|About this Abstract
||Materials Science & Technology 2019
||Failure Analysis: Industry Specific Failures
||Polymer Failures: Case Histories
||Fahmida Hossain, Veda-Anne Ulcickas
|On-Site Speaker (Planned)
Polymers have become unavoidable in daily lives. Manufacturers attempt to make durable components. Despite significant progress, failures routinely occur.
Service Related: Thermometers used in a hospital environment exhibited yellowish discoloration. Alcohol and phenol type disinfectants caused the discoloration. A clear polycarbonate window was attacked chemically by the disinfectants.
Improper Material: Improperly functioning controllers with built-in airflow sensors failed at the Santoprene seals. Santoprene is a mixture of EPDM with some polypropylene (PP). Maximum controller rating was 150°F. Elevated temperature exposure revealed leaching of EPDM from seals at ~120°F. A higher cured grade of Santoprene was recommended.
Inferior Material: Cracked plastic water supply fittings intended to be polyphenyl sulfone (PPSU) failed via environmental stress cracking (ESC). Silicone and carboxylic ester were identified as the ESC agents. The failed parts were a blend of PPSU and polysulfone (PSU). Generally PPSU is more resistant to environmental agents than PSU.