Many companies using PCBs are very content making use of the standard material (FR4) for the boards. Sure, FR4 boards are very affordable, and can serve many applications. Bit, the truth is not, they aren’t the only material available for printed circuit boards. There are some others that may serve certain applications better.
One of such materials for boards is polyimide. It’s possible that some polyimide material properties for PCB will work fine for your specific industry’s board applications. If this is you first time making use of circuit boards, then you should get some knowledge concerning these boards, before you begin to order them
If you are here because you want to be sure if polyimide PCB is best for you, then continue reading. You will understand their properties, as well as the effects they can have on your applications.
What is Polyimide PCB Material?
Polyimides, which can also be called polyamides, are polymers that have imide monomers. Furthermore, this group includes different materials, which are both synthetic and natural. For example, wool and silk are examples of the natural polyamides. During the manufacturing of printed circuit boards, the Polyimides are mass-produced in a synthetic way.
You can produce synthetic Polyimides by the polymerization of different chemistries containing imide structures. Commonly, this process makes use of the maleic anhydride and bismaleimides.
Furthermore, the different additives and chemicals, which are useful during the process, can deliver varying results, thereby creating different Polyimides, which offer different benefits.
Below are some examples:
Left-Flow Polyimides: The Polyimides are made up of different flow restrictors and resins. These reduces the material’s flexibility
Filled Polyimides: The systems of Polyimides are made of a filler and Polyimide. The Polyimides delivers the needed flexibility and thermal resistance. However, the filler helps in reducing resin shrinkage. This helps in reducing cracks’ formation during the processes of drilling and curing.
3rd Generation Polyimides: Here, these include additives. These additives help in improving flammability resistance. This helps in preventing electrical fires. Though this type of Polyimides are less stable thermally, they provide improved times for production. This is possible because of their lower times and temperatures required for curing.
Pure Polyimides: These are also known as the 2nd generation type of Polyimides. Their production takes place without any brominated flame retardant, as well as other additives. Due to this, they are usually more temperature resistant and thermally stable compared to many alternatives today.
Soon, we expect more popularity for more variations of Polyimides. The 4th generation of Polyimides is under development currently. This helps in improving the adhesion of copper foil, as well as overall stability and moisture sensitivity.
When Should You Use Polyimides?
Across the PCB industry, there’s a high demand for Polyimide PCB products. This is mostly because of the strength and flexibility of the material. However, there are other reasons why people favor the use of Polyimides.
When you are choosing a base material for your PCB, make sure that you choose one that works best with the application. The most appropriate may be Polyimides of the application requires these PCB characteristics:
Great Tensile Strength: Polyimide materials are flexible. However, they still resist warping, and are very strong. This is one good reason why it is a great choice for applications requiring some physical durability.
Great Flexibility: The Polyimide materials are usually useful in the production of rigid-flex and flexible printed circuit boards. This is because of the very flexible nature of the material.
Highly Durable: Asides that Polyimide materials are resistant to chemicals and heat, the Polyimide PCB are very resistant to any physical stress. Regardless of whatever thermal and physical conditions you apply, they always maintain or retain their shape. This is why they are ideal for any application involving harsh field repairs and environments.
Resists Chemicals: Chemically, Polyimides are stable. This means that you can expose them to different corrosive materials. Also, this will not yield any negative effects. Furthermore, this is important in applications that include exposure to these chemicals.
Thermally Stable: Considering different temperatures, Polyimides are very stable. They have the capability to support operations at temperatures of about 260 degrees Celsius. In addition, they possess great thermal conductivity and have the ability to resist any thermal damages during the repair and manufacturing processes.
Asides these great properties above, Polyimides possess the required electrical properties, which make a great base material for your printed circuit board.
Polyimides PCB Material: Applications
Polyimides, both synthetic and natural, and useful in different applications. You can find these materials in consumer products, clothing, and vehicles. The most notable of its use is in PCBs (printed circuit boards). Below are the different applications where Polyimides is applicable in the printed circuit board industry.
The automobiles of today usually rely heavily on commonly use electronics and flexible PCBs in handling the heat and vibrations that usually occur in a vehicle.
Any computer environment, especially laptops need some durability and flexibility. This helps in withstanding the stresses of use every day. Furthermore, the environments where the computer PCBs usually operate could become very hot. This is why Polyimides rigid-flex and flexible PCBs work fine for these environments. This is mostly due to their thermal stability, durability, and flexibility.
A good number of medical applications need some flexibility in any electronics used. This is even more important in cases of imaging technology, prosthetics, and implants. This is because more movement is required here.
These include tablets and smartphones, which are usually made using rigid-flex or flexible PCBs. This was useful for their manufacturing because of the stresses incurred from everyday use. Furthermore, there is a further development of flexible PCBs to ensure potential consumer electronics for the future like smartphones and flexible tablets.
Aerospace and Military Electronics
The applications here usually have preference for Polyimides materials. This is due to their flexibility, thermal stability, and reliability.
To conclude, it is clear that Polyimides is very desirable for different applications. This is majorly due to its thermal capabilities, strength, flexibility, and durability.