PP low-temperature impact trials: specimen history matters
Impact figures are comparable only when specimen preparation, conditioning temperature and test method are recorded together. A result at one temperature cannot stand in for every transport or service condition.
Testing note
Impact figures are comparable only when specimen preparation, conditioning temperature and test method are recorded together. A result at one temperature cannot stand in for every transport or service condition.
In our comparison trials, the base resin and moulding conditions remain fixed. We record the failure appearance as well as the number, since a brittle break and a ductile deformation can lead to different formulation decisions even when the reported values are close.
Describe the lowest real service temperature
Provide the resin grade, part thickness, current impact result, test standard, conditioning time and the lowest temperature the part is expected to see. We can then set a sensible dosage ladder and check stiffness, appearance and processing alongside impact.