Abstract: Surface structure and properties of the untreated, treated and grafted wood were analyzed by X-ray photo electron spectroscopy(XPS).XPS spectra showed that:1)Microwave plasma treatment increased the O/C atomic ratio of the wood surface, diminished C1(carbon bonded to carbon and/or hydrogen), increased C2(carbon bonded to a single oxygen) and C3(carbon bonded to two non carbonyl oxygen or to a carbonyl oxygen), and generated C4(carbon bonded to a carbonyl and a non carbonyl oxygen).These results suggest that a great deal of oxygenated groups or peroxides were generated on wood surface after microwave plasma(MWP) treatment; 2)The O/C ratio of the grafted wood by MWP initiation was higher than that of untreated wood, but lower than that of treated wood by MWP;the main changes of C1s spectral peak of grafted wood were the generation of C4 intense peak, suggesting the generation of a good deal of O-C=O groups on wood surface; 3)The O1/O2 ratio of the grafted wood is about 1, higher than that of the untreated wood and treated wood by MWP, showing the considerable increase of C=O content in grafted wood.These results showed that a great deal of methyl methacrylate(MMA) molecules were grafted onto wood surface.

Key words: microwave plasma, Alnus nepalensis D.Don, graft polymerization, methyl methacrylate, X-ray photoelectron spectroscopy