HIGHLY THERMALLY-CONDUCTIVE MOLDABLE THERMOPLASTIC COMPOSITES AND COMPOSITIONS

• US 20110040007A1
• Filed: 05/04/2010
• Published: 02/17/2011
• Est. Priority Date: 08/17/2009
• Status: Active Grant

• Current Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Original Assignee: Laird Technologies Incorporated (DuPont de Nemours, Inc.)
• Inventors: Duraiswamy, Srinivasan, Kumar, Bambore Lokeshwarappa Santhosh, Ramachandraiah, Manjunatha Hosahalli, Chandrasekhar, Bukkinakere Kapanipathaiya
• Granted Patent: US 8,299,159 B2
• Time in Patent Office: Days
• US Class Current: 524/404
• CPC Class Codes: B29C 45/0001 characterised by the choice of material
• CPC Class Codes: B29K 2995/0013 Conductive
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H01B 1/24 the conductive material comprising carbon-silicon compounds, carbon or silicon

Abstract

Thermally-conductive moldable thermoplastic compositions or composites may generally include a plurality of metal-coated filler particles; a plurality of secondary filler particles; and a polymer matrix in admixture with the metal-coated filler particles and the secondary filler particles. The composition or composite may have a thermal conductivity ranging from about 20 Watts per meter-Kelvin to about 35 Watts per meter-Kelvin. Injection molded articles having a moldable thermally-conductive thermoplastic composition or composite can be formed for microelectronics, automotive, avionic, and other heat dissipation applications.

Claims

1. A moldable thermally-conductive thermoplastic composition comprising:

a plurality of metal-coated filler particles;

a plurality of secondary filler particles; and

a polymer matrix in admixture with the metal-coated filler particles and the secondary filler particles.

2. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the plurality of metal-coated filler particles comprise one or more of:

metal-coated graphite particles; and

/or

metal-coated perlite particles having one or more metal coatings; and

/or

combinations thereof.

3. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the plurality of metal-coated filler particles comprise perlite particles having a first metal coating and a second metal coating that is the same metal or a different metal than the first metal coating.

4. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the plurality of metal-coated filler particles comprise one or more of silver-coated graphite particles, silver-coated copper-coated perlite particles, nickel-coated copper-coated perlite particles, cobalt-coated copper-coated perlite particles, aluminum-coated copper-coated perlite particles, iron-coated copper-coated perlite particles, gold-coated copper-coated perlite particles, platinum-coated copper-coated perlite particles, palladium-coated copper-coated perlite particles, zinc-coated copper-coated perlite particles, or combinations thereof.

5. The moldable thermally-conductive thermoplastic composition of claim 1, wherein:

the plurality of metal-coated filler particles comprise one or more metal coatings of one or more of gold, silver, nickel, zinc, palladium, platinum, copper, iron, cobalt, aluminum, or combinations thereof; and

/or

the plurality of metal-coated filler particles comprise metal-coated perlite particles having a porosity ranging from 40% to about 99% or from about 80% to about 90%.

6. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the amount of the metal-coated filler particles and the secondary filler particles combined range from about 40% to about 80% or from about 50% to about 70% of the total thermoplastic composition by volume.

7. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the plurality of secondary filler particles comprises one or more of carbon fiber, boron nitride, graphite, nano graphite platelets, carbon nanotubes, carbon black, aluminum nitride, silicon nitride, aluminum oxide, magnesium oxide, or combinations thereof.

8. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the composition has a thermal conductivity ranging from about 10 Watts per meter-Kelvin to about 35 Watts per meter-Kelvin or from about 20 Watts per meter-Kelvin to about 35 Watts per meter-Kelvin.

9. The moldable thermally-conductive thermoplastic composition of claim 1, wherein the polymer matrix comprises one or more of acrylonitrile butadiene styrene (ABS) (chemical formula (C₈H₈.C₄H₆.C₃H₃N)_n);

polycarbonate/acrylonitrile butadiene styrene alloys (PC-ABS);

polybutylene terephthalate;

polyphenylene oxide;

polyphenylene sulfide (PPS);

polyphenylene ether;

modified polyphenylene ether containing polystyrene;

liquid crystal polymers;

polystyrene;

styrene-acrylonitrile copolymer;

rubber-reinforced polystyrene;

poly ether ether ketone (PEEK);

acrylic resins such as polymers and copolymers of alkyl esters of acrylic and methacrylic acid;

styrene-methyl methacrylate copolymer;

styrene-methyl methacrylate-butadiene copolymer;

polymethyl methacrylate;

methyl methacrylate-styrene copolymer;

polyvinyl acetate;

polysulfone;

polyether sulfone;

polyether imide;

polyarylate;

polyamideimide;

polyvinyl chloride;

vinyl chloride-ethylene copolymer;

vinyl chloride-vinyl acetate copolymer;

polyimides, polyamides;

polyolefins such as polyethylene;

ultra high molecular weight polyethylene;

high density polyethylene;

linear low density polyethylene;

polyethylene napthalate;

polyethylene terephthalate;

polypropylene;

chlorinated polyethylene;

ethylene acrylic acid copolymers;

polyamides, nylon, nylon 6, nylon 6,6;

phenylene oxide resins;

phenylene sulfide resins;

polyoxymethylenes;

polyesters;

polyvinyl chloride;

vinylidene chloride/vinyl chloride resins; and

vinyl aromatic resins such as polystyrene, poly(vinylnaphthalene), and poly(vinyltoluene);

polyimides;

polyaryletheretherketone;

polyphthalamide;

polyetheretherketones;

polyaryletherketone;

polycarbonate;

polyphenylene;

or combinations thereof.

10. A moldable thermally-conductive thermoplastic composition of claim 1, wherein:

the plurality of metal-coated filler particles are silver-coated graphite, the plurality of secondary filler particles are carbon fiber, and the polymer matrix is liquid crystal polymer;

or

the plurality of metal-coated filler particles are silver-coated copper-coated perlite, the plurality of secondary filler particles are boron nitride and carbon fiber, and the polymer matrix is liquid crystal polymer;

or

the plurality of metal-coated filler particles are silver-coated graphite and silver-coated perlite and the polymer matrix is liquid crystal polymer;

or

the plurality of metal-coated filler particles are silver-coated copper-coated perlite, the plurality of secondary filler particles are boron nitride and carbon fiber, and the polymer matrix is liquid crystal polymer;

or

the plurality of metal-coated filler particles are silver-coated copper-coated perlite, the plurality of secondary filler particles are carbon fiber, and the polymer matrix is polyphenylene sulfide;

or

the plurality of metal-coated filler particles are silver-coated graphite and silver-coated copper-coated perlite, and the polymer matrix is liquid crystal polymer;

or

the plurality of metal-coated filler particles are silver-coated graphite and the polymer matrix is liquid crystal polymer.

11. An article comprising the moldable thermally-conductive thermoplastic composition of claim 1.

12. A moldable thermally-conductive thermoplastic composition comprising a polymer matrix admixed with metal containing filler particles including one or more of silver-coated graphite, metal-coated perlite, and combinations thereof, the moldable thermally-conductive thermoplastic composition having a thermal conductivity greater than 20 Watts per meter-Kelvin.

13. The moldable thermally-conductive thermoplastic composition of claim 12, wherein:

the metal containing filler particles comprise perlite particles having a first metal coating and a second metal coating that is the same metal or a different metal than the first metal coating; and

/or

the metal containing filler particles comprise one or more of gold, silver, nickel, zinc, palladium, platinum, copper, iron, cobalt, and aluminum; and

/or

the metal containing filler particles comprise metal-coated perlite particles having a porosity ranging from 40% to about 99% or from 80% to about 99%; and

/or

the metal containing filler particles comprises perlite particles having first and second metal coatings, and wherein the weight of the metal particles of the first and second metal coatings ranges from about 100% to about 400% of the weight of the perlite particles; and

/or

the metal containing filler particles comprise perlite particles having a first copper coating and a second silver coating.

14. The moldable thermally-conductive thermoplastic composition of claim 12, wherein the polymer matrix comprises one or more of acrylonitrile butadiene styrene (ABS) (chemical formula (C₈H₈.C₄H₆.C₃H₃N)_n);

polycarbonate/acrylonitrile butadiene styrene alloys (PC-ABS);

polybutylene terephthalate;

polyphenylene oxide;

polyphenylene sulfide (PPS);

polyphenylene ether;

modified polyphenylene ether containing polystyrene;

liquid crystal polymers;

polystyrene;

styrene-acrylonitrile copolymer;

rubber-reinforced polystyrene;

poly ether ether ketone (PEEK);

acrylic resins such as polymers and copolymers of alkyl esters of acrylic and methacrylic acid;

styrene-methyl methacrylate copolymer;

styrene-methyl methacrylate-butadiene copolymer;

polymethyl methacrylate;

methyl methacrylate-styrene copolymer;

polyvinyl acetate;

polysulfone;

polyether sulfone;

polyether imide;

polyarylate;

polyamideimide;

polyvinyl chloride;

vinyl chloride-ethylene copolymer;

vinyl chloride-vinyl acetate copolymer;

polyimides, polyamides;

polyolefins such as polyethylene;

ultra high molecular weight polyethylene;

high density polyethylene;

linear low density polyethylene;

polyethylene napthalate;

polyethylene terephthalate;

polypropylene;

chlorinated polyethylene;

ethylene acrylic acid copolymers;

polyamides, nylon, nylon 6, nylon 6,6;

phenylene oxide resins;

phenylene sulfide resins;

polyoxymethylenes;

polyesters;

polyvinyl chloride;

vinylidene chloride/vinyl chloride resins; and

vinyl aromatic resins such as polystyrene, poly(vinylnaphthalene), and poly(vinyltoluene);

polyimides;

polyaryletheretherketone;

polyphthalamide;

polyetheretherketones;

polyaryletherketone;

polycarbonate;

polyphenylene;

or combinations thereof.

15. The moldable thermally-conductive thermoplastic composition of claim 12, wherein:

the moldable thermally-conductive thermoplastic composition has polymer matrix volume less than 40% by volume; and

/or

the moldable thermally-conductive thermoplastic composition has a polymer matrix volume varying from about 20% to about 40% by volume and an amount of metal containing filler particles ranging from about 40% to about 70%, the composition balanced to 100% volume with secondary filler particles, said composition having a thermal conductivity ranging from about 20 Watts per meter-Kelvin to about 35 Watts per meter-Kelvin; and

/or

the composition further comprises secondary filler particles including one or more of carbon fiber, boron nitride, graphite, nano graphite pellets, carbon nanotubes, carbon black, aluminum nitride, and combinations thereof.

16. An article comprising the moldable thermally-conductive thermoplastic composition of claim 12.

17. A method of producing moldable thermally-conductive thermoplastic composition having a thermal conductivity of at least 10 Watts per meter Kelvin, the method comprising mixing metal-coated filler particles and secondary filler particles in a polymer matrix.

18. The method of claim 17, wherein mixing comprises melt blending and/or solution blending

19. The method of claim 17, wherein:

the metal-coated filler particles comprise one or more of metal-coated graphite particles, metal-coated perlite particles having one or more metal coatings, silver-coated copper-coated perlite particles, silver-coated graphite particles, or combinations thereof; and

/or

the secondary filler particles comprise one or more of carbon fiber, boron nitride, and/or combinations thereof.