聚乙二醇对单分散球形氧化铝前驱体的影响

Influence of Polyethylene Glycol on Uniform Spherical Alumina Precursors

以硝酸铝、尿素及硫酸铵为主要原料,以聚乙二醇(PEG400、PEG2000及PEG20000)为分散剂,采用均匀沉淀法制备氧化铝前驱体.通过分散剂的空间位阻效应将新生成的粉末沉淀颗粒进行隔离,避免其靠近并络合.结果表明,不同分子量的PEG对单分散球形氧化铝前驱粉体的形貌的影响不同,达到最佳分散效果所用的分散剂的量也不同.其中效果最好的分散剂为PEG2000,最佳用量为1%.所制备的球形氧化铝前驱体的形貌为球形,粒度约为600 nm,为无定型态.

Alumina precursors were prepared via homogeneous precipitation, with Aluminum nitrate ,urea and ammonium sulfate as main materials and polyethylene glycol （PEG400, PEG2000 and PEG20000） as dispersant. By steric hindrance effect of dispersant, the new-prepared powders were separated, then avoiding the approaching and complexafion of powders. It was found that polyethylene glycol with different molecular weights had different effects on uniform spherical alumina precursors, and each need different amount to reach the best dispersing effect. PEG 2000 with 1% had the best effect, and the so-prepared precursors were spherical and amorphous with diameter of 600nm.