Study On The Synergetic Flame Retardancy And The Flame Retardant Mechanism Of SBR

Environmental friendly flame retardant with low smoke, low toxicity and highefficiency is one of the most important developing directions of SBR and otherpolymer materials.The LOI of SBR is19%only. At present, flame retardant SBRmainly underlies brominated flame retardants which are contaminative. In this paper,Decab romodiphenylethane （DBDPE）/Antimony trioxide （Sb₂O₃）, Aluminumhydroxide （Al（OH）₃）/red phosphorus（P） and P-N intumescent flame retardant （IFR）were selected as the main flame retardants for SBR. The burning behavior,thermo-gravimetric behavior, thermal degradation kinetic and char structure of flameretardant SBR were studied by various approaches such as cone calorimeter testing（CONE）, UL-94vertical burning test, TG and SEM, in order to get appropriateflame retardant SBR according to different requirement. And the flame retardantmechanism and the synergistic effect were also discussed. There studied flameretardant systems present as follows.1.The high efficient flame retardant SBR by DBDPE/Sb₂O₃were studied.Results showed that, the shape of HRR curves of flame retardant SBR byDBDPE/Sb₂O₃was “single peak behind”, which indicated a typical gasflame-retardant mechanism with increasing somke during burning. The sample ofSBR with DBDPE/Sb₂O₃degraded at a relatively low temperature，and there wasprismatic material in carbon residue after burning2.The low-smoke and halogen-free flame retardant SBR by APP/PER andAl（OH）3/P were studied. Results showed that, when the mass ratio of ammoniumpolyphosphate （APP） and pentaerythritol （PER） was3:1, the flame retardant effects of SBR/IFR were higher than others. While for the SBR/Al（OH）3/P system,the theoptimal mass ratio was26:14. The Al（OH）3/P flame-retardant effect to SBRoccurred at300⁵00℃,for that the aluminum phosphate,the product after thereaction of Al（OH）3and P, prevented the SBR from degradation.The IFR revealed itsflame-retardant effect at500℃⁸00℃.The formed carbon layer inhibited thedegradation of carbon black.Certain synergistic effect appeared when the twosystems worked together. And the1:1mass ratio of IFR and Al（OH）3/P performedbest.3.The low-halogen and high efficiency flame retardant SBR by DBDPE/Sb2O3、IFR and Al（OH）3/P was studied. The LOI of SBR by DBDPE/Sb2O3/IFR/Al（OH）3/Pcan reach to27. UL-94can pass V-2and HRR was significantly slower, hence goodflame-retardant effect achieved. The variety of flame retardants displayedflame-retardant effect at different temperature range, via increasing the carbonresidue and the stability of carbon layer.