Degradation Polyoxymethylene

chlorine attack of acetal resin plumbing joint

acetal resins sensitive acid hydrolysis , oxidation agents such mineral acids , chlorine. pom homopolymer susceptible alkaline attack , more susceptible degradation in hot water. low levels of chlorine in potable water supplies (1–3 ppm) can sufficient cause environmental stress cracking, problem experienced in both usa , europe in domestic , commercial water supply systems. defective mouldings sensitive cracking, normal mouldings can succumb if water hot. both pom homopolymer , copolymer stabilized mitigate these types of degradation.

in chemistry applications, although polymer suitable majority of glassware work, can succumb catastrophic failure. example of using polymer clips on hot areas of glassware (such flask column, column head or head condenser joint during distillation). polymer sensitive both chlorine , acid hydrolysis, may perform poorly when exposed reactive gases, particularly hydrogen chloride. failures in latter instance can occur seemingly unimportant exposures sealed joints, , without warning , rapidly (the component split or fall apart). can significant health hazard glass may open or smash. here, ptfe or high grade stainless steel may more appropriate choice.