Skip to main content

Recently, I worked on a failure analysis of a part injection molded from a poly(ethylene:chlorotrifluoroethylene) copolymer (ECTFE) used in a chemical transport application. While I am generally familiar with this material, I was looking for some additional background. I found three great sources:

  • The book, “Technology of Fluoropolymers” by Jiri Drobny
  • The online database, “”
  • The “Halar® ECTFE Design & Processing Guide” from Solvay

ECTFE molecular structureECTFE is a partially fluorinated, semi-crystalline plastic resin which offers a relatively unique property set:

  • Chemical resistance
  • Fire resistance
  • Broad continuous use temperature
  • Good impact resistance
  • Electrical insulator
  • Melt processable

As part of the failure investigation, I performed a dynamic mechanical analysis (DMA) temperature sweep. DMA is an extremely useful thermal analysis technique to evaluate polymeric materials. It provides information on the physical properties (modulus) of the material across a wide temperature range. This is valuable in understanding how the material will behave with temperature and time.

The obtained results indicated that the material underwent a relatively stable reduction in storage modulus with increasing temperature through approximately 50 °C, representing the onset of the glass transition within the material. A glass transition temperature of 79 °C was determined, by convention, as the localized maximum in the loss modulus. From 50 °C, the material underwent a steady decline in modulus with increasing temperature through approximately 100 °C. Above 100 °C, the rate of modulus reduction declined. This is expected to continue through crystalline melting. Overall, the observed performance was consistent with that generally expected for a semi-crystalline polymer passing through glass transition and approaching melting. Specifically, the behavior was in agreement with that expected for an ECTFE resin.

ECTFE DAM temperature sweep

Jeffrey A. Jansen

Jeffrey A. Jansen is the Engineering Manager and a Partner at The Madison Group. He was elected as a Fellow of the Society by the Society of Plastics Engineers. Jeff is a proven plastic professional with more than 30 years of experience solving problems and addressing opportunities related to polymeric materials. He specializes in failure analysis, material identification and selection, as well as compatibility, aging, and lifetime prediction studies for thermoplastic materials. Jeff has performed over 5,000 investigations, both for industrial clients and as a part of litigation. He regularly presents seminars and webinars, covering a wide range of topics related to plastics failure, material performance, testing, and polymer technology. Jeff is a graduate of Carroll College and the Milwaukee School of Engineering.