Compositions containing liquid crystalline polymers

• US 6,833,405 B1
• Filed: 07/05/2000
• Issued: 12/21/2004
• Est. Priority Date: 07/31/1998
• Status: Expired due to Term

• Current Assignee: Ticona LLC (Celanese Corporation)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Cottis, Steve Gust
• Primary Examiner(s): SZEKELY, PETER A
• Application Number:
  US09/610,132
• Time in Patent Office: 1,630 Days
• Field of Search: 524/80, 524/84, 524/95, 524/100, 524/104, 524/111, 524/413, 524/497, 524/601, 524/604-605, 524/486, 524/106, 523/205, 523/210
• US Class Current: 524/497
• CPC Class Codes: C08K 2003/2241 Titanium dioxide
• CPC Class Codes: C08K 3/22 of metals

Abstract

Excellent tracking index as well as flame-resistant properties are achieved with other desirable characteristics of LCPs in a resin composition consisting essentially of: a) a wholly aromatic polyester which is melt processible and which displays anisotropy in the molten state; b) a non-conductive filler material having a diameter of less than about 3 m, with said non-conductive filler material being present in an amount sufficient to increase the comparative tracking index (CTI) rating of said composition to above 220 volts and render the composition non-burning. Optionally, an extraordinarily small amount of non-volatile fluorescent brightener can be added to the resin composition. In combination with the non-conductive filler, the fluorescent brightener is found to surprisingly and significantly improves the flame-retardant property of the resin. Such compositions are advantageously employed in electrical and electronic apparatuses.

Claims

1. An electronic or electrical apparatus, comprising:

a component formed from a liquid crystalline polymer composition consisting essentially of;

a) a thermotropic liquid crystalline polymer component which is an aromatic polyester, poly(ester-amide), poly(ester-imide), poly(ester-amide-imide), or mixtures thereof, and

b) 30 to 50 weight percent, based on the weight of the sum of a and b, of rutile titanium dioxide particles having a longest dimension of less than about 4 μ

m; and

an electrical conductor carrying a voltage of 200 volts or more.

2. The electronic or electrical apparatus of claim 1, wherein said liquid crystalline polymer (LCP) composition further comprises at least one fluorescent optical brightener:

having a boiling point of T_bp>

T_m−

60C, where T_m is the melting point of the LCP;

having one or more moieties derived from substituted anthracene, stilbene, triazine, thiazole, benzoxazole, coumarin, xanthene, triazole, oxazole, thiophene or pyrazoline; and

in an amount of greater than 0.005 wt. % based on the total weight percents of a) and b).

3. The electronic or electrical apparatus of claim 1 wherein said titanium dioxide particles have a diameter of about 0.1 to 0.3 μ

m.

4. The electronic or electrical apparatus of claim 1, wherein said thermotropic liquid crystalline polymer is a wholly aromatic polyester comprises repeating units derived from the group consisting of:

i) hydroquinone;

ii) 4,4′

-dihydroxybiphenyl (4,4′

-biphenol);

iii) isophthalic acid;

iv) terephthalic acid;

v) p-hydroxybenzoic;

vi) 4,4′

-dicarboxybiphenyl (4,4′

bibenzoic acid);

viii) 2,6-naphthalenedicarboxylic acid;

iv) 6-hydroxy-2-naphthoic acid, or combinations thereof.

5. The electronic or electrical apparatus of claim 1, wherein said voltage is about 250 volts or more.

6. The electronic or electrical apparatus of claim 1 wherein said titanium particles are coated with a metal oxide.