PMMA/SiO_2纳米复合膜表面性能的研究

采用有机硅处理剂对纳米SiO2进行化学修饰,得到表面官能团化的纳米SiO2,然后再通过溶液聚合法制备了聚甲基丙烯酸甲酯/二氧化硅(PMMA/SiO2)纳米复合膜.利用傅里叶红外光谱仪(FT-IR)、扫描电镜(SEM)、原子力显微镜(AFM)、水接触角仪(WCA)对其进行表征.结果表明,经有机硅处理剂官能团化的纳米SiO2能很好地分散于PMMA基体中,SiO2有富集到聚甲基丙烯酸甲酯表面的趋势,加入纳米SiO2降低了聚甲基丙烯酸甲酯表面自由能,提高了膜表面的水接触角.经四氢呋喃溶剂刻蚀后,膜表面的水接触角显著提高,得到憎水型PMMA/SiO2纳米复合膜.

Surface properties of PMMA/SiO_2 nanocomposite films

In order to obtain functionalized nanosilica,the organic silicon coupler was employed.The functionalized nanosilica can be further polymerized with methylmethacrylate(MMA) monomer to prepare well-defined PMMA/SiO2 nanocomposite films via solution polymerization.The properties of the films were characterized by Fourier transform infrared spectroscopy(FT-IR),scanning electron microscope(SEM),atomic force microscope(AFM) and water contact angle measurements(WCA),respectively.The results!show that nanosilica particles,which are modified by the organic silicon coupler,are well dispersed in the PMMA matrix,as well as the nanosilica particles can enrich on the surface of PMMA/SiO2 nanocomposite films.It is also shown that the surface free energy of the film decreases with addition of nanosilica onto to PMMA matrix,but the water contact angle of the film increases with addition of nanosilica particles.By using tetrahydrofuran(THF) etched method,a kind of hydrophobic PMMA/SiO2 nanocomposite film was obtained.This method may dramatically enhance the water contact angle of the film.