3-PHENYL-BENZOFURAN-2-ONE DIPHOSPHITE DERIVATIVES AS STABILIZERS

Abstract

The invention relates to a composition comprising an organic material susceptible to oxidative, thermal or light-induced degradation and a compound of formula I-P, I-O or I-M. Further embodiments are a compound of formula I-P, I-O or I-M, a process for protection of the organic material by the compound, the use of the compound against degradation of the organic material, an additive composition comprising the compound, a process for manufacturing the compound and an intermediate involved therein.

##STR00001##

Claims

1: A composition, which comprises a) an organic material susceptible to oxidative, thermal or light-induced degradation, and b) a compound of formula I-P, I-O or I-M ##STR00033## wherein R.sup.1P represents one of the subformulae II-P, II-O or II-M ##STR00034## R.sup.1O represents one of the subformulae II-O or II-M, or R.sup.1M represents the subformula II-M; R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.P2, R.sup.P3, R.sup.P5 and R.sup.P6 are independently from each other hydrogen or C.sub.1-C.sub.3-alkyl, R.sup.O1, R.sup.O2, R.sup.O5 and R.sup.O6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, and R.sup.M1, R.sup.M3, R.sup.M5 and R.sup.M6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl.

2: The composition according to claim 1, wherein the organic material is a polymer, an oligohydroxy compound, a wax, a fat or a mineral oil.

3: The composition according to claim 2, wherein the organic material is a polymer, which is a polyolefin or a copolymer thereof, a polystyrene or a copolymer thereof, a polyurethane or a copolymer thereof, a polyether, which is obtained by the polymerization of an epoxide, an oxetane or a tetrahydrofuran, or a copolymer thereof, a polyester or a copolymer thereof, a polycarbonate or a copolymer thereof, a poly(vinyl chloride) or a copolymer thereof, a poly(vinylidene chloride) or a copolymer thereof, a polysulfone or a copolymer thereof, a poly(vinyl acetate) or a copolymer thereof, a poly(vinyl alcohol) or a copolymer thereof, a poly(vinyl acetal) or a copolymer thereof, or a polyamide or a copolymer thereof.

4: The composition according to claim 1, wherein R.sup.4 and R.sup.6 are hydrogen, R.sup.5 and R.sup.7 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.P2 and R.sup.P6 are independently from each other hydrogen or C.sub.1-alkyl, R.sup.P3 and R.sup.P5 are independently from each other hydrogen or C.sub.1-C.sub.4-alkyl, R.sup.O1 and R.sup.O6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.O2 is hydrogen or C.sub.1-alkyl, R.sup.O5 is hydrogen or C.sub.1-C.sub.4-alkyl, R.sup.M1 is hydrogen or C.sub.1-alkyl, R.sup.M3 and R.sup.M5 are independently from each other hydrogen or C.sub.1-C.sub.4-alkyl, and R.sup.M6 is hydrogen or C.sub.1-C.sub.8-alkyl.

5: The composition according to claim 1, wherein the compound is of formula I-P or I-O, R.sup.1P represents one of the subformulae II-P or II-O, and R.sup.1O represents the subformula II-O.

6: The composition according to claim 1, which comprises: a) a polymer, which is a polyolefine or a copolymer thereof or a polystyrene or a copolymer thereof, and b) the compound is of formula I-P or I-O, wherein R.sup.1P represents subformula II-P, R.sup.1O represents subformula II-O, R.sup.4 and R.sup.6 are hydrogen, R.sup.5 and R.sup.7 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.O1 is hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.O2, R.sup.O5 and R.sup.O6 are hydrogen, R.sup.P2 and R.sup.P6 are hydrogen, and R.sup.P3 and R.sup.P5 are independently from each other hydrogen or C.sub.1-C.sub.4-alkyl.

7: The composition according to claim 1, wherein component b) is contained in an amount of 0.0005% to 10% based on the weight of component a).

8: The composition according to claim 1, which further comprises, as component c), a further additive.

9: The composition according to claim 8, wherein component c) is a phosphite or phosphonite different to component b), an acid scavenger, a phenolic antioxidant or an aminic antioxidant.

10: The composition according to claim 9, wherein component c) is an ester of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid.

11: The composition according to claim 8, which further comprises, as component d), a second further additive, which is a phosphite or phosphonite different to component b), an acid scavenger, a phenolic antioxidant or an aminic antioxidant; with the proviso that component d) is a different compound than component c).

12: A process for protection of an organic material susceptible to oxidative, thermal or light-induced degradation, which comprises: incorporating into or applying onto an organic material a compound of formula I-P, I-O or I-M as defined in claim 1.

13: The process according to claim 12, wherein the organic material is a polymer, wherein said incorporating into the polymer takes place and a part or the complete incorporating takes place at a temperature between 135° C. to 350° C.

14. (canceled)

15: A compound of formula I-P, I-O or I-M ##STR00035## wherein R.sup.1P represents one of the subformulae II-P, II-O or II-M ##STR00036## R.sup.1O represents one of the subformulae II-O or II-M, or R.sup.1M represents the subformula II-M; R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.P2, R.sup.P3, R.sup.P5 and R.sup.P6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.O1, R.sup.O2, R.sup.O5 and R.sup.O6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, and R.sup.M1, R.sup.M3, R.sup.M5 and R.sup.M6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl.

16: An additive composition, which comprises: b) a compound of formula I-P, I-O or I-M as defined in claim 1, and c) a further additive, which is a phosphite or phosphonite different to component b), an acid scavenger, a phenolic antioxidant or an aminic antioxidant.

17: The additive composition according to claim 16, which comprises as component c) a phenolic antioxidant, which is an ester of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid.

18: The additive composition according to claim 16, which further comprises, as component d), a second further additive, which is a phosphite or phosphonite different to component b), an acid scavenger, a phenolic antioxidant or an aminic antioxidant; with the proviso that component d) is a different compound than component c).

19: An intermediate compound of formula IN-P, IN-O or IN-M ##STR00037## wherein Z.sup.1P-IN, Z.sup.1O-IN and Z.sup.1M-IN are independently from each other halogen, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.P2, R.sup.P3, R.sup.P5 and R.sup.P6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, R.sup.O1, R.sup.O2, R.sup.O5, and R.sup.O6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl, and R.sup.M1, R.sup.M3, R.sup.M5 and R.sup.M6 are independently from each other hydrogen or C.sub.1-C.sub.8-alkyl.

Description

SYNTHETIC EXAMPLES

[0165] The synthetic procedures are conducted under a nitrogen atmosphere.

[0166] If not otherwise stated, the starting materials are commercially available, for example from Aldrich Corp.

Example S-1: Synthesis of Compound (101)

[0167] ##STR00029##

5.0 g (15 mmol) of compound (201) (obtainable according to EP 2500341 A, page 8, example 1) are dissolved in 40 mL of dry dichloroethane at 65° C. To the solution are first added 1.41 g (18 mmol) of dry pyridine and then within 25 min 1.96 g (7 mmol) of compound (301) (3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, obtainable according to Lucas et al., Tetrahedron Lett. 2005, 46, 3347). The reaction mass is stirred under reflux for 3 h, cooled to room temperature and filtrated. After removal of solvent a glassy residue is obtained which is further dried at 70° C. under vacuum. 4.18 g (65% of theory) of compound (101) as a white glassy solid are obtained.

[0168] .sup.31P-NMR (toluene-d.sub.8): 116 ppm

[0169] .sup.1H-NMR (toluene-d.sub.8): 4.4 ppm (s, 2H, CH at lactone-ring)

[0170] MS (LC/MS, ACPI positive mode): [M+1].sup.+=870

Example S-2: Synthesis of Compound (102)

[0171] ##STR00030##

[0172] Compound (102) is prepared in analogy to example 1 from compound (202) (obtainable according to EP 2500341 A, page 8, example 1 by using the corresponding 4-tert-octylphenol) and obtained in a yield of 69% of theory as an amorphous solid.

[0173] .sup.31P-NMR (toluene-d.sub.8): 116 ppm

[0174] .sup.1H-NMR (toluene-d.sub.8): 4.3 ppm (s, 2H, CH at lactone-ring)

[0175] MS (LC/MS, ACPI positive mode): [M+1].sup.+=1094

Example S-3: Synthesis of Compound (103)

[0176] ##STR00031##

[0177] Compound (103) is prepared in analogy to example 1 from compound (203) (obtainable according to EP 0648765 A, page 30, compound 115) and obtained in a yield of 81% of theory as an amorphous solid.

[0178] .sup.31P-NMR (toluene-d.sub.8): 122 ppm

[0179] .sup.1H-NMR (toluene-d.sub.8): 4.3 ppm (s, 2H, CH at lactone-ring)

[0180] MS (LC/MS, ACPI positive mode): [M+1].sup.+=926

Example S-4: Synthesis of Compound (104)

[0181] ##STR00032##

[0182] Compound (104) is prepared in analogy to example 1 from compound (204) (obtainable according to WO 80/01566) and obtained in a yield of 87% of theory as an amorphous solid.

[0183] .sup.31P-NMR (toluene-d.sub.8): 123 ppm

[0184] .sup.1H-NMR (toluene-d.sub.8): 4.3 ppm (s, 2H, CH at lactone ring)

[0185] MS (LC/MS, ACPI positive mode): [M+1].sup.+=1010

Application Examples

[0186] The following known stabilizers are partly employed in addition to the inventive compounds:

AO-1 is Irganox 1010 (RTM BASF), which contains pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate).
AO-2 is Irganox 1076 (RTM BASF), which contains octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate.
Phos-1 is Irgafos 168 (RTM BASF), which contains tris(2,4-di-tert-butylphenyl) phosphite.
CaSt is commercially available calcium stearate, which acts as an acid scavenger.
ZnO is commercially available zinc oxide, which acts as an acid scavenger.

Example A-1: Stabilization of Polypropylene Homopolymer

[0187] The various additives are blended with Moplen HF 501 N (RTM LyondellBasell, polypropylene homopolymer, powder, melt flow rate 10 g/10 min (230° C./2.16 kg), which is essentially free of any additives, in a composition according to the table A-1. The blending is carried out using a Turbula mixer.

[0188] The thoroughly blended formulations are then melt compounded in a single screw extruder at lower temperature (200° C.) under nitrogen, which is denoted in the table A-1 as the zero pass extrusion. This ensures good melt mixing with minimal damage to the polymer due to oxidative degradation.

[0189] The resultant zero pass extrudate is then extruded multiple times with a single screw extruder at a higher temperature (280° C.) and open to air. Extrusion at higher temperatures, in combination with the presence of oxygen (air) enhances the rate of polymer degradation. These aggressive extrusion conditions put a strain on the stabilization system, which allows for differentiation. Pelletized samples of zero, first, third and fifth pass extrudate are collected and stored in sealed plastic bags at room temperature in storage boxes in the dark.

[0190] Melt Flow Rates: The samples are tested for retention of molecular mass (weight). This is measured by melt flow rate retention (according to ASTM-1238) on a Göttfert MPD02. The test conditions are 230° C. and 2.16 kg. Melt flow rates are measured in grams of polymer that flow out of a defined orifice in 10 minutes and are stated as grams/10 minutes (decigrams/minute). The results are depicted in table A-1.

TABLE-US-00001 TABLE A-1 composition No. 1 .sup.a) 2 .sup.a) 3 .sup.b) 4 .sup.b) 5 .sup.b) Moplen HF 501 N 99.879 99.825 99.868 99.868 99.868 CaSt 0.050 0.050 0.050 0.050 0.050 AO-1 0.050 0.050 0.050 0.050 0.050 Phos-1 0.021 0.075 0.021 0.021 0.021 compound (101) — — 0.011 — — compound (102) — — — 0.011 — compound (104) — — — — 0.011 total additives content 0.121 0.175 0.132 0.132 0.132 280° C. melt processing melt flow rates zero pass 9.6 9.3 8.5 9.8 9.0 1.sup.st pass 16.6 13.2 10.6 11.3 11.0 3.sup.rd pass 33.3 22.7 14.1 15.3 15.0 5.sup.th pass 58.0 42.6 17.8 22.2 22.2 Footnotes: .sup.a) reference; .sup.b) inventive

[0191] The compositions comprised of a low concentration of an inventive compound (110 ppm), a phenolic antioxidant (500 ppm) and a traditional phosphite melt processing stabilizer (210 ppm) provide good performance as measured by retention of melt flow rates in comparison to a common binary blend of the phenolic antioxidant (500 ppm) and the traditional phosphite melt processing stabilizer (210 or 750 ppm). The ternary blend comprising an inventive compound provides as good or better performance at lower concentrations (820 ppm) in comparison to the common binary blends at higher concentrations (1250 ppm).

Examples A-2-1 to A-2-4

Polymer Processing Experimental

[0192] The various additives are blended with the stated applied granular polymer, which is essentially free of any stabilization additives, in a composition according to the respective tables A-2-1 to A-2-4. The blending is carried out using a Henschel, a Turbula or a Kitchen-Aid mixer.

[0193] The thoroughly blended formulations are melt compounded in a twin screw extruder at a lower temperature of 210° C. (410° F.) under nitrogen, which is denoted in the tables as the zero pass extrusion. This ensures good melt mixing with minimal damage to the polymer due to oxidative degradation.

[0194] The resultant zero pass extrudate is then extruded multiple times with a single screw extruder, fitted with a Maddock mixing section, at a higher temperature of 260° C. (500° F.) or 280° C. (535° F.), open to air. Extrusion at higher temperatures in combination with the presence of oxygen (air) enhances the rate of polymer degradation. Pelletized samples of zero, first, third and fifth pass extrudate are collected and stored in sealed plastic bags at room temperature in storage boxes in the dark.

[0195] Melt Flow Rates: The samples are tested for retention of molecular mass (weight). This is measured by melt flow rate retention according to ASTM-1238 on a Tinius-Olsen Extrusion Plastometer. For polypropylene type polymer samples, the test conditions are 230° C. and 2.16 kg. For polyethylene type polymer samples, the test conditions are 190° C. and 2.16 kg or 21.6 kg. The melt flow ratio is calculated as the melt flow rate at 21.6 kg divided by the melt flow rate at 2.16 kg. Melt flow rates are measured in grams of polymer that flow out of a defined orifice in 10 minutes and are stated as grams/10 minutes (decigrams per minute).

[0196] Oven Aging: Some samples are tested for oxidative stability below the melting point of the polymer using oven aging to accelerate polymer degradation. This is done by put-ting compression molded plaques of 1 mm (40 mils) in a Blue M forced draft oven equipped with a rotating carousel in order to homogenize the exposure to an elevated temperature of 135° C. or 150° C. inside the oven. Failure is measured by days to embrittlement by bending the plaque every 3 to 4 days until the plaque snapped due to oxidative degradation. The time is stated in days.

[0197] Oxidative Induction Time: Some samples are tested for oxidative stability above the melting point of the polymer using oxidative induction time (OIT) as a means of measuring the activity of the stabilizer in the polymer melt at a high temperature of 190° C. in an oxidative environment (oxygen). The experiments are run on a differential scanning calorimeter (DSC). Scans are collected using a heating rate of 10° C./min under nitrogen from 50° C. to 190° C., then switching to oxygen and holding at isothermal conditions until catastrophic oxidation. Time to onset of catastrophic oxidation (observed as a strong exotherm) is stated in minutes.

Example A-2-1: Stabilization of Molding Grade Ziegler-Natta Polypropylene Homopolymer

[0198] A molding grade Ziegler-Natta polypropylene homopolymer (zn-PP-homopolymer) with a melt flow rate of 4 dg/min from a bulk/slurry phase polymerization process is evaluated.

TABLE-US-00002 TABLE A-2-1 composition No. 1 .sup.a) 2 .sup.a) 3 .sup.a) 4 .sup.b) zn-PP-homopolymer 99.890 99.840 99.790 99.8575 CaSt 0.060 0.060 0.060 0.060 AO-1 0.050 0.050 0.050 0.050 Phos-1 — 0.050 0.100 0.022 compound (103) — — — 0.0105 total additives content 0.110 0.160 0.210 0.1425 260° C. (500° F.) melt processing melt flow rates zero pass 6.03 4.59 3.90 4.17 1.sup.st pass 9.78 6.05 4.38 4.48 3.sup.rd pass 13.85 7.20 5.41 5.15 5.sup.th pass 17.27 9.91 6.32 5.45 oven ageing at 135° C. zero pass 52 58 62 62 oven ageing at 150° C. zero pass 4 6 6 6 280° C. (535° F.) melt processing melt flow rates zero pass 6.03 4.59 3.90 4.17 1.sup.st pass 12.03 7.04 5.19 4.22 3.sup.rd pass 21.84 10.49 6.81 5.35 5.sup.th pass 34.35 17.07 9.13 6.45 Footnotes: .sup.a) reference; .sup.b) inventive

[0199] The composition comprised of a low concentration of compound (103) (105 ppm), a phenolic antioxidant (500 ppm) and a traditional phosphite melt processing stabilizer (220 ppm) provides good performance as measured by retention of melt flow rates in comparison to a common binary blend of the phenolic antioxidant (500 ppm) and the traditional phosphite melt processing stabilizer (500 or 1000 ppm). The ternary blend comprising an inventive compound provides as good or better performance at lower concentrations (825 ppm) in comparison to the common binary blends at higher concentrations (1000 or 1500 ppm). There are no deleterious effects to the long term thermal stability provided by the phenolic antioxidant observed when measured by oven aging at 135° C. or 150° C.

Example A-2-2: Stabilization of Molding Grade Ziegler-Natta Polypropylene Copolymer

[0200] A molding grade Ziegler-Natta polypropylene copolymer (zn-PP-copolymer; ethylene as comonomer in around 2% by weight) with a melt flow rate of 3 dg/min from a bulk/slurry phase polymerization process is evaluated.

TABLE-US-00003 TABLE A-2-2 composition No. 1 .sup.a) 2 .sup.a) 3 .sup.a) 4 .sup.b) zn-PP-homopolymer 99.890 99.840 99.790 99.8575 CaSt 0.060 0.060 0.060 0.060 AO-1 0.050 0.050 0.050 0.050 Phos-1 — 0.050 0.100 0.022 compound (103) — — — 0.0105 total additives content 0.110 0.160 0.210 0.1425 260° C. (500° F.) melt processing melt flow rates zero pass 4.60 3.34 2.79 3.04 1.sup.st pass 7.98 4.64 3.34 3.21 3.sup.rd pass 11.47 5.72 3.99 3.92 5.sup.th pass 16.03 7.49 4.89 4.59 oven ageing at 135° C. zero pass 23 42 56 56 oven ageing at 150° C. zero pass 2 3 3 3 280° C. (535° F.) melt processing melt flow rates zero pass 4.60 3.34 2.79 3.04 1.sup.st pass 10.50 5.11 3.68 3.72 3.sup.rd pass 20.24 9.81 5.89 4.43 5.sup.th pass 32.38 15.02 8.45 6.88 Footnotes: .sup.a) reference; .sup.b) inventive

[0201] The composition comprised of a low concentration of compound (103) (105 ppm), a phenolic antioxidant (500 ppm) and a traditional phosphite melt processing stabilizer (220 ppm) provides good performance as measured by retention of melt flow rates in comparison to a common binary blend of the phenolic antioxidant (500 ppm) and the traditional phosphite melt processing stabilizer (500 or 1000 ppm). The ternary blend comprising an inventive compound provides nearly as good or better performance at lower concentrations (825 ppm) in comparison to the common binary blends at higher concentrations (1000 or 1500 ppm). There are no deleterious effects to the long term thermal stability provided by the phenolic antioxidant observed when measured by oven aging at 135° C. or 150° C.

Example A-2-3: Stabilization of Film Grade Ziegler-Natta Linear Low Density Polyethylene Copolymer

[0202] A film grade Ziegler-Natta polyethylene copolymer (zn-LLDPE-copolymer; butene as comonomer, density 0.92 g/cm.sup.3) with a melt flow rate of 2 dg/min at 190° C. and 2.16 kg from a gas phase polymerization process is evaluated.

TABLE-US-00004 TABLE A-2-3 composition No. 1 .sup.a) 2 .sup.a) 3 .sup.a) 4 .sup.b) zn-LLDPE-copolymer 99.935 99.915 99.845 99.925 ZnO 0.015 0.015 0.015 0.015 AO-2 0.020 0.020 0.020 0.020 Phos-1 0.030 0.050 0.130 0.030 compound (103) — — — 0.010 total additives content 0.065 0.085 0.155 0.075 260° C. (500° F.) melt processing melt flow rates (190° C./2.16 kg) zero pass 2.17 2.12 2.15 2.12 1.sup.st pass 1.81 1.90 2.01 1.97 3.sup.rd pass 1.46 1.60 1.89 1.76 5.sup.th pass 1.24 1.36 1.64 1.58 melt flow rates (190° C./21.6 kg) zero pass 54.12 53.48 54.51 53.17 1.sup.st pass 51.85 52.43 51.55 52.43 3.sup.rd pass 49.34 50.27 50.63 51.21 5.sup.th pass 47.53 47.99 46.47 49.81 melt flow ratio (190° C.; 21.6 kg/2.16 kg) zero pass 24.93 25.27 25.37 25.07 1.sup.st pass 28.62 27.65 25.68 26.58 3.sup.rd pass 33.75 31.48 26.86 29.04 5.sup.th pass 38.23 35.31 28.30 31.56 oxidative induction time (10 mil films/onset at 190° C.) zero pass 26 39 74 45 Footnotes: .sup.a) reference; .sup.b) inventive

[0203] The composition comprised of a low concentration of compound (103) (100 ppm), in combination with a phenolic antioxidant (200 ppm) and common phosphite melt processing stabilizer (300 ppm), provides good performance as measured by retention of melt flow rates in comparison to a traditional binary blend of the phenolic antioxidant (200 ppm) and the common phosphite melt processing stabilizer (500 or 1300 ppm). The ternary blend provides as good or better performance at lower concentrations (600 ppm) in comparison to the common binary blends at higher concentrations (700-1300 ppm). No deleterious effect to the oxidative stability provided by the phenolic antioxidant is observed as measured by oxidative induction time.

Example A-2-4: Stabilization of Molding Grade Cr Based High Density Polyethylene

[0204] A molding grade chromium catalyzed polyethylene (Cr-HDPE; density 0.955 g/cm.sup.3) with a melt flow rate of 0.3 dg/min at 190° C. and 2.16 kg from a gas phase polymerization process is evaluated.

TABLE-US-00005 TABLE A-2-4 composition No. 1 .sup.a) 2 .sup.a) 3 .sup.a) 4 .sup.b) Cr-HDPE 99.935 99.915 99.845 99.925 AO-1 0.050 0.050 0.050 0.050 Phos-1 — 0.050 0.100 0.022 compound (103) — — — 0.011 total additives content 0.050 0.100 0.150 0.083 260° C. (500° F.) melt processing melt flow rates (190° C./2.16 kg) zero pass 0.22 0.28 0.29 0.32 1.sup.st pass 0.20 0.26 0.29 0.29 3.sup.rd pass 0.18 0.25 0.25 0.28 5.sup.th pass 0.13 0.17 0.21 0.26 melt flow rates (190° C./21 .6 kg) zero pass 26.73 28.27 28.43 29.08 1.sup.st pass 28.37 29.35 29.89 31.50 3.sup.rd pass 28.74 28.39 29.59 32.04 5.sup.th pass 26.77 27.82 29.06 31.86 melt flow ratio (190° C.; 21.6 kg/2.16 kg) zero pass 121.72 100.03 99.37 91.61 1.sup.st pass 140.00 112.18 104.62 107.83 3.sup.rd pass 162.47 134.80 120.51 116.30 5.sup.th pass 200.50 165.00 138.98 120.27 oxidative induction time (10 mil films/onset at 190° C.) zero pass 68 106 151 110 Footnotes: .sup.a) reference; .sup.b) inventive

[0205] The composition comprised of a low concentration of compound (103) (110 ppm) in combination with a phenolic antioxidant (500 ppm) and a common phosphite melt processing stabilizer (220 ppm) provides good performance as measured by retention of melt flow rates in comparison to a common binary blend of the phenolic antioxidant (500 ppm) and the common phosphite melt processing stabilizer (500 or 1000 ppm). The ternary blend provides nearly as good or better performance at lower concentrations (830 ppm) in comparison to the common binary blends at higher concentrations (1000-1500 ppm). No deleterious effect to the oxidative stability provided by the phenolic antioxidant is observed as measured by oxidative induction time.