Preparation and application of ferrites as flame retardants for flexible poly(vinyl chloride)

摘要

@@Flexible poly(vinyl chloride) (PVC) is extremely useful as a commercial material. However, an organic plasticizer such as dioctylphthalate (DOP) makes ignition and burning of PVC products easier. It is essential to make it flame-resistant. A large number of chemical compounds have been reported to be flame retardant and smoke retardant for PVC, but reports of the use of ferrites in flexible PVC are quite limited. In this paper, a series of ferrites (ZnFe2O4, MgFe2O4, NiFe2O4, CuFe2O4) were prepared with the method of wet air oxidation, and characterized by XRD. Flame retardant and smoke suppression of the ferrites in flexible PVC were characterized by LOI test and SDR test. Then thermal analysis was used to research the degradation process of PVC from 25 "C to 800 °C. The results show that ferrites especially MgFe2O4 have excellent flame retardancy and smoke suppression, and can obviously improve the formation and the stability of char residual.