Propylene copolymer compositions

• US 20070078203A1
• Filed: 09/25/2006
• Published: 04/05/2007
• Est. Priority Date: 10/04/2005
• Status: Abandoned Application

• Current Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Gohill, Bharatkumar
• Application Number:
  US11/526,434
• Publication Number:
  US 20070078203A1
• Time in Patent Office: Days
• US Class Current: 524/117
• CPC Class Codes: C07F 9/65744 condensed with carbocyclic or heterocyclic rings or ring systems
• CPC Class Codes: C08K 5/005 Stabilisers against oxidation, heat, light, ozone
• CPC Class Codes: C08K 5/0083 Nucleating agents promoting the crystallisation of the polymer matrix
• CPC Class Codes: C08K 5/0091 Complexes with metal-heteroatom-bonds
• CPC Class Codes: C08K 5/098 Metal salts of carboxylic acids
• CPC Class Codes: C08K 5/5313 Phosphinic compounds, e.g. R2=P(:O)OR'
• CPC Class Codes: C08L 23/142 at least partially crystalline copolymers of propene with other olefins
• CPC Class Codes: C08L 2314/02 Ziegler natta catalyst
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials

Abstract

Gamma irradiation resistant propylene/ethylene copolymer compositions are provided comprising: i) a propylene/ethylene copolymer comprising from about 2 to about 3.5 wt. % ethylene; ii) from about 800 ppm to about 1200 ppm of one or more light stabilizers; iii) from about 300 ppm to about 1200 ppm of one or more acid scavengers; iv) from about 1600 ppm to about 2200 ppm of aluminum, hydroxybis[2,4,8,10 tetrakis (1,1-dimethyl(ethyl)-6-hydroxy-12H dibenzo[d,g][1,3,2] dioxaphoshocin 6-oxidato]; and v) a sufficient amount of one of more viscosity modifiers to break down the resulting polymer viscosity to a melt index from about 23 to about 31 g/10 minutes measured at about 230° C./2160 g.

Claims

1. Gamma irradiation resistant propylene/ethylene copolymer compositions comprising:

i) a propylene/ethylene copolymer comprising from about 2 to about 3.5 wt. % ethylene;

ii) from about 800 ppm to about 1200 ppm of one or more light stabilizers;

iii) from about 300 ppm to about 1200 ppm of one or more acid scavengers;

iv) from about 1600 ppm to about 2200 ppm of aluminum, hydroxybis[2,4,8,10 tetrakis (1,1-dimethyl(ethyl)-6-hydroxy-12H dibenzo[d,g][1,3,2] dioxaphoshocin 6-oxidato]; and

v) a sufficient amount of one or more viscosity modifiers to break down the resulting polymer viscosity to a melt index from about 23 to about 31 g/10 minutes measured at about 230°

C./2160 g.

2. Propylene/ethylene copolymer compositions according to claim 1, wherein the ethylene content ranges from about 2.6 to about 3.2 wt % ethylene.

3. Propylene/ethylene copolymer compositions according to claim 1, wherein the copolymer is a random copolymer produced in the presence of a Ziegler-Natta catalyst.

4. Propylene/ethylene copolymer compositions according to claim 1 initially exhibiting a melt index of less than about 3 g/10 minutes measured at 230°

C./2160 g.

5. Propylene/ethylene copolymer compositions according to claim 1, wherein the molecular weight distribution of the copolymer is less than about 5.5±

10%.

6. Propylene/ethylene copolymer compositions according to claim 1, wherein the light stabilizer comprises one or more polymeric hindered amines.

7. Propylene/ethylene copolymer compositions according to claim 6, wherein the light stabilizer comprises 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]].

8. Propylene/ethylene copolymer compositions according to claim 6, wherein the light stabilizer comprises a combination of dimethyl succinate and tetramethyl hydroxy-1-hydroxyethyl piperidine polymer.

9. Propylene/ethylene copolymer compositions according to claim 6, wherein the light stabilizer comprises oxidized bis (hydrogenated tallow alkyl) amine and 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]] at a 1:

1 ratio.

10. Propylene/ethylene copolymer compositions according to claim 6, wherein the light stabilizer comprises poly [[6-[(1,1,3,3-tetramethyl/butyl)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]], dimethyl succinate, and tetramethyl hydroxy-1-hydroxyethyl piperidine polymer.

11. Propylene/ethylene copolymer compositions according to claim 1, wherein the acid scavenger comprises calcium stearate.

12. Propylene/ethylene copolymer compositions according to claim 11, wherein the calcium stearate content ranges from about 800 ppm to about 1200 ppm.

13. Propylene/ethylene copolymer compositions according to claim 1, wherein the acid scavenger comprises synthetic hydrotalcite.

14. Propylene/ethylene copolymer compositions according to claim 13, wherein the synthetic hydrotalcite content ranges from about 300 ppm to about 500 ppm.

15. Propylene/ethylene copolymer compositions according to claim 1, wherein the viscosity modifier comprises (2,5-dimethyl 2,5-di(tert-butyl peroxy) hexane.

16. Propylene/ethylene copolymer compositions according to claim 1, wherein the aluminum, hydroxybis[2,4,8,10 tetrakis (1,1-dimethyl(ethyl)-6-hydroxy-12H dibenzo[d,g][1,3,2] dioxaphoshocin 6-oxidato], content ranges from about 1800 ppm to about 2000 ppm.

23. A syringe assembly comprising a syringe barrel and a syringe plunger adapted to travel within said barrel, wherein said barrel and optionally said plunger are fabricated from the propylene/ethylene copolymer composition of claim 1.

17. Propylene/ethylene copolymer compositions comprising:

i) a propylene/ethylene copolymer comprising from about 2 to about 3.5 wt. % ethylene;

ii) from about 800 ppm to about 1200 ppm calcium stearate;

iii) from about 800 ppm to about 1200 ppm of a combination of dimethyl succinate and tetramethyl hydroxy-1-hydroxyethyl piperidine polymer;

iv) from about 800 ppm to about 1200 ppm of 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]];

v) from about 1600 ppm to about 2200 pm of aluminum, hydroxybis [2,4,8,10 tetrakis (1,1-dimethyl(ethyl)-6-hydroxy-12H dibenzo [d,g][1,3,2] dioxaphoshocin 6-oxidato]; and

vi) a sufficient amount of (2,5-dimethyl 2,5-di(tert-butyl peroxy) hexane to break down the resulting polymer viscosity to a melt index from about 23 to about 31 g/10 minutes measured at 230°

C./2160 g.

18. Propylene/ethylene copolymer compositions according to claim 17 wherein the propylene/ethylene copolymer is a Ziegler-Natta catalyst polymerized random copolymer comprising from about 2.6 to about 3.2 wt % ethylene.

19. Propylene/ethylene copolymer compositions according to claim 18 wherein the initial melt index is less than about 3 g/10 minutes measured at 230°

C./2160 g, and the molecular weight distribution of the copolymer is less than about 5.5±

10%.

24. A syringe assembly comprising a syringe barrel and a syringe plunger adapted to travel within said barrel, wherein said barrel and optionally said plunger are fabricated from the propylene/ethylene copolymer composition of claim 17.

20. Propylene/ethylene copolymer compositions comprising:

i) a propylene/ethylene copolymer comprising from about 2 to about 3.5 wt. % ethylene;

ii) from about 300 ppm to about 500 ppm synthetic hydrotalcite;

iii) from about 800 ppm to about 1200 ppm oxidized bis (hydrogenated tallow alkyl) amine and 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]] at a 1;

1 ratio;

iv) from about 1600 ppm to about 2200 ppm of aluminum, hydroxybis[2,4,8,10 tetrakis (1,1-dimethyl(ethyl)-6-hydroxy-12H dibenzo[d,g][1,3,2] dioxaphoshocin 6-oxidato]; and

v) a sufficient amount of (2,5-dimethyl 2,5-di(tert-butyl peroxy) hexane to break down the resulting polymer viscosity to a melt index from about 23 to about 31 g/10 minutes measured at 230°

C./2160 g.

21. Propylene/ethylene copolymer compositions according to claim 20 wherein the propylene/ethylene copolymer is a Ziegler-Natta catalyst polymerized random copolymer comprising from about 2.6 to about 3.2 wt % ethylene.

22. Propylene/ethylene copolymer compositions according to claim 21 wherein the initial melt index is less than about 3 g/10 minutes measured at 230°

C./2160 g, and the molecular weight distribution of the copolymer is less than about 5.5±

10%.

25. A syringe assembly comprising a syringe barrel and a syringe plunger adapted to travel within said barrel, wherein said barrel and optionally said plunger are fabricated from the propylene/ethylene copolymer composition of claim 20.