: D50=1.1 mm, D90=1.9 mm)

[0440] For achieving a mixture with a weight ratio as shown in table G-1, LLDPE in pellet form is mixed with the respective tablet in a Roehnrad Elite 650 mixer at room temperature. LLDPE in powder form is blended with the stabilizer or stabilizer blend in powder form, i.e. the starting material as described at B), in a tumble mixer at room temperature.

[0441] The respective polymer stabilizer mixture as shown in table G-1 is compounded in a twin-screw extruder (Collin 25/42 L/D) at 190° C. under a nitrogen blanket and pelletized. Pellets of stabilized linear low-density polyethylene are obtained.

TABLE-US-00008 TABLE G-1 stabilized linear low-density polyethylene with MFI MFI (190° C./2.16 kg) of stabilized linear mixture used for obtaining low-density example stabilized linear low-density polyethylene pellets No. polyethylene pellets [g/10 min] G-1-1 .sup.b) 99.90% LLDPE .sup.c) (powder) 2.8 0.10% SM-10 (powder) G-1-2 .sup.a) 99.90% LLDPE (pellet) 2.7 0.10% TA-1-4 (tablet out of SM-10) G-1-3 .sup.b) 99.85% LLDPE (powder) 2.7 0.15% SM-20 (powder) G-1-4 .sup.a) 99.85% LLDPE (pellet) 2.6 0.15% TA-1-15 (tablet out of SM-20) G-1-5 .sup.b) 99.90% LLDPE (powder) 2.7 0.10% SM-19 (powder) G-1-6 .sup.a) 99.90% LLDPE (pellet) 2.7 0.10% TA-1-14 (tablet out of SM-19) G-1-7 .sup.b) 99.80% LLDPE (powder) 2.6 0.20% SM-13 (powder) G-1-8 .sup.a) 99.80% LLDPE (pellet) 2.7 0.20% TA-1-7 (tablet out of SM-13) Footnotes: .sup.a) according to the invention .sup.b) comparative .sup.c) Dowlex SC 2108G from the company Dow Chemicals

G-2) Performance of the Stabilized Linear Low-Density Polyethylene

[0442] The melt flow properties of the obtained pellets of stabilized linear low-density polyethylene are measured at 190° C./2.16 kg (melt flow index according to ISO 1133) and the results are shown in table G-1.

[0443] Table G-1 shows that a measured melt flow index of a stabilized linear low-density polyethylene pellet obtained from the pellet-tablet blend is within the same range as the one of the stabilized linear low-density polyethylene pellets obtained from the powder-powder blend.

H) Stabilization of a Polypropylene

[0444] H-1) Incorporation of Polymer Stabilizer into a Polypropylene

[0445] A blend of a polypropylene in pellet form and a stabilizer in tablet form is compared to a blend of the polypropylene in powder form and the stabilizer in powder form.

Polypropylene in Pellet Form:

[0446] PP (HD 120 MO of the company Borealis, melt flow index (230° C./2.16 kg) 8.0 g/10 min, pellet size: average diameter 3.3 mm, average height 4.3 mm; average pellet weight 25 mg)

Polypropylene in Powder Form:

[0447] PP (HD 120 MO of the company Borealis, pellets ground with a Pallman grinder to a powder with an average particle size as determined by a Camsizier P4: D50=1.1 mm, D90=1.6 mm)

[0448] For achieving a composition with a weight ratio as shown in table H-1, PP in pellet form is mixed with the respective tablet in a Roehnrad Elite 650 mixer at room temperature. PP in powder form is blended with the stabilizer or stabilizer blend in powder form, i.e. the starting material as described at B), in a tumble mixer at room temperature.

[0449] The respective polymer stabilizer mixture as shown in table H-1 is compounded in a twin-screw extruder (Collin 25/42 L/D) at 230° C. under a nitrogen blanket and pelletized. Pellets of stabilized polypropylene are obtained.

TABLE-US-00009 TABLE H-1 stabilized polypropylene with MFI MFI (230° C./2.16 kg) of stabilized example mixture used for obtaining polypropylene pellets No. stabilized polypropylene pellets [g/10 min] H-1-1 .sup.b) 99.80% PP .sup.c) (powder) 8.5 0.20% SM-10 (powder) H-1-2 .sup.a) 99.80% PP (pellet) 8.7 0.20% TA-1-4 (tablet out of SM-10) H-1-3 .sup.b) 99.80% PP (powder) 9.1 0.20% SM-20 (powder) H-1-4 .sup.a) 99.80% PP (pellet) 9.1 0.20% TA-1-15 (tablet out of SM-20) H-1-5 .sup.b) 99.90% PP (powder) 9.0 0.10% SM-19 (powder) H-1-6 .sup.a) 99.90% PP (pellet) 9.1 0.10% TA-1-14 (tablet out of SM-19) Footnotes: .sup.a) according to the invention .sup.b) comparative .sup.c) HD 120 MO from the company Borealis

H-2) Performance of the Stabilized Polypropylene

[0450] The melt flow properties of the obtained pellets of stabilized polypropylene are measured at 230° C./2.16 kg (melt flow index according to ISO 1133) and the results are shown in table H-1.

[0451] Table H-1 shows that a measured melt flow index of a stabilized polypropylene pellet obtained from the pellet-tablet blend is within the same range as the one of the stabilized polypropylene pellet obtained from the powder-powder blend.

I) Stabilization of an ABS Polymer

[0452] I-1) Incorporation of Polymer Stabilizer into an ABS Polymer

[0453] A blend of an ABS (acrylonitrile-butadiene-styrene) polymer in pellet form and a stabilizer in tablet form is compared to a blend of the ABS polymer in powder form and the stabilizer in powder form.

ABS Polymer in Pellet Form:

[0454] ABS polymer (Terluran GP-22 (TM of Styrolution), melt flow index of pellet (220° C./10 kg) 19.0 g/10 min, pellet size: average diameter 3.3 mm, average height 4.6 mm; average pellet weight 30 mg)

ABS Polymer in Powder Form:

[0455] ABS polymer (Terluran GP-22 (TM of Styrolution), pellets ground with a Pallman grinder to a powder with an average particle size as determined by a Camsizier P4: D50=0.7 mm, D90=1.2 mm, melt flow index of powder (220° C./10 kg) 20.5 g/10 min)

[0456] It is remarked that the grinding of the ABS polymer pellets towards a powder leads to a degradation as indicated by a melt flow index of 20.5 for the powder versus 19.0 for the pellets. A higher melt flow index indicates a lower viscosity of the heated polymer and thus for example a degradation of long polymeric chain into smaller polymeric chains.

[0457] For achieving a composition with a weight ratio as shown in table I-1, ABS polymer in pellet form is mixed with the respective tablet in a Roehnrad Elite 650 mixer at room temperature. ABS polymer in powder form is blended with the stabilizer or stabilizer blend in powder form, i.e. the starting material as described at B), in a tumble mixer at room temperature. The pellet-tablet mixture and the powder-powder mixture are dried before compounding for 3 h at 80° C. (Vacutherm 1600).

[0458] The respective polymer stabilizer mixture as shown in table I-1 is compounded in a twin-screw extruder (Collin 25/42 L/D) at 230° C. under a nitrogen blanket and pelletized. Pellets of stabilized ABS polymer are obtained. The pellets of stabilized ABS polymer are dried before further processing for 3 h at 80° C. (Heliomat 2000 6K).

[0459] Dried pellets of stabilized ABS polymer are injection molded at 230° C. to obtain tensile impact bars of 65×10×2 mm (Engel e-mac 100).

[0460] Dried pellets of stabilized ABS polymer are compression molded at 230° C. for 3 min to obtain plaques (Suter LP 322, plaques of 2 mm thickness).

TABLE-US-00010 TABLE I-1 stabilized ABS polymer with MFI MFI (220° C./10 kg) of stabilized ABS example mixture used for obtaining polymer pellets No. stabilized ABS polymer pellets [g/10 min]) I-1-1 .sup.b) 99.80% ABS polymer .sup.c) (powder) 20.4 0.20% SM-20 (powder) I-1-2 .sup.a) 99.80% ABS polymer (pellet) 19.5 0.20% TA-1-15 (tablet out of SM-20) I-1-3 .sup.b) 99.80% ABS polymer (powder) 20.7 0.20% SM-13 (powder) I-1-4 .sup.a) 99.80% ABS polymer (pellet) 19.6 0.20% TA-1-7 (tablet out of SM-13) I-1-5 .sup.b) 99.90% ABS polymer (powder) 21.2 0.10% SM-19 (powder) I-1-6 .sup.a) 99.90% ABS polymer (pellet) 19.8 0.10% TA-1-14 (tablet out of SM-19) Footnotes: .sup.a) according to the invention .sup.b) comparative .sup.c) Terluran GP-22 from the company Styrolution

I-2) Performance of the Stabilized ABS Polymer

[0461] The melt flow properties of the obtained pellets of stabilized ABS polymer are measured at 220° C./10 kg (melt flow index according to ISO 1133) and the results are shown in table I-1.

[0462] Table I-1 shows that the ground ABS shows always an about one unit higher MFI. This is due to the grinding step. Besides this within a range of +/−0.2 units, the melt flow of an inventive examples versus its respective comparative example is in the same range.

[0463] For weathering, the plaques with a thickness of 2 mm are exposed to artificial weathering according to DIN EN ISO4892-2 cycle 1 (dry) as shown in table I-2. The discoloration of the plaques is determined by measuring the yellowness index and delta E of yellowness index as shown in table I-2 after the stated time periods of artificial weathering.

TABLE-US-00011 TABLE I-2 stabilized ABS polymer with YI and artificial weathering Material used for tested specimem from example No. composition 0 h 234 h 495 h yellowness index (YI) I-1-3 .sup.b) 99.80% ABS .sup.c) 20.7 27.6 37.7 0.20% SM-13 I-1-4 .sup.a) 99.80% ABS 21.1 29.2 39.9 0.20% TA-1-7 delta E of yellowness index (YI) I-1-3 .sup.b) 99.80% ABS — 5.7 11.6 0.20% SM-13 I-1-4 .sup.a) 99.80% ABS — 4.7 11.0 0.20% TA-1-7 Footnotes: .sup.a) according to the invention .sup.b) comparative .sup.c) Terluran GP-22 from the company Styrolution

[0464] Table I-2 shows that the discoloration behavior measured via yellowness index and delta E of the inventive example versus the comparative example is in the same range.