Antioxidants for Epdm Seals Exposed to Chlorinated Tap Water

Abstract

A suitable antioxidant for a poly(ethylene-co-propylene-co-5-ethylidene-2-norbornene) (EPDM) seal in tap water applications was determined with respect to volatilization and decomposition of the antioxidants. Seals were prepared by mixing EPDM with 1 phr antioxidant and other ingredients followed by vulcanizing the mixture at 433 K for 20 min. The resulting EPDM seals were immersed into chlorinated water to investigate accelerated degradation. The change in antioxidant content was measured by gas chromatography/mass spectroscopy (GC/MS) and high-performance liquid chromatography (HPLC). The weight loss of amine antioxidants during vulcanization was quite low due to their low volatility and decomposition. Antioxidant weight loss during accelerated degradation depended on both the antioxidant's ability to trap radicals and solubility in chlorinated water.

Study and characterization of LDPE/Polyolefin elastomer and LDPE/EPDM blend: effect of chlorinated water on blend performance

“…Some have been observed to resist degradation, while others degrade rapidly. 7,8 Additional results are available from Solvay technical bulletin that compare the performance of Polysulfone polymers and polyacetals in chlorinated environments. 9 The following materials have been evaluated: Polyvinylidene fluoride (PVDF) (Solef® 1010), Ethylene ChloroTriFluoroEthylene (ECTFE) (Halar® 350 LC), Polyphenylsulfone (PPSU) (Radel® R-5000), Polysulfone (PSU) (Udel® P-1700), Silane Crosslinked Polyethylene (PEX-b) (Polidan® T-A/SL), and Polyamide (PA12).…”

Degradation of Polymer & Elastomer Exposed to Chlorinated Water—A Review

“…Optical microscopic observations on surface indicate formation of black domain and increase in surface roughness in PP-R after exposed to 5000 ppm of chlorine and in PP-R/EBC and PP-R/ EPDM no changed was observed indicates the better resistant of blends to hot and cold chlorinated water. Mio Gonokami et al (2014) [146] investigated a suitable antioxidant for a poly(ethylene-co-propylene-co-5-ethylidene-2-norbornene) (EPDM) seal in tap water applications was determined with respect to volatilization and decomposition of the antioxidants. Seals were prepared by mixing EPDM with 1 phr antioxidant and other ingredients followed by vulcanizing the mixture at 433 K for 20 min.…”