Abstract: Composite treating solutions from polyvinyl alcohol((PVA) and organic montmorillonite(MMT) were prepared through one-step and two-step method respectively and used to impregnate Chinese fir(Cunninghamia lanceolata)sapwood specimens by full-cell vacum-pressure process to produce MMT/PVA/wood composite(PVDMW).The water adsorption, antishrinking efficiency(A_S), surface hardness, compression strength parallel to grain and leaching resistance of composites prepared through two methods were determined. Fourier transform infrared spectroscopy(FT-IR)was used to analyze its mechanism of improving the properties of wood. The results showed that A_S and leaching resistance of PVDMW-1 prepared by one-step method were obviously higher than PVDMW-2 prepared by two-step method, while water absorption and compressive strength parallel to grain of both composites were similar, and the surface hardness of PVDMW-2 was higher than that of PVDMW-1. From FT-IR analysis, the characteristic peaks of MMT were observed in PVDMW-1. It suggested that MMT entered into the wood cell wall in the composite prepared by one-step method.

Key words: Chinese fir, montmorillonite, polyvinyl alcohol