Glass fiber-reinforced flame retardant PBT composition and preparation method thereof

Patent metadata

Field	Value
Publication number	US-10703901-B2
Application number	US-201615761333-A
Country	US
Kind code	B2
Filing date	Nov 16, 2016
Priority date	Nov 24, 2015
Publication date	Jul 7, 2020
Grant date	Jul 7, 2020

Abstract

The present invention discloses a glass fiber-reinforced flame retardant PBT composition which includes following components in parts by weight: 35 to 71 parts of a PBT resin; 5 to 30 parts of a flame retardant; and 5 to 50 parts of a glass fiber; based on a total weight of the glass fiber-reinforced flame retardant PBT composition, a content of tetrahydrofuran is less than/equal to 500 ppm and more than/equal to 10 ppm. In the present invention, when the content of tetrahydrofuran which is selected to be added in a formula of the glass fiber-reinforced flame retardant PBT composition, is less than/equal to 500 ppm and more than/equal to 10 ppm based on the total weight of the glass fiber-reinforced flame retardant PBT composition, a flowability and injection molding appearance of the glass fiber-reinforced flame retardant PBT composition can be apparently improved.

First claim

What is claimed is:

1. A glass fiber-reinforced flame retardant PBT composition, comprising following components in parts by weight:

a PBT resin
35 to 71 parts;

a flame retardant
 5 to 30 parts; and

a glass fiber
 5 to 50 parts,

a content of tetrahydrofuran less than/equal to 500 ppm and more than/equal to 10 ppm based on a total weight of the glass fiber-reinforced flame retardant PBT composition; and
wherein, flowability and injection molding appearance of the glass fiber-reinforced flame retardant PBT composition is improved as compared to when the content of tetrahydrofuran is more than 500 ppm based on the total weight of the glass fiber-reinforced flame retardant PBT composition,
wherein the PBT resin has an intrinsic viscosity of 0.5 dl/g to 1.5 dl/g and a density of 1.30 g/cm 3 to 1.33 g/cm 3 .

2. The glass fiber-reinforced flame retardant PBT composition according to claim 1 , wherein the flame retardant is a mixture of a halogen flame retardant and a flame retardant synergist; the halogen flame retardant is selected from one or more of a brominated epoxy resin, a brominated polystyrene and decabromodiphenyl ethane; and the flame retardant synergist is selected from one or more of antimony trioxide, antimony pentaoxide and sodium antimonite.

3. The glass fiber-reinforced flame retardant PBT composition according to claim 1 , wherein the glass fiber has a diameter of 5 μm to 15 μm.

4. The glass fiber-reinforced flame retardant PBT composition according to claim 1 , wherein it further comprises 1 to 2 parts of an adjuvant, and the adjuvant is selected from one or more of an antioxidant, a light stabilizer, a lubricant, a toughener and a nucleating agent.

5. The glass fiber-reinforced flame retardant PBT composition according to claim 1 , wherein the glass fiber-reinforced flame retardant PBT composition comprises the following components in parts by weight:

the PBT resin
40 to 57 parts;

the flame retardant
 9 to 23 parts; and

the glass fiber
10 to 40 parts;

wherein, the content of tetrahydrofuran is determined by a headspace gas chromatography: placing a certain amount of a sample in a liquid nitrogen biological container for 5 minutes and taking the sample out for smashing and screening to obtain a product with 30 to 40 meshes, and then weighing a certain amount of the product.

6. The glass fiber-reinforced flame retardant PBT composition according to claim 5 , wherein the flame retardant is a mixture of a halogen flame retardant and a flame retardant synergist; the halogen flame retardant is selected from one or more of a brominated epoxy resin, a brominated polystyrene and decabromodiphenyl ethane; and the flame retardant synergist is selected from one or more of antimony trioxide, antimony pentaoxide and sodium antimonite.

7. The glass fiber-reinforced flame retardant PBT composition according to claim 5 , wherein the glass fiber has a diameter of 5 μm to 15 μm.

8. The glass fiber-reinforced flame retardant PBT composition according to claim 5 , wherein it further comprises 1 to 2 parts of an adjuvant, and the adjuvant is selected from one or more of an antioxidant, a light stabilizer, a lubricant, a toughener and a nucleating agent.

9. The glass fiber-reinforced flame retardant PBT composition according to claim 5 , wherein based on the total weight of the glass fiber-reinforced flame retardant PBT composition, the content of tetrahydrofuran is less than/equal to 400 ppm and more than/equal to 20 ppm.

10. A preparation method for the glass fiber-reinforced flame retardant PBT composition according to claim 1 , characterized in that, the preparation method includes following steps:
a) preparing tetrahydrofuran and methylsiloxane into a solution of tetrahydrofuran/methylsiloxane, wherein a mass fraction of tetrahydrofuran in the solution of tetrahydrofuran/methylsiloxane is 20 ppm to 1000 ppm; and
b) mixing the solution of tetrahydrofuran/methylsiloxane with a PBT resin, a flame retardant and an adjuvant in a high-speed mixer for 1 to 2 minutes to obtain a premix, and the premix being melt and extruded at 220° C. to 240° C. in a double-screw extruder, side-fed with a glass fiber, cooled and pelletized to obtain the glass fiber-reinforced flame retardant PBT composition.

11. A preparation method for the glass fiber-reinforced flame retardant PBT composition according to claim 5 , characterized in that, the preparation method includes following steps:
a) preparing tetrahydrofuran and methylsiloxane into a solution of tetrahydrofuran/methylsiloxane, wherein a mass fraction of tetrahydrofuran in the solution of tetrahydrofuran/methylsiloxane is 20 ppm to 1000 ppm; and
b) mixing the solution of tetrahydrofuran/methylsiloxane with a PBT resin, a flame retardant and an adjuvant in a high-speed mixer for 1 to 2 minutes to obtain a premix, and the premix being melt and extruded at 220° C. to 240° C. in a double-screw extruder, side-fed with a glass fiber, cooled and pelletized to obtain the glass fiber-reinforced flame retardant PBT composition.

12. A preparation method for the glass fiber-reinforced flame retardant PBT composition according to claim 9 , characterized in that, the preparation method includes following steps:
a) preparing tetrahydrofiiran and methylsiloxane into a solution of tetrahydrofuran/methylsiloxane, wherein a mass fraction of tetrahydrofuran in the solution of tetrahydrofuran/methylsiloxane is 20 ppm to 1000 ppm; and
b) mixing the solution of tetrahydrofiiran/methylsiloxane with a PBT resin, a flame retardant and an adjuvant in a high-speed mixer for 1 to 2 minutes to obtain a premix, and the premix being melt and extruded at 220° C. to 240° C. in a double-screw extruder, side-fed with a glass fiber, cooled and pelletized to obtain the glass fiber-reinforced flame retardant PBT composition.

13. A preparation method for the glass fiber-reinforced flame retardant PBT composition according to claim 2 , characterized in that, the preparation method includes following steps:
a) preparing tetrahydrofuran and methylsiloxane into a solution of tetrahydrofuran/methylsiloxane, wherein a mass fraction of tetrahydrofuran in the solution of tetrahydrofuran/methylsiloxane is 20 ppm to 1000 ppm; and
b) mixing the solution of tetrahydrofuran/methylsiloxane with a PBT resin, a flame retardant and an adjuvant in a high-speed mixer for 1 to

Assignees

• Kingfa Science & Technology Co

Inventors

• Chen Rui
• Zhu Wen
• Chen Wei
• Chen Feng
• Fu Xuejun
• Sun Donghai
• Ye Nanbiao

Classifications

• C08L25/18

  Homopolymers or copolymers of aromatic monomers containing elements other than carbon and hydrogen · CPC title

• C08J5/043

  with glass fibres · CPC title

• C08K3/2279

  of antimony · CPC title

• C08L2201/02

  Flame or fire retardant/resistant · CPC title

• C08L67/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08L67/06 takes precedence) · CPC title