二氧化硅/凹土纳米复合粉体的制备及应用

Preparation of SiO_2/Attapulgite Nanoparticles and its Uses in Sillicone Rubber

以硅酸钠为主要原料,用硫酸调pH值,通过液相沉淀法制备二氧化硅/凹土纳米复合粉体。以它为补强剂,采用机械共混法对甲基乙烯基硅橡胶(MVQ)进行填充,制备了具有优异力学性能的MVQ材料。利用XRD、FTIR、TEM、氮气吸附脱附曲线等方法对复合粉体进行表征。XRD分析表明,二氧化硅以非晶态的形式负载在纳米凹土表面。通过TEM分析表明,此方法可以有效防止凹土的团聚。氮气吸附脱附曲线表明,在凹土表面存在无晶型的二氧化硅粒子,同时凹土分散体之间也存在二氧化硅的聚集体,粒径大约在6～8 nm,复合材料可以作为硅橡胶的补强剂。

Attapulgite loaded with silica were successfully synthesized via the liquid deposition method using Na2SiO3 as the main raw material and sulfuric acid as the neutralization agent.The properties of the composites were studied by X-ray diffraction（XRD）,Fourier transform infrared spectromer（FTIR）,transmission electron microscopy（TEM）,N2 adsorption-desorption isotherms.Methyl-vinyl silicone rubber（MVQ） was reinforced with nanpowder as reinforcing filler.Even more excellent mechanical silicone rubber was prepared by means of mechanically compounding.XRD results show that there is noncrystal silica on the surface of nanoparticles and TEM results show that it prevents the nanoparticles from agglomerating.N2 adsorption-desorption isotherms showed that there is noncrystal silca on the surface of attapulgite and the particle diameters of the prepared nanometer silica were between 6nm and 8nm in the optimum condition.The nanpowder exhibited the better reinforcement to the MVQ and using the modified attapulgite as filler further improved the mechanical properties.