[XPS investigation on the modified nano-Al2O3 by surface grafting]

Steric hindrance layer can be established when the surfaces of nano-Al2O3 were grafted with polyacetal, which increased the dispersibility of the nano-particles as well as the compatibility between the particles and the resin matrix. Examination of X-ray photoelectron spectroscopy (XPS) demonstrated that the peak of Al(2p) on polyacetal grafted Al2O3 surfaces almost disappeared, while that of O(1s) increased. On the contrary, peak of C(1s) increased obviously. Results of fine scanning and deconvolution into multiple sub-peaks of C(1s) indicated that 61.92% of carbon on the surfaces of nano-Al2O3 was attributed to the grafting polyacetal. This shows that an effective modification layer formed on Al2O3 surfaces, and the grafting polyacetal was chemically bound with nano-Al2O3. Based on XPS and TG analysis, it is conjectured that the grafting polyacetal is mainly distributed on nano-Al2O3 surfaces.