As manufacturers increase the operating temperature of chlorine production to improve yields, the service life of traditional fiberglass-reinforced plastic (FRP) gas ductwork has decreased by as much as 50%. The purpose of this paper is to report the results of a pilot plant investigation of FRP laminates exposed to chlorine gas and anolyte produced by membrane cells operating at 100°C (212°F). Materials demonstrating potential for longer service life in on going case studies were chosen for the pilot plant study. This investigation was conducted to compare laminates made with the various materials for weight, thickness, and appearance changes when exposed to wet chlorine gas and anolyte at 100°C for up to 180 days. The experimental variables included:
1) Three thermoset resins
2) Five surfacing veils
3) Two resin cure systems
The above variables included a polyester resin system that has long been the industry standard for chlorine ductwork construction. The study showed that ductwork based on an epoxy novolac vinyl ester resin with a double c-glass veil and a 100°C post-cure should be satisfactory for service in chlorine gas at 100°C.
Keywords: anolyte, chlorendic, chlorine, epoxy vinyl ester, FRP, fiberglass, membrane, novolac,plastic, polyester, reinforced, and resin