Polyimide (PI) is a class of high-performance polymers well known for their excellent thermal stability, electrical insulation, and mechanical properties, earning the title of “golden plastic.” With the development of micronization and chế biến bột technologies, polyimide has expanded beyond films, fibers, and coatings to include polyimide powder, further broadening its application scope, especially in composites, coatings, lubricants, and electronics.
Main Properties of Polyimide Powder
- Thermal Resistance
The decomposition temperature of PI powder typically exceeds 500°C, and it can maintain stable performance in the range of -200°C to 300°C. - Excellent Electrical Properties
It has a low dielectric constant and low dielectric loss, making it ideal for insulation and high-frequency applications. - Outstanding Hóa chất Sự ổn định
PI powder resists acids, alkalis, and organic solvents, with little chemical degradation. - Superior Mechanical Properties
With uniform kích thước hạt and a low friction coefficient, PI powder is suitable as a self-lubricating additive or reinforcing filler. - Functionalization Potential
Through surface modification or composite design, its dispersibility, conductivity, and thermal conductivity can be further enhanced.
Phương pháp chuẩn bị
Polyimide powder can be prepared using various methods depending on application needs:
- Chemical Precipitation
PI precursor solution is added to a precipitant, gradually forming powder.
High purity and controllable particle size, suitable for electronic-grade applications.
Drawback: complex process, high cost, best for small-scale high-end uses. - Mechanical Milling
Block PI is milled by máy nghiền phản lựcs, máy nghiền bis, or nhà máy tác độngs.
Mature process, easy operation, suitable for large-scale production.
Drawback: irregular morphology and wide particle distribution, requiring classification equipment. - Spray Drying
PI precursor solution is atomized into droplets, then dried and imidized at high temperature.
Produces spherical, uniform powder, suitable for coatings and 3D printing.
High yield and continuous process, good for industrialization. - Cryogenic Milling
PI is cooled to low temperature to increase brittleness, then mechanically pulverized.
Prevents thermal degradation and maintains structural integrity.
Often used for ultrafine and nano-scale powders. - Sol–Gel Method
Hydrolysis and condensation in solution form a 3D network, which is dried and heat-treated to obtain powder.
Produces high-surface-area, functionalized PI powders, widely used in composites and membranes.
Applications of Polyimide Powder
- High-Performance Coatings and Films
Dispersed in resins or solvents to create high-temperature, radiation-resistant insulating coatings.
Applied in spacecraft protective coatings, PCB insulation layers, and anti-corrosion coatings. - Tribological and Self-Lubricating Materials
Blended with PTFE, graphite, or MoS₂ to reduce friction.
Used in aerospace, automotive engines, and precision machinery for bearings, seals, and wear parts. - Electronics and Electrical Insulation
As a filler in epoxy resins and silicone rubber, PI powder improves thermal and dielectric properties.
Widely used in high-frequency circuits, 5G communication devices, and flexible printed circuits (FPCs). - Filtration and Separation Materials
Through sintering or electrospinning, PI powder produces high-temperature, chemical-resistant filtration media.
Applied in flue gas purification, chemical process filtration, and fuel cell membranes. - Additive Manufacturing (3D Printing)
Suitable for selective laser sintering (SLS) and other powder-bed fusion technologies.
Enables complex, heat-resistant parts for aerospace and automotive lightweighting. - Reinforcement in Composite Materials
Composited with metals, ceramics, carbon nanotubes, or graphene, PI powder enhances thermal and mechanical stability.
Promising for battery separators, high-performance substrates, and sensors.
Development Prospects
As demand for advanced powder materials increases, polyimide powder is evolving in several directions:
- Micro/Nano-Scale Control: Finer powders with narrower distributions for improved dispersibility in composites.
- Chức năng hóa: Surface-modified powders with conductivity, thermal conductivity, or magnetic properties.
- Green Processing: Energy-efficient, eco-friendly production methods aligned with sustainability goals.
- High-End Applications: Expanding into 5G communications, flexible displays, advanced energy storage, and aerospace.
Phần kết luận
With its outstanding thermal stability, electrical insulation, and mechanical strength, polyimide powder is becoming a cornerstone in advanced materials. At Bột Epic, we specialize in providing customized grinding and classification solutions—including jet mills, ball mills, and air classifiers—that enable the precise preparation of high-purity, ultrafine polyimide powders. By combining our 20+ years of expertise with innovative equipment, we help customers achieve stable, uniform powder performance tailored to demanding applications in electronics, aerospace, energy, and high-end composites. As the demand for high-performance powders continues to grow, Epic Powder is committed to driving innovation and supporting our partners in unlocking the full potential of polyimide powder.