Liquid crystalline polymer composition

• US 6,492,463 B1
• Filed: 07/07/1998
• Issued: 12/10/2002
• Est. Priority Date: 08/31/1994
• Status: Expired due to Term

• Current Assignee: Ticona LLC (Celanese Corporation)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Waggoner, Marion Glen
• Primary Examiner(s): Short, Patricia A.
• Application Number:
  US09/111,009
• Time in Patent Office: 1,617 Days
• Field of Search: 525/132, 525/426, 525/445, 525/450, 524/513, 524/514, 524/275, 524/277, 524/279
• US Class Current: 525/132
• CPC Class Codes: C08L 23/00 Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C08L 2666/06 Homopolymers or copolymers of unsaturated hydrocarbons; Derivatives thereof
• CPC Class Codes: C08L 67/00 Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain of polyester-amides C08L77/12; of polyester-imides C08L79/08; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: C08L 77/12 Polyester-amides
• CPC Class Codes: C08L 79/08 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors

Abstract

A composition comprising a thermotropic liquid crystalline polymer (LCP) and small quantities of low molecular weight polyethylene (PE) is disclosed. The PP acts as an internal lubricant or mold release, but suprisingly does not significantly increase the flammability of the LCP.

Claims

1. A composition comprising:

(a) a thermotropic aromatic liquid crystalline polymer; and

(b) from 0.05 to 2.5 percent by weight of said aromatic liquid crystalline polymer of polyethylene. said polyethylene having a molecular weight within the range between 1,000 to 10,000; and

(c) optionally additional components including fillers, pigments and antioxidants,

wherein said composition, noth with and without said polyethylene, has a flammability rating of V-O under the test conditions of UL-94 at a bar thickness of 0.079 mm (1/32 inch).

2. The composition of claim 1, wherein said polyethylene has a molecular weight within the range between 1,500 to 4,000.

3. The composition of claim 1, wherein said polyethylene is polar.

4. The composition of claim 3, wherein said polyethylene is made by low pressure polymerization.

5. The composition of claim 4, wherein said polyethylene is about 0.2 to 1.0 percent by weight of said aromatic liquid crystalline polymer.

6. The composition of claim 5, wherein said aromatic liquid crystalline polymers contains repeat units derived from one or more of 4-hydroxybenzoic acid, 6- hydroxynapthoic acid, terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 4,4′

-bibenzoic acid, hydroquinone, chlorohydroquinone, methylhydroquinone, t-butylhydroquinone, phenylhydroquinone, phenethylhydroquinone, 4,4-biphenol, resorcinol, or 2,6-dihydroxynaphthalene.

7. The composition of claim 5, wherein said aromatic liquid crystalline polymer consists essentially of the repeat units:

wherein the molar ratio of (I);

(II) ranges from 0;

100 to 100.0, wherein the molar ratio of (III);

(IV) ranges from 85.15 to 15.85, wherein the molar ratio of the total (I) and (II) to the total of (III) and (IV) is substantially 1;

1, and further wherein there are 100 to 600 moles of (V) per 100 moles of (I) plus (II).

8. The composition of claim 5, wherein said aromatic liquid crystalline polymer consists essentially of the repeat units:

wherein the molar ratio of (VI);

(VII) ranges from 0;

100 to 100.0, wherein the molar ratio of (VIII);

(IX) ranges from 25.75 to 90.10, the molar ratio of the sum of (VI) and (VII) to the sum of (VIII) and (IX) is substantially 1;

1, the molar ratio of (X);

(XI) ranges from 97;

3 to 50;

50, and the number of moles (X) plus (XI) ranges from 100 to 600 moles of (VI) plus (VII).

9. The composition of claim 1, wherein said polyethylene is about 0.1 to 2.0 percent by weight of said aromatic liquid crystalline polymer.

10. The composition of claim 1, wherein said aromatic liquid crystalline polymer contains repeat units derived from one or more of 4-hydroxybenzoic acid, 6- hydroxynapthoic acid, terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 4,4′

-bibenzoic acid, hydroquinone, chlorohydroquinone, methylhydroquinone, t-butylhydroquinone, phenylhydroquinone, phenethylhydroquinone, 4,4-biphenol, resorcinol, or 2,6-dihydroxynaphthalene.

11. The composition of claim 1, wherein said aromatic liquid crystalline polymer consists essentially of the repeat units:

wherein the molar ratio of (I);

(II) ranges from 0;

100 to 100;

0, wherein the molar ratio of (III);

(IV) ranges from 85.15 to 15;

85, wherein the molar ratio of the total of (I) and (II) to the total of (III) and (IV) is substantially 1;

1, and further wherein there are 100 to 600 moles of (V) per 100 moles of (I) plus (II);

12. The composition of claim 1, wherein said aromatic liquid crystalline polymer consists essentially of repeat units:

wherein the molar ratio of (VI);

(VII) ranges from 0;

100 to 100;

0, the molar ratio of (VIII);

(XI) ranges from 25.75 to 90;

10, the molar ratio of the sum of (VI) and (VII) to the sum of (VIII) and (XI) is substantially 1;

1, the molar ratio of (X);

(XI) ranges from 100 to 600 per moles of (VI) plus (VII);

13. The composition of claim 1, wherein said aromatic liquid crystalline polymer is selected from the group consisting of a polyester, a poly(imide-ester) and a poly(amide-ester).

14. The composition of claim 1, wherein glass fiber is present as said filler.

15. The composition of claim 1, wherein said filler is selected from the group consisting of glass fiber, carbon black, titanium dioxide, talc and combinations thereof.

16. The composition of claim 1, wherein said aromatic liquid crystalline polymer is a poltester.

17. A composition consisting essentially of:

a) thermotropic aromatic liquid crystalline polymer; and

b) from 0.05 to 2.5 percent by weight of said liquid crystalline polymer of polyethylene, said polyethylene having a molecular weight within the range between 1,000 to 10,000; and

c) optionally additional components consisting essentially of fillers, pigments and antioxidants,

wherein said composition, both with and without said polyethylene, has a flammability rating of V-O under the test conditions of UL-94 at a bar thickness of 0.079 mm (1/32 inch).

18. The composition of claim 17, wherein said polyethylene has a molecular weight within the range between 1,500 to 4,000.

19. The composition of claim 17, wherein said polyethylene is polar.

20. The composition of claim 17, wherein said polyethylene is about 0.1 to 2.0 percent by weight of said aromatic liquid crystalline polymer.

21. The composition of claim 20, wherein said polyethylene is about 0.2 to 1.0 percent by weight of said aromatic liquid crystalline polymer.

22. The composition of claim 17, wherein said liquid crystalline polymer is selected from the group consisting of a polyester, a poly(imide-ester) and a poly(amide-ester).

23. The composition of claim 22, wherein said filler is selected from the group consisting of glass fiber, carbon black, titanium dioxide, talc and combinations thereof.

24. A composition comprising:

a) a thermotropic aromatic liquid crystalline polymer having a flammability rating of V-O under the test conditions of UL-94, as revides on May 14, 1993, at a bar thickness of 0.079 mm (1/32 inch); and

b) from 0.05 to 2.5 percent by weight of said aromatic liquid crystalline polymer of polyethylene, and wherein;

i) said polyethylene having a molecular weight within the range between 1,000 to 10,000;

ii) said composition may optionally contain additional components including fillers, pigments and antioxidants; and

iii) said composition ratains the UL-94 flammability rating of V-O.

25. The composition as recited in claim 24, wherein said polyethylene has a molecular weight within the range between 1,500 to 4,000.

26. The composition as recited in claim 24, wherein said polyethylene is polar.

27. The composition as recited in claim 24, wherein the amount of said polyethylene is about 0.1 to 2.0 percent by weight of said aromatic liquid crystalline polymer.

28. The composition as recited in claim 24, wherein said aromatic liquid crystalline polymer is selected from the group consisting of a polyester, a poly(imide-ester) and a poly(amide-ester).

29. The composition as recited in claim 24 said filler is selected from the group consisting of glass fiber, carbon black, titanium dioxide, talc and combinations thereof.