The chemical resistance of PVC-U, PE and PP against disinfectants

GF Piping Systems have undertaken extensive tests to investigate the behaviour of a large number of commercially available disinfectants when transported in pipes and fittings made of PVC, PE and PP. Our tests on PVC have been supplemented by further tests carried out by the Henkel company, Düsseldorf. Results of earlier preliminary tests served as the basis, providing the following criteria:  Disinfectant solutions have a strong capillary force. Pipe joints must therefore be treated with extreme care. The make or type of disinfectant is likely to be changed several times during the operating life of such a piping system.  Different disinfectants have different compositions and behave differently towards plastics. The purpose of the experiments was to compile a planning guide taking into account the above criteria. For testing the resistance of the pipe material, the specimen was filled with disinfectant instead of water and long-term internal pressure tests were carried out as stipulated in the standards. The pipe joints suited to each pipe material were tested at the same time. Disinfectants are usually aqueous or alcoholic solutions containing special active agents against microbes. They usually also contain detergents, whose capillary force enhances the antibiotic effect. Chlorine separators may also be used, depending on the application. The pH value may vary within certain limits, from slightly acidic to slightly alkaline, but this has practically no effect on the resistance of the plastics. The tests encompassed pipes and fittings made of PVC, PE and PP as well as the appropriate joints. PVC-U (Polyvinyl Chloride) The different disinfectants investigated affected PVC in different ways. The long-term durability results for PVC with water...