Melt Shear History and Contaminant Catalyzed Scission in Post Consumer Polyolefin Silo Blends
Deactivate metal catalysts and neutralize acid traces with targeted additives to stabilize viscosity drift and optimize landed cost per good recycled part.
Copper Catalyzed Oxidation
Meaning
Thermal degradation pathways accelerate the reaction between oxygen and polymer molecules when transition metal ions are present. The reaction called copper catalyzed oxidation rapidly degrades polyolefins that are in direct contact with copper wires. This degradation appears as cracking and loss of flexibility in the plastic sheathing.
Avoiding contact with bare metal extends the life of the material.
Autoxidation Pathway
Polymer chains are stripped of hydrogen atoms by metal ions. When copper catalyzed oxidation begins, it generates free radicals that propagate through the polymer matrix.
Insulation Lifetime
Wire insulation must withstand elevated temperatures for decades without cracking or losing electrical resistance. In these electrical applications, copper catalyzed oxidation can cause premature failure of the protective plastic jacket. When the jacket cracks, moisture enters and creates short circuits.
This failure mechanism poses a serious risk to industrial wiring systems. Replacing damaged wiring increases maintenance costs significantly. Constant testing of the copper-plastic interface is required to ensure long-term durability.
Chemical Stabilization
Additive packages are incorporated into resins to prevent metal ions from interacting with the polymer structure. To counter copper catalyzed oxidation, compounders use specific chelating agents that bind to the metal surface. These additives deactivate the copper ions and prevent them from initiating radical reactions.
This shielding action ensures that the polymer maintains its physical properties over its intended service life.