摘要 |
Polyoxymethylene with improved acid stability, process for production and use thereof. By adding 0.01 to 5 parts of an alkali metal salt of a polybasic acid, for example oxalic acid, citric acid and/or 0.01 to 5 parts of a polyalkylene glycol, for example polyethylene glycol and/or 0.1 to 100 parts of a thermoplastic polyurethane, each related to 100 parts of a polyoxymethylene, this polymer is stabilized against attack by acids, wherein in particular the combination of an alkali metal salt, in particular an oxalate, with small proportions of a thermoplastic polyurethane is advantageous. The proportion of thermoplastic polyurethane may be reduced when the thermoplastic polyurethane has a Shore A hardness of 70 to 96. The weight loss of a stabilized POM under the action of acid may be less than 3% of that of an unstabilized POM. The products are useful when exposed to acidic agents such as irrigation systems, dishwashers, sanitary installations.
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