What is ZST (Zero Strength Time) in PCTFE polymer testing?

ZST (Zero Strength Time) refers to the time required for a polymer test specimen, suspended vertically with a weight at its lower end, to break under the effect of heat. This measurement is performed at high temperature and allows the moment at which the material loses all mechanical strength to be assessed.

Why is the ZST important for PCTFE-based polymers?

ZST is a critical indicator for characterizing the molecular weight of polymers based on PCTFE (polychlorotrifluoroethylene). Well-controlled molecular weight is essential to guarantee the mechanical performance, thermal stability, and durability of PCTFE components, particularly in demanding environments such as aerospace and space.

What are the industry standards associated with ZST?

ZST measurement is often used in conjunction with other thermal and mechanical characterization tests. It is particularly relevant in the context of the quality standards imposed by the aerospace and defense sectors, where the reliability of polymer materials is crucial.

How is ZST measured at DEMGY?

A machine dedicated to measuring ZST will be integrated into DEMGY's facilities from the end of September 2025. This acquisition will enable the implementation of a rigorous control methodology for PCTFE products, in accordance with customer requirements and industry standards.

What are the advantages of this approach for industrial customers?

•    Increased reliability of PCTFE components in extreme environments (high temperatures, vacuum, chemical agents). • Molecular weight traceability for each production batch. • Compliance with customer requirements in critical sectors (aerospace, defense). 
•    Reduced risk of failure in service thanks to enhanced quality control.