Meaning
Polyetheretherketone represents a high performance semicrystalline thermoplastic noted for chemical resistance and thermal stability. Engineers select peek when applications require sustained mechanical strength under extreme temperatures or exposure to aggressive solvents. Its molecular structure contains repeated units of aromatic rings linked by ketone and ether groups.
This backbone grants durability across a wide temperature range exceeding three hundred degrees Celsius.
Material Properties
Thermal degradation thresholds define the practical upper limit for this resin during processing cycles. Moulders maintain barrel temperatures around four hundred degrees Celsius to ensure proper flow and avoid crystalline inconsistencies. Degradation symptoms include brittleness in finished parts and darker colour shifts during the injection cycle.
Virgin resin pellets exhibit consistent melt indices that allow for predictable pressure drops through a standard gate. Regrind content introduces contaminants that lower the total service temperature of the moulded component.
Production Logic
Tooling design requires high heating capacity because the material freezes rapidly upon contact with colder metal surfaces. Cavity pressure needs precise calibration to prevent the formation of internal voids during the cooling phase. An uneven wall thickness creates local stress concentrations that lead to premature fatigue failure in the field.
Shops verify the crystallinity of samples through differential scanning calorimetry to confirm that cooling rates matched the specific grade requirements.
Part Specification
Finished components differ from raw granules by the specific orientation of polymer chains induced during the filling stage. Datasheet values provide a baseline for isotropic behaviour while the actual part performance depends on flow path geometry and gate location. Dimensional stability remains stable because the resin absorbs minimal moisture compared to polyamides or other technical plastics.
Reliable performance depends on the control of cooling rates within the tool rather than solely on the choice of resin grade.
