Liquid Crystalline Polymer Composition for High Voltage Electronic Components

• US 20130123420A1
• Filed: 11/13/2012
• Published: 05/16/2013
• Est. Priority Date: 11/15/2011
• Status: Abandoned Application

• Current Assignee: Ticona LLC (Celanese Corporation)
• Original Assignee: Ticona LLC (Celanese Corporation)
• Inventors: Kim, Young Shin
• Application Number:
  US13/674,972
• Publication Number:
  US 20130123420A1
• Time in Patent Office: Days
• US Class Current: 524/592
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08K 5/0008 Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
• CPC Class Codes: C08K 5/13 Phenols; Phenolates
• CPC Class Codes: C08L 61/02 Condensation polymers of aldehydes or ketones only
• CPC Class Codes: C08L 67/03 the dicarboxylic acids and dihydroxy compounds having the carboxyl- and the hydroxy groups directly linked to aromatic rings
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: C08L 71/08 Polyethers derived from hydroxy compounds or from their metallic derivatives C08L71/02 takes precedence
• CPC Class Codes: C08L 77/00 Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08; Compositions of derivatives of such polymers
• CPC Class Codes: C09K 19/3809 Polyesters; Polyester derivatives, e.g. polyamides

Abstract

A liquid crystalline polymer composition having a relatively high comparative tracking index (“CTI”) is provided. The present inventors have discovered that high CTI values can be achieved through the use of inorganic particles in combination with a functional aromatic compound. While not fully understood, it is believed that the functional compound can react with the liquid crystalline polymer and create smaller degraded polymer chains. In combination with the inorganic particles, these smaller chains can potentially form insulated regions at the surface of the polymer that hinder the formation of conductive carbonaceous deposits during the tracking process, which could otherwise lead to failure during testing.

Claims

1. A polymer composition that comprises from about 20 wt. % to about 90 wt. % of at least one thermotropic liquid crystalline polymer, from about 1 wt. % to about 60 wt. % of inorganic particles, and from about 0.001 wt. % to about 5 wt. % of at least one functional aromatic compound having the general structure provided below in Formula (I):

2. The polymer composition of claim 1, wherein the functional aromatic compound includes a phenolic compound, diphenolic compound, naphthenic compound, or a combination thereof.

3. The polymer composition of claim 1, wherein the functional aromatic compound includes an aromatic diol.

4. The polymer composition of claim 3, wherein the aromatic diol is 4,4′

-biphenol.

5. The polymer composition of claim 1, wherein the functional aromatic compound includes an aromatic carboxylic acid.

6. The polymer composition of claim 1, wherein the aromatic carboxylic acid is 2,6-naphthelene dicarboxylic acid.

7. The polymer composition of claim 1, wherein the composition includes from about 0.01 wt. % to about 1 wt. % of at least one aromatic dial and from about 0.001 wt. % to about 0.5 wt. % of at least one aromatic dicarboxylic acid.

8. The polymer composition of claim 1, wherein the composition further includes at least one non-aromatic functional compound.

9. The polymer composition of claim 8, wherein the non-aromatic functional compound is a hydrate.

10. The polymer composition of claim 1, wherein the inorganic particles include titanium dioxide.

11. The polymer composition of claim 1, wherein the composition has a comparative tracking index of about 275 volts or more.

12. The polymer composition of claim 1, wherein functional aromatic compounds constitute from about 0.05 wt. % to about 0.5 wt. % of the composition, inorganic particles constitute from about 15 wt. % to about 50 wt. % of the composition, and liquid crystalline polymers constitute from about 40 wt. % to about 70 wt. % of the composition.

13. The polymer composition of claim 1, wherein the composition has a melt viscosity of from about 0.1 to about 80 Pa-s, as determined in accordance with ISO Test No. 11443 at a shear rate of 1000 seconds⁻

1 and temperature that is 15°

C. above the melting temperature of the composition.

14. The polymer composition of claim 1, wherein the polymer contains monomer units derived from 4-hydroxybenzoic acid, terephthalic acid, hydroquinone, 4,4′

-biphenol, acetaminophen, 6-hydroxy-2-naphthoic acid, 2,6-naphthelene dicarboxylic acid, or a combination thereof.

15. The polymer composition of claim 1, wherein the composition further comprises a mineral filler.

16. The polymer composition of claim 1, wherein the composition further comprises glass fibers.

17. A molded part comprising the polymer composition of claim 1.

18. An electronic component that comprises a polymer composition, wherein the polymer composition comprises at least one thermotropic liquid crystalline polymer, inorganic particles, and at least one functional aromatic compound having the general structure provided below in Formula (I):

19. The electronic component of claim 18, wherein the functional aromatic compound includes an aromatic diol.

20. The electronic component of claim 19, wherein the aromatic diol is 4,4′

-biphenol.

21. The electronic component of claim 18, wherein the functional aromatic compound includes an aromatic carboxylic acid.

22. The electronic component of claim 18, wherein the aromatic carboxylic acid is 2,6-naphthelene dicarboxylic acid.

23. The electronic component of claim 18, wherein the composition includes from about 0.01 wt. % to about 1 wt. % of at least one aromatic diol and from about 0.001 wt. % to about 0.5 wt. % of at least one aromatic dicarboxylic acid.

24. The electronic component of claim 18, wherein the composition further includes at least one non-aromatic functional compound.

25. The electronic component of claim 18, wherein the inorganic particles include titanium dioxide.

26. The electronic component of claim 18, wherein the composition has a comparative tracking index of about 275 volts or more.

27. The electronic component of claim 18, wherein liquid crystalline polymers constitute from about 20 wt. % to about 90 wt. % of the composition, inorganic particles constitute from about 1 wt. % to about 60 wt. % of the composition, and functional aromatic compounds constitute from about 0.001 wt. % to about 5 wt. % of the composition.

28. The electronic component of claim 18, wherein the composition has a melt viscosity of from about 0.1 to about 80 Pa-s, as determined in accordance with ISO Test No. 11443 at a shear rate of 1000 seconds⁻

1 and temperature that is 15°

C. above the melting temperature of the composition.

29. The electronic component of claim 18, wherein the composition further comprises a mineral filler.

30. The electronic component of claim 18, wherein the composition further comprises glass fibers.

31. The electronic component of claim 18, wherein the component is an electrical connector that comprises opposing walls between which a passageway is defined for receiving a contact pin, wherein at least one of the walls contains the polymer composition.

32. The electronic component of claim 18, wherein the electronic component is a cellular telephone, laptop computer, small portable computer, wrist-watch device, pendant device, headphone or earpiece device, media player with wireless communications capabilities, handheld computer, remote controller, global positioning system, handheld gaming device, battery cover, speaker, integrated circuit, electrical connector, camera module, housing, electrical control, circuit breaker, switch, power electronics, printer part, or a combination thereof.