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采用改进的溶胶-凝胶法制备出平均粒径为150,180,200和250 nm 的 SiO 2微球,反应温度为20~50℃,正硅酸乙酯浓度为0．2~0．3 mol/L,反应后添加0．02％~0．04％(体积分数)的硅烷偶联剂 KH-570,再通过球磨将亚微米级 SiO 2均匀分散到 PEG(聚乙二醇)中,获得相应的抗撞击体系.利用 TEM、XRD、Physica MCR301型流变仪分别对不同粒径的SiO 2微球的粒度分布、结构以及流变性能进行测试,结果表明,粒径为200 nm 的 SiO 2微球制备的抗撞击体系粒度分布均匀,为非晶结构,并且表现出很好的剪切增稠现象.

In this paper,the SiO 2 particles were prepared by sol-gel method based on St?ber method by control-ling the reaction temperature,the amount of TEOS,the addition of a silane coupling agent KH-570.The result shows that 150,180,200 and 250 nm of silicon dioxide spherical particles can be attained when the reaction temperature is from 20 to 50 ℃,concentration of TEOS is from 0.2 to 0.3 mol/L,the amount of dispersant that added after the reaction is from 0.02 vol% to 0.04vol%.Then,the SiO 2 was dispersed in polyethylene glycol u-niformly by ultrasonic dispersion method,several factors which have influences on the rheological properties of the system,such as the particle size of SiO 2 ,the particle size distribution,the mass fraction of SiO 2 ,molecular weight of polyethylene glycol were studied.Finally we get the anti-impact material.The rheological experiments of sub-micro SiO 2 suspension in polyethylene glycol(PEG)show that the sub-micro SiO 2 with larger particle size and concentrated distribution,higher mass fraction of SiO 2 and PEG with greater molecular weight can be obtained anti-impact system with better shear thickening effect.