纳米SiC表面接枝修饰的XPS研究

聚合物在纳米粒子表面接枝后,可在其表面建立起空间位阻稳定层,提高纳米粒子的分散稳定性及其与树脂基体的相容性.本文采用缩聚法在纳米SiC表面接枝了聚缩醛,X射线光电子能谱(XPS)的分析结果表明,经过聚缩醛接枝改性的纳米SiC表面Si2p峰明显降低,而C1s峰和O1s峰明显地增长,对C1s、Si2p峰精细扫描及分峰拟合表明,纳米SiC表面碳元素中有38.4%属于接枝物聚缩醛的有机碳,而79.8%的Si元素结合能增加了2.5eV,由此表明,纳米SiC表面形成了良好的表面修饰层,接枝物聚缩醛以化学键结合于纳米SiC表面;对比XPS和热失重分析(TG)的数据结果,可以推测,聚缩醛主要分布在纳米SiC的表面,而在体相中独立存在的几率较小.

XPS Study of Modified Nano-SiC by Surface Grafting

The polyacetal polymer,grafted onto the surface of nano-SiC film by polycondensation,were characterized with X-ray photoelectron spectroscopy (XPS).The results show that the polyacetal grafting significantly affects the XPS spectra of the surface modified SiC.For example,the Si2p peak markedly lowers,whereas its C1s and O1s peaks considerably rise up.XPS fine scanning and a devolution into multiple sub peaks of the C1s and Si2p peaks reveal that 38.4 percent of C on the modified SiC surface originate from organic carbon of the grafted polyacetal.The devolution of the Si2p shows that the binding energy of 79.8 percent of Si increases by 2.5 eV,indicating the formation of a fairly good modified layer and a firm chemical binding of polyactal to nano-SiC film.The XPS and thermogravimetry (TG) results suggest that the grafted polyacetals do not diffuse into the bulk of SiC films.