Studies On The Flame Retardation And Smoke Suppression Properties Of PVC

A1(OH)3 and Mg(OH)2 can be used as a kind of flame retardant having no halogen , anti-acid, have many properties such as flame retardation, smoke suppression etc. and the price is low, nonpoisonous, do not vaporize and can suppress the melting of the polymer. As a result, A1(OH)3 and Mg(OH)2 are widely used in many kinds of polymer to improve their flame retardancy. But the low efficiency of the inorganic hydroxides, the bad weakness in compatibility of the polymer, make the high amount of the filler be essential to acquire a good degree of flame retardancy. Because of the high loading are essential that good degree of flame retardancy be obtained, but mechanical properties decrease obviously. Using coupling agents and synergists are good ways to solving this problem.First, the flame retardation and smoke suppression of flexible PVC treated with Al(OH) 3 and Mg(OH)2 were studied with thermo analysis. The suitable type and amount of the coupling agent and the mechanism were discussed by comparing the mechanical properties and flame retardation, smoke suppression properties of the samples that treated with coupling agents with the sample which no coupling agents.Second, the flame retardation and smoke suppression properties of flexible PVC treated with various metal chelates were studied comparing with the common smoke suppression agent ferrocene combined with two compounds A1(OH)3 and Mg(OH)2. The mechanisms were studied through the char yield testing, scanning electron microscopy (SEM), thermogravity (TG) and differential thermal analysis (DTA). The effect on the mechanical and electrical properties of the flame retardant agents especially the metal chelates was studied. The flexible PVC treated with flame retardancants can be widely used in various ways.At last, the effects of the fillers nanomerric CaCO3 and micrometric CaCO3 on the flame retardation and smoke suppressantion, mechanical and the machining properties have been studied. The reason of nanometric CaCO3 enhanced the mechanicalproperties of flexible PVC that treated with flame-retardants were studied by SEM.