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The advanced modification of domestic engineering plastics has been required with the rapid development of plastic industry in China. The mechanical properties and thermal stability of POM produced by blue star, Du Pont-Te, and Polyplastics, respectively, were compared in this paper. Flame retarded POM was prepared by addition of phosphorus-and nitrogen - containing flame retardants, and the flame retardancy, mechanical properties, and flame retardant were studied. The proportion and content of the flame retardants were determined by the experiments.In this study, the properties of the domestic and imported POM were measured, and its structures were analyzed by TGA, DSC, FTIR and NMR. There is no difference in the mechanical properties of domestic and imported POM, but the toughness of domestic POM exceeds imported POM. However, the thermal stability of blue star POM is worse than the imported POM.Flame retarded POM was prepared by addition of phosphorus -and nitrogen - containing flame retardants. The incompatibility of flame retardant and POM was solved by encapsulating of flame ret ardant with TPU. The influence of different char-forming agent on t he flame retardancy was studied.The flame retardancy of POM by a dding red phosphorus and MC just achieved a flammable of rating UL94Ⅴ-1. The flame retardancy of POM by additing of APP and MC can achieve UL94Ⅴ-0 rating, but the mechanical properties o f these two compounds decreased. The flame retardant mechanism was studied by TGA,SEM and FTIR,mainly contain membrane isol ation mechanism,dilution mechanism, free radical transferring mecha nism, and char mechanism.
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