A special synthetic reaction has been developed, in which vapor of the reactant interacts with the high temperature plasma generated by laser ablating a graphite target. By selecting chained methylsilicone as reactant, a series of methylsilsesquioxanes products with various structural configurations have been obtained. Among them, two products, which were separated by subilmation in high vacuum and recrystalization, were characterized by X-ray crystal diffraction as (CH3SiO1.5)n(n=8,10). Both of them are found to have three-dimensional cage structure. In addition, other products with double ring structure were detected by GC-MS analysis. The results demonstrate the potential application of the synthetic reaction. In the reaction described in this article, resulting from the collision and energy- transfer of the laser plasma, chain structure of the reactant dissociated and recombined to give the cage and ring structure of the products.

Key words: GRAPHITE, PLASMA POLYMERIZATION, LASER, SPUTTERING, ORGANO SILICON COMPOUNDS, METHYL-SILICONE, POLYSILOXANE P, SILOXANE, STRUCTURAL REARRANGEMENT