Meaning
Chemical breakdown of polyetheretherketone occurs when the thermoplastic polymer is exposed to temperatures above its melting point or to aggressive chemical environments. This degradation process, peek matrix degradation, reduces the mechanical strength of the composite material. Limiting exposure to extreme environments preserves the long-term performance of the component.
Polymer Decomposition
Exposure to high temperatures triggers chain-scission reactions that shorten the polymer molecules. This polymer decomposition of peek matrix degradation causes the material to become brittle and lose its fracture toughness. Continuous operating temperatures must remain below the rated limits of the resin.
Structural Failure
Components subjected to mechanical loads can crack if the polymer matrix has lost its cohesive strength. The structural failure of peek matrix degradation appears as interlaminar cracking or delamination under load. Stress analysis must account for the degraded material properties.
Procurement Indemnity
Purchase contracts for aerospace thermoplastic composites contain clauses regarding material quality and process trace files. The procurement indemnity of peek matrix degradation protects the buyer if the supplier used incorrect processing temperatures. Process logs must be archived for traceability.
When thermal excursions are detected in the molding logs, the supplier must compensate the buyer for all testing and rework required to verify that the structural properties of the delivered batch were not compromised.
