丁二酸改性电子墨水用球形SiO_2颗粒的FTIR及XPS分析

FTIR and XPS Analysis of Modified Spherical SiO_2 Particles with Butanedioic Acid

采用丁二酸对球状亚微米级SiO2颗粒进行表面改性,以提高SiO2颗粒于四氯乙烯溶剂中的电泳性能,制备适于电子墨水用的白色电泳颗粒。利用傅立叶红外光谱(FTIR)、X射线光电子谱(XPS)和Zeta电位粒度仪,研究了丁二酸改性SiO2颗粒的表面键合情况及其在四氯乙烯溶剂中的Zeta电位变化情况。研究发现,丁二酸仅有一端的羧基与SiO2颗粒表面的羟基发生酯化反应,而且当丁二酸的用量为3g(50mL乙腈中)时,接枝于SiO2颗粒表面的丁二酸的量达到最大值,此时C1s(O—CO)/Si(原子比)有最大值为5.77×10-2。Zeta电位测试结果表明,丁二酸改性后的SiO2颗粒在四氯乙烯中的Zeta电位比改性前的SiO2颗粒提高了约5.5倍。

In order to improve the electrophoresis properties of the spherical SiO2 particles in tetrachloroethylene, the prepared spherical sub-micron SiO2 particles were modified by butanedioic acid. The binding patterns of SiO2 surface and the Zeta potential of modified SiO2 particles in tetrachloroethylene were studied by Fourier-transform infrared spectra （FTIR）, X-ray photoelectron Spectrometer （XPS） and Zetasizer. It is found that only one earboxyl of the butanedioie acid has esterified with the -OH, while the other carboxyl of the butanedioic acid hasn＇t reacted with the -OH which results in the improvement of the electrophoresis properties of the SiO2 particles. On the other hand XPS spectra indi cates that the atomic ratio of C1s （O-C=O）/Si possesses of the maximum value（5.77×10^-2） when the modified amount of butanedioic acid is 3 g in the 50 mL acetonitrile solvents. The Zeta potential of the butanedioic acid modified SiO2 particles in tetrachloroethylene medium was about 5.5 times more than that of the unmodified SiO2 particles.