- COB LED Heat Sink
- SMD LED Heat Sink
- Lighting Housing
- Commercial LCD Display
plastic that conduct heat.
Removal application is one of the last thermoplastic fields-
Metal has not been replaced yet.
That\'s it until recently.
For a few companies, improving plastics to increase their thermal conductivity is an emerging field of opportunity.
They accepted the challenge of using plastic to solve heat accumulation problems in electronics, electrical appliances, lighting, automotive and industrial products.
In the pioneers, their heat
Conductive compounds have been on the market in the past few years, PolyOne.
, Cool polymer, LNP engineering plastics, RTP
And the Iron Company.
General Plastics, DuPont and.
Schulman is working on a development plan.
PolyOne formed a joint venture last month.
Development Agreement with cool polymer in order to design, hot-
Management testing and injection molding for prototype applications.
It is usually not considered that the thermal conductivity compound is a direct drop-
Instead, they open up broad new opportunities for \"thermal management\" applications.
Parts shaped by this new generation of materials can replace metals and ceramics in some applications, and do not
Conductive Plastic in other plastics.
Use include custom
Molded radiators on circuit boards, and pipes for electrical appliances, lighting, telecom equipment, commercial machines and industrial equipment heat exchangers used in corrosive environments.
Radiators often involve plastic.
Formed on a metal heat pipe.
The lighting application also includes reflector, laser-
Diode packaging and fluorescent ballast.
Car headlamp reflector is being developed.
In temperature sensors such as thermal resistors, a thermal conductive plastic package helps to improve the response of the temperature sensor itself.
Thermal conductivity compounds are also used to encapsulate small motors and motor wire shafts.
The diesel fuel pump uses thermal conductive plastic to help keep the fuel flowing in the submarine
More novel applications may include radiant flooring
Heating system, the thermal conductive film placed between the coils allows the water to operate at a lower temperature.
Another possibility is molding.
The plastic car radiator around the bumper profile is not a traditional square box.
New materials for heating and cooling
Transfer requirements ever made
Smaller and more powerful
Hungry Yao Electronics opened the door for this new generation of heat dissipation materials.
The thermal conductivity of the unfilled thermoplastic material is about 0. 2 W/mK (Watts/meter-[degrees]Kelvin)
, The conductivity of most thermal conductive plastic compounds is usually 10 to 50 times higher (1-10 W/mK).
The conductivity of a product offered by a company called Cool polymer is 100 to 500 times that of the base polymer (10-100 W/mK).
Traditionally, aluminum has always been the main material to control higher heat flow in electronic products.
Thermal conductivity of extrusion
Grade aluminum alloy is close to 150 W/mK. Some die-
Cast metal alloy (
Magnesium or aluminum)are in the 50-100 W/mK range.
However, it can be argued that if the metal passes heat to the surface of the product at a faster rate than the air, the high thermal conductivity of the metal cannot be effectively utilized
Flow convection can remove heat from the surface.
According to Jim Miller, cool polymer product manager, \"Heat transfer in many applications is convection-limited (Design-dependent)
Not conduction. limited (material-dependent).
\"His Company demonstrated this concept in some applications where thermal conductive plastics provide heat transfer equivalent to aluminum and copper designs.
Mark Kaptur, marketing manager for LNP products, added, \"where conductivity is a limiting factor, metals are the preferred material.
But in many applications, convection is the limiting factor, and then it is more suitable for conducting plastic.
In addition, the thermal conductive plastic usually has a lower thermal expansion coefficient (CTE)
Therefore, plastic is closer to the CTE of silicon or ceramics they contact than aluminum, thus reducing the stress caused by the expansion difference.
The weight of conductive plastics is also 40% lighter than that of aluminum;
They provide design freedom for molding
Integration of functions and components;
They can eliminate expensive after
According to cool polymer Miller, many technological advances using microchips are not possible without thermal conductive plastics.
\"This ability to control heat --
Also available is light, flexible and low
Cost applications will make these plastics one of the most important technological developments in the coming decades.
\"Infrared photography of cool polymers shows the cause of overheating and failure of many components made of plastic (see photos, p. 53).
Apply the field heat source to the center of the plate molded panel-
One is made of standard PP and the other is made of cool Poly heat-conducting PP compound.
The latter removes the heat from the central hot spot to produce a more constant temperature profile of no more than 4 [degrees]
C. The whole group.
But the standard PP panel shows 24 [degrees]
C. The temperature difference between the hottest point and the coolest point.
At present, high initial cost is the biggest obstacle to widespread acceptance of thermal conductivity compounds.
One key factor is high.
Pricing filler for achieving good thermal conductivity, resulting in the cost of these compounds being at least twice and a half as much as metal or ceramic materials.
Many thermal conductivity compounds cost $25-
In the range of $45/lb, although some of the lower conductivity costs only $4 to $6/lb.
The supplier says the technology is currently best suited for high
Mass production (e. g.
, 10,000 pieces/month)
In order to achieve the design and manufacturing advantages of injection molding.
Miller of cool polymer said that up to 30% of the cost savings have been achieved in replacing metal designs.
However, he noted that the part size could have a critical impact.
\"For a small part, most of the cost is in the injection molding process, and for the larger part, the material is the biggest factor.
Due to the high cost in the early stage, thermal conductive plastics have advantages for smaller units-up to l-lb.
\"The most commonly used active ingredient in heat --
The conductive additives are graphite carbon fiber and ceramics such as alumina and bn.
Graphite fibers conduct electricity and heat, suitable for applications that require RFI shielding, such as manual
Handheld communication devices.
In contrast, ceramic additives are electrically insulated.
They are suitable for applications in contact with wires.
Almost all suppliers of thermal conducting compounds offer conductive and insulating types.
Thermal conducting compounds, due to their high heat resistance and low melt viscosity, are usually prepared with crystal engineering resin, but amorphous resin can also be used.
Cool polymers, for example, have developed a heat-conducting polysulfur compound.
In general, conductive compounds have higher stiffness and strength than unfilled or glass, but lower impact properties
For example, a glass
The notch impact of the reinforced nylon 66 is about 1. 7-1. 8 ft-lb/in.
The gap Izod of thermal insulation nylon 66 is 1. 0 ft-lb/in.
The most thermal conductivity additives are special graphite fibers made of petroleum asphalt.
The conductivity value is 500 1000 W/mK.
In contrast, the structure-
Grade carbon fiber based on pan (PAN)
The conductivity is less than 10 W/mK.
The thermal conductivity of electrical insulating ceramic filler is 60-
Boron nitrogen powder is 80 W/mK and aluminum nitrogen powder is 300 W/mK.
According to Sam Johnson, BP\'s carbon fiber industry composite industry manager, most commercial uses of asphalt graphite fibers require conductivity to be within the range of 500 W/mK.
This usually requires high fiber load (up to 70%).
Johnson said that even at such a high load, crystalline plastics such as crystalline and PPS may have quite a long flow path because they have excellent interface compatibility with graphite fibers.
Johnson added, \"you don\'t need to cool the mold because these fibers are very heat-conducting.
As a result, the compounds circulate rapidly.
\"BP is currently the only stadium manufacturer in North America.
ConocoPhillips aims to start production of special asphalt fibers at a new plant in the city of orclamonka, becoming the second source.
Early next year.
Despite BP\'s heat map
BP has developed a low fiber for about $25/lb.
The cost process will reduce prices by at least 25%, Johnson said.
BP is expected to start using the new process early next year.
Ceramic filling is also expensive.
The price of alumina is about $20 per pound, while the average price of boron nitrogen is about $50 per pound.
Juyoung Kim, technical development manager, advanced refractory technology company, said that since the particle shape of the former filler is more rounded, while the latter\'s platelet shape, the flow of nitrogen-aluminum compounds is greater than that of compounds containing boron and nitrogen.
\"As a result, you can easily get a load of up to 60% of the volume of alumina, while the volume of boron nitrogen is up to 20%,\" Kim claims . \".
His company is the only American company. S.
Supplier of alumina.
The new development version, Maxtherm, will allow higher load and greater thermal conductivity, Kim said.
It will be available later this year.
Advanced Ceramics Company
It is treated on the new surface to make boron nitride (BN)
Don Lelonis, director of marketing, said to load and maintain good molding at a high enough level.
In order to optimize the thermal conductivity, efforts are also being made to modify the shape and size of BN particles. (
The only other USS.
Supplier of Saint-boron nitrogen
Goban advanced ceramics company, formerly known as Car borundum. )
Graphite fiber and ceramic filler have grinding effect on the processing equipment.
Molder can be used by low
Compression screws and avoid small gates and inspection rings.
Johnson suggested that cutting should be minimized in general.
Kaptur of LNP added, \"the biggest difference in handling these com pounds is that they cool very fast in injection molds because they heat transfer very quickly.
So once they stop flowing, they don\'t start flowing again.
In mold design, this is a consideration, such as where you put the vents and gates.
\"The scope of the polymer expands the heat-
The focus of conductive thermoplastic materials is high heat-
Resistant resin such as LCP, PPS, peeping and polybenzene.
PolyOne is also testing new compounds based on polyethymide (GE\'s Ultem).
Suppliers are now expanding their scope, including
Temperature resin such as abs, pet, pc and nylon, and resin with lower temperature
Temperature commodity plastics like PP and PS.
Even TP rubber gets hot.
Cool polymer Miller said, \"in the middle
Temperature engineering resin group, our goal is to apply radiator in smaller steps
Motors for various industrial equipment.
In the field of commodity resin, we see PP-
Compounds and possible PS based on non-
Electronic applications such as food
Related consumption heating and cooling products.
\"Today\'s cool polymer cool Poly line includes compounds from LCP, nylon 66, PC/ABS and PPS.
They provide thermal conductivity up to 60 W/mK depending on the type of resin.
Elastic TPO compounds are being developed.
The company offers a grade of thermal conductivity customized for any engineering or commodity thermoplastic.
The Konduit series of LNP includes grades PPS, PP and Nylon 6 and 66.
These resins are compounded with carbon, ceramic or metal fillers and a small amount of glass-reinforced materials if required. A lower-
The cost Product Group provides thermal conductivity up to 2 w/mK using ceramic or metal additives. A high-
The performance product group uses dedicated carbon fiber to reach 10 W/mK.
LNP can provide custom Konduit products in any crystalline thermoplastic.
Therma of Polon-
The Technical Series includes compounds of LCP, PPS and PPA (BP\'s Amodel)
Thermal conductivity up to 10-12 W/mK.
The newly added content includes TPV (
Flexible cross-linking TPO).
Thermal plastic conductive compounds of RTP (TCC)
Can be customized production line with PPS, LCP, PPA, PC, nylon.
66, PP, PE, TPEs (
Olefinic or styrenic).
Unlike most suppliers, RTP has a conductivity range of up to 18 W/mK, providing conductive compounds for injection molding and extrusion.
An example of the latter is the PP compound used for piping paints and adhesives that must maintain a constant temperature.
Ticon offers four Fortron PPS grades with a thermal conductivity of up to 3.
0 W/mK in electrical insulation or conductive version.