PEEK (Polyether Ether Ketone) is a semi-crystalline high-performance engineering plastic with alternating ketone and ether groups in its molecular chain. It offers exceptional heat resistance, mechanical strength, chemical resistance, and biocompatibility, with a moderate density among specialty engineering plastics. It is a core material for aerospace, automotive, electronics, medical, and petrochemical high-end applications. PEEK density is primarily affected by polymerization process, crystallinity, and filler modification. Virgin material density is stable, with a significant increase after glass or carbon fiber filling. Accurate density is critical for balancing lightweight design and strength in high-end precision components.

• Virgin PEEK: 1.30–1.32 g/cm3, typical value 1.31 g/cm3. It offers excellent heat resistance, high mechanical strength, and chemical resistance with moderate density, suitable for aerospace structural parts, medical implants, electronic connectors, and bearings.

• Glass Fiber Reinforced PEEK: 1.40–1.60 g/cm3. Density increases with glass fiber content, primarily improving tensile strength, rigidity, and dimensional stability while reducing the coefficient of thermal expansion. Ideal for high-load mechanical components and automotive engine parts.

• Carbon Fiber Reinforced PEEK: 1.35–1.55 g/cm3. Carbon fiber filling increases density, enhancing specific strength, wear resistance, and thermal conductivity for aerospace lightweight components, high-end bearings, and friction parts.

• Wear-Resistant Modified PEEK: 1.32–1.45 g/cm3. Composite fillers like graphite and molybdenum disulfide slightly increase density, optimizing friction coefficient and wear life for high-speed precision transmission components.

• Medical-Grade PEEK: 1.30–1.32 g/cm3. Purity optimization ensures stable density, primarily improving biocompatibility and sterilization resistance for orthopedic implants and surgical instruments.