Liquid crystal polyester composition and process for producing the same

• US 8,545,719 B2
• Filed: 02/08/2012
• Issued: 10/01/2013
• Est. Priority Date: 02/28/2011
• Status: Active Grant

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: Komatsu, Shintaro, Fukuhara, Yoshiyuki, Harada, Hiroshi
• Primary Examiner(s): Visconti, Geraldina
• Application Number:
  US13/368,525
• Publication Number:
  US 20120217678A1
• Time in Patent Office: 601 Days
• Field of Search: 252/299.01, 252/299.6, 428/1.1, 349/1, 349/86, 349/167
• US Class Current: 252/299.01
• CPC Class Codes: C08G 63/605 the hydroxy and carboxylic groups being bound to aromatic rings
• CPC Class Codes: C08J 2367/00 Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
• CPC Class Codes: C08J 3/203 Solid polymers with solid and/or liquid additives
• CPC Class Codes: C09K 19/3809 Polyesters; Polyester derivatives, e.g. polyamides
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition

Abstract

The present invention provides a liquid crystal polyester composition, comprising (i) 100 parts by weight of a liquid crystal polyester, and (ii) 65 to 100 parts by weight of a combination of a fibrous filler with a plate-like filler, wherein the fibrous filler has a number-average fiber diameter of 5 to 15 μm, and a number-average aspect ratio of 20 to 40, and a content ratio by weight of the fibrous filler to the plate-like filler is more than 1.0 and 1.6 or less; and a process for producing the liquid crystal polyester composition comprising a step of melt-kneading the above respective components with one another.

Claims

1. A liquid crystal polyester composition, comprising:

100 parts by weight of a liquid crystal polyester; and

65 to 100 parts by weight of a combination of a fibrous filler with a plate-like filler;

wherein the fibrous filler has a number-average fiber diameter of 5 to 15 μ

m, and a number-average aspect ratio of 20 to 40, and a content ratio by weight of the fibrous filler to the plate-like filler is more than 1.0 and 1.6 or less.

2. The liquid crystal polyester composition according to claim 1, wherein the liquid crystal polyester contains a repeating unit represented by following formula (1), a repeating unit represented by following formula (2) and a repeating unit represented by following formula (3):

—

O—

Ar¹—

CO—

, 

 

(1)

—

CO—

Ar²—

CO—

, 

 

(2)

—

X—

Ar³—

Y—

, 

 

(3)

—

Ar⁴—

Z—

Ar⁵—

 

 

(4)

wherein Ar¹ represents a phenylene group, a naphthylene group or a biphenylylene group;

Ar² and Ar³ represent independently of each other a phenylene group, a naphthylene group, a biphenylylene group or a group represented by above formula (4);

X and Y represent independently of each other an oxygen atom or an imino group (—

NH—

);

Ar⁴ and Ar⁵ represent independently of each other a phenylene group or a naphthylene group;

Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group or an alkylidene group; and

one or more hydrogen atoms contained in the group represented by Ar¹, Ar² or Ar³ may be substituted independently of one another with a halogen atom, an alkyl group or an aryl group.

3. The liquid crystal polyester composition according to claim 2, wherein Ar¹ is a p-phenylene group or a 2,6-naphthylene group;

Ar² is a p-phenylene group, a m-phenylene group or a 2,6-naphthylene group;

Ar³ is a p-phenylene group or a 4,4′

-biphenylylene group, and both X and Y are an oxygen atom.

4. The liquid crystal polyester composition according to claim 2, wherein the liquid crystal polyester contains the repeating unit represented by formula (1) in an amount of 30 to 80% by mol, the repeating unit represented by formula (2) in an amount of 10 to 35% by mol, and the repeating unit represented by formula (3) in an amount of 10 to 35% by mol, provided that the total of the repeating units represented by respective formulas (1), (2) and (3) contained in the liquid crystal polyester is 100% by mol.

5. The liquid crystal polyester composition according to claim 1, wherein the fibrous filler is one or a combination of two or more selected from the group consisting of a glass fiber, a potassium titanate whisker, a wollastonite whisker and an aluminum borate whisker.

6. The liquid crystal polyester composition according to claim 1, wherein the plate-like filler is talc and/or mica.

7. The liquid crystal polyester composition according to claim 1, wherein the plate-like filler has a volume-average particle diameter of 10 to 30 μ

m.

8. The liquid crystal polyester composition according to claim 1, wherein the liquid crystal polyester composition further comprises 5 to 10 parts by weight of a granular filler, per 100 parts by weight of the liquid crystal polyester.

9. The liquid crystal polyester composition according to claim 8, wherein the granular filler is a glass bead.

10. The liquid crystal polyester composition according to claim 8, wherein the granular filler has a volume-average particle diameter of 5 to 50 μ

m.

21. A process for producing a molded article, comprising a step of injection-molding the liquid crystal polyester composition of claim 1.

22. The process according to claim 21, wherein the molded article is a connector.

11. A process for producing a liquid crystal polyester composition, comprising a step of melt-kneading (i) 100 parts by weight of a liquid crystal polyester, and (ii) 65 to 100 parts by weight of a combination of a fibrous filler with a plate-like filler, the fibrous filler having a number-average fiber diameter of 5 to 15 μ

m, and a number-average aspect ratio of 100 or more, thereby producing a liquid crystal polyester composition comprising;

100 parts by weight of the liquid crystal polyester; and

65 to 100 parts by weight of the combination of the fibrous filler with the plate-like filler;

wherein the fibrous filler has a number-average fiber diameter of 5 to 15 μ

m, and a number-average aspect ratio of 20 to 40, and a content ratio by weight of the fibrous filler to the plate-like filler in the liquid crystal polyester composition is more than 1.0 and 1.6 or less.

12. The process according to claim 11, wherein the liquid crystal polyester contains a repeating unit represented by following formula (1), a repeating unit represented by following formula (2) and a repeating unit represented by following formula (3):

—

O—

Ar¹—

CO—

, 

 

(1)

—

CO—

Ar²—

CO—

, 

 

(2)

—

X—

Ar³—

Y—

, 

 

(3)

—

Ar⁴—

Z—

Ar⁵—

 

 

(4)

wherein Ar¹ represents a phenylene group, a naphthylene group or a biphenylylene group;

Ar² and Ar³ represent independently of each other a phenylene group, a naphthylene group, a biphenylylene group or a group represented by above formula (4);

X and Y represent independently of each other an oxygen atom or an imino group (—

NH—

);

Ar⁴ and Ar⁵ represent independently of each other a phenylene group or a naphthylene group;

Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group or an alkylidene group; and

one or more hydrogen atoms contained in the group represented by Ar¹, Ar² or Ar³ may be substituted independently of one another with a halogen atom, an alkyl group or an aryl group.

13. The process according to claim 12, wherein Ar¹ is a p-phenylene group or a 2,6-naphthylene group;

Ar² is a p-phenylene group, a m-phenylene group or a 2,6-naphthylene group;

Ar³ is a p-phenylene group or a 4,4′

-biphenylylene group, and both X and Y are an oxygen atom.

14. The process according to claim 12, wherein the liquid crystal polyester contains the repeating unit represented by formula (1) in an amount of 30 to 80% by mol, the repeating unit represented by formula (2) in an amount of 10 to 35% by mol, and the repeating unit represented by formula (3) in an amount of 10 to 35% by mol, provided that the total of the repeating units represented by respective formulas (1), (2) and (3) contained in the liquid crystal polyester is 100% by mol.

15. The process according to claim 11, wherein the fibrous filler is one or a combination of two or more selected from the group consisting of a glass fiber, a potassium titanate whisker, a wollastonite whisker and an aluminum borate whisker.

16. The process according to claim 11, wherein the plate-like filler is talc and/or mica.

17. The process according to claim 11, wherein the plate-like filler has a volume-average particle diameter of 10 to 30 μ

m.

18. The process according to claim 11, wherein the liquid crystal polyester composition further comprises 5 to 10 parts by weight of a granular filler, per 100 parts by weight of the liquid crystal polyester.

19. The process according to claim 18, wherein the granular filler is a glass bead.

20. The process according to claim 18, wherein the granular filler has a volume-average particle diameter of 5 to 50 μ

m.

23. A process for producing a molded article, comprising a step of injection-molding the liquid crystal polyester composition produced by the process of claim 11.