球形二氧化硅的制备与改性

正硅酸乙酯（TEOS）为硅原，在无水乙醇中通过氨水催化得到球形二氧化硅粒子。通过改变无水乙醇用量得到不同粒径的球形二氧化硅（SiO2），粒子粒径分布在180～300nm之间。反应过程中加入硅烷偶联剂KH-570对球形二氧化硅粒子改性，随着偶联剂用量的增加，在红外光谱图中1400cm^-1处出现峰值，说明亚甲基的C—H键特征峰强度增加了，二氧化硅粒子表面KH-570的有机官能团增加了，且KH-570对二氧化硅粒子起到了改性作用。将制备好的球形二氧化硅在氮气保护下用丙烯酸甲酯（MA）进行包覆，在红外谱图中1400cm^-1出现C—H键的特征峰，1800cm^-1，处也有了酯基的特征峰，说明球形二氧化硅粒子表面存在了丙烯酸甲酯的官能团，丙烯酸甲酯接枝到了二氧化硅表面。

Preparation and Modification of Si02 Spherical Particles

Nano-SiO2 spherical particles were prepared in the ethanol medium with ammonia as catalyst and tetraethoxysilane （TEOS） as silica source. The different diameters of the SiO2 spherical particles were obtained by changing ethanol dosage, the particle size distribution was in the range of 180 nm and 300 nm. During the reaction process, SiO2 spherical particles were modified by adding silane coupling agent （KH-570）, and the presence of the peak value was 1 400 cm^-1 in the infrared spectrograms with the increase of the concentration of silane coupling agent, it indicated that the strength of the characteristic peak of methylene （C-H） increased;KH-570 played a role in the modification of SiO2 particles, and furthermore, the organic functional group of KH-570 of the surface of SiO2 particles increased. The coating of the prepared SiO2 particles was operated in nitrogen with methyl acrylate,the presence of the characteristic peak of methylene （C-H） was 1 400 cm^-1and the presence of the characteristic peak of ester group was 1800 cm^-1 in the infrared spectrograms, it showed the surface of SiO2 spherical particles was coated with methyl acrylate.