Polyester resin composition, manufacturing method therefor, and camera module containing said polyester resin composition

Patent metadata

Field	Value
Publication number	US-10011715-B2
Application number	US-201314443811-A
Country	US
Kind code	B2
Filing date	Nov 19, 2013
Priority date	Nov 19, 2012
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

The purpose of the present invention is to provide a polyester resin with improved mechanical properties, molding performance, and, preferably, fire retardancy. This polyester resin composition contains the following: a polyester resin (A) that has a melting point or glass transition temperature of at least 250° C.; a thermoplastic resin (B) that has an olefin-derived constitutional unit and an aromatic hydrocarbon structure and has an intrinsic viscosity ([η]), as measured in decalin at 135° C., of 0.04 to 1.0 dl/g; and a copolymer (C) that has an olefin-derived constitutional unit, an α,β-unsaturated-carboxylic-ester-derived constitutional unit, and a cyclic oxy-hydrocarbon structure.

First claim

The invention claimed is:

1. A polyester resin composition comprising:
a polyester resin (A) which is derived from terephthalic acid and cyclohexane dimethanol and which has a melting point or a glass transition temperature of 250° C. or higher;
a thermoplastic resin (B) having a structural unit derived from ethylene and a structural unit derived from styrene and having an intrinsic viscosity [η] of 0.04 to 0.2 dl/g measured at 135° C. in decalin;
a copolymer (C) having a structural unit derived from ethylene, a structural unit derived from methylacrylate and a structural unit derived from glycidylmethacrylate; and
an inorganic filler (D),
wherein the content of the thermoplastic resin (B) is 1 to 5 parts by mass and the content of the copolymer (C) is 1 to 3 parts by mass, each based on 100 parts by mass of the total amount of the polyester resin (A), the thermoplastic resin (B), the copolymer (C) and the inorganic filler (D), and
wherein a flexural test piece formed by molding the polyester resin composition has a maximum flexural strength and a minimum flexural strength each falling within a range of ±2% of an intermediate value of the flexural strength, exclusive of 2%,
the flexural strength being measured using 4 flexural test pieces each being 64 mm in length, 6 mm in width, and 0.8 mm in thickness which is molded under conditions such that a molding machine cylinder temperature is 10° C.+melting point (Tm) of the polyester resin (A), a mold temperature is 150° C., and a residence time inside the molding machine cylinder is 1.5 minutes, 3 minutes, 5 minutes and 7 minutes, respectively, for the 4 flexural test pieces,
the flexural strength being measured at a span of 26 mm and a flexural rate of 5 mm/min using a flexural test machine at a temperature of 23° C. under a relative humidity of 50%, the maximum flexural strength being the largest value detected among the 4 flexural test pieces, the minimum flexural strength being the smallest value detected among the 4 flexural test pieces, and the intermediate value being calculated using the maximum flexural strength and the minimum flexural strength.

2. The polyester resin composition according to claim 1 , comprising:
30 to 80 parts by mass of the polyester resin (A);
1 to 5 parts by mass of the thermoplastic resin (B);
1 to 3 parts by mass of the copolymer (C); and
1 to 50 parts by mass of the inorganic filler (D), provided that the total of (A), (B), (C) and (D) is 100 parts by mass.

3. The polyester resin composition according to claim 1 , further comprising:
brominated polystyrene or polybrominated styrene (E); and
a flame retardant auxiliary (F).

4. The polyester resin composition according to claim 3 , comprising:
10 to 40 parts by mass of the brominated polystyrene or polybrominated styrene (E); and
1 to 20 parts by mass of the flame retardant auxiliary (F), provided that the total of (A), (B), (C) and (D) is set to 100 parts by mass.

5. The polyester resin composition according to claim 3 , wherein the flame retardant auxiliary (F) is at least one compound selected from the group consisting of antimony trioxide, antimony tetroxide, antimony pentoxide, sodium antimonate, zinc borate, zinc stannate, zinc phosphate, calcium borate, and calcium molybdate.

6. The polyester resin composition according to claim 3 , wherein the flame retardant auxiliary (F) includes sodium antimonate and zinc borate.

7. The polyester resin composition according to claim 1 , wherein
the thermoplastic resin (B) has an intrinsic viscosity [η] of 0.1 to 0.2 dl/g measured at 135° C. in decalin.

8. The polyester resin composition according to claim 1 , wherein
the polyester resin composition has a toughness of 22 to 53 mJ,
the toughness being measured using a test piece being 64 mm in length, 6 mm in width, and 0.8 mm in thickness which is molded under conditions such that a molding machine cylinder temperature is 10° C.+melting point (Tm) of the polyester resin (A) and a mold temperature is 150° C.,
the toughness being measured at a span of 26 mm and a flexural rate of 5 mm/min using a flexural test machine at a temperature of 23° C. under a relative humidity of 50%.

9. The polyester resin composition according to claim 1 , wherein when the polyester resin composition is molded into a test piece which is 64 mm in length, 6 mm in width, and 0.8 mm in thickness and which is molded under conditions such that a molding machine cylinder temperature is 10° C.+melting point (Tm) of the polyester resin (A) and a mold temperature is 150° C., the test piece is released from a mold, and minimum cooling time for releasing the test piece from the mold is 14 second or less.

10. A molded article obtained by molding the polyester resin composition according to claim 1 .

11. An electric or electronic component comprising an injection-molded article of the polyester resin composition according to claim 1 .

12. An automobile mechanism component comprising an injection-molded article of the polyester resin composition according to claim 1 .

13. A method of producing a polyester resin composition according to claim 2 , comprising: melting and kneading,
30 to 80 parts by mass of a polyester resin (A) which is derived from terephthalic acid and cyclohexane dimethanol and which has a melting point or a glass transition temperature of 250° C. or higher,
1 to 5 parts by mass of a thermoplastic resin (B) having a structural unit derived from ethylene and a structural unit derived from styrene and having an intrinsic viscosity [η] of 0.04 to 0.2 dl/g measured at 135° C. in decalin, 1 to 3 parts by mass of a copolymer (C) having a structural unit derived from ethylene, a structural unit derived from methylacrylate and a structural unit derived from glycidylmethacrylate, and
1 to 50 parts by mass of an inorganic filler (D), provided that the total of (A), (B), (C) and (D) is set to 100 parts by mass,
at a temperature 5° C. to 30° C. higher than a melting point of the polyester resin (A).

Assignees

• Mitsui Chemicals Inc

Inventors

• Washio Isao
• Ogasawara Hideto
• Ebata Hiroki
• Kageyama Fumio
• Takizawa Nobuhiro
• Amano Akinori

Classifications

• C08L23/0846

  with unsaturated hydrocarbons containing atoms other than carbon or hydrogen · CPC title

• C08L2207/04

  Thermoplastic elastomer · 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

• C08K3/013

  Fillers, pigments or reinforcing additives · CPC title