Antistatic system for polymers

1. A shaped polymer article having improved surface resistivity comprising a major proportion of a thermoplastic polymer and a minor proportion of an antistatic system, wherein the antistatic system comprises an inorganic oxide having a surface treatment comprising (a) an ethoxylated alkylamine defined by the formula:

R 1 N—(CH 2 CH 2 OH) 2

wherein R 1 is a C 8 to C 30 alkyl radical and

(b) a polyoxyalkylene siloxane defined by the formula:

(R 2 ) 3 SiOSi(R 2 )(R 3 )OSi(R 2 ) 3

wherein

each R 2 is independently H, CH 3 or C 2 H 5 ;

R 3 is a polyoxyalkylene group having the following formula:

—C n H 2n OZR 4

wherein

Z is [ethylene oxide] a [propylene oxide] b in block or random order;

n is independently an integer of 2 to 8;

a is an integer of 0 to about 20; b is an integer of 0 to about 30; provided that a+b is from 1 to about 50;

R 4 is independently H, OH, OCH 3 , acetyl, or a linear or branched alkyl or aryl group having 1 to about 20 carbon atoms.

2. The shaped polymer article of claim 1 wherein R 1 contains 13 to 15 carbon atoms.

3. The shaped polymer article of claim 1 wherein R 2 is H or CH 3 and R 4 is hydrogen or CH 3 .

4. The shaped polymer article of claim 1 wherein R 2 is CH 3 and R 4 is hydrogen.

5. The shaped polymer article of claim 1 wherein the inorganic oxide is titanium dioxide.

6. The shaped polymer article of claim 1 in which the polyoxyalkylene siloxane is a polyoxyethylene trisiloxane.

7. The shaped polymer article of claim 1 wherein the thermoplastic polymer is selected from the group consisting of a polymer of an ethylenically unsaturated monomer; polyvinyl; polyvinyl ester; polystyrene; acrylic homopolymer and copolymer; phenolic; alkyd; amino resin; epoxy resin; amide; urethane; phenoxy resin; sulfone; carbonate; ester and chlorinated ester; ether; acetal resin; imide; and oxyethylene.

8. The shaped polymer article of claim 7 wherein the polymer of an ethylenically unsaturated monomer is a polyolefin.

9. The shaped polymer article of claim 7 wherein the polyolefin is selected from the group consisting of polyethylene, polypropylene, polybutylene, and copolymer of ethylene with a higher olefin or polyvinyl acetate.

10. The shaped polymer article of claim 1 wherein the polymer article is a film.

11. The shaped polymer article of claim 10 wherein the film has a surface resistivity of about 10E 10 to about 10E 13 ohms.

12. The shaped polymer article of claim 1 wherein the proportion of the thermoplastic polymer ranges from 80 wt. % to about 99.99 wt. % and the proportion of the treated pigment ranges from about 0.01 wt. % to about 20 wt. % based on the entire weight of the shaped polymer article.

13. The shaped polymer article of claim 1 wherein the antistatic system is made by a process comprising:

(i) metering the siloxane, the polyethoxylated alkylamine or a mixture thereof into a flow restrictor, having an inlet and an outlet, a motive gas, to create a zone of turbulence at the outlet of the flow restrictor thereby atomizing the siloxane, the polyethoxylated alkylamine or a mixture thereof to form an atomized liquid; and

(ii) contacting an inorganic pigment with the atomized liquid to form an antistatic agent with the atomized liquid.

14. A shaped polymer article having a low surface resistivity comprising a major proportion of a thermoplastic polymer and a minor proportion of an antistatic system, wherein the antistatic system comprises an inorganic oxide having a surface treatment comprising (a) an ethoxylated alkylamine defined by the formula:

R 1 N—(CH 2 CH 2 OH) 2

wherein R 1 is a C 8 to C 30 alkyl radical and

(b) a reaction product of a siloxane having the structure:

and the oxirane monomers:

15. The shaped polymer article of claim 14 wherein the thermoplastic polymer is selected from the group consisting of a polymer of an ethylenically unsaturated monomer; polyvinyl; polyvinyl ester; polystyrene; acrylic homopolymer and copolymer; phenolic; alkyd; amino resin; epoxy resin; amide; urethane; phenoxy resin; sulfone; carbonate; ester and chlorinated ester; ether; acetal resin; imide; and oxyethylene.

16. The shaped polymer article of claim 14 wherein the polymer of an ethylenically unsaturated monomer is a polyolefin.

17. The shaped polymer article of claim 16 wherein the polyolefin is selected from the group consisting of polyethylene, polypropylene, polybutylene, and copolymer of ethylene with a higher olefin or polyvinyl acetate.

18. The shaped polymer article of claim 14 wherein the polymer article is a film.

19. The shaped polymer article of claim 18 wherein the film has a surface resistivity of about 10E 10 to about 10E 13 ohms.

20. The shaped polymer article of claim 14 wherein the proportion of the thermoplastic polymer ranges from 80 wt. % to about 99.99 wt. % and the proportion of the surface treated inorganic oxide ranges from about 0.01 wt. % to about 20 wt. % based on the entire weight of the shaped polymer article.