氢氧化铝复合阻燃剂对热硫化硅橡胶性能的影响

Effect of Al(OH)_3 on the flame-retarded property of RTV silicone rubber.

研究了氢氧化铝、氢氧化铝 /三氧化二锑并用、氢氧化铝 /三氧化钼并用对热硫化 (HTV)硅橡胶阻燃性能和力学性能的影响 ;试图在力学性能与阻燃性能之间寻找平衡。结果表明 :当 1 0 0份硅橡胶中氢氧化铝的用量为 80份时 ,硅橡胶的燃烧氧指数 (OI值 )可达 3 0 % ,但力学性能却受到严重损害 ,发烟量为B级 ;氢氧化铝 /三氧化二锑并用时 ,HTV硅橡胶的性能较理想 ;当 (氢氧化铝 +三氧化二锑 )用量为 5 0份时 ,硅橡胶的OI值为 3 1 %、拉伸强度为 6 3MPa、扯断伸长率为 660 %、撕裂强度为 2 3 7kN/m、邵尔A硬度为 5 7度 ,但发烟量为C级 ;氢氧化铝 /三氧化钼并用可使HTV硅橡胶燃烧时的发烟量达到A级 ,但不能显著提高其阻燃性能 ,当 (氢氧化铝 +三氧化钼 )用量为 96份时 ,HTV硅橡胶的OI值仅2 8% ,且此时其力学性能受到较大损害。

The effects of flame-retardants,which were Al(OH) 3 ,the blend of Al(OH) 3/Sb 2O 3 ,the blend of Al(OH) 3/MoO 3 ,on the flame-retarded properties of heat vulcanized (HTV)silicone rubber were studied,respectively,trying to seek the balance between the mechanical properties and flame-retarded properties.The results showed that the flame-retarded properties of silicone rubber could be improved and its oxygen index (OI) could reach 30%,yet its mechanical properties could be severely damaged with Class B fuming if Al(OH) 3 was 80 phr.When adding the blend of Al(OH) 3/Sb 2O 3 the property of silicone rubber was relatively ideal and when the blend of Al(OH) 3/Sb 2O 3 was 50 phr,the OI,tensile strength,elongation at break,tear strength and shore A hardness of HTV silicone rubber were 31%,6.3 MPa,660%,23.7 kN/m and 57 respectively,the level of smoke was C.Although the blend of Al(OH) 3/MoO 3 could effectively diminish the amount of smoke from C to A,it couldn't improve the flame-retarded property of silicone rubber,whose OI was 28,and badly damaged its mechanical properties.