Study On The Flame Retardant Properties Of Aramid Fiber/Fiberglass Needled Felt

Aramid fiber/glass fiber needled felt, as a high temperature filter bag, has a lot of goodperformance just like strong ability of dust filtering, high accuracy of filtering, good permeabilityand so on. However, because of the instability of filtering temperature, the needled felt can beburnt by the instantaneous high temperature and the good filtering performance is hard to last. Soin this paper retardant system such as Al（OH）₃, Mg（OH）₂, Sb₂O₃and etc. is used to deal with thearamid fiber/glass fiber needled felt in order to improve its flame retardant performance in thehigh temperature environment. And the performance of the filter-bag such as flame retardantperformance、mechanical properties and surface morphology in different condition is to beanalyzed and discussed.The experimental results show that, when the mass percentage of Al（OH）₃in flameretardancy finishing liquid is10%, the limit oxygen index （LOI） of filter cloth can be up to45.8%, but when the mass percentage of Mg（OH）₂is10%, the limit oxygen index （LOI） of filtercloth is just33.2%, so the effect of Al（OH）₃is obviously better than Mg（OH）₂on flame retardantfinishing.Through the test and analysis of limit oxygen index （LOI） and air permeability, it can befound that when the content of flame retardant reaches to10%¹5%, the flame retardantefficiency is very good and the air permeability doesn’t change a lot which have achieved thepurpose of improving flame retardant efficiency and filter efficiency in actual process, and withthe increase of the flame retardant, the flame retardant efficiency doesn’t improve a lot.Blending with different kinds of flame retardant can improve the flame retardantefficiency which can reduce their dosage and cost. The results of the burning phenomenon andlimit oxygen index （LOI） tests show that the effect of Sb₂O₃in flame retardant system is obviousand when the content of Sb₂O₃is5%, the LOI can be up to50.8%; however, the synergisticeffect of Al （OH）₃and Sb₂O₃of is not very obvious, but the smoke volume is reduced;2ZnO·3B₂O₃·3.5H₂O can not replace Sb₂O₃which has a much better flame retardant efficiency,but it can be used as synergist of Sb₂O₃to improve the flame retardant efficiency greatly; when Al（OH）₃：Sb₂O₃：2ZnO·3B₂O₃·3.5H₂O=1:2:2（weight ratio5%）, fabric’s limit oxygen index （LOI）can reach53.5%.